general protection fault in fuse_atomic_open

Status: upstream: reported C repro on 2023/07/17 00:03
Bug presence: origin:downstream
[Documentation on labels]
Reported-by: syzbot+8e2c502cde30a2ac8d7f@syzkaller.appspotmail.com
First crash: 1210d, last: 6d18h
Cause bisection: introduced by (bisect log) :
commit 57f3ff9648991998d008ecf32f2f9e78a08bfb8b
Author: Daniel Rosenberg <drosen@google.com>
Date: Thu Dec 2 21:50:02 2021 +0000

  ANDROID: fuse-bpf v1.1

Crash: BUG: unable to handle kernel NULL pointer dereference in fuse_atomic_open (log)
Repro: C syz .config
  
Fix bisection: the issue occurs on the latest tested release (bisect log)
  
▶ ▼ Bug presence (3)
Date Name Commit Repro Result
2023/07/17 android14-6.1 (ToT) f6707f352b54 C [report] general protection fault in fuse_atomic_open
2023/07/17 lts (merge base) b1644a0031cf C Didn't crash
2023/07/17 upstream (ToT) fdf0eaf11452 C Didn't crash
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 general protection fault in fuse_atomic_open 2 syz, C error 107 28d 1210d 0/2 upstream: reported C repro on 2023/07/16 23:36
android-5-15 general protection fault in fuse_atomic_open (2) origin:downstream 2 syz, C done 46 37d 1198d 0/2 upstream: reported C repro on 2023/07/29 15:55
android-5-15 general protection fault in fuse_atomic_open 2 1 1316d 1316d 0/2 auto-obsoleted due to no activity on 2023/07/01 15:58
android-6-12 general protection fault in fuse_atomic_open origin:downstream 2 syz, C 30 1d08h 443d 0/1 premoderation: reported C repro on 2025/08/22 12:42
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/10/14 17:26 10m retest repro android14-6.1 report job log log
2026/10/14 17:26 10m retest repro android14-6.1 report job log log
2026/10/14 17:26 19m retest repro android14-6.1 report job log log
2026/10/14 17:26 41m retest repro android14-6.1 report job log log
2026/10/14 17:26 18m retest repro android14-6.1 report job log log
2026/08/19 07:17 3m retest repro android14-6.1 error job log
2026/08/19 07:17 3m retest repro android14-6.1 error job log
2026/08/19 07:17 8m retest repro android14-6.1 error job log
2026/08/19 07:17 3m retest repro android14-6.1 error job log
2026/08/19 07:17 3m retest repro android14-6.1 error job log
▶ ▼ Fix bisection attempts (9)
Created Duration User Patch Repo Result
2026/08/22 20:53 1h43m bisect fix android14-6.1 OK (0) job log
2025/02/15 20:16 49m bisect fix android14-6.1 OK (0) job log log
2024/10/03 20:51 3h02m bisect fix android14-6.1 OK (0) job log log
2024/07/25 03:34 1h08m bisect fix android14-6.1 OK (0) job log log
2024/03/15 18:49 1h45m bisect fix android14-6.1 OK (0) job log log
2024/02/11 21:56 1h06m bisect fix android14-6.1 OK (0) job log log
2023/12/23 20:59 46m bisect fix android14-6.1 OK (0) job log log
2023/10/25 03:10 1h01m bisect fix android14-6.1 OK (0) job log log
2023/09/22 00:58 38m bisect fix android14-6.1 OK (0) job log log

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000008: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000040-0x0000000000000047]
CPU: 1 PID: 307 Comm: syz-executor585 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:d_really_is_positive include/linux/dcache.h:493 [inline]
RIP: 0010:fuse_atomic_open+0x174/0x3c0 fs/fuse/dir.c:901
Code: 8b 6d c4 44 89 ee 83 e6 40 31 ff e8 96 b4 65 ff 44 89 e8 83 e0 40 75 07 e8 69 b0 65 ff eb 26 4d 8d 6e 30 4c 89 e8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ef e8 8d 4c ab ff 49 83 7d 00 00 74 21
RSP: 0018:ffffc90000e77918 EFLAGS: 00010202
RAX: 0000000000000008 RBX: ffff88810f5fd800 RCX: 0000000000000000
RDX: ffff88810f478000 RSI: 0000000000000040 RDI: 0000000000000000
RBP: ffffc90000e77970 R08: ffff88810f478000 R09: fffff520001cee98
R10: 00000000fffffffe R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000040 R14: 0000000000000010 R15: ffff888114d8bb80
FS:  00007efecda846c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efecda62bb0 CR3: 0000000122ecf000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 atomic_open fs/namei.c:3352 [inline]
 lookup_open fs/namei.c:3460 [inline]
 open_last_lookups fs/namei.c:3557 [inline]
 path_openat+0x125c/0x2f30 fs/namei.c:3787
 do_filp_open+0x1ee/0x420 fs/namei.c:3817
 do_sys_openat2+0x15e/0x820 fs/open.c:1343
 do_sys_open fs/open.c:1359 [inline]
 __do_sys_openat fs/open.c:1375 [inline]
 __se_sys_openat fs/open.c:1370 [inline]
 __x64_sys_openat+0x136/0x160 fs/open.c:1370
 x64_sys_call+0x783/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7efecdac40b9
Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 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 d0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007efecda84218 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007efecdb74b58 RCX: 00007efecdac40b9
RDX: 0000000000060a41 RSI: 00002000000013c0 RDI: 00000000ffffff9c
RBP: 00007efecdb74b50 R08: 33203a6b63617473 R09: 33203a6b63617473
R10: 0000000000005f29 R11: 0000000000000246 R12: 00007efecdb4241c
R13: 0000200000002140 R14: 00007ffdb6d56950 R15: 00007ffdb6d56a38
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:d_really_is_positive include/linux/dcache.h:493 [inline]
RIP: 0010:fuse_atomic_open+0x174/0x3c0 fs/fuse/dir.c:901
Code: 8b 6d c4 44 89 ee 83 e6 40 31 ff e8 96 b4 65 ff 44 89 e8 83 e0 40 75 07 e8 69 b0 65 ff eb 26 4d 8d 6e 30 4c 89 e8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ef e8 8d 4c ab ff 49 83 7d 00 00 74 21
RSP: 0018:ffffc90000e77918 EFLAGS: 00010202

RAX: 0000000000000008 RBX: ffff88810f5fd800 RCX: 0000000000000000
RDX: ffff88810f478000 RSI: 0000000000000040 RDI: 0000000000000000
RBP: ffffc90000e77970 R08: ffff88810f478000 R09: fffff520001cee98
R10: 00000000fffffffe R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000040 R14: 0000000000000010 R15: ffff888114d8bb80
FS:  00007efecda846c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000013c0 CR3: 0000000122ecf000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	8b 6d c4             	mov    -0x3c(%rbp),%ebp
   3:	44 89 ee             	mov    %r13d,%esi
   6:	83 e6 40             	and    $0x40,%esi
   9:	31 ff                	xor    %edi,%edi
   b:	e8 96 b4 65 ff       	call   0xff65b4a6
  10:	44 89 e8             	mov    %r13d,%eax
  13:	83 e0 40             	and    $0x40,%eax
  16:	75 07                	jne    0x1f
  18:	e8 69 b0 65 ff       	call   0xff65b086
  1d:	eb 26                	jmp    0x45
  1f:	4d 8d 6e 30          	lea    0x30(%r14),%r13
  23:	4c 89 e8             	mov    %r13,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 ef             	mov    %r13,%rdi
  34:	e8 8d 4c ab ff       	call   0xffab4cc6
  39:	49 83 7d 00 00       	cmpq   $0x0,0x0(%r13)
  3e:	74 21                	je     0x61

Crashes (33):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/11/02 01:09 android14-6.1 743bbe988cbf 25a0ae84 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/10/27 04:51 android14-6.1 e7e4a657fff8 168cb7a2 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/07/17 21:40 android14-6.1 c7e15f0bdc49 8aaff637 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/06/17 18:10 android14-6.1 9f35ca3ff66c b62b3ded .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/06/11 18:59 android14-6.1 bf32db543281 d93a6ab6 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/06/07 09:20 android14-6.1 d73749230104 cc095639 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/03/18 23:25 android14-6.1 6bdf05f15ab2 0199f9a1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/02/24 06:57 android14-6.1 34c1a8e17200 41d2fa6a .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/10/21 23:18 android14-6.1 22c0b7236c43 9832ed61 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/08/13 04:49 android14-6.1 c750dc582629 22ec1469 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/05/12 09:14 android14-6.1 646380b087a5 77908e5f .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/04/03 04:10 android14-6.1 3e6e324f5b47 c799dfdd .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2024/03/17 15:10 android14-6.1 ef39f76e4d24 d615901c .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2023/11/09 13:34 android14-6.1 9d6ac9dc6ac8 4862372a .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2023/07/17 00:01 android14-6.1 f6707f352b54 35d9ecc5 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/10/27 04:12 android14-6.1 e7e4a657fff8 168cb7a2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/06/07 05:42 android14-6.1 d73749230104 cc095639 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/05/23 12:50 android14-6.1 108b53924ea3 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/05/14 02:33 android14-6.1 17b41c3753e0 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2026/04/29 08:06 android14-6.1 2d8ef4f239b0 95008c03 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/12/23 15:10 android14-6.1 b952cc514e6f d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/11/23 14:38 android14-6.1 eba111621724 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/11/10 16:36 android14-6.1 50ba6c46f3ac 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/04/05 10:19 android14-6.1 ca24c52e3c25 c53ea9c9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/04/05 10:18 android14-6.1 ca24c52e3c25 c53ea9c9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/04/03 23:34 android14-6.1 ca24c52e3c25 d7ae3a11 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/04/03 23:34 android14-6.1 ca24c52e3c25 d7ae3a11 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/04/03 23:34 android14-6.1 ca24c52e3c25 d7ae3a11 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/04/03 23:34 android14-6.1 ca24c52e3c25 d7ae3a11 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/04/03 03:18 android14-6.1 3e6e324f5b47 c799dfdd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2025/04/03 03:18 android14-6.1 3e6e324f5b47 c799dfdd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2024/04/20 07:44 android14-6.1 dcb09569bbff af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
2024/03/17 14:53 android14-6.1 ef39f76e4d24 d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 general protection fault in fuse_atomic_open
* Struck through repros no longer work on HEAD.