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Netronix MSP430 - Battery Driver #1

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Artox opened this issue Jan 21, 2020 · 8 comments
Open

Netronix MSP430 - Battery Driver #1

Artox opened this issue Jan 21, 2020 · 8 comments

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@Artox
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Artox commented Jan 21, 2020

The Embedded Controller provides status information about the battery.
This issue collects information and code drops related to implementing a driver that can ultimately report charge level and charging status.

@Artox
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Artox commented Jan 21, 2020

I have implemented a prototype driver: Artox/linux@aa739e5

Working:

  • registers a power supply of type battery
  • reads the voltage level from msp430 at 0x41
  • translates the reported level to uV based on a linear equation (approximate)
  • adds static battery information through device-tree

Nice to Have:

  • evaluate battery warning emitted by msp430
  • charging indication - based on ACIN presence <-- probably modeled as a power supply of type AC
  • find msp430 exposes a control interface for charging

neuschaefer pushed a commit that referenced this issue Mar 14, 2020
Mika spotted

<4>[17436.705441] general protection fault: 0000 [#1] PREEMPT SMP PTI
<4>[17436.705447] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 5.5.0+ #1
<4>[17436.705449] Hardware name: System manufacturer System Product Name/Z170M-PLUS, BIOS 3805 05/16/2018
<4>[17436.705512] RIP: 0010:__execlists_submission_tasklet+0xc4d/0x16e0 [i915]
<4>[17436.705516] Code: c5 4c 8d 60 e0 75 17 e9 8c 07 00 00 49 8b 44 24 20 49 39 c5 4c 8d 60 e0 0f 84 7a 07 00 00 49 8b 5c 24 08 49 8b 87 80 00 00 00 <48> 39 83 d8 fe ff ff 75 d9 48 8b 83 88 fe ff ff a8 01 0f 84 b6 05
<4>[17436.705518] RSP: 0018:ffffc9000012ce80 EFLAGS: 00010083
<4>[17436.705521] RAX: ffff88822ae42000 RBX: 5a5a5a5a5a5a5a5a RCX: dead000000000122
<4>[17436.705523] RDX: ffff88822ae42588 RSI: ffff8881e32a7908 RDI: ffff8881c429fd48
<4>[17436.705525] RBP: ffffc9000012cf00 R08: ffff88822ae42588 R09: 00000000fffffffe
<4>[17436.705527] R10: ffff8881c429fb80 R11: 00000000a677cf08 R12: ffff8881c42a0aa8
<4>[17436.705529] R13: ffff8881c429fd38 R14: ffff88822ae42588 R15: ffff8881c429fb80
<4>[17436.705532] FS:  0000000000000000(0000) GS:ffff88822ed00000(0000) knlGS:0000000000000000
<4>[17436.705534] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
<4>[17436.705536] CR2: 00007f858c76d000 CR3: 0000000005610003 CR4: 00000000003606e0
<4>[17436.705538] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
<4>[17436.705540] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
<4>[17436.705542] Call Trace:
<4>[17436.705545]  <IRQ>
<4>[17436.705603]  execlists_submission_tasklet+0xc0/0x130 [i915]

which is us consuming a partially initialised new waiter in
defer_requests(). We can prevent this by initialising the i915_dependency
prior to making it visible, and since we are using a concurrent
list_add/iterator mark them up to the compiler.

Fixes: 8ee36e0 ("drm/i915/execlists: Minimalistic timeslicing")
Signed-off-by: Chris Wilson <[email protected]>
Cc: Mika Kuoppala <[email protected]>
Reviewed-by: Mika Kuoppala <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
(cherry picked from commit f14f27b)
Signed-off-by: Jani Nikula <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
… delivery

After a treclaim, we expect to be in non-transactional state. If we
don't clear the current thread's MSR[TS] before we get preempted, then
tm_recheckpoint_new_task() will recheckpoint and we get rescheduled in
suspended transaction state.

When handling a signal caught in transactional state,
handle_rt_signal64() calls get_tm_stackpointer() that treclaims the
transaction using tm_reclaim_current() but without clearing the
thread's MSR[TS]. This can cause the TM Bad Thing exception below if
later we pagefault and get preempted trying to access the user's
sigframe, using __put_user(). Afterwards, when we are rescheduled back
into do_page_fault() (but now in suspended state since the thread's
MSR[TS] was not cleared), upon executing 'rfid' after completion of
the page fault handling, the exception is raised because a transition
from suspended to non-transactional state is invalid.

  Unexpected TM Bad Thing exception at c00000000000de44 (msr 0x8000000302a03031) tm_scratch=800000010280b033
  Oops: Unrecoverable exception, sig: 6 [#1]
  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
  CPU: 25 PID: 15547 Comm: a.out Not tainted 5.4.0-rc2 torvalds#32
  NIP:  c00000000000de44 LR: c000000000034728 CTR: 0000000000000000
  REGS: c00000003fe7bd70 TRAP: 0700   Not tainted  (5.4.0-rc2)
  MSR:  8000000302a03031 <SF,VEC,VSX,FP,ME,IR,DR,LE,TM[SE]>  CR: 44000884  XER: 00000000
  CFAR: c00000000000dda4 IRQMASK: 0
  PACATMSCRATCH: 800000010280b033
  GPR00: c000000000034728 c000000f65a17c80 c000000001662800 00007fffacf3fd78
  GPR04: 0000000000001000 0000000000001000 0000000000000000 c000000f611f8af0
  GPR08: 0000000000000000 0000000078006001 0000000000000000 000c000000000000
  GPR12: c000000f611f84b0 c00000003ffcb200 0000000000000000 0000000000000000
  GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR20: 0000000000000000 0000000000000000 0000000000000000 c000000f611f8140
  GPR24: 0000000000000000 00007fffacf3fd68 c000000f65a17d90 c000000f611f7800
  GPR28: c000000f65a17e90 c000000f65a17e90 c000000001685e18 00007fffacf3f000
  NIP [c00000000000de44] fast_exception_return+0xf4/0x1b0
  LR [c000000000034728] handle_rt_signal64+0x78/0xc50
  Call Trace:
  [c000000f65a17c80] [c000000000034710] handle_rt_signal64+0x60/0xc50 (unreliable)
  [c000000f65a17d30] [c000000000023640] do_notify_resume+0x330/0x460
  [c000000f65a17e20] [c00000000000dcc4] ret_from_except_lite+0x70/0x74
  Instruction dump:
  7c4ff120 e8410170 7c5a03a6 38400000 f8410060 e8010070 e8410080 e8610088
  60000000 60000000 e8810090 e8210078 <4c000024> 48000000 e8610178 88ed0989
  ---[ end trace 93094aa44b442f87 ]---

The simplified sequence of events that triggers the above exception is:

  ...				# userspace in NON-TRANSACTIONAL state
  tbegin			# userspace in TRANSACTIONAL state
  signal delivery		# kernelspace in SUSPENDED state
  handle_rt_signal64()
    get_tm_stackpointer()
      treclaim			# kernelspace in NON-TRANSACTIONAL state
    __put_user()
      page fault happens. We will never get back here because of the TM Bad Thing exception.

  page fault handling kicks in and we voluntarily preempt ourselves
  do_page_fault()
    __schedule()
      __switch_to(other_task)

  our task is rescheduled and we recheckpoint because the thread's MSR[TS] was not cleared
  __switch_to(our_task)
    switch_to_tm()
      tm_recheckpoint_new_task()
        trechkpt			# kernelspace in SUSPENDED state

  The page fault handling resumes, but now we are in suspended transaction state
  do_page_fault()    completes
  rfid     <----- trying to get back where the page fault happened (we were non-transactional back then)
  TM Bad Thing			# illegal transition from suspended to non-transactional

This patch fixes that issue by clearing the current thread's MSR[TS]
just after treclaim in get_tm_stackpointer() so that we stay in
non-transactional state in case we are preempted. In order to make
treclaim and clearing the thread's MSR[TS] atomic from a preemption
perspective when CONFIG_PREEMPT is set, preempt_disable/enable() is
used. It's also necessary to save the previous value of the thread's
MSR before get_tm_stackpointer() is called so that it can be exposed
to the signal handler later in setup_tm_sigcontexts() to inform the
userspace MSR at the moment of the signal delivery.

Found with tm-signal-context-force-tm kernel selftest.

Fixes: 2b0a576 ("powerpc: Add new transactional memory state to the signal context")
Cc: [email protected] # v3.9
Signed-off-by: Gustavo Luiz Duarte <[email protected]>
Acked-by: Michael Neuling <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
When health reporters are not supported, recovery function is invoked
directly, not via devlink health reporters.

In this direct flow, the recover function input parameter was passed
incorrectly and is causing a kernel oops. This patch is fixing the input
parameter.

Following call trace is observed on rx error health reporting.

Internal error: Oops: 96000007 [#1] PREEMPT SMP
Process kworker/u16:4 (pid: 4584, stack limit = 0x00000000c9e45703)
Call trace:
mlx5e_rx_reporter_err_rq_cqe_recover+0x30/0x164 [mlx5_core]
mlx5e_health_report+0x60/0x6c [mlx5_core]
mlx5e_reporter_rq_cqe_err+0x6c/0x90 [mlx5_core]
mlx5e_rq_err_cqe_work+0x20/0x2c [mlx5_core]
process_one_work+0x168/0x3d0
worker_thread+0x58/0x3d0
kthread+0x108/0x134

Fixes: c50de4a ("net/mlx5e: Generalize tx reporter's functionality")
Signed-off-by: Aya Levin <[email protected]>
Signed-off-by: Parav Pandit <[email protected]>
Reviewed-by: Tariq Toukan <[email protected]>
Signed-off-by: Saeed Mahameed <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
Damien Le Moal reports a lockdep splat with the acpi_power_meter,
observed with Linux v5.5 and later.

======================================================
WARNING: possible circular locking dependency detected
5.6.0-rc2+ torvalds#629 Not tainted
------------------------------------------------------
python/1397 is trying to acquire lock:
ffff888619080070 (&resource->lock){+.+.}, at: show_power+0x3c/0xa0 [acpi_power_meter]

               but task is already holding lock:
ffff88881643f188 (kn->count#119){++++}, at: kernfs_seq_start+0x6a/0x160

               which lock already depends on the new lock.

               the existing dependency chain (in reverse order) is:

               -> #1 (kn->count#119){++++}:
       __kernfs_remove+0x626/0x7e0
       kernfs_remove_by_name_ns+0x41/0x80
       remove_attrs+0xcb/0x3c0 [acpi_power_meter]
       acpi_power_meter_notify+0x1f7/0x310 [acpi_power_meter]
       acpi_ev_notify_dispatch+0x198/0x1f3
       acpi_os_execute_deferred+0x4d/0x70
       process_one_work+0x7c8/0x1340
       worker_thread+0x94/0xc70
       kthread+0x2ed/0x3f0
       ret_from_fork+0x24/0x30

               -> #0 (&resource->lock){+.+.}:
       __lock_acquire+0x20be/0x49b0
       lock_acquire+0x127/0x340
       __mutex_lock+0x15b/0x1350
       show_power+0x3c/0xa0 [acpi_power_meter]
       dev_attr_show+0x3f/0x80
       sysfs_kf_seq_show+0x216/0x410
       seq_read+0x407/0xf90
       vfs_read+0x152/0x2c0
       ksys_read+0xf3/0x1d0
       do_syscall_64+0x95/0x1010
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

               other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(kn->count#119);
                               lock(&resource->lock);
                               lock(kn->count#119);
  lock(&resource->lock);

                *** DEADLOCK ***
4 locks held by python/1397:
 #0: ffff8890242d64e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x9b/0xb0
 #1: ffff889040be74e0 (&p->lock){+.+.}, at: seq_read+0x6b/0xf90
 #2: ffff8890448eb880 (&of->mutex){+.+.}, at: kernfs_seq_start+0x47/0x160
 #3: ffff88881643f188 (kn->count#119){++++}, at: kernfs_seq_start+0x6a/0x160

               stack backtrace:
CPU: 10 PID: 1397 Comm: python Not tainted 5.6.0-rc2+ torvalds#629
Hardware name: Supermicro Super Server/X11DPL-i, BIOS 3.1 05/21/2019
Call Trace:
 dump_stack+0x97/0xe0
 check_noncircular+0x32e/0x3e0
 ? print_circular_bug.isra.0+0x1e0/0x1e0
 ? unwind_next_frame+0xb9a/0x1890
 ? entry_SYSCALL_64_after_hwframe+0x49/0xbe
 ? graph_lock+0x79/0x170
 ? __lockdep_reset_lock+0x3c0/0x3c0
 ? mark_lock+0xbc/0x1150
 __lock_acquire+0x20be/0x49b0
 ? mark_held_locks+0xe0/0xe0
 ? stack_trace_save+0x91/0xc0
 lock_acquire+0x127/0x340
 ? show_power+0x3c/0xa0 [acpi_power_meter]
 ? device_remove_bin_file+0x10/0x10
 ? device_remove_bin_file+0x10/0x10
 __mutex_lock+0x15b/0x1350
 ? show_power+0x3c/0xa0 [acpi_power_meter]
 ? show_power+0x3c/0xa0 [acpi_power_meter]
 ? mutex_lock_io_nested+0x11f0/0x11f0
 ? lock_downgrade+0x6a0/0x6a0
 ? kernfs_seq_start+0x47/0x160
 ? lock_acquire+0x127/0x340
 ? kernfs_seq_start+0x6a/0x160
 ? device_remove_bin_file+0x10/0x10
 ? show_power+0x3c/0xa0 [acpi_power_meter]
 show_power+0x3c/0xa0 [acpi_power_meter]
 dev_attr_show+0x3f/0x80
 ? memset+0x20/0x40
 sysfs_kf_seq_show+0x216/0x410
 seq_read+0x407/0xf90
 ? security_file_permission+0x16f/0x2c0
 vfs_read+0x152/0x2c0

Problem is that reading an attribute takes the kernfs lock in the kernfs
code, then resource->lock in the driver. During an ACPI notification, the
opposite happens: The resource lock is taken first, followed by the kernfs
lock when sysfs attributes are removed and re-created. Presumably this is
now seen due to some locking related changes in kernfs after v5.4, but it
was likely always a problem.

Fix the problem by not blindly acquiring the lock in the notification
function. It is only needed to protect the various update functions.
However, those update functions are called anyway when sysfs attributes
are read. This means that we can just stop calling those functions from
the notifier, and the resource lock in the notifier function is no longer
needed.

That leaves two situations:

First, METER_NOTIFY_CONFIG removes and re-allocates capability strings.
While it did so under the resource lock, _displaying_ those strings was not
protected, creating a race condition. To solve this problem, selectively
protect both removal/creation and reporting of capability attributes with
the resource lock.

Second, removing and re-creating the attribute files is no longer protected
by the resource lock. That doesn't matter since access to each individual
attribute is protected by the kernfs lock. Userspace may get messed up if
attributes disappear and reappear under its nose, but that is not different
than today, and there is nothing we can do about it without major driver
restructuring.

Last but not least, when removing the driver, remove attribute functions
first, then release capability strings. This avoids yet another race
condition.

Reported-by: Damien Le Moal <[email protected]>
Cc: Damien Le Moal <[email protected]>
Cc: [email protected] # v5.5+
Tested-by: Damien Le Moal <[email protected]>
Signed-off-by: Guenter Roeck <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
…eyond eof

While logging the prealloc extents of an inode during a fast fsync we call
btrfs_truncate_inode_items(), through btrfs_log_prealloc_extents(), while
holding a read lock on a leaf of the inode's root (not the log root, the
fs/subvol root), and then that function locks the file range in the inode's
iotree. This can lead to a deadlock when:

* the fsync is ranged

* the file has prealloc extents beyond eof

* writeback for a range different from the fsync range starts
  during the fsync

* the size of the file is not sector size aligned

Because when finishing an ordered extent we lock first a file range and
then try to COW the fs/subvol tree to insert an extent item.

The following diagram shows how the deadlock can happen.

           CPU 1                                        CPU 2

  btrfs_sync_file()
    --> for range [0, 1MiB)

    --> inode has a size of
        1MiB and has 1 prealloc
        extent beyond the
        i_size, starting at offset
        4MiB

    flushes all delalloc for the
    range [0MiB, 1MiB) and waits
    for the respective ordered
    extents to complete

                                              --> before task at CPU 1 locks the
                                                  inode, a write into file range
                                                  [1MiB, 2MiB + 1KiB) is made

                                              --> i_size is updated to 2MiB + 1KiB

                                              --> writeback is started for that
                                                  range, [1MiB, 2MiB + 4KiB)
                                                  --> end offset rounded up to
                                                      be sector size aligned

    btrfs_log_dentry_safe()
      btrfs_log_inode_parent()
        btrfs_log_inode()

          btrfs_log_changed_extents()
            btrfs_log_prealloc_extents()
              --> does a search on the
                  inode's root
              --> holds a read lock on
                  leaf X

                                              btrfs_finish_ordered_io()
                                                --> locks range [1MiB, 2MiB + 4KiB)
                                                    --> end offset rounded up
                                                        to be sector size aligned

                                                --> tries to cow leaf X, through
                                                    insert_reserved_file_extent()
                                                    --> already locked by the
                                                        task at CPU 1

              btrfs_truncate_inode_items()

                --> gets an i_size of
                    2MiB + 1KiB, which is
                    not sector size
                    aligned

                --> tries to lock file
                    range [2MiB, (u64)-1)
                    --> the start range
                        is rounded down
                        from 2MiB + 1K
                        to 2MiB to be sector
                        size aligned

                    --> but the subrange
                        [2MiB, 2MiB + 4KiB) is
                        already locked by
                        task at CPU 2 which
                        is waiting to get a
                        write lock on leaf X
                        for which we are
                        holding a read lock

                                *** deadlock ***

This results in a stack trace like the following, triggered by test case
generic/561 from fstests:

  [ 2779.973608] INFO: task kworker/u8:6:247 blocked for more than 120 seconds.
  [ 2779.979536]       Not tainted 5.6.0-rc2-btrfs-next-53 #1
  [ 2779.984503] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [ 2779.990136] kworker/u8:6    D    0   247      2 0x80004000
  [ 2779.990457] Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
  [ 2779.990466] Call Trace:
  [ 2779.990491]  ? __schedule+0x384/0xa30
  [ 2779.990521]  schedule+0x33/0xe0
  [ 2779.990616]  btrfs_tree_read_lock+0x19e/0x2e0 [btrfs]
  [ 2779.990632]  ? remove_wait_queue+0x60/0x60
  [ 2779.990730]  btrfs_read_lock_root_node+0x2f/0x40 [btrfs]
  [ 2779.990782]  btrfs_search_slot+0x510/0x1000 [btrfs]
  [ 2779.990869]  btrfs_lookup_file_extent+0x4a/0x70 [btrfs]
  [ 2779.990944]  __btrfs_drop_extents+0x161/0x1060 [btrfs]
  [ 2779.990987]  ? mark_held_locks+0x6d/0xc0
  [ 2779.990994]  ? __slab_alloc.isra.49+0x99/0x100
  [ 2779.991060]  ? insert_reserved_file_extent.constprop.19+0x64/0x300 [btrfs]
  [ 2779.991145]  insert_reserved_file_extent.constprop.19+0x97/0x300 [btrfs]
  [ 2779.991222]  ? start_transaction+0xdd/0x5c0 [btrfs]
  [ 2779.991291]  btrfs_finish_ordered_io+0x4f4/0x840 [btrfs]
  [ 2779.991405]  btrfs_work_helper+0xaa/0x720 [btrfs]
  [ 2779.991432]  process_one_work+0x26d/0x6a0
  [ 2779.991460]  worker_thread+0x4f/0x3e0
  [ 2779.991481]  ? process_one_work+0x6a0/0x6a0
  [ 2779.991489]  kthread+0x103/0x140
  [ 2779.991499]  ? kthread_create_worker_on_cpu+0x70/0x70
  [ 2779.991515]  ret_from_fork+0x3a/0x50
  (...)
  [ 2780.026211] INFO: task fsstress:17375 blocked for more than 120 seconds.
  [ 2780.027480]       Not tainted 5.6.0-rc2-btrfs-next-53 #1
  [ 2780.028482] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [ 2780.030035] fsstress        D    0 17375  17373 0x00004000
  [ 2780.030038] Call Trace:
  [ 2780.030044]  ? __schedule+0x384/0xa30
  [ 2780.030052]  schedule+0x33/0xe0
  [ 2780.030075]  lock_extent_bits+0x20c/0x320 [btrfs]
  [ 2780.030094]  ? btrfs_truncate_inode_items+0xf4/0x1150 [btrfs]
  [ 2780.030098]  ? rcu_read_lock_sched_held+0x59/0xa0
  [ 2780.030102]  ? remove_wait_queue+0x60/0x60
  [ 2780.030122]  btrfs_truncate_inode_items+0x133/0x1150 [btrfs]
  [ 2780.030151]  ? btrfs_set_path_blocking+0xb2/0x160 [btrfs]
  [ 2780.030165]  ? btrfs_search_slot+0x379/0x1000 [btrfs]
  [ 2780.030195]  btrfs_log_changed_extents.isra.8+0x841/0x93e [btrfs]
  [ 2780.030202]  ? do_raw_spin_unlock+0x49/0xc0
  [ 2780.030215]  ? btrfs_get_num_csums+0x10/0x10 [btrfs]
  [ 2780.030239]  btrfs_log_inode+0xf83/0x1124 [btrfs]
  [ 2780.030251]  ? __mutex_unlock_slowpath+0x45/0x2a0
  [ 2780.030275]  btrfs_log_inode_parent+0x2a0/0xe40 [btrfs]
  [ 2780.030282]  ? dget_parent+0xa1/0x370
  [ 2780.030309]  btrfs_log_dentry_safe+0x4a/0x70 [btrfs]
  [ 2780.030329]  btrfs_sync_file+0x3f3/0x490 [btrfs]
  [ 2780.030339]  do_fsync+0x38/0x60
  [ 2780.030343]  __x64_sys_fdatasync+0x13/0x20
  [ 2780.030345]  do_syscall_64+0x5c/0x280
  [ 2780.030348]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [ 2780.030356] RIP: 0033:0x7f2d80f6d5f0
  [ 2780.030361] Code: Bad RIP value.
  [ 2780.030362] RSP: 002b:00007ffdba3c8548 EFLAGS: 00000246 ORIG_RAX: 000000000000004b
  [ 2780.030364] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f2d80f6d5f0
  [ 2780.030365] RDX: 00007ffdba3c84b0 RSI: 00007ffdba3c84b0 RDI: 0000000000000003
  [ 2780.030367] RBP: 000000000000004a R08: 0000000000000001 R09: 00007ffdba3c855c
  [ 2780.030368] R10: 0000000000000078 R11: 0000000000000246 R12: 00000000000001f4
  [ 2780.030369] R13: 0000000051eb851f R14: 00007ffdba3c85f0 R15: 0000557a49220d90

So fix this by making btrfs_truncate_inode_items() not lock the range in
the inode's iotree when the target root is a log root, since it's not
needed to lock the range for log roots as the protection from the inode's
lock and log_mutex are all that's needed.

Fixes: 28553fa ("Btrfs: fix race between shrinking truncate and fiemap")
CC: [email protected] # 4.4+
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: David Sterba <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
Loading the driver on a system with W83627DHG-P crashes as follows.

w83627ehf: Found W83627DHG-P chip at 0x290
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 0 P4D 0
Oops: 0000 [#1] SMP NOPTI
CPU: 0 PID: 604 Comm: sensors Not tainted 5.6.0-rc2-00055-gca7e1fd1026c torvalds#29
Hardware name:  /D425KT, BIOS MWPNT10N.86A.0132.2013.0726.1534 07/26/2013
RIP: 0010:w83627ehf_read_string+0x27/0x70 [w83627ehf]
Code: [... ]
RSP: 0018:ffffb95980657df8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff96caaa7f5218 RCX: 0000000000000000
RDX: 0000000000000015 RSI: 0000000000000001 RDI: ffff96caa736ec08
RBP: 0000000000000000 R08: ffffb95980657e20 R09: 0000000000000001
R10: ffff96caaa635cc0 R11: 0000000000000000 R12: ffff96caa9f7cf00
R13: ffff96caa9ec3d00 R14: ffff96caa9ec3d28 R15: ffff96caa9ec3d40
FS:  00007fbc7c4e2740(0000) GS:ffff96caabc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000129d58000 CR4: 00000000000006f0
Call Trace:
 ? cp_new_stat+0x12d/0x160
 hwmon_attr_show_string+0x37/0x70 [hwmon]
 dev_attr_show+0x14/0x50
 sysfs_kf_seq_show+0xb5/0x1b0
 seq_read+0xcf/0x460
 vfs_read+0x9b/0x150
 ksys_read+0x5f/0xe0
 do_syscall_64+0x48/0x190
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
...

Temperature labels are not always present. Adjust sysfs attribute
visibility accordingly.

Reported-by: Meelis Roos <[email protected]>
Suggested-by: Dr. David Alan Gilbert <[email protected]>
Reviewed-by: Dr. David Alan Gilbert <[email protected]>
Cc: Meelis Roos <[email protected]>
Cc: Dr. David Alan Gilbert <[email protected]>
Fixes: 266cd58 ("hwmon: (w83627ehf) convert to with_info interface")
Signed-off-by: Guenter Roeck <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
When we use SPARSEMEM instead of SPARSEMEM_VMEMMAP, pfn_to_page()
doesn't work before sparse_init_one_section() is called.

This leads to a crash when hotplug memory:

    BUG: unable to handle page fault for address: 0000000006400000
    #PF: supervisor write access in kernel mode
    #PF: error_code(0x0002) - not-present page
    PGD 0 P4D 0
    Oops: 0002 [#1] SMP PTI
    CPU: 3 PID: 221 Comm: kworker/u16:1 Tainted: G        W         5.5.0-next-20200205+ torvalds#343
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
    Workqueue: kacpi_hotplug acpi_hotplug_work_fn
    RIP: 0010:__memset+0x24/0x30
    Code: cc cc cc cc cc cc 0f 1f 44 00 00 49 89 f9 48 89 d1 83 e2 07 48 c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 <f3> 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3
    RSP: 0018:ffffb43ac0373c80 EFLAGS: 00010a87
    RAX: ffffffffffffffff RBX: ffff8a1518800000 RCX: 0000000000050000
    RDX: 0000000000000000 RSI: 00000000000000ff RDI: 0000000006400000
    RBP: 0000000000140000 R08: 0000000000100000 R09: 0000000006400000
    R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000
    R13: 0000000000000028 R14: 0000000000000000 R15: ffff8a153ffd9280
    FS:  0000000000000000(0000) GS:ffff8a153ab00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000006400000 CR3: 0000000136fca000 CR4: 00000000000006e0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
     sparse_add_section+0x1c9/0x26a
     __add_pages+0xbf/0x150
     add_pages+0x12/0x60
     add_memory_resource+0xc8/0x210
     __add_memory+0x62/0xb0
     acpi_memory_device_add+0x13f/0x300
     acpi_bus_attach+0xf6/0x200
     acpi_bus_scan+0x43/0x90
     acpi_device_hotplug+0x275/0x3d0
     acpi_hotplug_work_fn+0x1a/0x30
     process_one_work+0x1a7/0x370
     worker_thread+0x30/0x380
     kthread+0x112/0x130
     ret_from_fork+0x35/0x40

We should use memmap as it did.

On x86 the impact is limited to x86_32 builds, or x86_64 configurations
that override the default setting for SPARSEMEM_VMEMMAP.

Other memory hotplug archs (arm64, ia64, and ppc) also default to
SPARSEMEM_VMEMMAP=y.

[[email protected]: changelog update]
{[email protected]: changelog update]
Link: http://lkml.kernel.org/r/[email protected]
Fixes: ba72b4c ("mm/sparsemem: support sub-section hotplug")
Signed-off-by: Wei Yang <[email protected]>
Signed-off-by: Baoquan He <[email protected]>
Acked-by: David Hildenbrand <[email protected]>
Reviewed-by: Baoquan He <[email protected]>
Reviewed-by: Dan Williams <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
I found a NULL pointer dereference in ocfs2_block_group_clear_bits().
The running environment:
	kernel version: 4.19
	A cluster with two nodes, 5 luns mounted on two nodes, and do some
	file operations like dd/fallocate/truncate/rm on every lun with storage
	network disconnection.

The fallocate operation on dm-23-45 caused an null pointer dereference.

The information of NULL pointer dereference as follows:
	[577992.878282] JBD2: Error -5 detected when updating journal superblock for dm-23-45.
	[577992.878290] Aborting journal on device dm-23-45.
	...
	[577992.890778] JBD2: Error -5 detected when updating journal superblock for dm-24-46.
	[577992.890908] __journal_remove_journal_head: freeing b_committed_data
	[577992.890916] (fallocate,88392,52):ocfs2_extend_trans:474 ERROR: status = -30
	[577992.890918] __journal_remove_journal_head: freeing b_committed_data
	[577992.890920] (fallocate,88392,52):ocfs2_rotate_tree_right:2500 ERROR: status = -30
	[577992.890922] __journal_remove_journal_head: freeing b_committed_data
	[577992.890924] (fallocate,88392,52):ocfs2_do_insert_extent:4382 ERROR: status = -30
	[577992.890928] (fallocate,88392,52):ocfs2_insert_extent:4842 ERROR: status = -30
	[577992.890928] __journal_remove_journal_head: freeing b_committed_data
	[577992.890930] (fallocate,88392,52):ocfs2_add_clusters_in_btree:4947 ERROR: status = -30
	[577992.890933] __journal_remove_journal_head: freeing b_committed_data
	[577992.890939] __journal_remove_journal_head: freeing b_committed_data
	[577992.890949] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
	[577992.890950] Mem abort info:
	[577992.890951]   ESR = 0x96000004
	[577992.890952]   Exception class = DABT (current EL), IL = 32 bits
	[577992.890952]   SET = 0, FnV = 0
	[577992.890953]   EA = 0, S1PTW = 0
	[577992.890954] Data abort info:
	[577992.890955]   ISV = 0, ISS = 0x00000004
	[577992.890956]   CM = 0, WnR = 0
	[577992.890958] user pgtable: 4k pages, 48-bit VAs, pgdp = 00000000f8da07a9
	[577992.890960] [0000000000000020] pgd=0000000000000000
	[577992.890964] Internal error: Oops: 96000004 [#1] SMP
	[577992.890965] Process fallocate (pid: 88392, stack limit = 0x00000000013db2fd)
	[577992.890968] CPU: 52 PID: 88392 Comm: fallocate Kdump: loaded Tainted: G        W  OE     4.19.36 #1
	[577992.890969] Hardware name: Huawei TaiShan 2280 V2/BC82AMDD, BIOS 0.98 08/25/2019
	[577992.890971] pstate: 60400009 (nZCv daif +PAN -UAO)
	[577992.891054] pc : _ocfs2_free_suballoc_bits+0x63c/0x968 [ocfs2]
	[577992.891082] lr : _ocfs2_free_suballoc_bits+0x618/0x968 [ocfs2]
	[577992.891084] sp : ffff0000c8e2b810
	[577992.891085] x29: ffff0000c8e2b820 x28: 0000000000000000
	[577992.891087] x27: 00000000000006f3 x26: ffffa07957b02e70
	[577992.891089] x25: ffff807c59d50000 x24: 00000000000006f2
	[577992.891091] x23: 0000000000000001 x22: ffff807bd39abc30
	[577992.891093] x21: ffff0000811d9000 x20: ffffa07535d6a000
	[577992.891097] x19: ffff000001681638 x18: ffffffffffffffff
	[577992.891098] x17: 0000000000000000 x16: ffff000080a03df0
	[577992.891100] x15: ffff0000811d9708 x14: 203d207375746174
	[577992.891101] x13: 73203a524f525245 x12: 20373439343a6565
	[577992.891103] x11: 0000000000000038 x10: 0101010101010101
	[577992.891106] x9 : ffffa07c68a85d70 x8 : 7f7f7f7f7f7f7f7f
	[577992.891109] x7 : 0000000000000000 x6 : 0000000000000080
	[577992.891110] x5 : 0000000000000000 x4 : 0000000000000002
	[577992.891112] x3 : ffff000001713390 x2 : 2ff90f88b1c22f00
	[577992.891114] x1 : ffff807bd39abc30 x0 : 0000000000000000
	[577992.891116] Call trace:
	[577992.891139]  _ocfs2_free_suballoc_bits+0x63c/0x968 [ocfs2]
	[577992.891162]  _ocfs2_free_clusters+0x100/0x290 [ocfs2]
	[577992.891185]  ocfs2_free_clusters+0x50/0x68 [ocfs2]
	[577992.891206]  ocfs2_add_clusters_in_btree+0x198/0x5e0 [ocfs2]
	[577992.891227]  ocfs2_add_inode_data+0x94/0xc8 [ocfs2]
	[577992.891248]  ocfs2_extend_allocation+0x1bc/0x7a8 [ocfs2]
	[577992.891269]  ocfs2_allocate_extents+0x14c/0x338 [ocfs2]
	[577992.891290]  __ocfs2_change_file_space+0x3f8/0x610 [ocfs2]
	[577992.891309]  ocfs2_fallocate+0xe4/0x128 [ocfs2]
	[577992.891316]  vfs_fallocate+0x11c/0x250
	[577992.891317]  ksys_fallocate+0x54/0x88
	[577992.891319]  __arm64_sys_fallocate+0x28/0x38
	[577992.891323]  el0_svc_common+0x78/0x130
	[577992.891325]  el0_svc_handler+0x38/0x78
	[577992.891327]  el0_svc+0x8/0xc

My analysis process as follows:
ocfs2_fallocate
  __ocfs2_change_file_space
    ocfs2_allocate_extents
      ocfs2_extend_allocation
        ocfs2_add_inode_data
          ocfs2_add_clusters_in_btree
            ocfs2_insert_extent
              ocfs2_do_insert_extent
                ocfs2_rotate_tree_right
                  ocfs2_extend_rotate_transaction
                    ocfs2_extend_trans
                      jbd2_journal_restart
                        jbd2__journal_restart
                          /* handle->h_transaction is NULL,
                           * is_handle_aborted(handle) is true
                           */
                          handle->h_transaction = NULL;
                          start_this_handle
                            return -EROFS;
            ocfs2_free_clusters
              _ocfs2_free_clusters
                _ocfs2_free_suballoc_bits
                  ocfs2_block_group_clear_bits
                    ocfs2_journal_access_gd
                      __ocfs2_journal_access
                        jbd2_journal_get_undo_access
                          /* I think jbd2_write_access_granted() will
                           * return true, because do_get_write_access()
                           * will return -EROFS.
                           */
                          if (jbd2_write_access_granted(...)) return 0;
                          do_get_write_access
                            /* handle->h_transaction is NULL, it will
                             * return -EROFS here, so do_get_write_access()
                             * was not called.
                             */
                            if (is_handle_aborted(handle)) return -EROFS;
                    /* bh2jh(group_bh) is NULL, caused NULL
                       pointer dereference */
                    undo_bg = (struct ocfs2_group_desc *)
                                bh2jh(group_bh)->b_committed_data;

If handle->h_transaction == NULL, then jbd2_write_access_granted()
does not really guarantee that journal_head will stay around,
not even speaking of its b_committed_data. The bh2jh(group_bh)
can be removed after ocfs2_journal_access_gd() and before call
"bh2jh(group_bh)->b_committed_data". So, we should move
is_handle_aborted() check from do_get_write_access() into
jbd2_journal_get_undo_access() and jbd2_journal_get_write_access()
before the call to jbd2_write_access_granted().

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Yan Wang <[email protected]>
Signed-off-by: Theodore Ts'o <[email protected]>
Reviewed-by: Jun Piao <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Cc: [email protected]
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
ALL_ENGINES reset doesn't clobber display with the current gvt-g
supported platforms. Thus ALL_ENGINES reset shouldn't reset the
display engine registers emulated by gvt-g.

This fixes guest warning like

[ 14.622026] [drm] Initialized i915 1.6.0 20200114 for 0000:00:03.0 on minor 0
[ 14.967917] fbcon: i915drmfb (fb0) is primary device
[ 25.100188] [drm:drm_atomic_helper_wait_for_dependencies [drm_kms_helper]] E RROR [CRTC:51:pipe A] flip_done timed out
[ 25.100860] -----------[ cut here ]-----------
[ 25.100861] pll on state mismatch (expected 0, found 1)
[ 25.101024] WARNING: CPU: 1 PID: 30 at drivers/gpu/drm/i915/display/intel_dis play.c:14382 verify_single_dpll_state.isra.115+0x28f/0x320 [i915]
[ 25.101025] Modules linked in: intel_rapl_msr intel_rapl_common kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel i915 aesni_intel cr ypto_simd cryptd glue_helper cec rc_core video drm_kms_helper joydev drm input_l eds i2c_algo_bit serio_raw fb_sys_fops syscopyarea sysfillrect sysimgblt mac_hid qemu_fw_cfg sch_fq_codel parport_pc ppdev lp parport ip_tables x_tables autofs4 e1000 psmouse i2c_piix4 pata_acpi floppy
[ 25.101052] CPU: 1 PID: 30 Comm: kworker/u4:1 Not tainted 5.5.0+ #1
[ 25.101053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1 .12.1-0-ga5cab58 04/01/2014
[ 25.101055] Workqueue: events_unbound async_run_entry_fn
[ 25.101092] RIP: 0010:verify_single_dpll_state.isra.115+0x28f/0x320 [i915]
[ 25.101093] Code: e0 d9 ff e9 a3 fe ff ff 80 3d e9 c2 11 00 00 44 89 f6 48 c7 c7 c0 9d 88 c0 75 3b e8 eb df d9 ff e9 c7 fe ff ff e8 d1 e0 ae c4 <0f> 0b e9 7a fe ff ff 80 3d c0 c2 11 00 00 8d 71 41 89 c2 48 c7 c7
[ 25.101093] RSP: 0018:ffffb1de80107878 EFLAGS: 00010286
[ 25.101094] RAX: 0000000000000000 RBX: ffffb1de80107884 RCX: 0000000000000007
[ 25.101095] RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff94fdfdd19740
[ 25.101095] RBP: ffffb1de80107938 R08: 0000000d6bfdc7b4 R09: 000000000000002b
[ 25.101096] R10: ffff94fdf82dc000 R11: 0000000000000225 R12: 00000000000001f8
[ 25.101096] R13: ffff94fdb3ca6a90 R14: ffff94fdb3ca0000 R15: 0000000000000000
[ 25.101097] FS: 0000000000000000(0000) GS:ffff94fdfdd00000(0000) knlGS:00000 00000000000
[ 25.101098] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 25.101098] CR2: 00007fbc3e2be9c8 CR3: 000000003339a003 CR4: 0000000000360ee0
[ 25.101101] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 25.101101] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 25.101102] Call Trace:
[ 25.101139] intel_atomic_commit_tail+0xde4/0x1520 [i915]
[ 25.101141] ? flush_workqueue_prep_pwqs+0xfa/0x130
[ 25.101142] ? flush_workqueue+0x198/0x3c0
[ 25.101174] intel_atomic_commit+0x2ad/0x320 [i915]
[ 25.101209] drm_atomic_commit+0x4a/0x50 [drm]
[ 25.101220] drm_client_modeset_commit_atomic+0x1c4/0x200 [drm]
[ 25.101231] drm_client_modeset_commit_force+0x47/0x170 [drm]
[ 25.101250] drm_fb_helper_restore_fbdev_mode_unlocked+0x4e/0xa0 [drm_kms_hel per]
[ 25.101255] drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper]
[ 25.101287] intel_fbdev_set_par+0x1a/0x40 [i915]
[ 25.101289] ? con_is_visible+0x2e/0x60
[ 25.101290] fbcon_init+0x378/0x600
[ 25.101292] visual_init+0xd5/0x130
[ 25.101296] do_bind_con_driver+0x217/0x430
[ 25.101297] do_take_over_console+0x7d/0x1b0
[ 25.101298] do_fbcon_takeover+0x5c/0xb0
[ 25.101299] fbcon_fb_registered+0x199/0x1a0
[ 25.101301] register_framebuffer+0x22c/0x330
[ 25.101306] __drm_fb_helper_initial_config_and_unlock+0x31a/0x520 [drm_kms_h elper]
[ 25.101311] drm_fb_helper_initial_config+0x35/0x40 [drm_kms_helper]
[ 25.101341] intel_fbdev_initial_config+0x18/0x30 [i915]
[ 25.101342] async_run_entry_fn+0x3c/0x150
[ 25.101343] process_one_work+0x1fd/0x3f0
[ 25.101344] worker_thread+0x34/0x410
[ 25.101346] kthread+0x121/0x140
[ 25.101346] ? process_one_work+0x3f0/0x3f0
[ 25.101347] ? kthread_park+0x90/0x90
[ 25.101350] ret_from_fork+0x35/0x40
[ 25.101351] --[ end trace b5b47d44cd998ba1 ]--

Fixes: 6294b61 ("drm/i915/gvt: add missing display part reset for vGPU reset")
Signed-off-by: Tina Zhang <[email protected]>
Reviewed-by: Zhenyu Wang <[email protected]>
Signed-off-by: Zhenyu Wang <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
Failures caused by GFP_ATOMIC memory pressure have been observed, and
due to the missing error handling, results in kernel crash such as

[1876998.350133] kernel BUG at mm/slub.c:3952!
[1876998.350141] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[1876998.350147] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 5.3.0-scnxt #1
[1876998.350150] Hardware name: N/A N/A/COMe-bIP2, BIOS CCR2R920 03/01/2017
[1876998.350160] RIP: 0010:kfree+0x1ca/0x220
[1876998.350164] Code: 85 db 74 49 48 8b 95 68 01 00 00 48 31 c2 48 89 10 e9 d7 fe ff ff 49 8b 04 24 a9 00 00 01 00 75 0b 49 8b 44 24 08 a8 01 75 02 <0f> 0b 49 8b 04 24 31 f6 a9 00 00 01 00 74 06 41 0f b6 74 24
 5b
[1876998.350172] RSP: 0018:ffffc900000f0df0 EFLAGS: 00010246
[1876998.350177] RAX: ffffea00027f0708 RBX: ffff888008d78000 RCX: 0000000000391372
[1876998.350181] RDX: 0000000000000000 RSI: ffffe8ffffd01400 RDI: ffff888008d78000
[1876998.350185] RBP: ffff8881185a5d00 R08: ffffc90000087dd8 R09: 000000000000280a
[1876998.350189] R10: 0000000000000002 R11: 0000000000000000 R12: ffffea0000235e00
[1876998.350193] R13: ffff8881185438a0 R14: 0000000000000000 R15: ffff888118543870
[1876998.350198] FS:  0000000000000000(0000) GS:ffff88811f300000(0000) knlGS:0000000000000000
[1876998.350203] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
s#1 Part1
[1876998.350206] CR2: 00007f8dac7b09f0 CR3: 000000011e20a006 CR4: 00000000001606e0
[1876998.350210] Call Trace:
[1876998.350215]  <IRQ>
[1876998.350224]  ? __netif_receive_skb_core+0x70a/0x920
[1876998.350229]  kfree_skb+0x32/0xb0
[1876998.350234]  __netif_receive_skb_core+0x70a/0x920
[1876998.350240]  __netif_receive_skb_one_core+0x36/0x80
[1876998.350245]  process_backlog+0x8b/0x150
[1876998.350250]  net_rx_action+0xf7/0x340
[1876998.350255]  __do_softirq+0x10f/0x353
[1876998.350262]  irq_exit+0xb2/0xc0
[1876998.350265]  do_IRQ+0x77/0xd0
[1876998.350271]  common_interrupt+0xf/0xf
[1876998.350274]  </IRQ>

In order to handle such failures more graceful, this change splits the
receive loop into one for consuming the received buffers, and one for
allocating new buffers.

When GFP_ATOMIC allocations fail, the receive will continue with the
buffers that is still there, and with the expectation that the allocations
will succeed in a later call to receive.

Fixes: 9274498 ("net: add Xilinx ll_temac device driver")
Signed-off-by: Esben Haabendal <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
Phil reports that adding elements, flushing and re-adding them
right away:

  nft add table t '{ set s { type ipv4_addr . inet_service; flags interval; }; }'
  nft add element t s '{ 10.0.0.1 . 22-25, 10.0.0.1 . 10-20 }'
  nft flush set t s
  nft add element t s '{ 10.0.0.1 . 10-20, 10.0.0.1 . 22-25 }'

triggers, almost reliably, a crash like this one:

  [   71.319848] general protection fault, probably for non-canonical address 0x6f6b6e696c2e756e: 0000 [#1] PREEMPT SMP PTI
  [   71.321540] CPU: 3 PID: 1201 Comm: kworker/3:2 Not tainted 5.6.0-rc1-00377-g2bb07f4e1d861 torvalds#192
  [   71.322746] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190711_202441-buildvm-armv7-10.arm.fedoraproject.org-2.fc31 04/01/2014
  [   71.324430] Workqueue: events nf_tables_trans_destroy_work [nf_tables]
  [   71.325387] RIP: 0010:nft_set_elem_destroy+0xa5/0x110 [nf_tables]
  [   71.326164] Code: 89 d4 84 c0 74 0e 8b 77 44 0f b6 f8 48 01 df e8 41 ff ff ff 45 84 e4 74 36 44 0f b6 63 08 45 84 e4 74 2c 49 01 dc 49 8b 04 24 <48> 8b 40 38 48 85 c0 74 4f 48 89 e7 4c 8b
  [   71.328423] RSP: 0018:ffffc9000226fd90 EFLAGS: 00010282
  [   71.329225] RAX: 6f6b6e696c2e756e RBX: ffff88813ab79f60 RCX: ffff88813931b5a0
  [   71.330365] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff88813ab79f9a
  [   71.331473] RBP: ffff88813ab79f60 R08: 0000000000000008 R09: 0000000000000000
  [   71.332627] R10: 000000000000021c R11: 0000000000000000 R12: ffff88813ab79fc2
  [   71.333615] R13: ffff88813b3adf50 R14: dead000000000100 R15: ffff88813931b8a0
  [   71.334596] FS:  0000000000000000(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000
  [   71.335780] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [   71.336577] CR2: 000055ac683710f0 CR3: 000000013a222003 CR4: 0000000000360ee0
  [   71.337533] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [   71.338557] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [   71.339718] Call Trace:
  [   71.340093]  nft_pipapo_destroy+0x7a/0x170 [nf_tables_set]
  [   71.340973]  nft_set_destroy+0x20/0x50 [nf_tables]
  [   71.341879]  nf_tables_trans_destroy_work+0x246/0x260 [nf_tables]
  [   71.342916]  process_one_work+0x1d5/0x3c0
  [   71.343601]  worker_thread+0x4a/0x3c0
  [   71.344229]  kthread+0xfb/0x130
  [   71.344780]  ? process_one_work+0x3c0/0x3c0
  [   71.345477]  ? kthread_park+0x90/0x90
  [   71.346129]  ret_from_fork+0x35/0x40
  [   71.346748] Modules linked in: nf_tables_set nf_tables nfnetlink 8021q [last unloaded: nfnetlink]
  [   71.348153] ---[ end trace 2eaa8149ca759bcc ]---
  [   71.349066] RIP: 0010:nft_set_elem_destroy+0xa5/0x110 [nf_tables]
  [   71.350016] Code: 89 d4 84 c0 74 0e 8b 77 44 0f b6 f8 48 01 df e8 41 ff ff ff 45 84 e4 74 36 44 0f b6 63 08 45 84 e4 74 2c 49 01 dc 49 8b 04 24 <48> 8b 40 38 48 85 c0 74 4f 48 89 e7 4c 8b
  [   71.350017] RSP: 0018:ffffc9000226fd90 EFLAGS: 00010282
  [   71.350019] RAX: 6f6b6e696c2e756e RBX: ffff88813ab79f60 RCX: ffff88813931b5a0
  [   71.350019] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff88813ab79f9a
  [   71.350020] RBP: ffff88813ab79f60 R08: 0000000000000008 R09: 0000000000000000
  [   71.350021] R10: 000000000000021c R11: 0000000000000000 R12: ffff88813ab79fc2
  [   71.350022] R13: ffff88813b3adf50 R14: dead000000000100 R15: ffff88813931b8a0
  [   71.350025] FS:  0000000000000000(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000
  [   71.350026] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [   71.350027] CR2: 000055ac683710f0 CR3: 000000013a222003 CR4: 0000000000360ee0
  [   71.350028] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [   71.350028] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [   71.350030] Kernel panic - not syncing: Fatal exception
  [   71.350412] Kernel Offset: disabled
  [   71.365922] ---[ end Kernel panic - not syncing: Fatal exception ]---

which is caused by dangling elements that have been deactivated, but
never removed.

On a flush operation, nft_pipapo_walk() walks through all the elements
in the mapping table, which are then deactivated by nft_flush_set(),
one by one, and added to the commit list for removal. Element data is
then freed.

On transaction commit, nft_pipapo_remove() is called, and failed to
remove these elements, leading to the stale references in the mapping.
The first symptom of this, revealed by KASan, is a one-byte
use-after-free in subsequent calls to nft_pipapo_walk(), which is
usually not enough to trigger a panic. When stale elements are used
more heavily, though, such as double-free via nft_pipapo_destroy()
as in Phil's case, the problem becomes more noticeable.

The issue comes from that fact that, on a flush operation,
nft_pipapo_remove() won't get the actual key data via elem->key,
elements to be deleted upon commit won't be found by the lookup via
pipapo_get(), and removal will be skipped. Key data should be fetched
via nft_set_ext_key(), instead.

Reported-by: Phil Sutter <[email protected]>
Fixes: 3c4287f ("nf_tables: Add set type for arbitrary concatenation of ranges")
Signed-off-by: Stefano Brivio <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
IPV6_ADDRFORM is able to transform IPv6 socket to IPv4 one.
While this operation sounds illogical, we have to support it.

One of the things it does for TCP socket is to switch sk->sk_prot
to tcp_prot.

We now have other layers playing with sk->sk_prot, so we should make
sure to not interfere with them.

This patch makes sure sk_prot is the default pointer for TCP IPv6 socket.

syzbot reported :
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD a0113067 P4D a0113067 PUD a8771067 PMD 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 10686 Comm: syz-executor.0 Not tainted 5.6.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffffc9000281fce0 EFLAGS: 00010246
RAX: 1ffffffff15f48ac RBX: ffffffff8afa4560 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880a69a8f40
RBP: ffffc9000281fd10 R08: ffffffff86ed9b0c R09: ffffed1014d351f5
R10: ffffed1014d351f5 R11: 0000000000000000 R12: ffff8880920d3098
R13: 1ffff1101241a613 R14: ffff8880a69a8f40 R15: 0000000000000000
FS:  00007f2ae75db700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000000a3b85000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 inet_release+0x165/0x1c0 net/ipv4/af_inet.c:427
 __sock_release net/socket.c:605 [inline]
 sock_close+0xe1/0x260 net/socket.c:1283
 __fput+0x2e4/0x740 fs/file_table.c:280
 ____fput+0x15/0x20 fs/file_table.c:313
 task_work_run+0x176/0x1b0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop arch/x86/entry/common.c:164 [inline]
 prepare_exit_to_usermode+0x480/0x5b0 arch/x86/entry/common.c:195
 syscall_return_slowpath+0x113/0x4a0 arch/x86/entry/common.c:278
 do_syscall_64+0x11f/0x1c0 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c429
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f2ae75dac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: 0000000000000000 RBX: 00007f2ae75db6d4 RCX: 000000000045c429
RDX: 0000000000000001 RSI: 000000000000011a RDI: 0000000000000004
RBP: 000000000076bf20 R08: 0000000000000038 R09: 0000000000000000
R10: 0000000020000180 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000a9d R14: 00000000004ccfb4 R15: 000000000076bf2c
Modules linked in:
CR2: 0000000000000000
---[ end trace 82567b5207e87bae ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffffc9000281fce0 EFLAGS: 00010246
RAX: 1ffffffff15f48ac RBX: ffffffff8afa4560 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880a69a8f40
RBP: ffffc9000281fd10 R08: ffffffff86ed9b0c R09: ffffed1014d351f5
R10: ffffed1014d351f5 R11: 0000000000000000 R12: ffff8880920d3098
R13: 1ffff1101241a613 R14: ffff8880a69a8f40 R15: 0000000000000000
FS:  00007f2ae75db700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000000a3b85000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Fixes: 604326b ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Eric Dumazet <[email protected]>
Reported-by: [email protected]
Cc: Daniel Borkmann <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
syzbot noted that the master MPTCP socket lacks the icsk_sync_mss
callback, and was able to trigger a null pointer dereference:

BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 8e171067 P4D 8e171067 PUD 93fa2067 PMD 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 8984 Comm: syz-executor066 Not tainted 5.6.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffffc900020b7b80 EFLAGS: 00010246
RAX: 1ffff110124ba600 RBX: 0000000000000000 RCX: ffff88809fefa600
RDX: ffff8880994cdb18 RSI: 0000000000000000 RDI: ffff8880925d3140
RBP: ffffc900020b7bd8 R08: ffffffff870225be R09: fffffbfff140652a
R10: fffffbfff140652a R11: 0000000000000000 R12: ffff8880925d35d0
R13: ffff8880925d3140 R14: dffffc0000000000 R15: 1ffff110124ba6ba
FS:  0000000001a0b880(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000000a6d6f000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 cipso_v4_sock_setattr+0x34b/0x470 net/ipv4/cipso_ipv4.c:1888
 netlbl_sock_setattr+0x2a7/0x310 net/netlabel/netlabel_kapi.c:989
 smack_netlabel security/smack/smack_lsm.c:2425 [inline]
 smack_inode_setsecurity+0x3da/0x4a0 security/smack/smack_lsm.c:2716
 security_inode_setsecurity+0xb2/0x140 security/security.c:1364
 __vfs_setxattr_noperm+0x16f/0x3e0 fs/xattr.c:197
 vfs_setxattr fs/xattr.c:224 [inline]
 setxattr+0x335/0x430 fs/xattr.c:451
 __do_sys_fsetxattr fs/xattr.c:506 [inline]
 __se_sys_fsetxattr+0x130/0x1b0 fs/xattr.c:495
 __x64_sys_fsetxattr+0xbf/0xd0 fs/xattr.c:495
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440199
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffcadc19e48 EFLAGS: 00000246 ORIG_RAX: 00000000000000be
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440199
RDX: 0000000020000200 RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000003 R09: 00000000004002c8
R10: 0000000000000009 R11: 0000000000000246 R12: 0000000000401a20
R13: 0000000000401ab0 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
CR2: 0000000000000000

Address the issue adding a dummy icsk_sync_mss callback.
To properly sync the subflows mss and options list we need some
additional infrastructure, which will land to net-next.

Reported-by: [email protected]
Fixes: 2303f99 ("mptcp: Associate MPTCP context with TCP socket")
Signed-off-by: Paolo Abeni <[email protected]>
Reviewed-by: Mat Martineau <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
[ 3934.173244] ======================================================
[ 3934.179572] WARNING: possible circular locking dependency detected
[ 3934.185884] 5.4.21-xfstests #1 Not tainted
[ 3934.190151] ------------------------------------------------------
[ 3934.196673] dmsetup/8897 is trying to acquire lock:
[ 3934.201688] ffffffffbce82b18 (shrinker_rwsem){++++}, at: unregister_shrinker+0x22/0x80
[ 3934.210268]
               but task is already holding lock:
[ 3934.216489] ffff92a10cc5e1d0 (&pmd->root_lock){++++}, at: dm_pool_metadata_close+0xba/0x120
[ 3934.225083]
               which lock already depends on the new lock.

[ 3934.564165] Chain exists of:
                 shrinker_rwsem --> &journal->j_checkpoint_mutex --> &pmd->root_lock

For a more detailed lockdep report, please see:

	https://lore.kernel.org/r/[email protected]

We shouldn't need to hold the lock while are just tearing down and
freeing the whole metadata pool structure.

Fixes: 44d8ebf ("dm thin metadata: use pool locking at end of dm_pool_metadata_close")
Signed-off-by: Theodore Ts'o <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
Luo bin says:

====================
hinic: BugFixes

the bug fixed in patch #2 has been present since the first commit.
the bugs fixed in patch #1 and patch #3 have been present since the
following commits:
patch #1: 352f58b ("net-next/hinic: Set Rxq irq to specific cpu for NUMA")
patch #3: 421e952 ("hinic: add rss support")
====================

Signed-off-by: David S. Miller <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
rmnet_get_port() internally calls rcu_dereference_rtnl(),
which checks RTNL.
But rmnet_get_port() could be called by packet path.
The packet path is not protected by RTNL.
So, the suspicious RCU usage problem occurs.

Test commands:
    modprobe rmnet
    ip netns add nst
    ip link add veth0 type veth peer name veth1
    ip link set veth1 netns nst
    ip link add rmnet0 link veth0 type rmnet mux_id 1
    ip netns exec nst ip link add rmnet1 link veth1 type rmnet mux_id 1
    ip netns exec nst ip link set veth1 up
    ip netns exec nst ip link set rmnet1 up
    ip netns exec nst ip a a 192.168.100.2/24 dev rmnet1
    ip link set veth0 up
    ip link set rmnet0 up
    ip a a 192.168.100.1/24 dev rmnet0
    ping 192.168.100.2

Splat looks like:
[  146.630958][ T1174] WARNING: suspicious RCU usage
[  146.631735][ T1174] 5.6.0-rc1+ torvalds#447 Not tainted
[  146.632387][ T1174] -----------------------------
[  146.633151][ T1174] drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c:386 suspicious rcu_dereference_check() !
[  146.634742][ T1174]
[  146.634742][ T1174] other info that might help us debug this:
[  146.634742][ T1174]
[  146.645992][ T1174]
[  146.645992][ T1174] rcu_scheduler_active = 2, debug_locks = 1
[  146.646937][ T1174] 5 locks held by ping/1174:
[  146.647609][ T1174]  #0: ffff8880c31dea70 (sk_lock-AF_INET){+.+.}, at: raw_sendmsg+0xab8/0x2980
[  146.662463][ T1174]  #1: ffffffff93925660 (rcu_read_lock_bh){....}, at: ip_finish_output2+0x243/0x2150
[  146.671696][ T1174]  #2: ffffffff93925660 (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x213/0x2940
[  146.673064][ T1174]  #3: ffff8880c19ecd58 (&dev->qdisc_running_key#7){+...}, at: ip_finish_output2+0x714/0x2150
[  146.690358][ T1174]  #4: ffff8880c5796898 (&dev->qdisc_xmit_lock_key#3){+.-.}, at: sch_direct_xmit+0x1e2/0x1020
[  146.699875][ T1174]
[  146.699875][ T1174] stack backtrace:
[  146.701091][ T1174] CPU: 0 PID: 1174 Comm: ping Not tainted 5.6.0-rc1+ torvalds#447
[  146.705215][ T1174] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  146.706565][ T1174] Call Trace:
[  146.707102][ T1174]  dump_stack+0x96/0xdb
[  146.708007][ T1174]  rmnet_get_port.part.9+0x76/0x80 [rmnet]
[  146.709233][ T1174]  rmnet_egress_handler+0x107/0x420 [rmnet]
[  146.710492][ T1174]  ? sch_direct_xmit+0x1e2/0x1020
[  146.716193][ T1174]  rmnet_vnd_start_xmit+0x3d/0xa0 [rmnet]
[  146.717012][ T1174]  dev_hard_start_xmit+0x160/0x740
[  146.717854][ T1174]  sch_direct_xmit+0x265/0x1020
[  146.718577][ T1174]  ? register_lock_class+0x14d0/0x14d0
[  146.719429][ T1174]  ? dev_watchdog+0xac0/0xac0
[  146.723738][ T1174]  ? __dev_queue_xmit+0x15fd/0x2940
[  146.724469][ T1174]  ? lock_acquire+0x164/0x3b0
[  146.725172][ T1174]  __dev_queue_xmit+0x20c7/0x2940
[ ... ]

Fixes: ceed73a ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation")
Signed-off-by: Taehee Yoo <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
The notifier_call() of the slave interface removes rmnet interface with
unregister_netdevice_queue().
But, before calling unregister_netdevice_queue(), it acquires
rcu readlock.
In the RCU critical section, sleeping isn't be allowed.
But, unregister_netdevice_queue() internally calls synchronize_net(),
which would sleep.
So, suspicious RCU usage warning occurs.

Test commands:
    modprobe rmnet
    ip link add dummy0 type dummy
    ip link add dummy1 type dummy
    ip link add rmnet0 link dummy0 type rmnet mux_id 1
    ip link set dummy1 master rmnet0
    ip link del dummy0

Splat looks like:
[   79.639245][ T1195] =============================
[   79.640134][ T1195] WARNING: suspicious RCU usage
[   79.640852][ T1195] 5.6.0-rc1+ torvalds#447 Not tainted
[   79.641657][ T1195] -----------------------------
[   79.642472][ T1195] ./include/linux/rcupdate.h:273 Illegal context switch in RCU read-side critical section!
[   79.644043][ T1195]
[   79.644043][ T1195] other info that might help us debug this:
[   79.644043][ T1195]
[   79.645682][ T1195]
[   79.645682][ T1195] rcu_scheduler_active = 2, debug_locks = 1
[   79.646980][ T1195] 2 locks held by ip/1195:
[   79.647629][ T1195]  #0: ffffffffa3cf64f0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x457/0x890
[   79.649312][ T1195]  #1: ffffffffa39256c0 (rcu_read_lock){....}, at: rmnet_config_notify_cb+0xf0/0x590 [rmnet]
[   79.651717][ T1195]
[   79.651717][ T1195] stack backtrace:
[   79.652650][ T1195] CPU: 3 PID: 1195 Comm: ip Not tainted 5.6.0-rc1+ torvalds#447
[   79.653702][ T1195] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   79.655037][ T1195] Call Trace:
[   79.655560][ T1195]  dump_stack+0x96/0xdb
[   79.656252][ T1195]  ___might_sleep+0x345/0x440
[   79.656994][ T1195]  synchronize_net+0x18/0x30
[   79.661132][ T1195]  netdev_rx_handler_unregister+0x40/0xb0
[   79.666266][ T1195]  rmnet_unregister_real_device+0x42/0xb0 [rmnet]
[   79.667211][ T1195]  rmnet_config_notify_cb+0x1f7/0x590 [rmnet]
[   79.668121][ T1195]  ? rmnet_unregister_bridge.isra.6+0xf0/0xf0 [rmnet]
[   79.669166][ T1195]  ? rmnet_unregister_bridge.isra.6+0xf0/0xf0 [rmnet]
[   79.670286][ T1195]  ? __module_text_address+0x13/0x140
[   79.671139][ T1195]  notifier_call_chain+0x90/0x160
[   79.671973][ T1195]  rollback_registered_many+0x660/0xcf0
[   79.672893][ T1195]  ? netif_set_real_num_tx_queues+0x780/0x780
[   79.675091][ T1195]  ? __lock_acquire+0xdfe/0x3de0
[   79.675825][ T1195]  ? memset+0x1f/0x40
[   79.676367][ T1195]  ? __nla_validate_parse+0x98/0x1ab0
[   79.677290][ T1195]  unregister_netdevice_many.part.133+0x13/0x1b0
[   79.678163][ T1195]  rtnl_delete_link+0xbc/0x100
[ ... ]

Fixes: ceed73a ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation")
Signed-off-by: Taehee Yoo <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
netdev_upper_dev_link() is useful to manage lower/upper interfaces.
And this function internally validates looping, maximum depth.
All or most virtual interfaces that could have a real interface
(e.g. macsec, macvlan, ipvlan etc.) use lower/upper infrastructure.

Test commands:
    modprobe rmnet
    ip link add dummy0 type dummy
    ip link add rmnet1 link dummy0 type rmnet mux_id 1
    for i in {2..100}
    do
        let A=$i-1
        ip link add rmnet$i link rmnet$A type rmnet mux_id $i
    done
    ip link del dummy0

The purpose of the test commands is to make stack overflow.

Splat looks like:
[   52.411438][ T1395] BUG: KASAN: slab-out-of-bounds in find_busiest_group+0x27e/0x2c00
[   52.413218][ T1395] Write of size 64 at addr ffff8880c774bde0 by task ip/1395
[   52.414841][ T1395]
[   52.430720][ T1395] CPU: 1 PID: 1395 Comm: ip Not tainted 5.6.0-rc1+ torvalds#447
[   52.496511][ T1395] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   52.513597][ T1395] Call Trace:
[   52.546516][ T1395]
[   52.558773][ T1395] Allocated by task 3171537984:
[   52.588290][ T1395] BUG: unable to handle page fault for address: ffffffffb999e260
[   52.589311][ T1395] #PF: supervisor read access in kernel mode
[   52.590529][ T1395] #PF: error_code(0x0000) - not-present page
[   52.591374][ T1395] PGD d6818067 P4D d6818067 PUD d6819063 PMD 0
[   52.592288][ T1395] Thread overran stack, or stack corrupted
[   52.604980][ T1395] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[   52.605856][ T1395] CPU: 1 PID: 1395 Comm: ip Not tainted 5.6.0-rc1+ torvalds#447
[   52.611764][ T1395] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   52.621520][ T1395] RIP: 0010:stack_depot_fetch+0x10/0x30
[   52.622296][ T1395] Code: ff e9 f9 fe ff ff 48 89 df e8 9c 1d 91 ff e9 ca fe ff ff cc cc cc cc cc cc cc 89 f8 0
[   52.627887][ T1395] RSP: 0018:ffff8880c774bb60 EFLAGS: 00010006
[   52.628735][ T1395] RAX: 00000000001f8880 RBX: ffff8880c774d140 RCX: 0000000000000000
[   52.631773][ T1395] RDX: 000000000000001d RSI: ffff8880c774bb68 RDI: 0000000000003ff0
[   52.649584][ T1395] RBP: ffffea00031dd200 R08: ffffed101b43e403 R09: ffffed101b43e403
[   52.674857][ T1395] R10: 0000000000000001 R11: ffffed101b43e402 R12: ffff8880d900e5c0
[   52.678257][ T1395] R13: ffff8880c774c000 R14: 0000000000000000 R15: dffffc0000000000
[   52.694541][ T1395] FS:  00007fe867f6e0c0(0000) GS:ffff8880da000000(0000) knlGS:0000000000000000
[   52.764039][ T1395] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   52.815008][ T1395] CR2: ffffffffb999e260 CR3: 00000000c26aa005 CR4: 00000000000606e0
[   52.862312][ T1395] Call Trace:
[   52.887133][ T1395] Modules linked in: dummy rmnet veth openvswitch nsh nf_conncount nf_nat nf_conntrack nf_dex
[   52.936749][ T1395] CR2: ffffffffb999e260
[   52.965695][ T1395] ---[ end trace 7e32ca99482dbb31 ]---
[   52.966556][ T1395] RIP: 0010:stack_depot_fetch+0x10/0x30
[   52.971083][ T1395] Code: ff e9 f9 fe ff ff 48 89 df e8 9c 1d 91 ff e9 ca fe ff ff cc cc cc cc cc cc cc 89 f8 0
[   53.003650][ T1395] RSP: 0018:ffff8880c774bb60 EFLAGS: 00010006
[   53.043183][ T1395] RAX: 00000000001f8880 RBX: ffff8880c774d140 RCX: 0000000000000000
[   53.076480][ T1395] RDX: 000000000000001d RSI: ffff8880c774bb68 RDI: 0000000000003ff0
[   53.093858][ T1395] RBP: ffffea00031dd200 R08: ffffed101b43e403 R09: ffffed101b43e403
[   53.112795][ T1395] R10: 0000000000000001 R11: ffffed101b43e402 R12: ffff8880d900e5c0
[   53.139837][ T1395] R13: ffff8880c774c000 R14: 0000000000000000 R15: dffffc0000000000
[   53.141500][ T1395] FS:  00007fe867f6e0c0(0000) GS:ffff8880da000000(0000) knlGS:0000000000000000
[   53.143343][ T1395] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   53.152007][ T1395] CR2: ffffffffb999e260 CR3: 00000000c26aa005 CR4: 00000000000606e0
[   53.156459][ T1395] Kernel panic - not syncing: Fatal exception
[   54.213570][ T1395] Shutting down cpus with NMI
[   54.354112][ T1395] Kernel Offset: 0x33000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0x)
[   54.355687][ T1395] Rebooting in 5 seconds..

Fixes: b37f78f ("net: qualcomm: rmnet: Fix crash on real dev unregistration")
Signed-off-by: Taehee Yoo <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
…kernel/git/kvmarm/kvmarm into HEAD

KVM/arm fixes for 5.6, take #1

- Fix compilation on 32bit
- Move  VHE guest entry/exit into the VHE-specific entry code
- Make sure all functions called by the non-VHE HYP code is tagged as __always_inline
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
sel_lock cannot nest in the console lock. Thanks to syzkaller, the
kernel states firmly:

> WARNING: possible circular locking dependency detected
> 5.6.0-rc3-syzkaller #0 Not tainted
> ------------------------------------------------------
> syz-executor.4/20336 is trying to acquire lock:
> ffff8880a2e952a0 (&tty->termios_rwsem){++++}, at: tty_unthrottle+0x22/0x100 drivers/tty/tty_ioctl.c:136
>
> but task is already holding lock:
> ffffffff89462e70 (sel_lock){+.+.}, at: paste_selection+0x118/0x470 drivers/tty/vt/selection.c:374
>
> which lock already depends on the new lock.
>
> the existing dependency chain (in reverse order) is:
>
> -> #2 (sel_lock){+.+.}:
>        mutex_lock_nested+0x1b/0x30 kernel/locking/mutex.c:1118
>        set_selection_kernel+0x3b8/0x18a0 drivers/tty/vt/selection.c:217
>        set_selection_user+0x63/0x80 drivers/tty/vt/selection.c:181
>        tioclinux+0x103/0x530 drivers/tty/vt/vt.c:3050
>        vt_ioctl+0x3f1/0x3a30 drivers/tty/vt/vt_ioctl.c:364

This is ioctl(TIOCL_SETSEL).
Locks held on the path: console_lock -> sel_lock

> -> #1 (console_lock){+.+.}:
>        console_lock+0x46/0x70 kernel/printk/printk.c:2289
>        con_flush_chars+0x50/0x650 drivers/tty/vt/vt.c:3223
>        n_tty_write+0xeae/0x1200 drivers/tty/n_tty.c:2350
>        do_tty_write drivers/tty/tty_io.c:962 [inline]
>        tty_write+0x5a1/0x950 drivers/tty/tty_io.c:1046

This is write().
Locks held on the path: termios_rwsem -> console_lock

> -> #0 (&tty->termios_rwsem){++++}:
>        down_write+0x57/0x140 kernel/locking/rwsem.c:1534
>        tty_unthrottle+0x22/0x100 drivers/tty/tty_ioctl.c:136
>        mkiss_receive_buf+0x12aa/0x1340 drivers/net/hamradio/mkiss.c:902
>        tty_ldisc_receive_buf+0x12f/0x170 drivers/tty/tty_buffer.c:465
>        paste_selection+0x346/0x470 drivers/tty/vt/selection.c:389
>        tioclinux+0x121/0x530 drivers/tty/vt/vt.c:3055
>        vt_ioctl+0x3f1/0x3a30 drivers/tty/vt/vt_ioctl.c:364

This is ioctl(TIOCL_PASTESEL).
Locks held on the path: sel_lock -> termios_rwsem

> other info that might help us debug this:
>
> Chain exists of:
>   &tty->termios_rwsem --> console_lock --> sel_lock

Clearly. From the above, we have:
 console_lock -> sel_lock
 sel_lock -> termios_rwsem
 termios_rwsem -> console_lock

Fix this by reversing the console_lock -> sel_lock dependency in
ioctl(TIOCL_SETSEL). First, lock sel_lock, then console_lock.

Signed-off-by: Jiri Slaby <[email protected]>
Reported-by: [email protected]
Fixes: 07e6124 ("vt: selection, close sel_buffer race")
Cc: stable <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
journal_head::b_transaction and journal_head::b_next_transaction could
be accessed concurrently as noticed by KCSAN,

 LTP: starting fsync04
 /dev/zero: Can't open blockdev
 EXT4-fs (loop0): mounting ext3 file system using the ext4 subsystem
 EXT4-fs (loop0): mounted filesystem with ordered data mode. Opts: (null)
 ==================================================================
 BUG: KCSAN: data-race in __jbd2_journal_refile_buffer [jbd2] / jbd2_write_access_granted [jbd2]

 write to 0xffff99f9b1bd0e30 of 8 bytes by task 25721 on cpu 70:
  __jbd2_journal_refile_buffer+0xdd/0x210 [jbd2]
  __jbd2_journal_refile_buffer at fs/jbd2/transaction.c:2569
  jbd2_journal_commit_transaction+0x2d15/0x3f20 [jbd2]
  (inlined by) jbd2_journal_commit_transaction at fs/jbd2/commit.c:1034
  kjournald2+0x13b/0x450 [jbd2]
  kthread+0x1cd/0x1f0
  ret_from_fork+0x27/0x50

 read to 0xffff99f9b1bd0e30 of 8 bytes by task 25724 on cpu 68:
  jbd2_write_access_granted+0x1b2/0x250 [jbd2]
  jbd2_write_access_granted at fs/jbd2/transaction.c:1155
  jbd2_journal_get_write_access+0x2c/0x60 [jbd2]
  __ext4_journal_get_write_access+0x50/0x90 [ext4]
  ext4_mb_mark_diskspace_used+0x158/0x620 [ext4]
  ext4_mb_new_blocks+0x54f/0xca0 [ext4]
  ext4_ind_map_blocks+0xc79/0x1b40 [ext4]
  ext4_map_blocks+0x3b4/0x950 [ext4]
  _ext4_get_block+0xfc/0x270 [ext4]
  ext4_get_block+0x3b/0x50 [ext4]
  __block_write_begin_int+0x22e/0xae0
  __block_write_begin+0x39/0x50
  ext4_write_begin+0x388/0xb50 [ext4]
  generic_perform_write+0x15d/0x290
  ext4_buffered_write_iter+0x11f/0x210 [ext4]
  ext4_file_write_iter+0xce/0x9e0 [ext4]
  new_sync_write+0x29c/0x3b0
  __vfs_write+0x92/0xa0
  vfs_write+0x103/0x260
  ksys_write+0x9d/0x130
  __x64_sys_write+0x4c/0x60
  do_syscall_64+0x91/0xb05
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 5 locks held by fsync04/25724:
  #0: ffff99f9911093f8 (sb_writers#13){.+.+}, at: vfs_write+0x21c/0x260
  #1: ffff99f9db4c0348 (&sb->s_type->i_mutex_key#15){+.+.}, at: ext4_buffered_write_iter+0x65/0x210 [ext4]
  #2: ffff99f5e7dfcf58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2]
  #3: ffff99f9db4c0168 (&ei->i_data_sem){++++}, at: ext4_map_blocks+0x176/0x950 [ext4]
  #4: ffffffff99086b40 (rcu_read_lock){....}, at: jbd2_write_access_granted+0x4e/0x250 [jbd2]
 irq event stamp: 1407125
 hardirqs last  enabled at (1407125): [<ffffffff980da9b7>] __find_get_block+0x107/0x790
 hardirqs last disabled at (1407124): [<ffffffff980da8f9>] __find_get_block+0x49/0x790
 softirqs last  enabled at (1405528): [<ffffffff98a0034c>] __do_softirq+0x34c/0x57c
 softirqs last disabled at (1405521): [<ffffffff97cc67a2>] irq_exit+0xa2/0xc0

 Reported by Kernel Concurrency Sanitizer on:
 CPU: 68 PID: 25724 Comm: fsync04 Tainted: G L 5.6.0-rc2-next-20200221+ #7
 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019

The plain reads are outside of jh->b_state_lock critical section which result
in data races. Fix them by adding pairs of READ|WRITE_ONCE().

Reviewed-by: Jan Kara <[email protected]>
Signed-off-by: Qian Cai <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
Fixes the following NULL pointer dereference on PHY connect error path
teardown:

[    2.291010] sja1105 spi0.1: Probed switch chip: SJA1105T
[    2.310044] sja1105 spi0.1: Enabled switch tagging
[    2.314970] fsl-gianfar soc:ethernet@2d90000 eth2: error -19 setting up slave phy
[    2.322463] 8<--- cut here ---
[    2.325497] Unable to handle kernel NULL pointer dereference at virtual address 00000018
[    2.333555] pgd = (ptrval)
[    2.336241] [00000018] *pgd=00000000
[    2.339797] Internal error: Oops: 5 [#1] SMP ARM
[    2.344384] Modules linked in:
[    2.347420] CPU: 1 PID: 64 Comm: kworker/1:1 Not tainted 5.5.0-rc5 #1
[    2.353820] Hardware name: Freescale LS1021A
[    2.358070] Workqueue: events deferred_probe_work_func
[    2.363182] PC is at kthread_destroy_worker+0x4/0x74
[    2.368117] LR is at sja1105_teardown+0x70/0xb4
[    2.372617] pc : [<c036cdd4>]    lr : [<c0b89238>]    psr: 60000013
[    2.378845] sp : eeac3d30  ip : eeab1900  fp : eef45480
[    2.384036] r10: eef4549c  r9 : 00000001  r8 : 00000000
[    2.389227] r7 : eef527c0  r6 : 00000034  r5 : ed8ddd0c  r4 : ed8ddc40
[    2.395714] r3 : 00000000  r2 : 00000000  r1 : eef4549c  r0 : 00000000
[    2.402204] Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
[    2.409297] Control: 10c5387d  Table: 8020406a  DAC: 00000051
[    2.415008] Process kworker/1:1 (pid: 64, stack limit = 0x(ptrval))
[    2.421237] Stack: (0xeeac3d30 to 0xeeac4000)
[    2.612635] [<c036cdd4>] (kthread_destroy_worker) from [<c0b89238>] (sja1105_teardown+0x70/0xb4)
[    2.621379] [<c0b89238>] (sja1105_teardown) from [<c10717fc>] (dsa_switch_teardown.part.1+0x48/0x74)
[    2.630467] [<c10717fc>] (dsa_switch_teardown.part.1) from [<c1072438>] (dsa_register_switch+0x8b0/0xbf4)
[    2.639984] [<c1072438>] (dsa_register_switch) from [<c0b89c30>] (sja1105_probe+0x2ac/0x464)
[    2.648378] [<c0b89c30>] (sja1105_probe) from [<c0b11a5c>] (spi_drv_probe+0x7c/0xa0)
[    2.656081] [<c0b11a5c>] (spi_drv_probe) from [<c0a26ab8>] (really_probe+0x208/0x480)
[    2.663871] [<c0a26ab8>] (really_probe) from [<c0a26f0c>] (driver_probe_device+0x78/0x1c4)
[    2.672093] [<c0a26f0c>] (driver_probe_device) from [<c0a24c48>] (bus_for_each_drv+0x80/0xc4)
[    2.680574] [<c0a24c48>] (bus_for_each_drv) from [<c0a26810>] (__device_attach+0xd0/0x168)
[    2.688794] [<c0a26810>] (__device_attach) from [<c0a259d8>] (bus_probe_device+0x84/0x8c)
[    2.696927] [<c0a259d8>] (bus_probe_device) from [<c0a25f24>] (deferred_probe_work_func+0x84/0xc4)
[    2.705842] [<c0a25f24>] (deferred_probe_work_func) from [<c03667b0>] (process_one_work+0x22c/0x560)
[    2.714926] [<c03667b0>] (process_one_work) from [<c0366d8c>] (worker_thread+0x2a8/0x5d4)
[    2.723059] [<c0366d8c>] (worker_thread) from [<c036cf94>] (kthread+0x150/0x154)
[    2.730416] [<c036cf94>] (kthread) from [<c03010e8>] (ret_from_fork+0x14/0x2c)

Checking for NULL pointer is correct because the per-port xmit kernel
threads are created in sja1105_probe immediately after calling
dsa_register_switch.

Fixes: a68578c ("net: dsa: Make deferred_xmit private to sja1105")
Signed-off-by: Vladimir Oltean <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
Writing to the built-in strings arrays doesn't work if driver is loaded
as kernel module. This is also considered as a bad pattern. Fix this by
adding a call to clk_get() with legacy clock name. This fixes following
kernel oops if driver is loaded as module:

Unable to handle kernel paging request at virtual address bf047978
 pgd = (ptrval)
 [bf047978] *pgd=59344811, *pte=5903c6df, *ppte=5903c65f
 Internal error: Oops: 80f [#1] SMP ARM
 Modules linked in: mc exynosdrm(+) analogix_dp rtc_s3c exynos_ppmu i2c_gpio
 CPU: 1 PID: 212 Comm: systemd-udevd Not tainted 5.6.0-rc2-next-20200219 torvalds#326
 videodev: Linux video capture interface: v2.00
 Hardware name: Samsung Exynos (Flattened Device Tree)
 PC is at exynos_dsi_probe+0x1f0/0x384 [exynosdrm]
 LR is at exynos_dsi_probe+0x1dc/0x384 [exynosdrm]
 ...
 Process systemd-udevd (pid: 212, stack limit = 0x(ptrval))
 ...
 [<bf03cf14>] (exynos_dsi_probe [exynosdrm]) from [<c09b1ca0>] (platform_drv_probe+0x6c/0xa4)
 [<c09b1ca0>] (platform_drv_probe) from [<c09afcb8>] (really_probe+0x210/0x350)
 [<c09afcb8>] (really_probe) from [<c09aff74>] (driver_probe_device+0x60/0x1a0)
 [<c09aff74>] (driver_probe_device) from [<c09b0254>] (device_driver_attach+0x58/0x60)
 [<c09b0254>] (device_driver_attach) from [<c09b02dc>] (__driver_attach+0x80/0xbc)
 [<c09b02dc>] (__driver_attach) from [<c09ade00>] (bus_for_each_dev+0x68/0xb4)
 [<c09ade00>] (bus_for_each_dev) from [<c09aefd8>] (bus_add_driver+0x130/0x1e8)
 [<c09aefd8>] (bus_add_driver) from [<c09b0d64>] (driver_register+0x78/0x110)
 [<c09b0d64>] (driver_register) from [<bf038558>] (exynos_drm_init+0xe8/0x11c [exynosdrm])
 [<bf038558>] (exynos_drm_init [exynosdrm]) from [<c0302fa8>] (do_one_initcall+0x50/0x220)
 [<c0302fa8>] (do_one_initcall) from [<c03dd02c>] (do_init_module+0x60/0x210)
 [<c03dd02c>] (do_init_module) from [<c03dbf44>] (load_module+0x1c0c/0x2310)
 [<c03dbf44>] (load_module) from [<c03dc85c>] (sys_finit_module+0xac/0xbc)
 [<c03dc85c>] (sys_finit_module) from [<c0301000>] (ret_fast_syscall+0x0/0x54)
 Exception stack(0xd979bfa8 to 0xd979bff0)
 ...
 ---[ end trace db16efe05faab470 ]---

Signed-off-by: Marek Szyprowski <[email protected]>
Reviewed-by: Andrzej Hajda <[email protected]>
Signed-off-by: Inki Dae <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
719655a ("net: phy: Replace phy driver features u32 with link_mode
bitmap") was a bit over-eager and also removed the second phy driver's
name, resulting in a nasty OOPS on registration:

[    1.319854] CPU 0 Unable to handle kernel paging request at virtual address 00000000, epc == 804dd50c, ra == 804dd4f0
[    1.330859] Oops[#1]:
[    1.333138] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.4.22 #0
[    1.339217] $ 0   : 00000000 00000001 87ca7f00 805c1874
[    1.344590] $ 4   : 00000000 00000047 00585000 8701f800
[    1.349965] $ 8   : 8701f800 804f4a5c 00000003 64726976
[    1.355341] $12   : 00000001 00000000 00000000 00000114
[    1.360718] $16   : 87ca7f80 00000000 00000000 80639fe4
[    1.366093] $20   : 00000002 00000000 806441d0 80b90000
[    1.371470] $24   : 00000000 00000000
[    1.376847] $28   : 87c1e000 87c1fda0 80b90000 804dd4f0
[    1.382224] Hi    : d1c8f8da
[    1.385180] Lo    : 5518a480
[    1.388182] epc   : 804dd50c kset_find_obj+0x3c/0x114
[    1.393345] ra    : 804dd4f0 kset_find_obj+0x20/0x114
[    1.398530] Status: 10008703 KERNEL EXL IE
[    1.402833] Cause : 00800008 (ExcCode 02)
[    1.406952] BadVA : 00000000
[    1.409913] PrId  : 0002a075 (Broadcom BMIPS4350)
[    1.414745] Modules linked in:
[    1.417895] Process swapper/0 (pid: 1, threadinfo=(ptrval), task=(ptrval), tls=00000000)
[    1.426214] Stack : 87cec000 80630000 80639370 80640658 80640000 80049af4 80639fe4 8063a0d8
[    1.434816]         8063a0d8 802ef078 00000002 00000000 806441d0 80b90000 8063a0d8 802ef114
[    1.443417]         87cea0de 87c1fde0 00000000 804de488 87cea000 8063a0d8 8063a0d8 80334e48
[    1.452018]         80640000 8063984c 80639bf4 00000000 8065de48 00000001 8063a0d8 80334ed0
[    1.460620]         806441d0 80b90000 80b90000 802ef164 8065dd70 80620000 80b90000 8065de58
[    1.469222]         ...
[    1.471734] Call Trace:
[    1.474255] [<804dd50c>] kset_find_obj+0x3c/0x114
[    1.479141] [<802ef078>] driver_find+0x1c/0x44
[    1.483665] [<802ef114>] driver_register+0x74/0x148
[    1.488719] [<80334e48>] phy_driver_register+0x9c/0xd0
[    1.493968] [<80334ed0>] phy_drivers_register+0x54/0xe8
[    1.499345] [<8001061c>] do_one_initcall+0x7c/0x1f4
[    1.504374] [<80644ed8>] kernel_init_freeable+0x1d4/0x2b4
[    1.509940] [<804f4e24>] kernel_init+0x10/0xf8
[    1.514502] [<80018e68>] ret_from_kernel_thread+0x14/0x1c
[    1.520040] Code: 1060000c  02202025  90650000 <90810000> 24630001  14250004  24840001  14a0fffb  90650000
[    1.530061]
[    1.531698] ---[ end trace d52f1717cd29bdc8 ]---

Fix it by readding the name.

Fixes: 719655a ("net: phy: Replace phy driver features u32 with link_mode bitmap")
Signed-off-by: Jonas Gorski <[email protected]>
Acked-by: Florian Fainelli <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
Fix NULL pointer dereference in the error flow of ib_create_qp_user
when accessing to uninitialized list pointers - rdma_mrs and sig_mrs.
The following crash from syzkaller revealed it.

  kasan: GPF could be caused by NULL-ptr deref or user memory access
  general protection fault: 0000 [#1] SMP KASAN PTI
  CPU: 1 PID: 23167 Comm: syz-executor.1 Not tainted 5.5.0-rc5 #2
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
  rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
  RIP: 0010:ib_mr_pool_destroy+0x81/0x1f0
  Code: 00 00 fc ff df 49 c1 ec 03 4d 01 fc e8 a8 ea 72 fe 41 80 3c 24 00
  0f 85 62 01 00 00 48 8b 13 48 89 d6 4c 8d 6a c8 48 c1 ee 03 <42> 80 3c
  3e 00 0f 85 34 01 00 00 48 8d 7a 08 4c 8b 02 48 89 fe 48
  RSP: 0018:ffffc9000951f8b0 EFLAGS: 00010046
  RAX: 0000000000040000 RBX: ffff88810f268038 RCX: ffffffff82c41628
  RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc9000951f850
  RBP: ffff88810f268020 R08: 0000000000000004 R09: fffff520012a3f0a
  R10: 0000000000000001 R11: fffff520012a3f0a R12: ffffed1021e4d007
  R13: ffffffffffffffc8 R14: 0000000000000246 R15: dffffc0000000000
  FS:  00007f54bc788700(0000) GS:ffff88811b100000(0000)
  knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 0000000116920002 CR4: 0000000000360ee0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   rdma_rw_cleanup_mrs+0x15/0x30
   ib_destroy_qp_user+0x674/0x7d0
   ib_create_qp_user+0xb01/0x11c0
   create_qp+0x1517/0x2130
   ib_uverbs_create_qp+0x13e/0x190
   ib_uverbs_write+0xaa5/0xdf0
   __vfs_write+0x7c/0x100
   vfs_write+0x168/0x4a0
   ksys_write+0xc8/0x200
   do_syscall_64+0x9c/0x390
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
  RIP: 0033:0x465b49
  Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89
  f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01
  f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
  RSP: 002b:00007f54bc787c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
  RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000465b49
  RDX: 0000000000000040 RSI: 0000000020000540 RDI: 0000000000000003
  RBP: 00007f54bc787c70 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 00007f54bc7886bc
  R13: 00000000004ca2ec R14: 000000000070ded0 R15: 0000000000000005

Fixes: a060b56 ("IB/core: generic RDMA READ/WRITE API")
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Maor Gottlieb <[email protected]>
Signed-off-by: Leon Romanovsky <[email protected]>
Reviewed-by: Jason Gunthorpe <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
This fixes the kernel crash when a RDMA_NLDEV_CMD_STAT_SET command is
received, but the QP number parameter is not available.

  iwpm_register_pid: Unable to send a nlmsg (client = 2)
  infiniband syz1: RDMA CMA: cma_listen_on_dev, error -98
  general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
  KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
  CPU: 0 PID: 9754 Comm: syz-executor069 Not tainted 5.6.0-rc2-syzkaller #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
  RIP: 0010:nla_get_u32 include/net/netlink.h:1474 [inline]
  RIP: 0010:nldev_stat_set_doit+0x63c/0xb70 drivers/infiniband/core/nldev.c:1760
  Code: fc 01 0f 84 58 03 00 00 e8 41 83 bf fb 4c 8b a3 58 fd ff ff 48 b8 00 00 00 00 00 fc ff df 49 8d 7c 24 04 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 6d
  RSP: 0018:ffffc900068bf350 EFLAGS: 00010247
  RAX: dffffc0000000000 RBX: ffffc900068bf728 RCX: ffffffff85b60470
  RDX: 0000000000000000 RSI: ffffffff85b6047f RDI: 0000000000000004
  RBP: ffffc900068bf750 R08: ffff88808c3ee140 R09: ffff8880a25e6010
  R10: ffffed10144bcddc R11: ffff8880a25e6ee3 R12: 0000000000000000
  R13: ffff88809acb0000 R14: ffff888092a42c80 R15: 000000009ef2e29a
  FS:  0000000001ff0880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f4733e34000 CR3: 00000000a9b27000 CR4: 00000000001406f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
    rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:195 [inline]
    rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
    rdma_nl_rcv+0x5d9/0x980 drivers/infiniband/core/netlink.c:259
    netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
    netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1329
    netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1918
    sock_sendmsg_nosec net/socket.c:652 [inline]
    sock_sendmsg+0xd7/0x130 net/socket.c:672
    ____sys_sendmsg+0x753/0x880 net/socket.c:2343
    ___sys_sendmsg+0x100/0x170 net/socket.c:2397
    __sys_sendmsg+0x105/0x1d0 net/socket.c:2430
    __do_sys_sendmsg net/socket.c:2439 [inline]
    __se_sys_sendmsg net/socket.c:2437 [inline]
    __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437
    do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
    entry_SYSCALL_64_after_hwframe+0x49/0xbe
  RIP: 0033:0x4403d9
  Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
  RSP: 002b:00007ffc0efbc5c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
  RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004403d9
  RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000004
  RBP: 00000000006ca018 R08: 0000000000000008 R09: 00000000004002c8
  R10: 000000000000004a R11: 0000000000000246 R12: 0000000000401c60
  R13: 0000000000401cf0 R14: 0000000000000000 R15: 0000000000000000

Fixes: b389327 ("RDMA/nldev: Allow counter manual mode configration through RDMA netlink")
Link: https://lore.kernel.org/r/[email protected]
Reported-by: [email protected]
Signed-off-by: Mark Zhang <[email protected]>
Signed-off-by: Leon Romanovsky <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
Stefan reported a strange kernel fault which turned out to be due to a
missing KUAP disable in flush_coherent_icache() called from
flush_icache_range().

The fault looks like:

  Kernel attempted to access user page (7fffc30d9c00) - exploit attempt? (uid: 1009)
  BUG: Unable to handle kernel data access on read at 0x7fffc30d9c00
  Faulting instruction address: 0xc00000000007232c
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV
  CPU: 35 PID: 5886 Comm: sigtramp Not tainted 5.6.0-rc2-gcc-8.2.0-00003-gfc37a1632d40 torvalds#79
  NIP:  c00000000007232c LR: c00000000003b7fc CTR: 0000000000000000
  REGS: c000001e11093940 TRAP: 0300   Not tainted  (5.6.0-rc2-gcc-8.2.0-00003-gfc37a1632d40)
  MSR:  900000000280b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  CR: 28000884  XER: 00000000
  CFAR: c0000000000722fc DAR: 00007fffc30d9c00 DSISR: 08000000 IRQMASK: 0
  GPR00: c00000000003b7fc c000001e11093bd0 c0000000023ac200 00007fffc30d9c00
  GPR04: 00007fffc30d9c18 0000000000000000 c000001e11093bd4 0000000000000000
  GPR08: 0000000000000000 0000000000000001 0000000000000000 c000001e1104ed80
  GPR12: 0000000000000000 c000001fff6ab380 c0000000016be2d0 4000000000000000
  GPR16: c000000000000000 bfffffffffffffff 0000000000000000 0000000000000000
  GPR20: 00007fffc30d9c00 00007fffc30d8f58 00007fffc30d9c18 00007fffc30d9c20
  GPR24: 00007fffc30d9c18 0000000000000000 c000001e11093d90 c000001e1104ed80
  GPR28: c000001e11093e90 0000000000000000 c0000000023d9d18 00007fffc30d9c00
  NIP flush_icache_range+0x5c/0x80
  LR  handle_rt_signal64+0x95c/0xc2c
  Call Trace:
    0xc000001e11093d90 (unreliable)
    handle_rt_signal64+0x93c/0xc2c
    do_notify_resume+0x310/0x430
    ret_from_except_lite+0x70/0x74
  Instruction dump:
  409e002c 7c0802a6 3c62ff31 3863f6a0 f8010080 48195fed 60000000 48fe4c8d
  60000000 e8010080 7c0803a6 7c0004ac <7c00ffac> 7c0004ac 4c00012c 38210070

This path through handle_rt_signal64() to setup_trampoline() and
flush_icache_range() is only triggered by 64-bit processes that have
unmapped their VDSO, which is rare.

flush_icache_range() takes a range of addresses to flush. In
flush_coherent_icache() we implement an optimisation for CPUs where we
know we don't actually have to flush the whole range, we just need to
do a single icbi.

However we still execute the icbi on the user address of the start of
the range we're flushing. On CPUs that also implement KUAP (Power9)
that leads to the spurious fault above.

We should be able to pass any address, including a kernel address, to
the icbi on these CPUs, which would avoid any interaction with KUAP.
But I don't want to make that change in a bug fix, just in case it
surfaces some strange behaviour on some CPU.

So for now just disable KUAP around the icbi. Note the icbi is treated
as a load, so we allow read access, not write as you'd expect.

Fixes: 890274c ("powerpc/64s: Implement KUAP for Radix MMU")
Cc: [email protected] # v5.2+
Reported-by: Stefan Berger <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
The req->body should be updated before req->state is updated and the
order should be guaranteed by a barrier.

Otherwise, read_reply() might return req->body = NULL.

Below is sample callstack when the issue is reproduced on purpose by
reordering the updates of req->body and req->state and adding delay in
code between updates of req->state and req->body.

[   22.356105] general protection fault: 0000 [#1] SMP PTI
[   22.361185] CPU: 2 PID: 52 Comm: xenwatch Not tainted 5.5.0xen+ #6
[   22.366727] Hardware name: Xen HVM domU, BIOS ...
[   22.372245] RIP: 0010:_parse_integer_fixup_radix+0x6/0x60
... ...
[   22.392163] RSP: 0018:ffffb2d64023fdf0 EFLAGS: 00010246
[   22.395933] RAX: 0000000000000000 RBX: 75746e7562755f6d RCX: 0000000000000000
[   22.400871] RDX: 0000000000000000 RSI: ffffb2d64023fdfc RDI: 75746e7562755f6d
[   22.405874] RBP: 0000000000000000 R08: 00000000000001e8 R09: 0000000000cdcdcd
[   22.410945] R10: ffffb2d6402ffe00 R11: ffff9d95395eaeb0 R12: ffff9d9535935000
[   22.417613] R13: ffff9d9526d4a000 R14: ffff9d9526f4f340 R15: ffff9d9537654000
[   22.423726] FS:  0000000000000000(0000) GS:ffff9d953bc80000(0000) knlGS:0000000000000000
[   22.429898] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   22.434342] CR2: 000000c4206a9000 CR3: 00000001ea3fc002 CR4: 00000000001606e0
[   22.439645] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   22.444941] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   22.450342] Call Trace:
[   22.452509]  simple_strtoull+0x27/0x70
[   22.455572]  xenbus_transaction_start+0x31/0x50
[   22.459104]  netback_changed+0x76c/0xcc1 [xen_netfront]
[   22.463279]  ? find_watch+0x40/0x40
[   22.466156]  xenwatch_thread+0xb4/0x150
[   22.469309]  ? wait_woken+0x80/0x80
[   22.472198]  kthread+0x10e/0x130
[   22.474925]  ? kthread_park+0x80/0x80
[   22.477946]  ret_from_fork+0x35/0x40
[   22.480968] Modules linked in: xen_kbdfront xen_fbfront(+) xen_netfront xen_blkfront
[   22.486783] ---[ end trace a9222030a747c3f7 ]---
[   22.490424] RIP: 0010:_parse_integer_fixup_radix+0x6/0x60

The virt_rmb() is added in the 'true' path of test_reply(). The "while"
is changed to "do while" so that test_reply() is used as a read memory
barrier.

Signed-off-by: Dongli Zhang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Julien Grall <[email protected]>
Signed-off-by: Boris Ostrovsky <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 14, 2020
…abled

Commit cd02cf1 ("mm/hotplug: fix an imbalance with DEBUG_PAGEALLOC")
fixed memory hotplug with debug_pagealloc enabled, where onlining a page
goes through page freeing, which removes the direct mapping.  Some arches
don't like when the page is not mapped in the first place, so
generic_online_page() maps it first.  This is somewhat wasteful, but
better than special casing page freeing fast paths.

The commit however missed that DEBUG_PAGEALLOC configured doesn't mean
it's actually enabled.  One has to test debug_pagealloc_enabled() since
031bc57 ("mm/debug-pagealloc: make debug-pagealloc boottime
configurable"), or alternatively debug_pagealloc_enabled_static() since
8e57f8a ("mm, debug_pagealloc: don't rely on static keys too early"),
but this is not done.

As a result, a s390 kernel with DEBUG_PAGEALLOC configured but not enabled
will crash:

Unable to handle kernel pointer dereference in virtual kernel address space
Failing address: 0000000000000000 TEID: 0000000000000483
Fault in home space mode while using kernel ASCE.
AS:0000001ece13400b R2:000003fff7fd000b R3:000003fff7fcc007 S:000003fff7fd7000 P:000000000000013d
Oops: 0004 ilc:2 [#1] SMP
CPU: 1 PID: 26015 Comm: chmem Kdump: loaded Tainted: GX 5.3.18-5-default #1 SLE15-SP2 (unreleased)
Krnl PSW : 0704e00180000000 0000001ecd281b9e (__kernel_map_pages+0x166/0x188)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
Krnl GPRS: 0000000000000000 0000000000000800 0000400b00000000 0000000000000100
0000000000000001 0000000000000000 0000000000000002 0000000000000100
0000001ece139230 0000001ecdd98d40 0000400b00000100 0000000000000000
000003ffa17e4000 001fffe0114f7d08 0000001ecd4d93ea 001fffe0114f7b20
Krnl Code: 0000001ecd281b8e: ec17ffff00d8 ahik %r1,%r7,-1
0000001ecd281b94: ec111dbc0355 risbg %r1,%r1,29,188,3
>0000001ecd281b9e: 94fb5006 ni 6(%r5),251
0000001ecd281ba2: 41505008 la %r5,8(%r5)
0000001ecd281ba6: ec51fffc6064 cgrj %r5,%r1,6,1ecd281b9e
0000001ecd281bac: 1a07 ar %r0,%r7
0000001ecd281bae: ec03ff584076 crj %r0,%r3,4,1ecd281a5e
Call Trace:
[<0000001ecd281b9e>] __kernel_map_pages+0x166/0x188
[<0000001ecd4d9516>] online_pages_range+0xf6/0x128
[<0000001ecd2a8186>] walk_system_ram_range+0x7e/0xd8
[<0000001ecda28aae>] online_pages+0x2fe/0x3f0
[<0000001ecd7d02a6>] memory_subsys_online+0x8e/0xc0
[<0000001ecd7add42>] device_online+0x5a/0xc8
[<0000001ecd7d0430>] state_store+0x88/0x118
[<0000001ecd5b9f62>] kernfs_fop_write+0xc2/0x200
[<0000001ecd5064b6>] vfs_write+0x176/0x1e0
[<0000001ecd50676a>] ksys_write+0xa2/0x100
[<0000001ecda315d4>] system_call+0xd8/0x2c8

Fix this by checking debug_pagealloc_enabled_static() before calling
kernel_map_pages(). Backports for kernel before 5.5 should use
debug_pagealloc_enabled() instead. Also add comments.

Fixes: cd02cf1 ("mm/hotplug: fix an imbalance with DEBUG_PAGEALLOC")
Reported-by: Gerald Schaefer <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Vlastimil Babka <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Cc: <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Qian Cai <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 6, 2024
(1 << idx) of int is not desired when setting bits in unsigned long
overflowed_ctrs, use BIT() instead. This panic happens when running
'perf record -e branches' on sophgo sg2042.

[  273.311852] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000098
[  273.320851] Oops [#1]
[  273.323179] Modules linked in:
[  273.326303] CPU: 0 PID: 1475 Comm: perf Not tainted 6.6.0-rc3+ torvalds#9
[  273.332521] Hardware name: Sophgo Mango (DT)
[  273.336878] epc : riscv_pmu_ctr_get_width_mask+0x8/0x62
[  273.342291]  ra : pmu_sbi_ovf_handler+0x2e0/0x34e
[  273.347091] epc : ffffffff80aecd98 ra : ffffffff80aee056 sp : fffffff6e36928b0
[  273.354454]  gp : ffffffff821f82d0 tp : ffffffd90c353200 t0 : 0000002ade4f9978
[  273.361815]  t1 : 0000000000504d55 t2 : ffffffff8016cd8c s0 : fffffff6e3692a70
[  273.369180]  s1 : 0000000000000020 a0 : 0000000000000000 a1 : 00001a8e81800000
[  273.376540]  a2 : 0000003c00070198 a3 : 0000003c00db75a4 a4 : 0000000000000015
[  273.383901]  a5 : ffffffd7ff8804b0 a6 : 0000000000000015 a7 : 000000000000002a
[  273.391327]  s2 : 000000000000ffff s3 : 0000000000000000 s4 : ffffffd7ff8803b0
[  273.398773]  s5 : 0000000000504d55 s6 : ffffffd905069800 s7 : ffffffff821fe210
[  273.406139]  s8 : 000000007fffffff s9 : ffffffd7ff8803b0 s10: ffffffd903f29098
[  273.413660]  s11: 0000000080000000 t3 : 0000000000000003 t4 : ffffffff8017a0ca
[  273.421022]  t5 : ffffffff8023cfc2 t6 : ffffffd9040780e8
[  273.426437] status: 0000000200000100 badaddr: 0000000000000098 cause: 000000000000000d
[  273.434512] [<ffffffff80aecd98>] riscv_pmu_ctr_get_width_mask+0x8/0x62
[  273.441169] [<ffffffff80076bd8>] handle_percpu_devid_irq+0x98/0x1ee
[  273.447562] [<ffffffff80071158>] generic_handle_domain_irq+0x28/0x36
[  273.454151] [<ffffffff8047a99a>] riscv_intc_irq+0x36/0x4e
[  273.459659] [<ffffffff80c944de>] handle_riscv_irq+0x4a/0x74
[  273.465442] [<ffffffff80c94c48>] do_irq+0x62/0x92
[  273.470360] Code: 0420 60a2 6402 5529 0141 8082 0013 0000 0013 0000 (6d5c) b783
[  273.477921] ---[ end trace 0000000000000000 ]---
[  273.482630] Kernel panic - not syncing: Fatal exception in interrupt

Reviewed-by: Alexandre Ghiti <[email protected]>
Reviewed-by: Atish Patra <[email protected]>
Signed-off-by: Fei Wu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>
neuschaefer pushed a commit that referenced this issue Mar 6, 2024
For fiemap we recently stopped locking the target extent range for the
whole duration of the fiemap call, in order to avoid a deadlock in a
scenario where the fiemap buffer happens to be a memory mapped range of
the same file. This use case is very unlikely to be useful in practice but
it may be triggered by fuzz testing (syzbot, etc).

However by not locking the target extent range for the whole duration of
the fiemap call we can race with an ordered extent. This happens like
this:

1) The fiemap task finishes processing a file extent item that covers
   the file range [512K, 1M[, and that file extent item is the last item
   in the leaf currently being processed;

2) And ordered extent for the file range [768K, 2M[, in COW mode,
   completes (btrfs_finish_one_ordered()) and the file extent item
   covering the range [512K, 1M[ is trimmed to cover the range
   [512K, 768K[ and then a new file extent item for the range [768K, 2M[
   is inserted in the inode's subvolume tree;

3) The fiemap task calls fiemap_next_leaf_item(), which then calls
   btrfs_next_leaf() to find the next leaf / item. This finds that the
   the next key following the one we previously processed (its type is
   BTRFS_EXTENT_DATA_KEY and its offset is 512K), is the key corresponding
   to the new file extent item inserted by the ordered extent, which has
   a type of BTRFS_EXTENT_DATA_KEY and an offset of 768K;

4) Later the fiemap code ends up at emit_fiemap_extent() and triggers
   the warning:

      if (cache->offset + cache->len > offset) {
               WARN_ON(1);
               return -EINVAL;
      }

   Since we get 1M > 768K, because the previously emitted entry for the
   old extent covering the file range [512K, 1M[ ends at an offset that
   is greater than the new extent's start offset (768K). This makes fiemap
   fail with -EINVAL besides triggering the warning that produces a stack
   trace like the following:

     [1621.677651] ------------[ cut here ]------------
     [1621.677656] WARNING: CPU: 1 PID: 204366 at fs/btrfs/extent_io.c:2492 emit_fiemap_extent+0x84/0x90 [btrfs]
     [1621.677899] Modules linked in: btrfs blake2b_generic (...)
     [1621.677951] CPU: 1 PID: 204366 Comm: pool Not tainted 6.8.0-rc5-btrfs-next-151+ #1
     [1621.677954] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
     [1621.677956] RIP: 0010:emit_fiemap_extent+0x84/0x90 [btrfs]
     [1621.678033] Code: 2b 4c 89 63 (...)
     [1621.678035] RSP: 0018:ffffab16089ffd20 EFLAGS: 00010206
     [1621.678037] RAX: 00000000004fa000 RBX: ffffab16089ffe08 RCX: 0000000000009000
     [1621.678039] RDX: 00000000004f9000 RSI: 00000000004f1000 RDI: ffffab16089ffe90
     [1621.678040] RBP: 00000000004f9000 R08: 0000000000001000 R09: 0000000000000000
     [1621.678041] R10: 0000000000000000 R11: 0000000000001000 R12: 0000000041d78000
     [1621.678043] R13: 0000000000001000 R14: 0000000000000000 R15: ffff9434f0b17850
     [1621.678044] FS:  00007fa6e20006c0(0000) GS:ffff943bdfa40000(0000) knlGS:0000000000000000
     [1621.678046] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
     [1621.678048] CR2: 00007fa6b0801000 CR3: 000000012d404002 CR4: 0000000000370ef0
     [1621.678053] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
     [1621.678055] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
     [1621.678056] Call Trace:
     [1621.678074]  <TASK>
     [1621.678076]  ? __warn+0x80/0x130
     [1621.678082]  ? emit_fiemap_extent+0x84/0x90 [btrfs]
     [1621.678159]  ? report_bug+0x1f4/0x200
     [1621.678164]  ? handle_bug+0x42/0x70
     [1621.678167]  ? exc_invalid_op+0x14/0x70
     [1621.678170]  ? asm_exc_invalid_op+0x16/0x20
     [1621.678178]  ? emit_fiemap_extent+0x84/0x90 [btrfs]
     [1621.678253]  extent_fiemap+0x766/0xa30 [btrfs]
     [1621.678339]  btrfs_fiemap+0x45/0x80 [btrfs]
     [1621.678420]  do_vfs_ioctl+0x1e4/0x870
     [1621.678431]  __x64_sys_ioctl+0x6a/0xc0
     [1621.678434]  do_syscall_64+0x52/0x120
     [1621.678445]  entry_SYSCALL_64_after_hwframe+0x6e/0x76

There's also another case where before calling btrfs_next_leaf() we are
processing a hole or a prealloc extent and we had several delalloc ranges
within that hole or prealloc extent. In that case if the ordered extents
complete before we find the next key, we may end up finding an extent item
with an offset smaller than (or equals to) the offset in cache->offset.

So fix this by changing emit_fiemap_extent() to address these three
scenarios like this:

1) For the first case, steps listed above, adjust the length of the
   previously cached extent so that it does not overlap with the current
   extent, emit the previous one and cache the current file extent item;

2) For the second case where he had a hole or prealloc extent with
   multiple delalloc ranges inside the hole or prealloc extent's range,
   and the current file extent item has an offset that matches the offset
   in the fiemap cache, just discard what we have in the fiemap cache and
   assign the current file extent item to the cache, since it's more up
   to date;

3) For the third case where he had a hole or prealloc extent with
   multiple delalloc ranges inside the hole or prealloc extent's range
   and the offset of the file extent item we just found is smaller than
   what we have in the cache, just skip the current file extent item
   if its range end at or behind the cached extent's end, because we may
   have emitted (to the fiemap user space buffer) delalloc ranges that
   overlap with the current file extent item's range. If the file extent
   item's range goes beyond the end offset of the cached extent, just
   emit the cached extent and cache a subrange of the file extent item,
   that goes from the end offset of the cached extent to the end offset
   of the file extent item.

Dealing with those cases in those ways makes everything consistent by
reflecting the current state of file extent items in the btree and
without emitting extents that have overlapping ranges (which would be
confusing and violating expectations).

This issue could be triggered often with test case generic/561, and was
also hit and reported by Wang Yugui.

Reported-by: Wang Yugui <[email protected]>
Link: https://lore.kernel.org/linux-btrfs/[email protected]/
Fixes: b0ad381 ("btrfs: fix deadlock with fiemap and extent locking")
Reviewed-by: Josef Bacik <[email protected]>
Signed-off-by: Filipe Manana <[email protected]>
Signed-off-by: David Sterba <[email protected]>
neuschaefer added a commit that referenced this issue Mar 11, 2024
neuschaefer pushed a commit that referenced this issue Apr 1, 2024
There is this reported crash when experimenting with the lvm2 testsuite.
The list corruption is caused by the fact that the postsuspend and resume
methods were not paired correctly; there were two consecutive calls to the
origin_postsuspend function. The second call attempts to remove the
"hash_list" entry from a list, while it was already removed by the first
call.

Fix __dm_internal_resume so that it calls the preresume and resume
methods of the table's targets.

If a preresume method of some target fails, we are in a tricky situation.
We can't return an error because dm_internal_resume isn't supposed to
return errors. We can't return success, because then the "resume" and
"postsuspend" methods would not be paired correctly. So, we set the
DMF_SUSPENDED flag and we fake normal suspend - it may confuse userspace
tools, but it won't cause a kernel crash.

------------[ cut here ]------------
kernel BUG at lib/list_debug.c:56!
invalid opcode: 0000 [#1] PREEMPT SMP
CPU: 1 PID: 8343 Comm: dmsetup Not tainted 6.8.0-rc6 #4
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
RIP: 0010:__list_del_entry_valid_or_report+0x77/0xc0
<snip>
RSP: 0018:ffff8881b831bcc0 EFLAGS: 00010282
RAX: 000000000000004e RBX: ffff888143b6eb80 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff819053d0 RDI: 00000000ffffffff
RBP: ffff8881b83a3400 R08: 00000000fffeffff R09: 0000000000000058
R10: 0000000000000000 R11: ffffffff81a24080 R12: 0000000000000001
R13: ffff88814538e000 R14: ffff888143bc6dc0 R15: ffffffffa02e4bb0
FS:  00000000f7c0f780(0000) GS:ffff8893f0a40000(0000) knlGS:0000000000000000
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000057fb5000 CR3: 0000000143474000 CR4: 00000000000006b0
Call Trace:
 <TASK>
 ? die+0x2d/0x80
 ? do_trap+0xeb/0xf0
 ? __list_del_entry_valid_or_report+0x77/0xc0
 ? do_error_trap+0x60/0x80
 ? __list_del_entry_valid_or_report+0x77/0xc0
 ? exc_invalid_op+0x49/0x60
 ? __list_del_entry_valid_or_report+0x77/0xc0
 ? asm_exc_invalid_op+0x16/0x20
 ? table_deps+0x1b0/0x1b0 [dm_mod]
 ? __list_del_entry_valid_or_report+0x77/0xc0
 origin_postsuspend+0x1a/0x50 [dm_snapshot]
 dm_table_postsuspend_targets+0x34/0x50 [dm_mod]
 dm_suspend+0xd8/0xf0 [dm_mod]
 dev_suspend+0x1f2/0x2f0 [dm_mod]
 ? table_deps+0x1b0/0x1b0 [dm_mod]
 ctl_ioctl+0x300/0x5f0 [dm_mod]
 dm_compat_ctl_ioctl+0x7/0x10 [dm_mod]
 __x64_compat_sys_ioctl+0x104/0x170
 do_syscall_64+0x184/0x1b0
 entry_SYSCALL_64_after_hwframe+0x46/0x4e
RIP: 0033:0xf7e6aead
<snip>
---[ end trace 0000000000000000 ]---

Fixes: ffcc393 ("dm: enhance internal suspend and resume interface")
Signed-off-by: Mikulas Patocka <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>
neuschaefer pushed a commit that referenced this issue Apr 1, 2024
Use rbi->len instead of rcd->len for non-dataring packet.

Found issue:
  XDP_WARN: xdp_update_frame_from_buff(line:278): Driver BUG: missing reserved tailroom
  WARNING: CPU: 0 PID: 0 at net/core/xdp.c:586 xdp_warn+0xf/0x20
  CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W  O       6.5.1 #1
  RIP: 0010:xdp_warn+0xf/0x20
  ...
  ? xdp_warn+0xf/0x20
  xdp_do_redirect+0x15f/0x1c0
  vmxnet3_run_xdp+0x17a/0x400 [vmxnet3]
  vmxnet3_process_xdp+0xe4/0x760 [vmxnet3]
  ? vmxnet3_tq_tx_complete.isra.0+0x21e/0x2c0 [vmxnet3]
  vmxnet3_rq_rx_complete+0x7ad/0x1120 [vmxnet3]
  vmxnet3_poll_rx_only+0x2d/0xa0 [vmxnet3]
  __napi_poll+0x20/0x180
  net_rx_action+0x177/0x390

Reported-by: Martin Zaharinov <[email protected]>
Tested-by: Martin Zaharinov <[email protected]>
Link: https://lore.kernel.org/netdev/[email protected]/
Fixes: 54f00cc ("vmxnet3: Add XDP support.")
Signed-off-by: William Tu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>
neuschaefer pushed a commit that referenced this issue Apr 1, 2024
Fix race condition leading to system crash during EEH error handling

During EEH error recovery, the bnx2x driver's transmit timeout logic
could cause a race condition when handling reset tasks. The
bnx2x_tx_timeout() schedules reset tasks via bnx2x_sp_rtnl_task(),
which ultimately leads to bnx2x_nic_unload(). In bnx2x_nic_unload()
SGEs are freed using bnx2x_free_rx_sge_range(). However, this could
overlap with the EEH driver's attempt to reset the device using
bnx2x_io_slot_reset(), which also tries to free SGEs. This race
condition can result in system crashes due to accessing freed memory
locations in bnx2x_free_rx_sge()

799  static inline void bnx2x_free_rx_sge(struct bnx2x *bp,
800				struct bnx2x_fastpath *fp, u16 index)
801  {
802	struct sw_rx_page *sw_buf = &fp->rx_page_ring[index];
803     struct page *page = sw_buf->page;
....
where sw_buf was set to NULL after the call to dma_unmap_page()
by the preceding thread.

    EEH: Beginning: 'slot_reset'
    PCI 0011:01:00.0#10000: EEH: Invoking bnx2x->slot_reset()
    bnx2x: [bnx2x_io_slot_reset:14228(eth1)]IO slot reset initializing...
    bnx2x 0011:01:00.0: enabling device (0140 -> 0142)
    bnx2x: [bnx2x_io_slot_reset:14244(eth1)]IO slot reset --> driver unload
    Kernel attempted to read user page (0) - exploit attempt? (uid: 0)
    BUG: Kernel NULL pointer dereference on read at 0x00000000
    Faulting instruction address: 0xc0080000025065fc
    Oops: Kernel access of bad area, sig: 11 [#1]
    .....
    Call Trace:
    [c000000003c67a20] [c00800000250658c] bnx2x_io_slot_reset+0x204/0x610 [bnx2x] (unreliable)
    [c000000003c67af0] [c0000000000518a8] eeh_report_reset+0xb8/0xf0
    [c000000003c67b60] [c000000000052130] eeh_pe_report+0x180/0x550
    [c000000003c67c70] [c00000000005318c] eeh_handle_normal_event+0x84c/0xa60
    [c000000003c67d50] [c000000000053a84] eeh_event_handler+0xf4/0x170
    [c000000003c67da0] [c000000000194c58] kthread+0x1c8/0x1d0
    [c000000003c67e10] [c00000000000cf64] ret_from_kernel_thread+0x5c/0x64

To solve this issue, we need to verify page pool allocations before
freeing.

Fixes: 4cace67 ("bnx2x: Alloc 4k fragment for each rx ring buffer element")
Signed-off-by: Thinh Tran <[email protected]>
Reviewed-by: Jiri Pirko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
neuschaefer pushed a commit that referenced this issue Apr 1, 2024
The boot sequence evaluates CPUID information twice:

  1) During early boot

  2) When finalizing the early setup right before
     mitigations are selected and alternatives are patched.

In both cases the evaluation is stored in boot_cpu_data, but on UP the
copying of boot_cpu_data to the per CPU info of the boot CPU happens
between #1 and #2. So any update which happens in #2 is never propagated to
the per CPU info instance.

Consolidate the whole logic and copy boot_cpu_data right before applying
alternatives as that's the point where boot_cpu_data is in it's final
state and not supposed to change anymore.

This also removes the voodoo mb() from smp_prepare_cpus_common() which
had absolutely no purpose.

Fixes: 71eb489 ("x86/percpu: Cure per CPU madness on UP")
Reported-by: Guenter Roeck <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Borislav Petkov (AMD) <[email protected]>
Tested-by: Guenter Roeck <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
Its used from trace__run(), for the 'perf trace' live mode, i.e. its
strace-like, non-perf.data file processing mode, the most common one.

The trace__run() function will set trace->host using machine__new_host()
that is supposed to give a machine instance representing the running
machine, and since we'll use perf_env__arch_strerrno() to get the right
errno -> string table, we need to use machine->env, so initialize it in
machine__new_host().

Before the patch:

  (gdb) run trace --errno-summary -a sleep 1
  <SNIP>
   Summary of events:

   gvfs-afc-volume (3187), 2 events, 0.0%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     pselect6               1      0     0.000     0.000     0.000     0.000      0.00%

   GUsbEventThread (3519), 2 events, 0.0%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     poll                   1      0     0.000     0.000     0.000     0.000      0.00%
  <SNIP>
  Program received signal SIGSEGV, Segmentation fault.
  0x00000000005caba0 in perf_env__arch_strerrno (env=0x0, err=110) at util/env.c:478
  478		if (env->arch_strerrno == NULL)
  (gdb) bt
  #0  0x00000000005caba0 in perf_env__arch_strerrno (env=0x0, err=110) at util/env.c:478
  #1  0x00000000004b75d2 in thread__dump_stats (ttrace=0x14f58f0, trace=0x7fffffffa5b0, fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>) at builtin-trace.c:4673
  #2  0x00000000004b78bf in trace__fprintf_thread (fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>, thread=0x10fa0b0, trace=0x7fffffffa5b0) at builtin-trace.c:4708
  #3  0x00000000004b7ad9 in trace__fprintf_thread_summary (trace=0x7fffffffa5b0, fp=0x7ffff6ff74e0 <_IO_2_1_stderr_>) at builtin-trace.c:4747
  #4  0x00000000004b656e in trace__run (trace=0x7fffffffa5b0, argc=2, argv=0x7fffffffde60) at builtin-trace.c:4456
  #5  0x00000000004ba43e in cmd_trace (argc=2, argv=0x7fffffffde60) at builtin-trace.c:5487
  #6  0x00000000004c0414 in run_builtin (p=0xec3068 <commands+648>, argc=5, argv=0x7fffffffde60) at perf.c:351
  #7  0x00000000004c06bb in handle_internal_command (argc=5, argv=0x7fffffffde60) at perf.c:404
  #8  0x00000000004c0814 in run_argv (argcp=0x7fffffffdc4c, argv=0x7fffffffdc40) at perf.c:448
  torvalds#9  0x00000000004c0b5d in main (argc=5, argv=0x7fffffffde60) at perf.c:560
  (gdb)

After:

  root@number:~# perf trace -a --errno-summary sleep 1
  <SNIP>
     pw-data-loop (2685), 1410 events, 16.0%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     epoll_wait           188      0   983.428     0.000     5.231    15.595      8.68%
     ioctl                 94      0     0.811     0.004     0.009     0.016      2.82%
     read                 188      0     0.322     0.001     0.002     0.006      5.15%
     write                141      0     0.280     0.001     0.002     0.018      8.39%
     timerfd_settime       94      0     0.138     0.001     0.001     0.007      6.47%

   gnome-control-c (179406), 1848 events, 20.9%

     syscall            calls  errors  total       min       avg       max       stddev
                                       (msec)    (msec)    (msec)    (msec)        (%)
     --------------- --------  ------ -------- --------- --------- ---------     ------
     poll                 222      0   959.577     0.000     4.322    21.414     11.40%
     recvmsg              150      0     0.539     0.001     0.004     0.013      5.12%
     write                300      0     0.442     0.001     0.001     0.007      3.29%
     read                 150      0     0.183     0.001     0.001     0.009      5.53%
     getpid               102      0     0.101     0.000     0.001     0.008      7.82%

  root@number:~#

Fixes: 54373b5 ("perf env: Introduce perf_env__arch_strerrno()")
Reported-by: Veronika Molnarova <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Acked-by: Veronika Molnarova <[email protected]>
Acked-by: Michael Petlan <[email protected]>
Tested-by: Michael Petlan <[email protected]>
Link: https://lore.kernel.org/r/Z0XffUgNSv_9OjOi@x1
Signed-off-by: Namhyung Kim <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
Similar to commit 65c4c94 ("usb: typec: ucsi: Fix a missing bits to
bytes conversion in ucsi_init()"), there was a missing conversion from
bits to bytes. Here the outcome is worse though: since the value is
lower than UCSI_MAX_DATA_LENGTH, instead of bailing out with an error,
it writes past the buffer size.

The error is then seen in other places like below:

	Oops: general protection fault, probably for non-canonical address 0x891e812cd0ed968: 0000 [#1] PREEMPT SMP NOPTI
	CPU: 3 UID: 110 PID: 906 Comm: prometheus-node Not tainted 6.13.0-rc1-xe #1
	Hardware name: Intel Corporation Lunar Lake Client Platform/LNL-M LP5 RVP1, BIOS LNLMFWI1.R00.3222.D84.2410171025 10/17/2024
	RIP: 0010:power_supply_get_property+0x3e/0xe0
	Code: 85 c0 7e 4f 4c 8b 07 89 f3 49 89 d4 49 8b 48 20 48 85 c9 74 72 49 8b 70 18 31 d2 31 c0 eb 0b 83 c2 01 48 63 c2 48 39 c8 73 5d <3b> 1c 86 75 f0 49 8b 40 28 4c 89 e2 89 de ff d0 0f 1f 00 5b 41 5c
	RSP: 0018:ffffc900017dfa50 EFLAGS: 00010246
	RAX: 0000000000000000 RBX: 0000000000000011 RCX: c963b02c06092008
	RDX: 0000000000000000 RSI: 0891e812cd0ed968 RDI: ffff888121dd6800
	RBP: ffffc900017dfa68 R08: ffff88810a4024b8 R09: 0000000000000000
	R10: 0000000000000000 R11: 0000000000000000 R12: ffffc900017dfa78
	R13: ffff888121dd6800 R14: ffff888138ad2c00 R15: ffff88810c57c528
	FS:  00007713a2ffd6c0(0000) GS:ffff88846f380000(0000) knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
	CR2: 000000c0004b1000 CR3: 0000000121ce8003 CR4: 0000000000f72ef0
	DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
	DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7: 0000000000000400
	PKRU: 55555554
	Call Trace:
	 <TASK>
	 ? show_regs+0x6c/0x80
	 ? die_addr+0x37/0xa0
	 ? exc_general_protection+0x1c1/0x440
	 ? asm_exc_general_protection+0x27/0x30
	 ? power_supply_get_property+0x3e/0xe0
	 power_supply_hwmon_read+0x50/0xe0
	 hwmon_attr_show+0x46/0x170
	 dev_attr_show+0x1a/0x70
	 sysfs_kf_seq_show+0xaa/0x120
	 kernfs_seq_show+0x41/0x60

Just use the buffer size as argument to fix it.

Fixes: 226ff2e ("usb: typec: ucsi: Convert connector specific commands to bitmaps")
Signed-off-by: Lucas De Marchi <[email protected]>
Reviewed-by: Thomas Weißschuh <[email protected]>
Reviewed-by: Sebastian Reichel <[email protected]>
Reported-by: Chaitanya Kumar Borah <[email protected]>
Closes: https://lore.kernel.org/all/SJ1PR11MB6129CCD82CD78D8EE6E27EF4B9362@SJ1PR11MB6129.namprd11.prod.outlook.com/
Suggested-by: Thomas Weißschuh <[email protected]>
Reviewed-by: Heikki Krogerus <[email protected]>
Tested-by: Chaitanya Kumar Borah <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
syzbot found [1] that after blamed commit, ub->ubsock->sk
was NULL when attempting the atomic_dec() :

atomic_dec(&tipc_net(sock_net(ub->ubsock->sk))->wq_count);

Fix this by caching the tipc_net pointer.

[1]

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 0 UID: 0 PID: 5896 Comm: kworker/0:3 Not tainted 6.13.0-rc1-next-20241203-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events cleanup_bearer
 RIP: 0010:read_pnet include/net/net_namespace.h:387 [inline]
 RIP: 0010:sock_net include/net/sock.h:655 [inline]
 RIP: 0010:cleanup_bearer+0x1f7/0x280 net/tipc/udp_media.c:820
Code: 18 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 3c f7 99 f6 48 8b 1b 48 83 c3 30 e8 f0 e4 60 00 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 1a f7 99 f6 49 83 c7 e8 48 8b 1b
RSP: 0018:ffffc9000410fb70 EFLAGS: 00010206
RAX: 0000000000000006 RBX: 0000000000000030 RCX: ffff88802fe45a00
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffc9000410f900
RBP: ffff88807e1f0908 R08: ffffc9000410f907 R09: 1ffff92000821f20
R10: dffffc0000000000 R11: fffff52000821f21 R12: ffff888031d19980
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff88807e1f0918
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556ca050b000 CR3: 0000000031c0c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Fixes: 6a2fa13 ("tipc: Fix use-after-free of kernel socket in cleanup_bearer().")
Reported-by: [email protected]
Closes: https://lore.kernel.org/netdev/[email protected]/T/#u
Signed-off-by: Eric Dumazet <[email protected]>
Reviewed-by: Kuniyuki Iwashima <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
If the FW log context memory is retained after FW reset, the existing
code is not handling the condition correctly and zeroes out the data
structures.  This potentially will cause a division by zero crash
when the user runs ethtool -w.  The last_type is also not set
correctly when the context memory is retained.  This will cause errors
because the last_type signals to the FW that all context memory types
have been configured.

Oops: divide error: 0000 1 PREEMPT SMP NOPTI
CPU: 53 UID: 0 PID: 7019 Comm: ethtool Kdump: loaded Tainted: G           OE      6.12.0-rc7+ #1
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: Supermicro SYS-621C-TN12R/X13DDW-A, BIOS 1.4 08/10/2023
RIP: 0010:__bnxt_copy_ctx_mem.constprop.0.isra.0+0x86/0x160 [bnxt_en]
Code: 0a 31 d2 4c 89 6c 24 10 45 8b a5 fc df ff ff 4c 8b 74 24 20 31 db 66 89 44 24 06 48 63 c5 c1 e5 09 4c 0f af e0 48 8b 44 24 30 <49> f7 f4 4c 89 64 24 08 48 63 c5 4d 89 ec 31 ed 48 89 44 24 18 49
RSP: 0018:ff480591603d78b8 EFLAGS: 00010206
RAX: 0000000000100000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ff23959e46740000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000100000 R09: ff23959e46740000
R10: ff480591603d7a18 R11: 0000000000000010 R12: 0000000000000000
R13: ff23959e46742008 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f04227c1740(0000) GS:ff2395adbf680000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f04225b33a5 CR3: 000000108b9a4001 CR4: 0000000000773ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 ? die+0x33/0x90
 ? do_trap+0xd9/0x100
 ? __bnxt_copy_ctx_mem.constprop.0.isra.0+0x86/0x160 [bnxt_en]
 ? do_error_trap+0x65/0x80
 ? __bnxt_copy_ctx_mem.constprop.0.isra.0+0x86/0x160 [bnxt_en]
 ? exc_divide_error+0x36/0x50
 ? __bnxt_copy_ctx_mem.constprop.0.isra.0+0x86/0x160 [bnxt_en]
 ? asm_exc_divide_error+0x16/0x20
 ? __bnxt_copy_ctx_mem.constprop.0.isra.0+0x86/0x160 [bnxt_en]
 ? __bnxt_copy_ctx_mem.constprop.0.isra.0+0xda/0x160 [bnxt_en]
 bnxt_get_ctx_coredump.constprop.0+0x1ed/0x390 [bnxt_en]
 ? __memcg_slab_post_alloc_hook+0x21c/0x3c0
 ? __bnxt_get_coredump+0x473/0x4b0 [bnxt_en]
 __bnxt_get_coredump+0x473/0x4b0 [bnxt_en]
 ? security_file_alloc+0x74/0xe0
 ? cred_has_capability.isra.0+0x78/0x120
 bnxt_get_coredump_length+0x4b/0xf0 [bnxt_en]
 bnxt_get_dump_flag+0x40/0x60 [bnxt_en]
 __dev_ethtool+0x17e4/0x1fc0
 ? syscall_exit_to_user_mode+0xc/0x1d0
 ? do_syscall_64+0x85/0x150
 ? unmap_page_range+0x299/0x4b0
 ? vma_interval_tree_remove+0x215/0x2c0
 ? __kmalloc_cache_noprof+0x10a/0x300
 dev_ethtool+0xa8/0x170
 dev_ioctl+0x1b5/0x580
 ? sk_ioctl+0x4a/0x110
 sock_do_ioctl+0xab/0xf0
 sock_ioctl+0x1ca/0x2e0
 __x64_sys_ioctl+0x87/0xc0
 do_syscall_64+0x79/0x150

Fixes: 24d694a ("bnxt_en: Allocate backing store memory for FW trace logs")
Signed-off-by: Hongguang Gao <[email protected]>
Signed-off-by: Michael Chan <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
It is unclear if net/lapb code is supposed to be ready for 8021q.

We can at least avoid crashes like the following :

skbuff: skb_under_panic: text:ffffffff8aabe1f6 len:24 put:20 head:ffff88802824a400 data:ffff88802824a3fe tail:0x16 end:0x140 dev:nr0.2
------------[ cut here ]------------
 kernel BUG at net/core/skbuff.c:206 !
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 1 UID: 0 PID: 5508 Comm: dhcpcd Not tainted 6.12.0-rc7-syzkaller-00144-g66418447d27b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
 RIP: 0010:skb_panic net/core/skbuff.c:206 [inline]
 RIP: 0010:skb_under_panic+0x14b/0x150 net/core/skbuff.c:216
Code: 0d 8d 48 c7 c6 2e 9e 29 8e 48 8b 54 24 08 8b 0c 24 44 8b 44 24 04 4d 89 e9 50 41 54 41 57 41 56 e8 1a 6f 37 02 48 83 c4 20 90 <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3
RSP: 0018:ffffc90002ddf638 EFLAGS: 00010282
RAX: 0000000000000086 RBX: dffffc0000000000 RCX: 7a24750e538ff600
RDX: 0000000000000000 RSI: 0000000000000201 RDI: 0000000000000000
RBP: ffff888034a86650 R08: ffffffff8174b13c R09: 1ffff920005bbe60
R10: dffffc0000000000 R11: fffff520005bbe61 R12: 0000000000000140
R13: ffff88802824a400 R14: ffff88802824a3fe R15: 0000000000000016
FS:  00007f2a5990d740(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2631fd CR3: 0000000029504000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
  skb_push+0xe5/0x100 net/core/skbuff.c:2636
  nr_header+0x36/0x320 net/netrom/nr_dev.c:69
  dev_hard_header include/linux/netdevice.h:3148 [inline]
  vlan_dev_hard_header+0x359/0x480 net/8021q/vlan_dev.c:83
  dev_hard_header include/linux/netdevice.h:3148 [inline]
  lapbeth_data_transmit+0x1f6/0x2a0 drivers/net/wan/lapbether.c:257
  lapb_data_transmit+0x91/0xb0 net/lapb/lapb_iface.c:447
  lapb_transmit_buffer+0x168/0x1f0 net/lapb/lapb_out.c:149
 lapb_establish_data_link+0x84/0xd0
 lapb_device_event+0x4e0/0x670
  notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
 __dev_notify_flags+0x207/0x400
  dev_change_flags+0xf0/0x1a0 net/core/dev.c:8922
  devinet_ioctl+0xa4e/0x1aa0 net/ipv4/devinet.c:1188
  inet_ioctl+0x3d7/0x4f0 net/ipv4/af_inet.c:1003
  sock_do_ioctl+0x158/0x460 net/socket.c:1227
  sock_ioctl+0x626/0x8e0 net/socket.c:1346
  vfs_ioctl fs/ioctl.c:51 [inline]
  __do_sys_ioctl fs/ioctl.c:907 [inline]
  __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: [email protected]
Closes: https://lore.kernel.org/netdev/[email protected]/T/#u
Signed-off-by: Eric Dumazet <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
If the KVP (or VSS) daemon starts before the VMBus channel's ringbuffer is
fully initialized, we can hit the panic below:

hv_utils: Registering HyperV Utility Driver
hv_vmbus: registering driver hv_utils
...
BUG: kernel NULL pointer dereference, address: 0000000000000000
CPU: 44 UID: 0 PID: 2552 Comm: hv_kvp_daemon Tainted: G E 6.11.0-rc3+ #1
RIP: 0010:hv_pkt_iter_first+0x12/0xd0
Call Trace:
...
 vmbus_recvpacket
 hv_kvp_onchannelcallback
 vmbus_on_event
 tasklet_action_common
 tasklet_action
 handle_softirqs
 irq_exit_rcu
 sysvec_hyperv_stimer0
 </IRQ>
 <TASK>
 asm_sysvec_hyperv_stimer0
...
 kvp_register_done
 hvt_op_read
 vfs_read
 ksys_read
 __x64_sys_read

This can happen because the KVP/VSS channel callback can be invoked
even before the channel is fully opened:
1) as soon as hv_kvp_init() -> hvutil_transport_init() creates
/dev/vmbus/hv_kvp, the kvp daemon can open the device file immediately and
register itself to the driver by writing a message KVP_OP_REGISTER1 to the
file (which is handled by kvp_on_msg() ->kvp_handle_handshake()) and
reading the file for the driver's response, which is handled by
hvt_op_read(), which calls hvt->on_read(), i.e. kvp_register_done().

2) the problem with kvp_register_done() is that it can cause the
channel callback to be called even before the channel is fully opened,
and when the channel callback is starting to run, util_probe()->
vmbus_open() may have not initialized the ringbuffer yet, so the
callback can hit the panic of NULL pointer dereference.

To reproduce the panic consistently, we can add a "ssleep(10)" for KVP in
__vmbus_open(), just before the first hv_ringbuffer_init(), and then we
unload and reload the driver hv_utils, and run the daemon manually within
the 10 seconds.

Fix the panic by reordering the steps in util_probe() so the char dev
entry used by the KVP or VSS daemon is not created until after
vmbus_open() has completed. This reordering prevents the race condition
from happening.

Reported-by: Dexuan Cui <[email protected]>
Fixes: e0fa3e5 ("Drivers: hv: utils: fix a race on userspace daemons registration")
Cc: [email protected]
Signed-off-by: Michael Kelley <[email protected]>
Acked-by: Wei Liu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Wei Liu <[email protected]>
Message-ID: <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
Move setting irq_chip.name from probe() function to the initialization
of "irq_chip" struct in order to fix vGPIO driver crash during bootup.

Crash was caused by unauthorized modification of irq_chip.name field
where irq_chip struct was initialized as const.

This behavior is a consequence of suboptimal implementation of
gpio_irq_chip_set_chip(), which should be changed to avoid
casting away const qualifier.

Crash log:
BUG: unable to handle page fault for address: ffffffffc0ba81c0
/#PF: supervisor write access in kernel mode
/#PF: error_code(0x0003) - permissions violation
CPU: 33 UID: 0 PID: 1075 Comm: systemd-udevd Not tainted 6.12.0-rc6-00077-g2e1b3cc9d7f7 #1
Hardware name: Intel Corporation Kaseyville RP/Kaseyville RP, BIOS KVLDCRB1.PGS.0026.D73.2410081258 10/08/2024
RIP: 0010:gnr_gpio_probe+0x171/0x220 [gpio_graniterapids]

Cc: [email protected]
Signed-off-by: Alan Borzeszkowski <[email protected]>
Signed-off-by: Mika Westerberg <[email protected]>
Acked-by: Andy Shevchenko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
When virtnet_close is followed by virtnet_open, some TX completions can
possibly remain unconsumed, until they are finally processed during the
first NAPI poll after the netdev_tx_reset_queue(), resulting in a crash
[1]. Commit b96ed2c ("virtio_net: move netdev_tx_reset_queue() call
before RX napi enable") was not sufficient to eliminate all BQL crash
cases for virtio-net.

This issue can be reproduced with the latest net-next master by running:
`while :; do ip l set DEV down; ip l set DEV up; done` under heavy network
TX load from inside the machine.

netdev_tx_reset_queue() can actually be dropped from virtnet_open path;
the device is not stopped in any case. For BQL core part, it's just like
traffic nearly ceases to exist for some period. For stall detector added
to BQL, even if virtnet_close could somehow lead to some TX completions
delayed for long, followed by virtnet_open, we can just take it as stall
as mentioned in commit 6025b91 ("net: dqs: add NIC stall detector
based on BQL"). Note also that users can still reset stall_max via sysfs.

So, drop netdev_tx_reset_queue() from virtnet_enable_queue_pair(). This
eliminates the BQL crashes. As a result, netdev_tx_reset_queue() is now
explicitly required in freeze/restore path. This patch adds it to
immediately after free_unused_bufs(), following the rule of thumb:
netdev_tx_reset_queue() should follow any SKB freeing not followed by
netdev_tx_completed_queue(). This seems the most consistent and
streamlined approach, and now netdev_tx_reset_queue() runs whenever
free_unused_bufs() is done.

[1]:
------------[ cut here ]------------
kernel BUG at lib/dynamic_queue_limits.c:99!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 7 UID: 0 PID: 1598 Comm: ip Tainted: G    N 6.12.0net-next_main+ #2
Tainted: [N]=TEST
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), \
BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
RIP: 0010:dql_completed+0x26b/0x290
Code: b7 c2 49 89 e9 44 89 da 89 c6 4c 89 d7 e8 ed 17 47 00 58 65 ff 0d
4d 27 90 7e 0f 85 fd fe ff ff e8 ea 53 8d ff e9 f3 fe ff ff <0f> 0b 01
d2 44 89 d1 29 d1 ba 00 00 00 00 0f 48 ca e9 28 ff ff ff
RSP: 0018:ffffc900002b0d08 EFLAGS: 00010297
RAX: 0000000000000000 RBX: ffff888102398c80 RCX: 0000000080190009
RDX: 0000000000000000 RSI: 000000000000006a RDI: 0000000000000000
RBP: ffff888102398c00 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000000ca R11: 0000000000015681 R12: 0000000000000001
R13: ffffc900002b0d68 R14: ffff88811115e000 R15: ffff8881107aca40
FS:  00007f41ded69500(0000) GS:ffff888667dc0000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556ccc2dc1a0 CR3: 0000000104fd8003 CR4: 0000000000772ef0
PKRU: 55555554
Call Trace:
 <IRQ>
 ? die+0x32/0x80
 ? do_trap+0xd9/0x100
 ? dql_completed+0x26b/0x290
 ? dql_completed+0x26b/0x290
 ? do_error_trap+0x6d/0xb0
 ? dql_completed+0x26b/0x290
 ? exc_invalid_op+0x4c/0x60
 ? dql_completed+0x26b/0x290
 ? asm_exc_invalid_op+0x16/0x20
 ? dql_completed+0x26b/0x290
 __free_old_xmit+0xff/0x170 [virtio_net]
 free_old_xmit+0x54/0xc0 [virtio_net]
 virtnet_poll+0xf4/0xe30 [virtio_net]
 ? __update_load_avg_cfs_rq+0x264/0x2d0
 ? update_curr+0x35/0x260
 ? reweight_entity+0x1be/0x260
 __napi_poll.constprop.0+0x28/0x1c0
 net_rx_action+0x329/0x420
 ? enqueue_hrtimer+0x35/0x90
 ? trace_hardirqs_on+0x1d/0x80
 ? kvm_sched_clock_read+0xd/0x20
 ? sched_clock+0xc/0x30
 ? kvm_sched_clock_read+0xd/0x20
 ? sched_clock+0xc/0x30
 ? sched_clock_cpu+0xd/0x1a0
 handle_softirqs+0x138/0x3e0
 do_softirq.part.0+0x89/0xc0
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0xa7/0xb0
 virtnet_open+0xc8/0x310 [virtio_net]
 __dev_open+0xfa/0x1b0
 __dev_change_flags+0x1de/0x250
 dev_change_flags+0x22/0x60
 do_setlink.isra.0+0x2df/0x10b0
 ? rtnetlink_rcv_msg+0x34f/0x3f0
 ? netlink_rcv_skb+0x54/0x100
 ? netlink_unicast+0x23e/0x390
 ? netlink_sendmsg+0x21e/0x490
 ? ____sys_sendmsg+0x31b/0x350
 ? avc_has_perm_noaudit+0x67/0xf0
 ? cred_has_capability.isra.0+0x75/0x110
 ? __nla_validate_parse+0x5f/0xee0
 ? __pfx___probestub_irq_enable+0x3/0x10
 ? __create_object+0x5e/0x90
 ? security_capable+0x3b/0x70
 rtnl_newlink+0x784/0xaf0
 ? avc_has_perm_noaudit+0x67/0xf0
 ? cred_has_capability.isra.0+0x75/0x110
 ? stack_depot_save_flags+0x24/0x6d0
 ? __pfx_rtnl_newlink+0x10/0x10
 rtnetlink_rcv_msg+0x34f/0x3f0
 ? do_syscall_64+0x6c/0x180
 ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
 ? __pfx_rtnetlink_rcv_msg+0x10/0x10
 netlink_rcv_skb+0x54/0x100
 netlink_unicast+0x23e/0x390
 netlink_sendmsg+0x21e/0x490
 ____sys_sendmsg+0x31b/0x350
 ? copy_msghdr_from_user+0x6d/0xa0
 ___sys_sendmsg+0x86/0xd0
 ? __pte_offset_map+0x17/0x160
 ? preempt_count_add+0x69/0xa0
 ? __call_rcu_common.constprop.0+0x147/0x610
 ? preempt_count_add+0x69/0xa0
 ? preempt_count_add+0x69/0xa0
 ? _raw_spin_trylock+0x13/0x60
 ? trace_hardirqs_on+0x1d/0x80
 __sys_sendmsg+0x66/0xc0
 do_syscall_64+0x6c/0x180
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f41defe5b34
Code: 15 e1 12 0f 00 f7 d8 64 89 02 b8 ff ff ff ff eb bf 0f 1f 44 00 00
f3 0f 1e fa 80 3d 35 95 0f 00 00 74 13 b8 2e 00 00 00 0f 05 <48> 3d 00
f0 ff ff 77 4c c3 0f 1f 00 55 48 89 e5 48 83 ec 20 89 55
RSP: 002b:00007ffe5336ecc8 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f41defe5b34
RDX: 0000000000000000 RSI: 00007ffe5336ed30 RDI: 0000000000000003
RBP: 00007ffe5336eda0 R08: 0000000000000010 R09: 0000000000000001
R10: 00007ffe5336f6f9 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000067452259 R14: 0000556ccc28b040 R15: 0000000000000000
 </TASK>
[...]

Fixes: c8bd1f7 ("virtio_net: add support for Byte Queue Limits")
Cc: <[email protected]> # v6.11+
Signed-off-by: Koichiro Den <[email protected]>
Acked-by: Jason Wang <[email protected]>
Reviewed-by: Xuan Zhuo <[email protected]>
[ pabeni: trimmed possibly troublesome separator ]
Signed-off-by: Paolo Abeni <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
…nts'

Koichiro Den says:

====================
virtio_net: correct netdev_tx_reset_queue() invocation points

When virtnet_close is followed by virtnet_open, some TX completions can
possibly remain unconsumed, until they are finally processed during the
first NAPI poll after the netdev_tx_reset_queue(), resulting in a crash
[1]. Commit b96ed2c ("virtio_net: move netdev_tx_reset_queue() call
before RX napi enable") was not sufficient to eliminate all BQL crash
scenarios for virtio-net.

This issue can be reproduced with the latest net-next master by running:
`while :; do ip l set DEV down; ip l set DEV up; done` under heavy network
TX load from inside the machine.

This patch series resolves the issue and also addresses similar existing
problems:

(a). Drop netdev_tx_reset_queue() from open/close path. This eliminates the
     BQL crashes due to the problematic open/close path.

(b). As a result of (a), netdev_tx_reset_queue() is now explicitly required
     in freeze/restore path. Add netdev_tx_reset_queue() immediately after
     free_unused_bufs() invocation.

(c). Fix missing resetting in virtnet_tx_resize().
     virtnet_tx_resize() has lacked proper resetting since commit
     c8bd1f7 ("virtio_net: add support for Byte Queue Limits").

(d). Fix missing resetting in the XDP_SETUP_XSK_POOL path.
     Similar to (c), this path lacked proper resetting. Call
     netdev_tx_reset_queue() when virtqueue_reset() has actually recycled
     unused buffers.

This patch series consists of six commits:
  [1/6]: Resolves (a) and (b).                      # also -stable 6.11.y
  [2/6]: Minor fix to make [4/6] streamlined.
  [3/6]: Prerequisite for (c).                      # also -stable 6.11.y
  [4/6]: Resolves (c) (incl. Prerequisite for (d))  # also -stable 6.11.y
  [5/6]: Preresuisite for (d).
  [6/6]: Resolves (d).

Changes for v4:
  - move netdev_tx_reset_queue() out of free_unused_bufs()
  - submit to net, not net-next
Changes for v3:
  - replace 'flushed' argument with 'recycle_done'
Changes for v2:
  - add tx queue resetting for (b) to (d) above

v3: https://lore.kernel.org/all/[email protected]/
v2: https://lore.kernel.org/all/[email protected]/
v1: https://lore.kernel.org/all/[email protected]/

[1]:
------------[ cut here ]------------
kernel BUG at lib/dynamic_queue_limits.c:99!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 7 UID: 0 PID: 1598 Comm: ip Tainted: G    N 6.12.0net-next_main+ #2
Tainted: [N]=TEST
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), \
BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
RIP: 0010:dql_completed+0x26b/0x290
Code: b7 c2 49 89 e9 44 89 da 89 c6 4c 89 d7 e8 ed 17 47 00 58 65 ff 0d
4d 27 90 7e 0f 85 fd fe ff ff e8 ea 53 8d ff e9 f3 fe ff ff <0f> 0b 01
d2 44 89 d1 29 d1 ba 00 00 00 00 0f 48 ca e9 28 ff ff ff
RSP: 0018:ffffc900002b0d08 EFLAGS: 00010297
RAX: 0000000000000000 RBX: ffff888102398c80 RCX: 0000000080190009
RDX: 0000000000000000 RSI: 000000000000006a RDI: 0000000000000000
RBP: ffff888102398c00 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000000ca R11: 0000000000015681 R12: 0000000000000001
R13: ffffc900002b0d68 R14: ffff88811115e000 R15: ffff8881107aca40
FS:  00007f41ded69500(0000) GS:ffff888667dc0000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556ccc2dc1a0 CR3: 0000000104fd8003 CR4: 0000000000772ef0
PKRU: 55555554
Call Trace:
 <IRQ>
 ? die+0x32/0x80
 ? do_trap+0xd9/0x100
 ? dql_completed+0x26b/0x290
 ? dql_completed+0x26b/0x290
 ? do_error_trap+0x6d/0xb0
 ? dql_completed+0x26b/0x290
 ? exc_invalid_op+0x4c/0x60
 ? dql_completed+0x26b/0x290
 ? asm_exc_invalid_op+0x16/0x20
 ? dql_completed+0x26b/0x290
 __free_old_xmit+0xff/0x170 [virtio_net]
 free_old_xmit+0x54/0xc0 [virtio_net]
 virtnet_poll+0xf4/0xe30 [virtio_net]
 ? __update_load_avg_cfs_rq+0x264/0x2d0
 ? update_curr+0x35/0x260
 ? reweight_entity+0x1be/0x260
 __napi_poll.constprop.0+0x28/0x1c0
 net_rx_action+0x329/0x420
 ? enqueue_hrtimer+0x35/0x90
 ? trace_hardirqs_on+0x1d/0x80
 ? kvm_sched_clock_read+0xd/0x20
 ? sched_clock+0xc/0x30
 ? kvm_sched_clock_read+0xd/0x20
 ? sched_clock+0xc/0x30
 ? sched_clock_cpu+0xd/0x1a0
 handle_softirqs+0x138/0x3e0
 do_softirq.part.0+0x89/0xc0
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0xa7/0xb0
 virtnet_open+0xc8/0x310 [virtio_net]
 __dev_open+0xfa/0x1b0
 __dev_change_flags+0x1de/0x250
 dev_change_flags+0x22/0x60
 do_setlink.isra.0+0x2df/0x10b0
 ? rtnetlink_rcv_msg+0x34f/0x3f0
 ? netlink_rcv_skb+0x54/0x100
 ? netlink_unicast+0x23e/0x390
 ? netlink_sendmsg+0x21e/0x490
 ? ____sys_sendmsg+0x31b/0x350
 ? avc_has_perm_noaudit+0x67/0xf0
 ? cred_has_capability.isra.0+0x75/0x110
 ? __nla_validate_parse+0x5f/0xee0
 ? __pfx___probestub_irq_enable+0x3/0x10
 ? __create_object+0x5e/0x90
 ? security_capable+0x3b/0x7�[I0
 rtnl_newlink+0x784/0xaf0
 ? avc_has_perm_noaudit+0x67/0xf0
 ? cred_has_capability.isra.0+0x75/0x110
 ? stack_depot_save_flags+0x24/0x6d0
 ? __pfx_rtnl_newlink+0x10/0x10
 rtnetlink_rcv_msg+0x34f/0x3f0
 ? do_syscall_64+0x6c/0x180
 ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
 ? __pfx_rtnetlink_rcv_msg+0x10/0x10
 netlink_rcv_skb+0x54/0x100
 netlink_unicast+0x23e/0x390
 netlink_sendmsg+0x21e/0x490
 ____sys_sendmsg+0x31b/0x350
 ? copy_msghdr_from_user+0x6d/0xa0
 ___sys_sendmsg+0x86/0xd0
 ? __pte_offset_map+0x17/0x160
 ? preempt_count_add+0x69/0xa0
 ? __call_rcu_common.constprop.0+0x147/0x610
 ? preempt_count_add+0x69/0xa0
 ? preempt_count_add+0x69/0xa0
 ? _raw_spin_trylock+0x13/0x60
 ? trace_hardirqs_on+0x1d/0x80
 __sys_sendmsg+0x66/0xc0
 do_syscall_64+0x6c/0x180
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f41defe5b34
Code: 15 e1 12 0f 00 f7 d8 64 89 02 b8 ff ff ff ff eb bf 0f 1f 44 00 00
f3 0f 1e fa 80 3d 35 95 0f 00 00 74 13 b8 2e 00 00 00 0f 05 <48> 3d 00
f0 ff ff 77 4c c3 0f 1f 00 55 48 89 e5 48 83 ec 20 89 55
RSP: 002b:00007ffe5336ecc8 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f41defe5b34
RDX: 0000000000000000 RSI: 00007ffe5336ed30 RDI: 0000000000000003
RBP: 00007ffe5336eda0 R08: 0000000000000010 R09: 0000000000000001
R10: 00007ffe5336f6f9 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000067452259 R14: 0000556ccc28b040 R15: 0000000000000000
 </TASK>
[...]
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
flush_tlb_kernel_range() may use IPIs to flush the TLBs of all the
cores, which triggers the following warning when the irqs are disabled:

[    3.455330] WARNING: CPU: 1 PID: 0 at kernel/smp.c:815 smp_call_function_many_cond+0x452/0x520
[    3.456647] Modules linked in:
[    3.457218] CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.12.0-rc7-00010-g91d3de7240b8 #1
[    3.457416] Hardware name: QEMU QEMU Virtual Machine, BIOS
[    3.457633] epc : smp_call_function_many_cond+0x452/0x520
[    3.457736]  ra : on_each_cpu_cond_mask+0x1e/0x30
[    3.457786] epc : ffffffff800b669a ra : ffffffff800b67c2 sp : ff2000000000bb50
[    3.457824]  gp : ffffffff815212b8 tp : ff6000008014f080 t0 : 000000000000003f
[    3.457859]  t1 : ffffffff815221e0 t2 : 000000000000000f s0 : ff2000000000bc10
[    3.457920]  s1 : 0000000000000040 a0 : ffffffff815221e0 a1 : 0000000000000001
[    3.457953]  a2 : 0000000000010000 a3 : 0000000000000003 a4 : 0000000000000000
[    3.458006]  a5 : 0000000000000000 a6 : ffffffffffffffff a7 : 0000000000000000
[    3.458042]  s2 : ffffffff815223be s3 : 00fffffffffff000 s4 : ff600001ffe38fc0
[    3.458076]  s5 : ff600001ff950d00 s6 : 0000000200000120 s7 : 0000000000000001
[    3.458109]  s8 : 0000000000000001 s9 : ff60000080841ef0 s10: 0000000000000001
[    3.458141]  s11: ffffffff81524812 t3 : 0000000000000001 t4 : ff60000080092bc0
[    3.458172]  t5 : 0000000000000000 t6 : ff200000000236d0
[    3.458203] status: 0000000200000100 badaddr: ffffffff800b669a cause: 0000000000000003
[    3.458373] [<ffffffff800b669a>] smp_call_function_many_cond+0x452/0x520
[    3.458593] [<ffffffff800b67c2>] on_each_cpu_cond_mask+0x1e/0x30
[    3.458625] [<ffffffff8000e4ca>] __flush_tlb_range+0x118/0x1ca
[    3.458656] [<ffffffff8000e6b2>] flush_tlb_kernel_range+0x1e/0x26
[    3.458683] [<ffffffff801ea56a>] kfence_protect+0xc0/0xce
[    3.458717] [<ffffffff801e9456>] kfence_guarded_free+0xc6/0x1c0
[    3.458742] [<ffffffff801e9d6c>] __kfence_free+0x62/0xc6
[    3.458764] [<ffffffff801c57d8>] kfree+0x106/0x32c
[    3.458786] [<ffffffff80588cf2>] detach_buf_split+0x188/0x1a8
[    3.458816] [<ffffffff8058708c>] virtqueue_get_buf_ctx+0xb6/0x1f6
[    3.458839] [<ffffffff805871da>] virtqueue_get_buf+0xe/0x16
[    3.458880] [<ffffffff80613d6a>] virtblk_done+0x5c/0xe2
[    3.458908] [<ffffffff8058766e>] vring_interrupt+0x6a/0x74
[    3.458930] [<ffffffff800747d8>] __handle_irq_event_percpu+0x7c/0xe2
[    3.458956] [<ffffffff800748f0>] handle_irq_event+0x3c/0x86
[    3.458978] [<ffffffff800786cc>] handle_simple_irq+0x9e/0xbe
[    3.459004] [<ffffffff80073934>] generic_handle_domain_irq+0x1c/0x2a
[    3.459027] [<ffffffff804bf87c>] imsic_handle_irq+0xba/0x120
[    3.459056] [<ffffffff80073934>] generic_handle_domain_irq+0x1c/0x2a
[    3.459080] [<ffffffff804bdb76>] riscv_intc_aia_irq+0x24/0x34
[    3.459103] [<ffffffff809d0452>] handle_riscv_irq+0x2e/0x4c
[    3.459133] [<ffffffff809d923e>] call_on_irq_stack+0x32/0x40

So only flush the local TLB and let the lazy kfence page fault handling
deal with the faults which could happen when a core has an old protected
pte version cached in its TLB. That leads to potential inaccuracies which
can be tolerated when using kfence.

Fixes: 47513f2 ("riscv: Enable KFENCE for riscv64")
Signed-off-by: Alexandre Ghiti <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
The vmemmap's, which is used for RV64 with SPARSEMEM_VMEMMAP, page
tables are populated using pmd (page middle directory) hugetables.
However, the pmd allocation is not using the generic mechanism used by
the VMA code (e.g. pmd_alloc()), or the RISC-V specific
create_pgd_mapping()/alloc_pmd_late(). Instead, the vmemmap page table
code allocates a page, and calls vmemmap_set_pmd(). This results in
that the pmd ctor is *not* called, nor would it make sense to do so.

Now, when tearing down a vmemmap page table pmd, the cleanup code
would unconditionally, and incorrectly call the pmd dtor, which
results in a crash (best case).

This issue was found when running the HMM selftests:

  | tools/testing/selftests/mm# ./test_hmm.sh smoke
  | ... # when unloading the test_hmm.ko module
  | page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10915b
  | flags: 0x1000000000000000(node=0|zone=1)
  | raw: 1000000000000000 0000000000000000 dead000000000122 0000000000000000
  | raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
  | page dumped because: VM_BUG_ON_PAGE(ptdesc->pmd_huge_pte)
  | ------------[ cut here ]------------
  | kernel BUG at include/linux/mm.h:3080!
  | Kernel BUG [#1]
  | Modules linked in: test_hmm(-) sch_fq_codel fuse drm drm_panel_orientation_quirks backlight dm_mod
  | CPU: 1 UID: 0 PID: 514 Comm: modprobe Tainted: G        W          6.12.0-00982-gf2a4f1682d07 #2
  | Tainted: [W]=WARN
  | Hardware name: riscv-virtio qemu/qemu, BIOS 2024.10 10/01/2024
  | epc : remove_pgd_mapping+0xbec/0x1070
  |  ra : remove_pgd_mapping+0xbec/0x1070
  | epc : ffffffff80010a68 ra : ffffffff80010a68 sp : ff20000000a73940
  |  gp : ffffffff827b2d88 tp : ff6000008785da40 t0 : ffffffff80fbce04
  |  t1 : 0720072007200720 t2 : 706d756420656761 s0 : ff20000000a73a50
  |  s1 : ff6000008915cff8 a0 : 0000000000000039 a1 : 0000000000000008
  |  a2 : ff600003fff0de20 a3 : 0000000000000000 a4 : 0000000000000000
  |  a5 : 0000000000000000 a6 : c0000000ffffefff a7 : ffffffff824469b8
  |  s2 : ff1c0000022456c0 s3 : ff1ffffffdbfffff s4 : ff6000008915c000
  |  s5 : ff6000008915c000 s6 : ff6000008915c000 s7 : ff1ffffffdc00000
  |  s8 : 0000000000000001 s9 : ff1ffffffdc00000 s10: ffffffff819a31f0
  |  s11: ffffffffffffffff t3 : ffffffff8000c950 t4 : ff60000080244f00
  |  t5 : ff60000080244000 t6 : ff20000000a73708
  | status: 0000000200000120 badaddr: ffffffff80010a68 cause: 0000000000000003
  | [<ffffffff80010a68>] remove_pgd_mapping+0xbec/0x1070
  | [<ffffffff80fd238e>] vmemmap_free+0x14/0x1e
  | [<ffffffff8032e698>] section_deactivate+0x220/0x452
  | [<ffffffff8032ef7e>] sparse_remove_section+0x4a/0x58
  | [<ffffffff802f8700>] __remove_pages+0x7e/0xba
  | [<ffffffff803760d8>] memunmap_pages+0x2bc/0x3fe
  | [<ffffffff02a3ca28>] dmirror_device_remove_chunks+0x2ea/0x518 [test_hmm]
  | [<ffffffff02a3e026>] hmm_dmirror_exit+0x3e/0x1018 [test_hmm]
  | [<ffffffff80102c14>] __riscv_sys_delete_module+0x15a/0x2a6
  | [<ffffffff80fd020c>] do_trap_ecall_u+0x1f2/0x266
  | [<ffffffff80fde0a2>] _new_vmalloc_restore_context_a0+0xc6/0xd2
  | Code: bf51 7597 0184 8593 76a5 854a 4097 0029 80e7 2c00 (9002) 7597
  | ---[ end trace 0000000000000000 ]---
  | Kernel panic - not syncing: Fatal exception in interrupt

Add a check to avoid calling the pmd dtor, if the calling context is
vmemmap_free().

Fixes: c75a74f ("riscv: mm: Add memory hotplugging support")
Signed-off-by: Björn Töpel <[email protected]>
Reviewed-by: Alexandre Ghiti <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Cc: [email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
This reworks hci_cb_list to not use mutex hci_cb_list_lock to avoid bugs
like the bellow:

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:585
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 5070, name: kworker/u9:2
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
4 locks held by kworker/u9:2/5070:
 #0: ffff888015be3948 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline]
 #0: ffff888015be3948 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x1770 kernel/workqueue.c:3335
 #1: ffffc90003b6fd00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline]
 #1: ffffc90003b6fd00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x1770 kernel/workqueue.c:3335
 #2: ffff8880665d0078 (&hdev->lock){+.+.}-{3:3}, at: hci_le_create_big_complete_evt+0xcf/0xae0 net/bluetooth/hci_event.c:6914
 #3: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
 #3: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
 #3: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: hci_le_create_big_complete_evt+0xdb/0xae0 net/bluetooth/hci_event.c:6915
CPU: 0 PID: 5070 Comm: kworker/u9:2 Not tainted 6.8.0-syzkaller-08073-g480e035fc4c7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: hci0 hci_rx_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 __might_resched+0x5d4/0x780 kernel/sched/core.c:10187
 __mutex_lock_common kernel/locking/mutex.c:585 [inline]
 __mutex_lock+0xc1/0xd70 kernel/locking/mutex.c:752
 hci_connect_cfm include/net/bluetooth/hci_core.h:2004 [inline]
 hci_le_create_big_complete_evt+0x3d9/0xae0 net/bluetooth/hci_event.c:6939
 hci_event_func net/bluetooth/hci_event.c:7514 [inline]
 hci_event_packet+0xa53/0x1540 net/bluetooth/hci_event.c:7569
 hci_rx_work+0x3e8/0xca0 net/bluetooth/hci_core.c:4171
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>

Reported-by: [email protected]
Tested-by: [email protected]
Closes: https://syzkaller.appspot.com/bug?extid=2fb0835e0c9cefc34614
Signed-off-by: Luiz Augusto von Dentz <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
This fixes the circular locking dependency warning below, by
releasing the socket lock before enterning iso_listen_bis, to
avoid any potential deadlock with hdev lock.

[   75.307983] ======================================================
[   75.307984] WARNING: possible circular locking dependency detected
[   75.307985] 6.12.0-rc6+ torvalds#22 Not tainted
[   75.307987] ------------------------------------------------------
[   75.307987] kworker/u81:2/2623 is trying to acquire lock:
[   75.307988] ffff8fde1769da58 (sk_lock-AF_BLUETOOTH-BTPROTO_ISO)
               at: iso_connect_cfm+0x253/0x840 [bluetooth]
[   75.308021]
               but task is already holding lock:
[   75.308022] ffff8fdd61a10078 (&hdev->lock)
               at: hci_le_per_adv_report_evt+0x47/0x2f0 [bluetooth]
[   75.308053]
               which lock already depends on the new lock.

[   75.308054]
               the existing dependency chain (in reverse order) is:
[   75.308055]
               -> #1 (&hdev->lock){+.+.}-{3:3}:
[   75.308057]        __mutex_lock+0xad/0xc50
[   75.308061]        mutex_lock_nested+0x1b/0x30
[   75.308063]        iso_sock_listen+0x143/0x5c0 [bluetooth]
[   75.308085]        __sys_listen_socket+0x49/0x60
[   75.308088]        __x64_sys_listen+0x4c/0x90
[   75.308090]        x64_sys_call+0x2517/0x25f0
[   75.308092]        do_syscall_64+0x87/0x150
[   75.308095]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[   75.308098]
               -> #0 (sk_lock-AF_BLUETOOTH-BTPROTO_ISO){+.+.}-{0:0}:
[   75.308100]        __lock_acquire+0x155e/0x25f0
[   75.308103]        lock_acquire+0xc9/0x300
[   75.308105]        lock_sock_nested+0x32/0x90
[   75.308107]        iso_connect_cfm+0x253/0x840 [bluetooth]
[   75.308128]        hci_connect_cfm+0x6c/0x190 [bluetooth]
[   75.308155]        hci_le_per_adv_report_evt+0x27b/0x2f0 [bluetooth]
[   75.308180]        hci_le_meta_evt+0xe7/0x200 [bluetooth]
[   75.308206]        hci_event_packet+0x21f/0x5c0 [bluetooth]
[   75.308230]        hci_rx_work+0x3ae/0xb10 [bluetooth]
[   75.308254]        process_one_work+0x212/0x740
[   75.308256]        worker_thread+0x1bd/0x3a0
[   75.308258]        kthread+0xe4/0x120
[   75.308259]        ret_from_fork+0x44/0x70
[   75.308261]        ret_from_fork_asm+0x1a/0x30
[   75.308263]
               other info that might help us debug this:

[   75.308264]  Possible unsafe locking scenario:

[   75.308264]        CPU0                CPU1
[   75.308265]        ----                ----
[   75.308265]   lock(&hdev->lock);
[   75.308267]                            lock(sk_lock-
                                                AF_BLUETOOTH-BTPROTO_ISO);
[   75.308268]                            lock(&hdev->lock);
[   75.308269]   lock(sk_lock-AF_BLUETOOTH-BTPROTO_ISO);
[   75.308270]
                *** DEADLOCK ***

[   75.308271] 4 locks held by kworker/u81:2/2623:
[   75.308272]  #0: ffff8fdd66e52148 ((wq_completion)hci0#2){+.+.}-{0:0},
                at: process_one_work+0x443/0x740
[   75.308276]  #1: ffffafb488b7fe48 ((work_completion)(&hdev->rx_work)),
                at: process_one_work+0x1ce/0x740
[   75.308280]  #2: ffff8fdd61a10078 (&hdev->lock){+.+.}-{3:3}
                at: hci_le_per_adv_report_evt+0x47/0x2f0 [bluetooth]
[   75.308304]  #3: ffffffffb6ba4900 (rcu_read_lock){....}-{1:2},
                at: hci_connect_cfm+0x29/0x190 [bluetooth]

Fixes: 02171da ("Bluetooth: ISO: Add hcon for listening bis sk")
Signed-off-by: Iulia Tanasescu <[email protected]>
Signed-off-by: Luiz Augusto von Dentz <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
This fixes the circular locking dependency warning below, by reworking
iso_sock_recvmsg, to ensure that the socket lock is always released
before calling a function that locks hdev.

[  561.670344] ======================================================
[  561.670346] WARNING: possible circular locking dependency detected
[  561.670349] 6.12.0-rc6+ torvalds#26 Not tainted
[  561.670351] ------------------------------------------------------
[  561.670353] iso-tester/3289 is trying to acquire lock:
[  561.670355] ffff88811f600078 (&hdev->lock){+.+.}-{3:3},
               at: iso_conn_big_sync+0x73/0x260 [bluetooth]
[  561.670405]
               but task is already holding lock:
[  561.670407] ffff88815af58258 (sk_lock-AF_BLUETOOTH){+.+.}-{0:0},
               at: iso_sock_recvmsg+0xbf/0x500 [bluetooth]
[  561.670450]
               which lock already depends on the new lock.

[  561.670452]
               the existing dependency chain (in reverse order) is:
[  561.670453]
               -> #2 (sk_lock-AF_BLUETOOTH){+.+.}-{0:0}:
[  561.670458]        lock_acquire+0x7c/0xc0
[  561.670463]        lock_sock_nested+0x3b/0xf0
[  561.670467]        bt_accept_dequeue+0x1a5/0x4d0 [bluetooth]
[  561.670510]        iso_sock_accept+0x271/0x830 [bluetooth]
[  561.670547]        do_accept+0x3dd/0x610
[  561.670550]        __sys_accept4+0xd8/0x170
[  561.670553]        __x64_sys_accept+0x74/0xc0
[  561.670556]        x64_sys_call+0x17d6/0x25f0
[  561.670559]        do_syscall_64+0x87/0x150
[  561.670563]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  561.670567]
               -> #1 (sk_lock-AF_BLUETOOTH-BTPROTO_ISO){+.+.}-{0:0}:
[  561.670571]        lock_acquire+0x7c/0xc0
[  561.670574]        lock_sock_nested+0x3b/0xf0
[  561.670577]        iso_sock_listen+0x2de/0xf30 [bluetooth]
[  561.670617]        __sys_listen_socket+0xef/0x130
[  561.670620]        __x64_sys_listen+0xe1/0x190
[  561.670623]        x64_sys_call+0x2517/0x25f0
[  561.670626]        do_syscall_64+0x87/0x150
[  561.670629]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  561.670632]
               -> #0 (&hdev->lock){+.+.}-{3:3}:
[  561.670636]        __lock_acquire+0x32ad/0x6ab0
[  561.670639]        lock_acquire.part.0+0x118/0x360
[  561.670642]        lock_acquire+0x7c/0xc0
[  561.670644]        __mutex_lock+0x18d/0x12f0
[  561.670647]        mutex_lock_nested+0x1b/0x30
[  561.670651]        iso_conn_big_sync+0x73/0x260 [bluetooth]
[  561.670687]        iso_sock_recvmsg+0x3e9/0x500 [bluetooth]
[  561.670722]        sock_recvmsg+0x1d5/0x240
[  561.670725]        sock_read_iter+0x27d/0x470
[  561.670727]        vfs_read+0x9a0/0xd30
[  561.670731]        ksys_read+0x1a8/0x250
[  561.670733]        __x64_sys_read+0x72/0xc0
[  561.670736]        x64_sys_call+0x1b12/0x25f0
[  561.670738]        do_syscall_64+0x87/0x150
[  561.670741]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  561.670744]
               other info that might help us debug this:

[  561.670745] Chain exists of:
&hdev->lock --> sk_lock-AF_BLUETOOTH-BTPROTO_ISO --> sk_lock-AF_BLUETOOTH

[  561.670751]  Possible unsafe locking scenario:

[  561.670753]        CPU0                    CPU1
[  561.670754]        ----                    ----
[  561.670756]   lock(sk_lock-AF_BLUETOOTH);
[  561.670758]                                lock(sk_lock
                                              AF_BLUETOOTH-BTPROTO_ISO);
[  561.670761]                                lock(sk_lock-AF_BLUETOOTH);
[  561.670764]   lock(&hdev->lock);
[  561.670767]
                *** DEADLOCK ***

Fixes: 07a9342 ("Bluetooth: ISO: Send BIG Create Sync via hci_sync")
Signed-off-by: Iulia Tanasescu <[email protected]>
Signed-off-by: Luiz Augusto von Dentz <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
hci_devcd_append may lead to the release of the skb, so it cannot be
accessed once it is called.

==================================================================
BUG: KASAN: slab-use-after-free in btmtk_process_coredump+0x2a7/0x2d0 [btmtk]
Read of size 4 at addr ffff888033cfabb0 by task kworker/0:3/82

CPU: 0 PID: 82 Comm: kworker/0:3 Tainted: G     U             6.6.40-lockdep-03464-g1d8b4eb3060e #1 b0b3c1cc0c842735643fb411799d97921d1f688c
Hardware name: Google Yaviks_Ufs/Yaviks_Ufs, BIOS Google_Yaviks_Ufs.15217.552.0 05/07/2024
Workqueue: events btusb_rx_work [btusb]
Call Trace:
 <TASK>
 dump_stack_lvl+0xfd/0x150
 print_report+0x131/0x780
 kasan_report+0x177/0x1c0
 btmtk_process_coredump+0x2a7/0x2d0 [btmtk 03edd567dd71a65958807c95a65db31d433e1d01]
 btusb_recv_acl_mtk+0x11c/0x1a0 [btusb 675430d1e87c4f24d0c1f80efe600757a0f32bec]
 btusb_rx_work+0x9e/0xe0 [btusb 675430d1e87c4f24d0c1f80efe600757a0f32bec]
 worker_thread+0xe44/0x2cc0
 kthread+0x2ff/0x3a0
 ret_from_fork+0x51/0x80
 ret_from_fork_asm+0x1b/0x30
 </TASK>

Allocated by task 82:
 stack_trace_save+0xdc/0x190
 kasan_set_track+0x4e/0x80
 __kasan_slab_alloc+0x4e/0x60
 kmem_cache_alloc+0x19f/0x360
 skb_clone+0x132/0xf70
 btusb_recv_acl_mtk+0x104/0x1a0 [btusb]
 btusb_rx_work+0x9e/0xe0 [btusb]
 worker_thread+0xe44/0x2cc0
 kthread+0x2ff/0x3a0
 ret_from_fork+0x51/0x80
 ret_from_fork_asm+0x1b/0x30

Freed by task 1733:
 stack_trace_save+0xdc/0x190
 kasan_set_track+0x4e/0x80
 kasan_save_free_info+0x28/0xb0
 ____kasan_slab_free+0xfd/0x170
 kmem_cache_free+0x183/0x3f0
 hci_devcd_rx+0x91a/0x2060 [bluetooth]
 worker_thread+0xe44/0x2cc0
 kthread+0x2ff/0x3a0
 ret_from_fork+0x51/0x80
 ret_from_fork_asm+0x1b/0x30

The buggy address belongs to the object at ffff888033cfab40
 which belongs to the cache skbuff_head_cache of size 232
The buggy address is located 112 bytes inside of
 freed 232-byte region [ffff888033cfab40, ffff888033cfac28)

The buggy address belongs to the physical page:
page:00000000a174ba93 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x33cfa
head:00000000a174ba93 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0x4000000000000840(slab|head|zone=1)
page_type: 0xffffffff()
raw: 4000000000000840 ffff888100848a00 0000000000000000 0000000000000001
raw: 0000000000000000 0000000080190019 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888033cfaa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
 ffff888033cfab00: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
>ffff888033cfab80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888033cfac00: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
 ffff888033cfac80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Check if we need to call hci_devcd_complete before calling
hci_devcd_append. That requires that we check data->cd_info.cnt >=
MTK_COREDUMP_NUM instead of data->cd_info.cnt > MTK_COREDUMP_NUM, as we
increment data->cd_info.cnt only once the call to hci_devcd_append
succeeds.

Fixes: 0b70151 ("Bluetooth: btusb: mediatek: add MediaTek devcoredump support")
Signed-off-by: Thadeu Lima de Souza Cascardo <[email protected]>
Signed-off-by: Luiz Augusto von Dentz <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
The current implementation removes cache tags after disabling ATS,
leading to potential memory leaks and kernel crashes. Specifically,
CACHE_TAG_DEVTLB type cache tags may still remain in the list even
after the domain is freed, causing a use-after-free condition.

This issue really shows up when multiple VFs from different PFs
passed through to a single user-space process via vfio-pci. In such
cases, the kernel may crash with kernel messages like:

 BUG: kernel NULL pointer dereference, address: 0000000000000014
 PGD 19036a067 P4D 1940a3067 PUD 136c9b067 PMD 0
 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
 CPU: 74 UID: 0 PID: 3183 Comm: testCli Not tainted 6.11.9 #2
 RIP: 0010:cache_tag_flush_range+0x9b/0x250
 Call Trace:
  <TASK>
  ? __die+0x1f/0x60
  ? page_fault_oops+0x163/0x590
  ? exc_page_fault+0x72/0x190
  ? asm_exc_page_fault+0x22/0x30
  ? cache_tag_flush_range+0x9b/0x250
  ? cache_tag_flush_range+0x5d/0x250
  intel_iommu_tlb_sync+0x29/0x40
  intel_iommu_unmap_pages+0xfe/0x160
  __iommu_unmap+0xd8/0x1a0
  vfio_unmap_unpin+0x182/0x340 [vfio_iommu_type1]
  vfio_remove_dma+0x2a/0xb0 [vfio_iommu_type1]
  vfio_iommu_type1_ioctl+0xafa/0x18e0 [vfio_iommu_type1]

Move cache_tag_unassign_domain() before iommu_disable_pci_caps() to fix
it.

Fixes: 3b1d9e2 ("iommu/vt-d: Add cache tag assignment interface")
Cc: [email protected]
Signed-off-by: Lu Baolu <[email protected]>
Reviewed-by: Kevin Tian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Joerg Roedel <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
The qi_batch is allocated when assigning cache tag for a domain. While
for nested parent domain, it is missed. Hence, when trying to map pages
to the nested parent, NULL dereference occurred. Also, there is potential
memleak since there is no lock around domain->qi_batch allocation.

To solve it, add a helper for qi_batch allocation, and call it in both
the __cache_tag_assign_domain() and __cache_tag_assign_parent_domain().

  BUG: kernel NULL pointer dereference, address: 0000000000000200
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 8104795067 P4D 0
  Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 223 UID: 0 PID: 4357 Comm: qemu-system-x86 Not tainted 6.13.0-rc1-00028-g4b50c3c3b998-dirty #2632
  Call Trace:
   ? __die+0x24/0x70
   ? page_fault_oops+0x80/0x150
   ? do_user_addr_fault+0x63/0x7b0
   ? exc_page_fault+0x7c/0x220
   ? asm_exc_page_fault+0x26/0x30
   ? cache_tag_flush_range_np+0x13c/0x260
   intel_iommu_iotlb_sync_map+0x1a/0x30
   iommu_map+0x61/0xf0
   batch_to_domain+0x188/0x250
   iopt_area_fill_domains+0x125/0x320
   ? rcu_is_watching+0x11/0x50
   iopt_map_pages+0x63/0x100
   iopt_map_common.isra.0+0xa7/0x190
   iopt_map_user_pages+0x6a/0x80
   iommufd_ioas_map+0xcd/0x1d0
   iommufd_fops_ioctl+0x118/0x1c0
   __x64_sys_ioctl+0x93/0xc0
   do_syscall_64+0x71/0x140
   entry_SYSCALL_64_after_hwframe+0x76/0x7e

Fixes: 705c1cd ("iommu/vt-d: Introduce batched cache invalidation")
Cc: [email protected]
Co-developed-by: Lu Baolu <[email protected]>
Signed-off-by: Lu Baolu <[email protected]>
Signed-off-by: Yi Liu <[email protected]>
Reviewed-by: Kevin Tian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Joerg Roedel <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
…s_lock

For storing a value to a queue attribute, the queue_attr_store function
first freezes the queue (->q_usage_counter(io)) and then acquire
->sysfs_lock. This seems not correct as the usual ordering should be to
acquire ->sysfs_lock before freezing the queue. This incorrect ordering
causes the following lockdep splat which we are able to reproduce always
simply by accessing /sys/kernel/debug file using ls command:

[   57.597146] WARNING: possible circular locking dependency detected
[   57.597154] 6.12.0-10553-gb86545e02e8c torvalds#20 Tainted: G        W
[   57.597162] ------------------------------------------------------
[   57.597168] ls/4605 is trying to acquire lock:
[   57.597176] c00000003eb56710 (&mm->mmap_lock){++++}-{4:4}, at: __might_fault+0x58/0xc0
[   57.597200]
               but task is already holding lock:
[   57.597207] c0000018e27c6810 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: iterate_dir+0x94/0x1d4
[   57.597226]
               which lock already depends on the new lock.

[   57.597233]
               the existing dependency chain (in reverse order) is:
[   57.597241]
               -> #5 (&sb->s_type->i_mutex_key#3){++++}-{4:4}:
[   57.597255]        down_write+0x6c/0x18c
[   57.597264]        start_creating+0xb4/0x24c
[   57.597274]        debugfs_create_dir+0x2c/0x1e8
[   57.597283]        blk_register_queue+0xec/0x294
[   57.597292]        add_disk_fwnode+0x2e4/0x548
[   57.597302]        brd_alloc+0x2c8/0x338
[   57.597309]        brd_init+0x100/0x178
[   57.597317]        do_one_initcall+0x88/0x3e4
[   57.597326]        kernel_init_freeable+0x3cc/0x6e0
[   57.597334]        kernel_init+0x34/0x1cc
[   57.597342]        ret_from_kernel_user_thread+0x14/0x1c
[   57.597350]
               -> #4 (&q->debugfs_mutex){+.+.}-{4:4}:
[   57.597362]        __mutex_lock+0xfc/0x12a0
[   57.597370]        blk_register_queue+0xd4/0x294
[   57.597379]        add_disk_fwnode+0x2e4/0x548
[   57.597388]        brd_alloc+0x2c8/0x338
[   57.597395]        brd_init+0x100/0x178
[   57.597402]        do_one_initcall+0x88/0x3e4
[   57.597410]        kernel_init_freeable+0x3cc/0x6e0
[   57.597418]        kernel_init+0x34/0x1cc
[   57.597426]        ret_from_kernel_user_thread+0x14/0x1c
[   57.597434]
               -> #3 (&q->sysfs_lock){+.+.}-{4:4}:
[   57.597446]        __mutex_lock+0xfc/0x12a0
[   57.597454]        queue_attr_store+0x9c/0x110
[   57.597462]        sysfs_kf_write+0x70/0xb0
[   57.597471]        kernfs_fop_write_iter+0x1b0/0x2ac
[   57.597480]        vfs_write+0x3dc/0x6e8
[   57.597488]        ksys_write+0x84/0x140
[   57.597495]        system_call_exception+0x130/0x360
[   57.597504]        system_call_common+0x160/0x2c4
[   57.597516]
               -> #2 (&q->q_usage_counter(io)torvalds#21){++++}-{0:0}:
[   57.597530]        __submit_bio+0x5ec/0x828
[   57.597538]        submit_bio_noacct_nocheck+0x1e4/0x4f0
[   57.597547]        iomap_readahead+0x2a0/0x448
[   57.597556]        xfs_vm_readahead+0x28/0x3c
[   57.597564]        read_pages+0x88/0x41c
[   57.597571]        page_cache_ra_unbounded+0x1ac/0x2d8
[   57.597580]        filemap_get_pages+0x188/0x984
[   57.597588]        filemap_read+0x13c/0x4bc
[   57.597596]        xfs_file_buffered_read+0x88/0x17c
[   57.597605]        xfs_file_read_iter+0xac/0x158
[   57.597614]        vfs_read+0x2d4/0x3b4
[   57.597622]        ksys_read+0x84/0x144
[   57.597629]        system_call_exception+0x130/0x360
[   57.597637]        system_call_common+0x160/0x2c4
[   57.597647]
               -> #1 (mapping.invalidate_lock#2){++++}-{4:4}:
[   57.597661]        down_read+0x6c/0x220
[   57.597669]        filemap_fault+0x870/0x100c
[   57.597677]        xfs_filemap_fault+0xc4/0x18c
[   57.597684]        __do_fault+0x64/0x164
[   57.597693]        __handle_mm_fault+0x1274/0x1dac
[   57.597702]        handle_mm_fault+0x248/0x484
[   57.597711]        ___do_page_fault+0x428/0xc0c
[   57.597719]        hash__do_page_fault+0x30/0x68
[   57.597727]        do_hash_fault+0x90/0x35c
[   57.597736]        data_access_common_virt+0x210/0x220
[   57.597745]        _copy_from_user+0xf8/0x19c
[   57.597754]        sel_write_load+0x178/0xd54
[   57.597762]        vfs_write+0x108/0x6e8
[   57.597769]        ksys_write+0x84/0x140
[   57.597777]        system_call_exception+0x130/0x360
[   57.597785]        system_call_common+0x160/0x2c4
[   57.597794]
               -> #0 (&mm->mmap_lock){++++}-{4:4}:
[   57.597806]        __lock_acquire+0x17cc/0x2330
[   57.597814]        lock_acquire+0x138/0x400
[   57.597822]        __might_fault+0x7c/0xc0
[   57.597830]        filldir64+0xe8/0x390
[   57.597839]        dcache_readdir+0x80/0x2d4
[   57.597846]        iterate_dir+0xd8/0x1d4
[   57.597855]        sys_getdents64+0x88/0x2d4
[   57.597864]        system_call_exception+0x130/0x360
[   57.597872]        system_call_common+0x160/0x2c4
[   57.597881]
               other info that might help us debug this:

[   57.597888] Chain exists of:
                 &mm->mmap_lock --> &q->debugfs_mutex --> &sb->s_type->i_mutex_key#3

[   57.597905]  Possible unsafe locking scenario:

[   57.597911]        CPU0                    CPU1
[   57.597917]        ----                    ----
[   57.597922]   rlock(&sb->s_type->i_mutex_key#3);
[   57.597932]                                lock(&q->debugfs_mutex);
[   57.597940]                                lock(&sb->s_type->i_mutex_key#3);
[   57.597950]   rlock(&mm->mmap_lock);
[   57.597958]
                *** DEADLOCK ***

[   57.597965] 2 locks held by ls/4605:
[   57.597971]  #0: c0000000137c12f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0xcc/0x154
[   57.597989]  #1: c0000018e27c6810 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: iterate_dir+0x94/0x1d4

Prevent the above lockdep warning by acquiring ->sysfs_lock before
freezing the queue while storing a queue attribute in queue_attr_store
function. Later, we also found[1] another function __blk_mq_update_nr_
hw_queues where we first freeze queue and then acquire the ->sysfs_lock.
So we've also updated lock ordering in __blk_mq_update_nr_hw_queues
function and ensured that in all code paths we follow the correct lock
ordering i.e. acquire ->sysfs_lock before freezing the queue.

[1] https://lore.kernel.org/all/CAFj5m9Ke8+EHKQBs_Nk6hqd=LGXtk4mUxZUN5==ZcCjnZSBwHw@mail.gmail.com/

Reported-by: [email protected]
Fixes: af28141 ("block: freeze the queue in queue_attr_store")
Tested-by: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Nilay Shroff <[email protected]>
Reviewed-by: Ming Lei <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
 into HEAD

KVM/riscv fixes for 6.13, take #1

- Replace csr_write() with csr_set() for HVIEN PMU overflow bit
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
syzbot reported the following crash [1]

Issue came with the blamed commit. Instead of going through
all the iov components, we keep using the first one
and end up with a malformed skb.

[1]

kernel BUG at net/core/skbuff.c:2849 !
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 6230 Comm: syz-executor132 Not tainted 6.13.0-rc1-syzkaller-00407-g96b6fcc0ee41 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
 RIP: 0010:__pskb_pull_tail+0x1568/0x1570 net/core/skbuff.c:2848
Code: 38 c1 0f 8c 32 f1 ff ff 4c 89 f7 e8 92 96 74 f8 e9 25 f1 ff ff e8 e8 ae 09 f8 48 8b 5c 24 08 e9 eb fb ff ff e8 d9 ae 09 f8 90 <0f> 0b 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90004cbef30 EFLAGS: 00010293
RAX: ffffffff8995c347 RBX: 00000000fffffff2 RCX: ffff88802cf45a00
RDX: 0000000000000000 RSI: 00000000fffffff2 RDI: 0000000000000000
RBP: ffff88807df0c06a R08: ffffffff8995b084 R09: 1ffff1100fbe185c
R10: dffffc0000000000 R11: ffffed100fbe185d R12: ffff888076e85d50
R13: ffff888076e85c80 R14: ffff888076e85cf4 R15: ffff888076e85c80
FS:  00007f0dca6ea6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0dca6ead58 CR3: 00000000119da000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
  skb_cow_data+0x2da/0xcb0 net/core/skbuff.c:5284
  tipc_aead_decrypt net/tipc/crypto.c:894 [inline]
  tipc_crypto_rcv+0x402/0x24e0 net/tipc/crypto.c:1844
  tipc_rcv+0x57e/0x12a0 net/tipc/node.c:2109
  tipc_l2_rcv_msg+0x2bd/0x450 net/tipc/bearer.c:668
  __netif_receive_skb_list_ptype net/core/dev.c:5720 [inline]
  __netif_receive_skb_list_core+0x8b7/0x980 net/core/dev.c:5762
  __netif_receive_skb_list net/core/dev.c:5814 [inline]
  netif_receive_skb_list_internal+0xa51/0xe30 net/core/dev.c:5905
  gro_normal_list include/net/gro.h:515 [inline]
  napi_complete_done+0x2b5/0x870 net/core/dev.c:6256
  napi_complete include/linux/netdevice.h:567 [inline]
  tun_get_user+0x2ea0/0x4890 drivers/net/tun.c:1982
  tun_chr_write_iter+0x10d/0x1f0 drivers/net/tun.c:2057
 do_iter_readv_writev+0x600/0x880
  vfs_writev+0x376/0xba0 fs/read_write.c:1050
  do_writev+0x1b6/0x360 fs/read_write.c:1096
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: de4f5fe ("iov_iter: add iter_iovec() helper")
Reported-by: [email protected]
Closes: https://lore.kernel.org/netdev/[email protected]/T/#u
Cc: [email protected]
Signed-off-by: Eric Dumazet <[email protected]>
Reviewed-by: Joe Damato <[email protected]>
Reviewed-by: Jens Axboe <[email protected]>
Acked-by: Willem de Bruijn <[email protected]>
Acked-by: Michael S. Tsirkin <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
link down work may be scheduled before lgr freed but execute
after lgr freed, which may result in crash. So it is need to
hold a reference before shedule link down work, and put the
reference after work executed or canceled.

The relevant crash call stack as follows:
 list_del corruption. prev->next should be ffffb638c9c0fe20,
    but was 0000000000000000
 ------------[ cut here ]------------
 kernel BUG at lib/list_debug.c:51!
 invalid opcode: 0000 [#1] SMP NOPTI
 CPU: 6 PID: 978112 Comm: kworker/6:119 Kdump: loaded Tainted: G #1
 Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 2221b89 04/01/2014
 Workqueue: events smc_link_down_work [smc]
 RIP: 0010:__list_del_entry_valid.cold+0x31/0x47
 RSP: 0018:ffffb638c9c0fdd8 EFLAGS: 00010086
 RAX: 0000000000000054 RBX: ffff942fb75e5128 RCX: 0000000000000000
 RDX: ffff943520930aa0 RSI: ffff94352091fc80 RDI: ffff94352091fc80
 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffb638c9c0fc38
 R10: ffffb638c9c0fc30 R11: ffffffffa015eb28 R12: 0000000000000002
 R13: ffffb638c9c0fe20 R14: 0000000000000001 R15: ffff942f9cd051c0
 FS:  0000000000000000(0000) GS:ffff943520900000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f4f25214000 CR3: 000000025fbae004 CR4: 00000000007706e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 PKRU: 55555554
 Call Trace:
  rwsem_down_write_slowpath+0x17e/0x470
  smc_link_down_work+0x3c/0x60 [smc]
  process_one_work+0x1ac/0x350
  worker_thread+0x49/0x2f0
  ? rescuer_thread+0x360/0x360
  kthread+0x118/0x140
  ? __kthread_bind_mask+0x60/0x60
  ret_from_fork+0x1f/0x30

Fixes: 541afa1 ("net/smc: add smcr_port_err() and smcr_link_down() processing")
Signed-off-by: Guangguan Wang <[email protected]>
Reviewed-by: Tony Lu <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 24, 2024
Google Juniper and other Chromebook platforms have a very old bootloader
which populates /firmware node without proper address/size-cells leading
to warnings:

  Missing '#address-cells' in /firmware
  WARNING: CPU: 0 PID: 1 at drivers/of/base.c:106 of_bus_n_addr_cells+0x90/0xf0
  Modules linked in:
  CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0 #1 933ab9971ff4d5dc58cb378a96f64c7f72e3454d
  Hardware name: Google juniper sku16 board (DT)
  ...
  Missing '#size-cells' in /firmware
  WARNING: CPU: 0 PID: 1 at drivers/of/base.c:133 of_bus_n_size_cells+0x90/0xf0
  Modules linked in:
  CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G        W          6.12.0 #1 933ab9971ff4d5dc58cb378a96f64c7f72e3454d
  Tainted: [W]=WARN
  Hardware name: Google juniper sku16 board (DT)

These platform won't receive updated bootloader/firmware, so add an
exclusion for platforms with a "coreboot" compatible node. While this is
wider than necessary, that's the easiest fix and it doesn't doesn't
matter if we miss checking other platforms using coreboot.

We may revisit this later and address with a fixup to the DT itself.

Reported-by: Sasha Levin <[email protected]>
Closes: https://lore.kernel.org/all/Z0NUdoG17EwuCigT@sashalap/
Cc: AngeloGioacchino Del Regno <[email protected]>
Cc: Matthias Brugger <[email protected]>
Cc: Chen-Yu Tsai <[email protected]>
Cc: Krzysztof Kozlowski <[email protected]>
Signed-off-by: Rob Herring (Arm) <[email protected]>
neuschaefer pushed a commit that referenced this issue Dec 31, 2024
When we call btrfs_read_folio() to bring a folio uptodate, we unlock the
folio. The result of that is that a different thread can modify the
mapping (like remove it with invalidate) before we call folio_lock().
This results in an invalid page and we need to try again.

In particular, if we are relocating concurrently with aborting a
transaction, this can result in a crash like the following:

  BUG: kernel NULL pointer dereference, address: 0000000000000000
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP
  CPU: 76 PID: 1411631 Comm: kworker/u322:5
  Workqueue: events_unbound btrfs_reclaim_bgs_work
  RIP: 0010:set_page_extent_mapped+0x20/0xb0
  RSP: 0018:ffffc900516a7be8 EFLAGS: 00010246
  RAX: ffffea009e851d08 RBX: ffffea009e0b1880 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: ffffc900516a7b90 RDI: ffffea009e0b1880
  RBP: 0000000003573000 R08: 0000000000000001 R09: ffff88c07fd2f3f0
  R10: 0000000000000000 R11: 0000194754b575be R12: 0000000003572000
  R13: 0000000003572fff R14: 0000000000100cca R15: 0000000005582fff
  FS:  0000000000000000(0000) GS:ffff88c07fd00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 000000407d00f002 CR4: 00000000007706f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:
  <TASK>
  ? __die+0x78/0xc0
  ? page_fault_oops+0x2a8/0x3a0
  ? __switch_to+0x133/0x530
  ? wq_worker_running+0xa/0x40
  ? exc_page_fault+0x63/0x130
  ? asm_exc_page_fault+0x22/0x30
  ? set_page_extent_mapped+0x20/0xb0
  relocate_file_extent_cluster+0x1a7/0x940
  relocate_data_extent+0xaf/0x120
  relocate_block_group+0x20f/0x480
  btrfs_relocate_block_group+0x152/0x320
  btrfs_relocate_chunk+0x3d/0x120
  btrfs_reclaim_bgs_work+0x2ae/0x4e0
  process_scheduled_works+0x184/0x370
  worker_thread+0xc6/0x3e0
  ? blk_add_timer+0xb0/0xb0
  kthread+0xae/0xe0
  ? flush_tlb_kernel_range+0x90/0x90
  ret_from_fork+0x2f/0x40
  ? flush_tlb_kernel_range+0x90/0x90
  ret_from_fork_asm+0x11/0x20
  </TASK>

This occurs because cleanup_one_transaction() calls
destroy_delalloc_inodes() which calls invalidate_inode_pages2() which
takes the folio_lock before setting mapping to NULL. We fail to check
this, and subsequently call set_extent_mapping(), which assumes that
mapping != NULL (in fact it asserts that in debug mode)

Note that the "fixes" patch here is not the one that introduced the
race (the very first iteration of this code from 2009) but a more recent
change that made this particular crash happen in practice.

Fixes: e7f1326 ("btrfs: set page extent mapped after read_folio in relocate_one_page")
CC: [email protected] # 6.1+
Reviewed-by: Qu Wenruo <[email protected]>
Signed-off-by: Boris Burkov <[email protected]>
Signed-off-by: David Sterba <[email protected]>
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