ci: apply temporary fix from Yonghong

Apply [0] to fix deadlock in bpf-next, while the upstream patch is landing and propagating through net-next. [0] https://patchwork.kernel.org/project/netdevbpf/patch/[email protected]/ Signed-off-by: Andrii Nakryiko <[email protected]>
kernel-patches · Oct 27, 2023 · c02a155 · c02a155
1 parent aaaeb96
commit c02a155
Showing 1 changed file with 99 additions and 0 deletions.
diff --git a/ci/diffs/0001-net-bpf-Use-sockopt_lock_sock-in-ip_sock_set_tos.patch b/ci/diffs/0001-net-bpf-Use-sockopt_lock_sock-in-ip_sock_set_tos.patch
@@ -0,0 +1,99 @@
+From c8268f8e9fa33c32e1f2f86fc7b703408a396c70 Mon Sep 17 00:00:00 2001
+From: Yonghong Song <[email protected]>
+Date: Fri, 27 Oct 2023 11:24:24 -0700
+Subject: [PATCH] net: bpf: Use sockopt_lock_sock() in ip_sock_set_tos()
+
+With latest sync from net-next tree, bpf-next has a bpf selftest failure:
+  [root@arch-fb-vm1 bpf]# ./test_progs -t setget_sockopt
+  ...
+  [   76.194349] ============================================
+  [   76.194682] WARNING: possible recursive locking detected
+  [   76.195039] 6.6.0-rc7-g37884503df08-dirty #67 Tainted: G        W  OE
+  [   76.195518] --------------------------------------------
+  [   76.195852] new_name/154 is trying to acquire lock:
+  [   76.196159] ffff8c3e06ad8d30 (sk_lock-AF_INET){+.+.}-{0:0}, at: ip_sock_set_tos+0x19/0x30
+  [   76.196669]
+  [   76.196669] but task is already holding lock:
+  [   76.197028] ffff8c3e06ad8d30 (sk_lock-AF_INET){+.+.}-{0:0}, at: inet_listen+0x21/0x70
+  [   76.197517]
+  [   76.197517] other info that might help us debug this:
+  [   76.197919]  Possible unsafe locking scenario:
+  [   76.197919]
+  [   76.198287]        CPU0
+  [   76.198444]        ----
+  [   76.198600]   lock(sk_lock-AF_INET);
+  [   76.198831]   lock(sk_lock-AF_INET);
+  [   76.199062]
+  [   76.199062]  *** DEADLOCK ***
+  [   76.199062]
+  [   76.199420]  May be due to missing lock nesting notation
+  [   76.199420]
+  [   76.199879] 2 locks held by new_name/154:
+  [   76.200131]  #0: ffff8c3e06ad8d30 (sk_lock-AF_INET){+.+.}-{0:0}, at: inet_listen+0x21/0x70
+  [   76.200644]  #1: ffffffff90f96a40 (rcu_read_lock){....}-{1:2}, at: __cgroup_bpf_run_filter_sock_ops+0x55/0x290
+  [   76.201268]
+  [   76.201268] stack backtrace:
+  [   76.201538] CPU: 4 PID: 154 Comm: new_name Tainted: G        W  OE      6.6.0-rc7-g37884503df08-dirty #67
+  [   76.202134] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
+  [   76.202699] Call Trace:
+  [   76.202858]  <TASK>
+  [   76.203002]  dump_stack_lvl+0x4b/0x80
+  [   76.203239]  __lock_acquire+0x740/0x1ec0
+  [   76.203503]  lock_acquire+0xc1/0x2a0
+  [   76.203766]  ? ip_sock_set_tos+0x19/0x30
+  [   76.204050]  ? sk_stream_write_space+0x12a/0x230
+  [   76.204389]  ? lock_release+0xbe/0x260
+  [   76.204661]  lock_sock_nested+0x32/0x80
+  [   76.204942]  ? ip_sock_set_tos+0x19/0x30
+  [   76.205208]  ip_sock_set_tos+0x19/0x30
+  [   76.205452]  do_ip_setsockopt+0x4b3/0x1580
+  [   76.205719]  __bpf_setsockopt+0x62/0xa0
+  [   76.205963]  bpf_sock_ops_setsockopt+0x11/0x20
+  [   76.206247]  bpf_prog_630217292049c96e_bpf_test_sockopt_int+0xbc/0x123
+  [   76.206660]  bpf_prog_493685a3bae00bbd_bpf_test_ip_sockopt+0x49/0x4b
+  [   76.207055]  bpf_prog_b0bcd27f269aeea0_skops_sockopt+0x44c/0xec7
+  [   76.207437]  __cgroup_bpf_run_filter_sock_ops+0xda/0x290
+  [   76.207829]  __inet_listen_sk+0x108/0x1b0
+  [   76.208122]  inet_listen+0x48/0x70
+  [   76.208373]  __sys_listen+0x74/0xb0
+  [   76.208630]  __x64_sys_listen+0x16/0x20
+  [   76.208911]  do_syscall_64+0x3f/0x90
+  [   76.209174]  entry_SYSCALL_64_after_hwframe+0x6e/0xd8
+  ...
+
+Both ip_sock_set_tos() and inet_listen() calls lock_sock(sk) which
+caused a dead lock.
+
+To fix the issue, use sockopt_lock_sock() in ip_sock_set_tos()
+instead. sockopt_lock_sock() will avoid lock_sock() if it is in bpf
+context.
+
+Fixes: 878d951c6712 ("inet: lock the socket in ip_sock_set_tos()")
+Suggested-by: Martin KaFai Lau <[email protected]>
+Signed-off-by: Yonghong Song <[email protected]>
+Signed-off-by: Andrii Nakryiko <[email protected]>
+Reviewed-by: Eric Dumazet <[email protected]>
+Link: https://lore.kernel.org/bpf/[email protected]
+---
+ net/ipv4/ip_sockglue.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
+index 9c68b6b74d9f..2efc53526a38 100644
+--- a/net/ipv4/ip_sockglue.c
++++ b/net/ipv4/ip_sockglue.c
+@@ -602,9 +602,9 @@ void __ip_sock_set_tos(struct sock *sk, int val)
+
+ void ip_sock_set_tos(struct sock *sk, int val)
+ {
+-	lock_sock(sk);
++	sockopt_lock_sock(sk);
+ 	__ip_sock_set_tos(sk, val);
+-	release_sock(sk);
++	sockopt_release_sock(sk);
+ }
+ EXPORT_SYMBOL(ip_sock_set_tos);
+
+-- 
+2.34.1
+