syzbot


general protection fault in jfs_flush_journal

Status: upstream: reported on 2025/06/19 06:28
Reported-by: syzbot+eb664fd024256bc44597@syzkaller.appspotmail.com
First crash: 1d03h, last: 1d03h
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in jfs_flush_journal jfs C inconclusive 2334 9h40m 991d 0/29 upstream: reported C repro on 2022/10/02 18:56
linux-6.1 general protection fault in jfs_flush_journal origin:upstream C 121 2d13h 822d 0/3 upstream: reported C repro on 2023/03/20 13:13
linux-5.15 general protection fault in jfs_flush_journal origin:upstream C error 29 12d 826d 0/3 upstream: reported C repro on 2023/03/16 22:18

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: 0 PID: 5764 Comm: syz-executor Not tainted 6.6.93-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline]
RIP: 0010:jfs_flush_journal+0x7ae/0xeb0 fs/jfs/jfs_logmgr.c:1573
Code: 00 00 00 4d 8d 77 d8 4c 89 f0 48 c1 e8 03 80 3c 18 00 74 08 4c 89 f7 e8 d0 08 dd fe 4d 8b 26 49 83 c4 40 4c 89 e0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 e7 e8 b4 08 dd fe 49 8b 3c 24 e8 7b 2d b3
RSP: 0018:ffffc900046cfb20 EFLAGS: 00010202
RAX: 0000000000000008 RBX: dffffc0000000000 RCX: ffff88807d4e3c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900046cfc50 R08: 0000000000000004 R09: 0000000000000004
R10: ffffc900046cfa44 R11: fffff520008d9f51 R12: 0000000000000040
R13: ffff88805f77a9a8 R14: ffff88802b956210 R15: ffff88802b956238
FS:  0000555588904500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7b7179b000 CR3: 0000000062a65000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 jfs_umount+0x178/0x3c0 fs/jfs/jfs_umount.c:58
 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194
 generic_shutdown_super+0x134/0x2b0 fs/super.c:693
 kill_block_super+0x44/0x90 fs/super.c:1660
 deactivate_locked_super+0x97/0x100 fs/super.c:481
 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250
 task_work_run+0x1ce/0x250 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7faa1c18fc57
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffefe699cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007faa1c210925 RCX: 00007faa1c18fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffefe699db0
RBP: 00007ffefe699db0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffefe69ae40
R13: 00007faa1c210925 R14: 0000000000027306 R15: 00007ffefe69ae80
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline]
RIP: 0010:jfs_flush_journal+0x7ae/0xeb0 fs/jfs/jfs_logmgr.c:1573
Code: 00 00 00 4d 8d 77 d8 4c 89 f0 48 c1 e8 03 80 3c 18 00 74 08 4c 89 f7 e8 d0 08 dd fe 4d 8b 26 49 83 c4 40 4c 89 e0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 e7 e8 b4 08 dd fe 49 8b 3c 24 e8 7b 2d b3
RSP: 0018:ffffc900046cfb20 EFLAGS: 00010202
RAX: 0000000000000008 RBX: dffffc0000000000 RCX: ffff88807d4e3c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900046cfc50 R08: 0000000000000004 R09: 0000000000000004
R10: ffffc900046cfa44 R11: fffff520008d9f51 R12: 0000000000000040
R13: ffff88805f77a9a8 R14: ffff88802b956210 R15: ffff88802b956238
FS:  0000555588904500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000004000 CR3: 0000000062a65000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	00 4d 8d             	add    %cl,-0x73(%rbp)
   5:	77 d8                	ja     0xffffffdf
   7:	4c 89 f0             	mov    %r14,%rax
   a:	48 c1 e8 03          	shr    $0x3,%rax
   e:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1)
  12:	74 08                	je     0x1c
  14:	4c 89 f7             	mov    %r14,%rdi
  17:	e8 d0 08 dd fe       	call   0xfedd08ec
  1c:	4d 8b 26             	mov    (%r14),%r12
  1f:	49 83 c4 40          	add    $0x40,%r12
  23:	4c 89 e0             	mov    %r12,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	4c 89 e7             	mov    %r12,%rdi
  33:	e8 b4 08 dd fe       	call   0xfedd08ec
  38:	49 8b 3c 24          	mov    (%r12),%rdi
  3c:	e8                   	.byte 0xe8
  3d:	7b 2d                	jnp    0x6c
  3f:	b3                   	.byte 0xb3

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/19 06:27 linux-6.6.y c2603c511feb ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan general protection fault in jfs_flush_journal
* Struck through repros no longer work on HEAD.