syzbot

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 0 UID: 0 PID: 5959 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:208 [inline]
RIP: 0010:lmLogSync+0x22e/0x9d0 fs/jfs/jfs_logmgr.c:937
Code: 90 bd fe 4d 8d 7e f0 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 50 5a e6 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 34 5a e6 fe 49 8b 3f e8 cc 8f bd fe
RSP: 0018:ffffc9000464fb80 EFLAGS: 00010206
RAX: 0000000000000006 RBX: dffffc0000000000 RCX: ffff88803055d940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000464fc88 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc9000464f968 R11: fffff520008c9f5a R12: 0000000000000000
R13: ffff888028c38000 R14: ffff888035962e38 R15: 0000000000000030
FS:  000055557b0e3500(0000) GS:ffff8881268bc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa85dd75000 CR3: 000000001b2be000 CR4: 00000000003526f0
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+0x1ce/0x250 fs/sync.c:66
 generic_shutdown_super+0x6f/0x2c0 fs/super.c:622
 kill_block_super+0x44/0x90 fs/super.c:1766
 deactivate_locked_super+0xb9/0x130 fs/super.c:474
 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1375
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8c596401f7
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:00007ffdd17e13e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f8c596c1d7d RCX: 00007f8c596401f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdd17e14a0
RBP: 00007ffdd17e14a0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdd17e2530
R13: 00007f8c596c1d7d R14: 0000000000025a19 R15: 00007ffdd17e2570
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:write_special_inodes fs/jfs/jfs_logmgr.c:208 [inline]
RIP: 0010:lmLogSync+0x22e/0x9d0 fs/jfs/jfs_logmgr.c:937
Code: 90 bd fe 4d 8d 7e f0 4c 89 f8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ff e8 50 5a e6 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 34 5a e6 fe 49 8b 3f e8 cc 8f bd fe
RSP: 0018:ffffc9000464fb80 EFLAGS: 00010206
RAX: 0000000000000006 RBX: dffffc0000000000 RCX: ffff88803055d940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000464fc88 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc9000464f968 R11: fffff520008c9f5a R12: 0000000000000000
R13: ffff888028c38000 R14: ffff888035962e38 R15: 0000000000000030
FS:  000055557b0e3500(0000) GS:ffff8881268bc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa85dd75000 CR3: 000000001b2be000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	90                   	nop
   1:	bd fe 4d 8d 7e       	mov    $0x7e8d4dfe,%ebp
   6:	f0 4c 89 f8          	lock 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 50 5a e6 fe       	call   0xfee65a6c
  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 34 5a e6 fe       	call   0xfee65a6c
  38:	49 8b 3f             	mov    (%r15),%rdi
  3b:	e8 cc 8f bd fe       	call   0xfebd900c