syzbot


BUG: unable to handle kernel paging request in fuse_dev_do_write (4)

Status: premoderation: reported on 2025/11/15 21:25
Reported-by: syzbot+1dfdb08eaef3039a9bc5@syzkaller.appspotmail.com
First crash: 4d11h, last: 4d11h
Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 BUG: unable to handle kernel paging request in fuse_dev_do_write 8 18 861d 927d 0/2 auto-obsoleted due to no activity on 2023/09/03 17:45
android-54 BUG: unable to handle kernel paging request in fuse_dev_do_write 8 C 213 204d 1800d 0/2 upstream: reported C repro on 2020/12/15 11:21
android-49 BUG: unable to handle kernel paging request in fuse_dev_do_write 8 C 46 2224d 2413d 0/3 public: reported C repro on 2019/04/13 00:00
android-5-15 BUG: unable to handle kernel paging request in fuse_dev_do_write 8 2 862d 863d 0/2 auto-obsoleted due to no activity on 2023/10/10 01:15
android-5-10 BUG: unable to handle kernel paging request in fuse_dev_do_write (2) 8 1 726d 726d 0/2 auto-obsoleted due to no activity on 2024/02/23 07:02
android-6-1 BUG: unable to handle kernel paging request in fuse_dev_do_write origin:downstream 8 C done error 35 4d07h 916d 0/2 upstream: reported C repro on 2023/05/18 20:01
android-5-10 BUG: unable to handle kernel paging request in fuse_dev_do_write (3) 8 1 605d 605d 0/2 auto-obsoleted due to no activity on 2024/06/22 11:39
upstream KASAN: slab-out-of-bounds Write in fuse_dev_do_write fuse 23 C 6 84d 89d 29/29 fixed on 2025/10/29 21:02

Sample crash report:
BUG: unable to handle page fault for address: ffffed104c06c9ff
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 23fff2067 P4D 23fff2067 PUD 23fff0067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 27988 Comm: syz.4.69854 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:fuse_dev_do_write+0xe65/0x2af0 fs/fuse/dev.c:1953
Code: c1 e8 03 49 bc 00 00 00 00 00 fc ff df 42 0f b6 04 20 84 c0 0f 85 76 1a 00 00 45 8b 3f 41 ff cf 4d 01 f7 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 77 1a 00 00 41 c6 07 00 41 bf a0 00 00
RSP: 0018:ffffc90000f27900 EFLAGS: 00010a07
RAX: 1ffff1104c06c9ff RBX: 1ffff11024edb166 RCX: dffffc0000000000
RDX: ffffc90006c5b000 RSI: 0000000000000056 RDI: 0000000000000057
RBP: ffffc90000f27c08 R08: dffffc0000000000 R09: fffff94000b6e95f
R10: fffff94000b6e95f R11: 1ffffd4000b6e95e R12: dffffc0000000000
R13: 1ffff11024edb163 R14: ffff888160365000 R15: ffff888260364fff
FS:  00007f70414a86c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffed104c06c9ff CR3: 000000015ee2a000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fuse_dev_write+0xde/0x140 fs/fuse/dev.c:2003
 call_write_iter include/linux/fs.h:2066 [inline]
 new_sync_write fs/read_write.c:518 [inline]
 vfs_write+0x725/0xd60 fs/read_write.c:605
 ksys_write+0x140/0x240 fs/read_write.c:658
 __do_sys_write fs/read_write.c:670 [inline]
 __se_sys_write fs/read_write.c:667 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:667
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f7042a406c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f70414a8038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7042c96fa0 RCX: 00007f7042a406c9
RDX: 0000000000000010 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f7042ac2f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7042c97038 R14: 00007f7042c96fa0 R15: 00007ffed771e898
Modules linked in:
CR2: ffffed104c06c9ff
---[ end trace cf9640ed8fb838cb ]---
RIP: 0010:fuse_dev_do_write+0xe65/0x2af0 fs/fuse/dev.c:1953
Code: c1 e8 03 49 bc 00 00 00 00 00 fc ff df 42 0f b6 04 20 84 c0 0f 85 76 1a 00 00 45 8b 3f 41 ff cf 4d 01 f7 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 77 1a 00 00 41 c6 07 00 41 bf a0 00 00
RSP: 0018:ffffc90000f27900 EFLAGS: 00010a07
RAX: 1ffff1104c06c9ff RBX: 1ffff11024edb166 RCX: dffffc0000000000
RDX: ffffc90006c5b000 RSI: 0000000000000056 RDI: 0000000000000057
RBP: ffffc90000f27c08 R08: dffffc0000000000 R09: fffff94000b6e95f
R10: fffff94000b6e95f R11: 1ffffd4000b6e95e R12: dffffc0000000000
R13: 1ffff11024edb163 R14: ffff888160365000 R15: ffff888260364fff
FS:  00007f70414a86c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffed104c06c9ff CR3: 000000015ee2a000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	c1 e8 03             	shr    $0x3,%eax
   3:	49 bc 00 00 00 00 00 	movabs $0xdffffc0000000000,%r12
   a:	fc ff df
   d:	42 0f b6 04 20       	movzbl (%rax,%r12,1),%eax
  12:	84 c0                	test   %al,%al
  14:	0f 85 76 1a 00 00    	jne    0x1a90
  1a:	45 8b 3f             	mov    (%r15),%r15d
  1d:	41 ff cf             	dec    %r15d
  20:	4d 01 f7             	add    %r14,%r15
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 20       	movzbl (%rax,%r12,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 77 1a 00 00    	jne    0x1aae
  37:	41 c6 07 00          	movb   $0x0,(%r15)
  3b:	41                   	rex.B
  3c:	bf                   	.byte 0xbf
  3d:	a0                   	.byte 0xa0

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/15 21:25 android13-5.10-lts ab3e1c0dd1ff f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 BUG: unable to handle kernel paging request in fuse_dev_do_write
* Struck through repros no longer work on HEAD.