general protection fault, probably for non-canonical address 0xdffffc00000000ba: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000005d0-0x00000000000005d7]
CPU: 1 PID: 4824 Comm: kworker/u4:12 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: writeback wb_workfn (flush-7:5)
RIP: 0010:bio_associate_blkg_from_css+0x128/0x9c0 block/blk-cgroup.c:1878
Code: df 41 80 3c 04 00 74 08 48 89 df e8 b2 fb f2 fd 41 be d0 05 00 00 4c 03 33 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 f7 e8 8a fb f2 fd 41 bf 90 00 00 00 4d 03
RSP: 0018:ffffc9000320f260 EFLAGS: 00010202
RAX: 00000000000000ba RBX: ffff888060f3fdc8 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff96269dc0 RDI: ffff888060f3fdc0
RBP: 1ffff1100c1e7fc1 R08: dffffc0000000000 R09: fffffbfff1ff7619
R10: fffffbfff1ff7619 R11: 1ffffffff1ff7618 R12: 1ffff1100c1e7fb9
R13: ffff888060f3fe08 R14: 00000000000005d0 R15: ffff888063f1bbac
FS:  0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555584f935c8 CR3: 000000006693f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 bio_associate_blkg+0x23a/0x340 block/blk-cgroup.c:1904
 lbmStartIO+0x204/0x4c0 fs/jfs/jfs_logmgr.c:2130
 lbmWrite+0x361/0x480 fs/jfs/jfs_logmgr.c:2079
 lmGCwrite fs/jfs/jfs_logmgr.c:-1 [inline]
 jfs_flush_journal+0x535/0xeb0 fs/jfs/jfs_logmgr.c:1556
 jfs_write_inode+0x12b/0x220 fs/jfs/inode.c:128
 write_inode fs/fs-writeback.c:1495 [inline]
 __writeback_single_inode+0x6c3/0xda0 fs/fs-writeback.c:1705
 writeback_sb_inodes+0x9fe/0x1610 fs/fs-writeback.c:1930
 wb_writeback+0x443/0xb90 fs/fs-writeback.c:2104
 wb_do_writeback fs/fs-writeback.c:2247 [inline]
 wb_workfn+0x423/0xe60 fs/fs-writeback.c:2288
 process_one_work+0x863/0x1000 kernel/workqueue.c:2310
 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Modules linked in:
---[ end trace d8d2c7f66420ae78 ]---
RIP: 0010:bio_associate_blkg_from_css+0x128/0x9c0 block/blk-cgroup.c:1878
Code: df 41 80 3c 04 00 74 08 48 89 df e8 b2 fb f2 fd 41 be d0 05 00 00 4c 03 33 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 f7 e8 8a fb f2 fd 41 bf 90 00 00 00 4d 03
RSP: 0018:ffffc9000320f260 EFLAGS: 00010202
RAX: 00000000000000ba RBX: ffff888060f3fdc8 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff96269dc0 RDI: ffff888060f3fdc0
RBP: 1ffff1100c1e7fc1 R08: dffffc0000000000 R09: fffffbfff1ff7619
R10: fffffbfff1ff7619 R11: 1ffffffff1ff7618 R12: 1ffff1100c1e7fb9
R13: ffff888060f3fe08 R14: 00000000000005d0 R15: ffff888063f1bbac
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc7b0d58ad8 CR3: 0000000029a7c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	df 41 80             	filds  -0x80(%rcx)
   3:	3c 04                	cmp    $0x4,%al
   5:	00 74 08 48          	add    %dh,0x48(%rax,%rcx,1)
   9:	89 df                	mov    %ebx,%edi
   b:	e8 b2 fb f2 fd       	call   0xfdf2fbc2
  10:	41 be d0 05 00 00    	mov    $0x5d0,%r14d
  16:	4c 03 33             	add    (%rbx),%r14
  19:	4c 89 f0             	mov    %r14,%rax
  1c:	48 c1 e8 03          	shr    $0x3,%rax
  20:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  27:	fc ff df
* 2a:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	4c 89 f7             	mov    %r14,%rdi
  33:	e8 8a fb f2 fd       	call   0xfdf2fbc2
  38:	41 bf 90 00 00 00    	mov    $0x90,%r15d
  3e:	4d                   	rex.WRB
  3f:	03                   	.byte 0x3