If hooking in __DATA_CONST/__AUTH_CONST, promise writable before trying to write

[maniackk]

Issue: #80 and #82.

fix：int mprotect(void *address, size_t size, int protect); function Require address alignment. Before that, I tried
to use vm_protect function, I found some case that vm_protect return KERN_SUCCESS , but memory don't set VM_PROT_WRITE success.

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[maniackk]

oldProtection = get_protection(rebindings); is wrong, It save struct rebindings_entry *rebindings memory protection. We should save section protection.

I commit code that oldProtection = get_protection((void *)trunc_address);.

and I found a problem when program set same section protection in multithread(iOS 14.5).

[zhutc]

This issue appears again in iOS15.

Exception Type:  EXC_BAD_ACCESS (SIGKILL)
Exception Subtype: KERN_PROTECTION_FAILURE at 0x00000001d4424da8
VM Region Info: 0x1d4424da8 is in 0x1d44249b8-0x1d4450278;  bytes after start: 1008  bytes before end: 177359
      REGION TYPE                 START - END      [ VSIZE] PRT/MAX SHRMOD  REGION DETAIL
      __DATA_CONST             1d43fc5c0-1d44249b8 [  161K] r--/rw- SM=COW  ...k/MediaRemote
--->  __DATA_CONST             1d44249b8-1d4450278 [  174K] r--/rw- SM=COW  ...ork/CoreUtils
      __DATA_CONST             1d4450278-1d4453430 [   12K] r--/rw- SM=COW  .../FamilyCircle

Termination Reason: Namespace SPRINGBOARD, Code 0x8badf00d
Termination Description: SPRINGBOARD, <RBSTerminateContext| domain:10 code:0x8BADF00D explanation:scene-create watchdog transgression: application<ctrip.com>:444 exhausted real (wall clock) time allowance of 19.91 seconds | ProcessVisibility: Foreground | ProcessState: Running | WatchdogEvent: scene-create | WatchdogVisibility: Foreground | WatchdogCPUStatistics: ( | "Elapsed total CPU time (seconds): 19.580 (user 14.590, system 4.990), 16% CPU", | "Elapsed application CPU time (seconds): 0.034, 0% CPU" | ) reportType:CrashLog maxTerminationResistance:Interactive>
Triggered by Thread:  0

Thread 0 name:  Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0  MyApp                	0x0000000102d584bc perform_rebinding_with_section + 7177404 (fishhook.c:149)
1  MyApp                	0x0000000102d58460 perform_rebinding_with_section + 7177312 (fishhook.c:143)
2  MyApp                	0x0000000102d5816c rebind_symbols_for_image + 7176556 (fishhook.c:222)

[tirodkar]

@grp are there plans to merge these PR's?

google/EarlGrey#1641