syzbot

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 1 UID: 0 PID: 5974 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline]
RIP: 0010:lmLogSync+0x1f1/0x9d0 fs/jfs/jfs_logmgr.c:937
Code: 95 76 fe 4d 8d 7e d8 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 ad b5 dc fe 4d 8b 3f 49 83 c7 30 4c 89 f8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ff e8 91 b5 dc fe 49 8b 3f e8 29 8c ae fe
RSP: 0018:ffffc90003cefb60 EFLAGS: 00010216
RAX: 0000000000000006 RBX: dffffc0000000000 RCX: ffff88802d659e80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003cefc68 R08: ffffc90003cefaaf R09: ffffc90003cef948
R10: dffffc0000000000 R11: fffff5200079df56 R12: ffff888022778000
R13: dffffc0000000000 R14: ffff888077da7238 R15: 0000000000000030
FS:  000055556f167500(0000) GS:ffff888125f21000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd47ba9fe8 CR3: 00000000788ad000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 jfs_syncpt+0x7b/0x90 fs/jfs/jfs_logmgr.c:1041
 jfs_sync_fs+0x87/0xa0 fs/jfs/super.c:650
 sync_filesystem+0xee/0x230 fs/sync.c:56
 generic_shutdown_super+0x6f/0x2c0 fs/super.c:622
 kill_block_super+0x44/0x90 fs/super.c:1722
 deactivate_locked_super+0xbc/0x130 fs/super.c:474
 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1318
 task_work_run+0x1d4/0x260 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
 exit_to_user_mode_loop+0xef/0x4e0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f932bf90a77
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:00007ffd47baa248 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f932c013d7d RCX: 00007f932bf90a77
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd47baa300
RBP: 00007ffd47baa300 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd47bab390
R13: 00007f932c013d7d R14: 00000000000236a7 R15: 00007ffd47bab3d0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:207 [inline]
RIP: 0010:lmLogSync+0x1f1/0x9d0 fs/jfs/jfs_logmgr.c:937
Code: 95 76 fe 4d 8d 7e d8 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 ad b5 dc fe 4d 8b 3f 49 83 c7 30 4c 89 f8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ff e8 91 b5 dc fe 49 8b 3f e8 29 8c ae fe
RSP: 0018:ffffc90003cefb60 EFLAGS: 00010216
RAX: 0000000000000006 RBX: dffffc0000000000 RCX: ffff88802d659e80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003cefc68 R08: ffffc90003cefaaf R09: ffffc90003cef948
R10: dffffc0000000000 R11: fffff5200079df56 R12: ffff888022778000
R13: dffffc0000000000 R14: ffff888077da7238 R15: 0000000000000030
FS:  000055556f167500(0000) GS:ffff888125e21000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f748b480178 CR3: 00000000788ad000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	95                   	xchg   %eax,%ebp
   1:	76 fe                	jbe    0x1
   3:	4d 8d 7e d8          	lea    -0x28(%r14),%r15
   7:	4c 89 f8             	mov    %r15,%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 ff             	mov    %r15,%rdi
  17:	e8 ad b5 dc fe       	call   0xfedcb5c9
  1c:	4d 8b 3f             	mov    (%r15),%r15
  1f:	49 83 c7 30          	add    $0x30,%r15
  23:	4c 89 f8             	mov    %r15,%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 ff             	mov    %r15,%rdi
  33:	e8 91 b5 dc fe       	call   0xfedcb5c9
  38:	49 8b 3f             	mov    (%r15),%rdi
  3b:	e8 29 8c ae fe       	call   0xfeae8c69