syzbot


general protection fault in do_unlinkat

Status: upstream: reported C repro on 2023/07/01 22:19
Bug presence: origin:downstream
[Documentation on labels]
Reported-by: syzbot+401c1e2e29c32961e4bd@syzkaller.appspotmail.com
First crash: 944d, last: 3d05h
Cause bisection: introduced by (bisect log) :
commit f5f4199c102aa676998b42abff60d071385c1c0c
Author: Daniel Rosenberg <drosen@google.com>
Date: Thu Dec 2 21:50:02 2021 +0000

  ANDROID: fuse-bpf v1.1

Crash: general protection fault in do_unlinkat (log)
Repro: C syz .config
  
Bug presence (3)
Date Name Commit Repro Result
2023/07/05 android13-5.15-lts (ToT) 241da2ad5601 C [report] general protection fault in do_unlinkat
2023/07/05 lts (merge base) f67653019430 C Didn't crash
2023/07/05 upstream (ToT) d528014517f2 C Didn't crash
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 general protection fault in do_unlinkat 2 C done 50 2d16h 944d 0/2 upstream: reported C repro on 2023/07/01 21:31
android-6-12 general protection fault in do_unlinkat origin:downstream 2 C 5 113d 199d 0/1 premoderation: reported C repro on 2025/07/15 16:32
android-6-1 general protection fault in do_unlinkat origin:downstream 2 C done 9 3d00h 944d 0/2 upstream: reported C repro on 2023/07/01 22:19
Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/01/15 02:03 17m retest repro android13-5.15-lts report log
2026/01/15 02:03 18m retest repro android13-5.15-lts report log
2026/01/15 02:03 14m retest repro android13-5.15-lts report log
2025/12/31 17:05 12m retest repro android13-5.15-lts report log
2025/12/17 01:33 12m retest repro android13-5.15-lts report log
2025/12/17 01:33 16m retest repro android13-5.15-lts report log
2025/11/27 14:39 14m retest repro android13-5.15-lts report log
2025/11/27 14:39 12m retest repro android13-5.15-lts report log
2025/11/05 22:13 20m retest repro android13-5.15-lts report log
2025/11/05 22:13 19m retest repro android13-5.15-lts report log
Fix bisection attempts (10)
Created Duration User Patch Repo Result
2024/09/17 13:13 1h22m bisect fix android13-5.15-lts OK (0) job log log
2024/07/11 16:28 1h26m bisect fix android13-5.15-lts OK (0) job log log
2024/05/18 03:36 33m bisect fix android13-5.15-lts OK (0) job log log
2024/03/24 11:03 33m bisect fix android13-5.15-lts OK (0) job log log
2024/02/23 09:37 55m bisect fix android13-5.15-lts OK (0) job log log
2024/01/14 09:47 59m bisect fix android13-5.15-lts OK (0) job log log
2023/12/12 22:13 1h08m bisect fix android13-5.15-lts OK (0) job log log
2023/11/12 14:11 35m bisect fix android13-5.15-lts OK (0) job log log
2023/10/12 05:03 33m bisect fix android13-5.15-lts OK (0) job log log
2023/09/11 07:30 33m bisect fix android13-5.15-lts OK (0) job log log

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 0 PID: 377 Comm: syz.2.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:do_unlinkat+0x288/0x6d0 fs/namei.c:4348
Code: 44 89 ee e8 ea ee b5 ff 45 31 e4 41 81 fd 00 00 20 00 41 0f 95 c4 41 83 c4 eb e9 bd 00 00 00 49 8d 7e 30 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 4c 8b 7c 24 18 74 05 e8 f7 15 f5 ff 49 8b 46 30 48
RSP: 0018:ffffc90002c87e00 EFLAGS: 00010207
RAX: 0000000000000006 RBX: 1ffff11021a07b7c RCX: ffff888110bdbb40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000037
RBP: ffffc90002c87ee8 R08: ffff88810d03dc0f R09: 1ffff11021a07b81
R10: dffffc0000000000 R11: ffffed1021a07b82 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000007 R15: 0000000000000000
FS:  00007fc262c4c6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc262c4bff8 CR3: 000000011d4bc000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __do_sys_unlink fs/namei.c:4404 [inline]
 __se_sys_unlink fs/namei.c:4402 [inline]
 __x64_sys_unlink+0x49/0x50 fs/namei.c:4402
 x64_sys_call+0x878/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc262e08eb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc262c4c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007fc263084090 RCX: 00007fc262e08eb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000100
RBP: 00007fc262e76c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc263084128 R14: 00007fc263084090 R15: 00007ffedae5dd18
 </TASK>
Modules linked in:
---[ end trace 924bc3028bf43737 ]---
RIP: 0010:do_unlinkat+0x288/0x6d0 fs/namei.c:4348
Code: 44 89 ee e8 ea ee b5 ff 45 31 e4 41 81 fd 00 00 20 00 41 0f 95 c4 41 83 c4 eb e9 bd 00 00 00 49 8d 7e 30 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 4c 8b 7c 24 18 74 05 e8 f7 15 f5 ff 49 8b 46 30 48
RSP: 0018:ffffc90002c87e00 EFLAGS: 00010207
RAX: 0000000000000006 RBX: 1ffff11021a07b7c RCX: ffff888110bdbb40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000037
RBP: ffffc90002c87ee8 R08: ffff88810d03dc0f R09: 1ffff11021a07b81
R10: dffffc0000000000 R11: ffffed1021a07b82 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000007 R15: 0000000000000000
FS:  00007fc262c4c6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc262c4bff8 CR3: 000000011d4bc000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	44 89 ee             	mov    %r13d,%esi
   3:	e8 ea ee b5 ff       	call   0xffb5eef2
   8:	45 31 e4             	xor    %r12d,%r12d
   b:	41 81 fd 00 00 20 00 	cmp    $0x200000,%r13d
  12:	41 0f 95 c4          	setne  %r12b
  16:	41 83 c4 eb          	add    $0xffffffeb,%r12d
  1a:	e9 bd 00 00 00       	jmp    0xdc
  1f:	49 8d 7e 30          	lea    0x30(%r14),%rdi
  23:	48 89 f8             	mov    %rdi,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1) <-- trapping instruction
  2f:	4c 8b 7c 24 18       	mov    0x18(%rsp),%r15
  34:	74 05                	je     0x3b
  36:	e8 f7 15 f5 ff       	call   0xfff51632
  3b:	49 8b 46 30          	mov    0x30(%r14),%rax
  3f:	48                   	rex.W

Crashes (14):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/28 03:37 android13-5.15-lts 7e1070528954 3029c699 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2025/09/03 15:24 android13-5.15-lts da3dbfdd15be 96a211bc .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2025/06/19 07:00 android13-5.15-lts e678c93d43cc ed3e87f7 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2025/01/11 15:46 android13-5.15-lts 19092c8155b4 6dbc6a9b .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2025/01/06 16:21 android13-5.15-lts 19092c8155b4 f3558dbf .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2024/11/24 12:09 android13-5.15-lts 101e665d55a8 68da6d95 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2024/08/02 09:49 android13-5.15-lts 70e1a731d986 1e9c4cf3 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2024/03/31 00:41 android13-5.15-lts 993bed180178 6baf5069 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2023/07/01 22:18 android13-5.15-lts 241da2ad5601 bfc47836 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2025/12/02 18:25 android13-5.15-lts 057fdbf6d3c7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2025/12/02 18:25 android13-5.15-lts 057fdbf6d3c7 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2024/11/24 11:34 android13-5.15-lts 101e665d55a8 68da6d95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2024/10/13 23:31 android13-5.15-lts 5e4635681cf1 084d8178 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
2024/08/02 09:06 android13-5.15-lts 70e1a731d986 1e9c4cf3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in do_unlinkat
* Struck through repros no longer work on HEAD.