loop3: detected capacity change from 0 to 32768
general protection fault, probably for non-canonical address 0xdffffc00000000ba: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000005d0-0x00000000000005d7]
CPU: 0 PID: 4426 Comm: syz.3.74 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:blkg_tryget_closest block/blk-cgroup.c:1846 [inline]
RIP: 0010:bio_associate_blkg_from_css+0x2ab/0x9c0 block/blk-cgroup.c:1880
Code: ff df 80 3c 08 00 74 08 48 89 df e8 0f 2e ec 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 e7 2d ec fd bb 90 00 00 00 49 03 1e
RSP: 0018:ffffc90003e3f7b0 EFLAGS: 00010202
RAX: 00000000000000ba RBX: ffff88807d3cd288 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff8a79f7e0 RDI: ffffffff8a79f7a0
RBP: 1ffff1100fa79a59 R08: dffffc0000000000 R09: 1ffffffff203a618
R10: dffffc0000000000 R11: fffffbfff203a619 R12: ffff888078786110
R13: ffff88807d3cd2c8 R14: 00000000000005d0 R15: ffff8880293dbbac
FS:  0000555561f54500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb8893de000 CR3: 0000000023b9b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 bio_associate_blkg+0x23a/0x340 block/blk-cgroup.c:1908
 lbmStartIO+0x204/0x4c0 fs/jfs/jfs_logmgr.c:2130
 lbmWrite+0x361/0x480 fs/jfs/jfs_logmgr.c:2079
 lmNextPage+0x386/0xa00 fs/jfs/jfs_logmgr.c:-1
 lmWriteRecord+0xf9d/0x1aa0 fs/jfs/jfs_logmgr.c:537
 lmLog+0x6f6/0xa30 fs/jfs/jfs_logmgr.c:314
 logMOUNT fs/jfs/jfs_mount.c:495 [inline]
 jfs_mount_rw+0x3e6/0x5c0 fs/jfs/jfs_mount.c:268
 jfs_fill_super+0x5c1/0xb00 fs/jfs/super.c:570
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fcf9a556a0a
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007ffd4a3ac478 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffd4a3ac500 RCX: 00007fcf9a556a0a
RDX: 0000200000000000 RSI: 0000200000000080 RDI: 00007ffd4a3ac4c0
RBP: 0000200000000000 R08: 00007ffd4a3ac500 R09: 0000000000800000
R10: 0000000000800000 R11: 0000000000000246 R12: 0000200000000080
R13: 00007ffd4a3ac4c0 R14: 0000000000006197 R15: 00002000000000c0
 </TASK>
Modules linked in:
---[ end trace 6483adb20c1dfbbf ]---
RIP: 0010:blkg_tryget_closest block/blk-cgroup.c:1846 [inline]
RIP: 0010:bio_associate_blkg_from_css+0x2ab/0x9c0 block/blk-cgroup.c:1880
Code: ff df 80 3c 08 00 74 08 48 89 df e8 0f 2e ec 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 e7 2d ec fd bb 90 00 00 00 49 03 1e
RSP: 0018:ffffc90003e3f7b0 EFLAGS: 00010202
RAX: 00000000000000ba RBX: ffff88807d3cd288 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff8a79f7e0 RDI: ffffffff8a79f7a0
RBP: 1ffff1100fa79a59 R08: dffffc0000000000 R09: 1ffffffff203a618
R10: dffffc0000000000 R11: fffffbfff203a619 R12: ffff888078786110
R13: ffff88807d3cd2c8 R14: 00000000000005d0 R15: ffff8880293dbbac
FS:  0000555561f54500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb8893de000 CR3: 0000000023b9b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	ff                   	lcall  (bad)
   1:	df 80 3c 08 00 74    	filds  0x7400083c(%rax)
   7:	08 48 89             	or     %cl,-0x77(%rax)
   a:	df e8                	fucomip %st(0),%st
   c:	0f 2e ec             	ucomiss %xmm4,%xmm5
   f:	fd                   	std
  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 e7 2d ec fd       	call   0xfdec2e1f
  38:	bb 90 00 00 00       	mov    $0x90,%ebx
  3d:	49 03 1e             	add    (%r14),%rbx