syzbot

find_entry called with index = 0
jfs_dirty_inode called on read-only volume
Is remount racy?
jfs_dirty_inode called on read-only volume
Is remount racy?
Oops: general protection fault, probably for non-canonical address 0xdffffc00000000f3: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000798-0x000000000000079f]
CPU: 0 UID: 0 PID: 5957 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:JFS_SBI fs/jfs/jfs_incore.h:217 [inline]
RIP: 0010:txEnd+0xb4/0x530 fs/jfs/jfs_txnmgr.c:507
Code: 49 8d 5e 20 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 ec fc d5 fe 41 bf 98 07 00 00 4c 03 3b 4c 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 ff e8 cd fc d5 fe 49 8b 1f 48 83 c3 30
RSP: 0018:ffffc90004037660 EFLAGS: 00010206
RAX: 00000000000000f3 RBX: ffffc90003279020 RCX: 0000000000000000
RDX: 0000000000000006 RSI: ffffffff8d566031 RDI: 00000000ffffffff
RBP: ffffc900040378f0 R08: ffffffff8f6a78b7 R09: 1ffffffff1ed4f16
R10: dffffc0000000000 R11: fffffbfff1ed4f17 R12: 00000000ffffffe2
R13: dffffc0000000000 R14: ffffc90003279000 R15: 0000000000000798
FS:  000055558eaa6500(0000) GS:ffff888126332000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd5df815000 CR3: 000000003e54a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 jfs_create+0x377/0xb10 fs/jfs/namei.c:160
 lookup_open fs/namei.c:4489 [inline]
 open_last_lookups fs/namei.c:4589 [inline]
 path_openat+0x13b4/0x38a0 fs/namei.c:4833
 do_file_open+0x23e/0x4a0 fs/namei.c:4865
 do_sys_openat2+0x113/0x200 fs/open.c:1366
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_creat fs/open.c:1450 [inline]
 __se_sys_creat fs/open.c:1444 [inline]
 __x64_sys_creat+0x8f/0xc0 fs/open.c:1444
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1cda06c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc270794a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f1cda2e5fa0 RCX: 00007f1cda06c819
RDX: 0000000000000000 RSI: 0000000000000041 RDI: 0000200000001f80
RBP: 00007f1cda102c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1cda2e5fac R14: 00007f1cda2e5fa0 R15: 00007f1cda2e5fa0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:JFS_SBI fs/jfs/jfs_incore.h:217 [inline]
RIP: 0010:txEnd+0xb4/0x530 fs/jfs/jfs_txnmgr.c:507
Code: 49 8d 5e 20 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 ec fc d5 fe 41 bf 98 07 00 00 4c 03 3b 4c 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 ff e8 cd fc d5 fe 49 8b 1f 48 83 c3 30
RSP: 0018:ffffc90004037660 EFLAGS: 00010206
RAX: 00000000000000f3 RBX: ffffc90003279020 RCX: 0000000000000000
RDX: 0000000000000006 RSI: ffffffff8d566031 RDI: 00000000ffffffff
RBP: ffffc900040378f0 R08: ffffffff8f6a78b7 R09: 1ffffffff1ed4f16
R10: dffffc0000000000 R11: fffffbfff1ed4f17 R12: 00000000ffffffe2
R13: dffffc0000000000 R14: ffffc90003279000 R15: 0000000000000798
FS:  000055558eaa6500(0000) GS:ffff888126332000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd5df815000 CR3: 000000003e54a000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	49 8d 5e 20          	lea    0x20(%r14),%rbx
   4:	48 89 d8             	mov    %rbx,%rax
   7:	48 c1 e8 03          	shr    $0x3,%rax
   b:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1)
  10:	74 08                	je     0x1a
  12:	48 89 df             	mov    %rbx,%rdi
  15:	e8 ec fc d5 fe       	call   0xfed5fd06
  1a:	41 bf 98 07 00 00    	mov    $0x798,%r15d
  20:	4c 03 3b             	add    (%rbx),%r15
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 ff             	mov    %r15,%rdi
  34:	e8 cd fc d5 fe       	call   0xfed5fd06
  39:	49 8b 1f             	mov    (%r15),%rbx
  3c:	48 83 c3 30          	add    $0x30,%rbx