syzbot


general protection fault in ovl_lookup_single

Status: auto-obsoleted due to no activity on 2024/04/07 02:55
Reported-by: syzbot+e6773379c649c9375cfb@syzkaller.appspotmail.com
First crash: 331d, last: 331d

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
CPU: 0 PID: 13799 Comm: syz-executor.3 Not tainted 6.1.57-syzkaller-00121-gac90f0829243 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
RIP: 0010:ovl_lookup_positive_unlocked fs/overlayfs/namei.c:209 [inline]
RIP: 0010:ovl_lookup_single+0x156/0x9f0 fs/overlayfs/namei.c:233
Code: 49 bf 00 00 00 00 00 fc ff df e9 9b 04 00 00 48 89 5c 24 20 44 88 6c 24 10 4d 89 f5 49 c1 ed 03 48 b8 00 00 00 00 00 fc ff df <41> 0f b6 44 05 00 84 c0 0f 85 a1 06 00 00 45 8b 3e bb 00 00 70 00
RSP: 0018:ffffc9000d9972a0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffffc9000d997688 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000001
RBP: ffffc9000d997380 R08: dffffc0000000000 R09: ffffed1023fbe09d
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92001b32ed1
R13: 0000000000000002 R14: 0000000000000010 R15: ffff88811a9ea038
FS:  00007fa2b63ff6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020001000 CR3: 0000000141e94000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ovl_lookup_layer+0x413/0x510 fs/overlayfs/namei.c:320
 ovl_lookup+0xd46/0x2340 fs/overlayfs/namei.c:923
 __lookup_slow+0x2b9/0x3e0 fs/namei.c:1685
 lookup_slow+0x5a/0x80 fs/namei.c:1702
 walk_component+0x2e7/0x410 fs/namei.c:1993
 lookup_last fs/namei.c:2450 [inline]
 path_lookupat+0x16d/0x450 fs/namei.c:2474
 filename_lookup+0x251/0x600 fs/namei.c:2503
 vfs_statx+0x107/0x4b0 fs/stat.c:229
 vfs_fstatat fs/stat.c:267 [inline]
 vfs_lstat include/linux/fs.h:3323 [inline]
 __do_sys_newlstat fs/stat.c:423 [inline]
 __se_sys_newlstat+0xda/0x7c0 fs/stat.c:417
 __x64_sys_newlstat+0x5b/0x70 fs/stat.c:417
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fa2b707cd29
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa2b63ff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000006
RAX: ffffffffffffffda RBX: 00007fa2b71ac050 RCX: 00007fa2b707cd29
RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000020000240
RBP: 00007fa2b70c947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007fa2b71ac050 R15: 00007ffc7012f8b8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ovl_lookup_positive_unlocked fs/overlayfs/namei.c:209 [inline]
RIP: 0010:ovl_lookup_single+0x156/0x9f0 fs/overlayfs/namei.c:233
Code: 49 bf 00 00 00 00 00 fc ff df e9 9b 04 00 00 48 89 5c 24 20 44 88 6c 24 10 4d 89 f5 49 c1 ed 03 48 b8 00 00 00 00 00 fc ff df <41> 0f b6 44 05 00 84 c0 0f 85 a1 06 00 00 45 8b 3e bb 00 00 70 00
RSP: 0018:ffffc9000d9972a0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffffc9000d997688 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000001
RBP: ffffc9000d997380 R08: dffffc0000000000 R09: ffffed1023fbe09d
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92001b32ed1
R13: 0000000000000002 R14: 0000000000000010 R15: ffff88811a9ea038
FS:  00007fa2b63ff6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2dc22000 CR3: 0000000141e94000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	49 bf 00 00 00 00 00 	movabs $0xdffffc0000000000,%r15
   7:	fc ff df
   a:	e9 9b 04 00 00       	jmp    0x4aa
   f:	48 89 5c 24 20       	mov    %rbx,0x20(%rsp)
  14:	44 88 6c 24 10       	mov    %r13b,0x10(%rsp)
  19:	4d 89 f5             	mov    %r14,%r13
  1c:	49 c1 ed 03          	shr    $0x3,%r13
  20:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  27:	fc ff df
* 2a:	41 0f b6 44 05 00    	movzbl 0x0(%r13,%rax,1),%eax <-- trapping instruction
  30:	84 c0                	test   %al,%al
  32:	0f 85 a1 06 00 00    	jne    0x6d9
  38:	45 8b 3e             	mov    (%r14),%r15d
  3b:	bb 00 00 70 00       	mov    $0x700000,%ebx

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/01/08 02:48 android14-6.1 ac90f0829243 d0304e9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in ovl_lookup_single
* Struck through repros no longer work on HEAD.