syzbot


general protection fault in vfs_link

Status: upstream: reported C repro on 2024/02/20 15:20
Reported-by: syzbot+e5eaf9353175ccba55df@syzkaller.appspotmail.com
First crash: 120d, last: 36d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-6-1 general protection fault in vfs_link origin:downstream C 1 23d 117d 0/2 upstream: reported C repro on 2024/02/23 21:10
android-5-15 general protection fault in vfs_link origin:downstream C 1 22d 116d 0/2 upstream: reported C repro on 2024/02/24 15:03
android-5-10 general protection fault in vfs_link C inconclusive 3 67d 127d 0/2 upstream: reported C repro on 2024/02/13 06:42
Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/05/14 17:34 11m retest repro android12-5.4 report log
2024/03/05 15:26 12m retest repro android12-5.4 report log

Sample crash report:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 368 Comm: syz-executor147 Not tainted 5.4.265-syzkaller-00001-g1b3143b9b166 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
RIP: 0010:vfs_link+0x3b/0x8a0 fs/namei.c:4298
Code: 24 30 49 89 d6 49 89 f5 48 89 fb 48 bd 00 00 00 00 00 fc ff df e8 b5 1c c6 ff 48 89 5c 24 28 48 83 c3 30 48 89 d8 48 c1 e8 03 <80> 3c 28 00 74 08 48 89 df e8 47 ef f5 ff 48 8b 2b 4d 8d 7d 28 4d
RSP: 0018:ffff8881dcb8fbb0 EFLAGS: 00010206
RAX: 0000000000000006 RBX: 0000000000000030 RCX: ffff8881dc858fc0
RDX: 0000000000000000 RSI: ffff8881e83f2518 RDI: 0000000000000000
RBP: dffffc0000000000 R08: dffffc0000000000 R09: ffffed103d07e4b9
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8881e83fe990
R13: ffff8881e83f2518 R14: ffff8881e83fe990 R15: ffff8881e83f2518
FS:  0000555556cda480(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 00000001dca27000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 incfs_link fs/incfs/vfs.c:603 [inline]
 dir_link+0x37f/0x510 fs/incfs/vfs.c:1278
 vfs_link+0x69b/0x8a0 fs/namei.c:4342
 do_linkat+0x46c/0x8b0 fs/namei.c:4410
 __do_sys_linkat fs/namei.c:4434 [inline]
 __se_sys_linkat fs/namei.c:4431 [inline]
 __x64_sys_linkat+0xb1/0xc0 fs/namei.c:4431
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
Modules linked in:
---[ end trace 52481c0c82d34b71 ]---
RIP: 0010:vfs_link+0x3b/0x8a0 fs/namei.c:4298
Code: 24 30 49 89 d6 49 89 f5 48 89 fb 48 bd 00 00 00 00 00 fc ff df e8 b5 1c c6 ff 48 89 5c 24 28 48 83 c3 30 48 89 d8 48 c1 e8 03 <80> 3c 28 00 74 08 48 89 df e8 47 ef f5 ff 48 8b 2b 4d 8d 7d 28 4d
RSP: 0018:ffff8881dcb8fbb0 EFLAGS: 00010206
RAX: 0000000000000006 RBX: 0000000000000030 RCX: ffff8881dc858fc0
RDX: 0000000000000000 RSI: ffff8881e83f2518 RDI: 0000000000000000
RBP: dffffc0000000000 R08: dffffc0000000000 R09: ffffed103d07e4b9
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8881e83fe990
R13: ffff8881e83f2518 R14: ffff8881e83fe990 R15: ffff8881e83f2518
FS:  0000555556cda480(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 00000001dca27000 CR4: 00000000003406a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	24 30                	and    $0x30,%al
   2:	49 89 d6             	mov    %rdx,%r14
   5:	49 89 f5             	mov    %rsi,%r13
   8:	48 89 fb             	mov    %rdi,%rbx
   b:	48 bd 00 00 00 00 00 	movabs $0xdffffc0000000000,%rbp
  12:	fc ff df
  15:	e8 b5 1c c6 ff       	call   0xffc61ccf
  1a:	48 89 5c 24 28       	mov    %rbx,0x28(%rsp)
  1f:	48 83 c3 30          	add    $0x30,%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	80 3c 28 00          	cmpb   $0x0,(%rax,%rbp,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	48 89 df             	mov    %rbx,%rdi
  33:	e8 47 ef f5 ff       	call   0xfff5ef7f
  38:	48 8b 2b             	mov    (%rbx),%rbp
  3b:	4d 8d 7d 28          	lea    0x28(%r13),%r15
  3f:	4d                   	rex.WRB

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/02/20 15:19 android12-5.4 1b3143b9b166 3af7dd65 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-5-4-kasan general protection fault in vfs_link
* Struck through repros no longer work on HEAD.