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: 7616 Comm: syz.3.679 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:blkg_tryget_closest block/blk-cgroup.c:1842 [inline]
RIP: 0010:bio_associate_blkg_from_css+0x2ab/0x9c0 block/blk-cgroup.c:1876
Code: ff df 80 3c 08 00 74 08 48 89 df e8 9f f9 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 77 f9 f2 fd bb 90 00 00 00 49 03 1e
RSP: 0018:ffffc900037cf740 EFLAGS: 00010202
RAX: 00000000000000ba RBX: ffff8880774573c8 RCX: dffffc0000000000
RDX: ffffc9000ccb1000 RSI: 000000000000e05e RDI: 000000000000e05f
RBP: 1ffff1100ee8ae81 R08: dffffc0000000000 R09: fffffbfff1ff5419
R10: fffffbfff1ff5419 R11: 1ffffffff1ff5418 R12: ffff88807728a110
R13: ffff888077457408 R14: 00000000000005d0 R15: ffff88801dc63bac
FS:  00007f4d3a2df6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000f000 CR3: 0000000068503000 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: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]
 lmGroupCommit+0x5b5/0xb60 fs/jfs/jfs_logmgr.c:695
 txCommit+0x4711/0x51c0 fs/jfs/jfs_txnmgr.c:1305
 jfs_truncate_nolock+0x1ef/0x2d0 fs/jfs/inode.c:416
 jfs_truncate+0xca/0x140 fs/jfs/inode.c:429
 jfs_setattr+0x3e4/0x610 fs/jfs/file.c:122
 notify_change+0xbcd/0xee0 fs/attr.c:505
 do_truncate+0x197/0x220 fs/open.c:65
 do_sys_ftruncate+0x31b/0x3d0 fs/open.c:193
 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: 0033:0x7f4d3c078749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4d3a2df038 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 00007f4d3c2cefa0 RCX: 00007f4d3c078749
RDX: 0000000000000000 RSI: 0000000000000f88 RDI: 000000000000000a
RBP: 00007f4d3c0fcf91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4d3c2cf038 R14: 00007f4d3c2cefa0 R15: 00007ffd6e2fec08
 </TASK>
Modules linked in:
---[ end trace 9486776cd5503b6f ]---
RIP: 0010:blkg_tryget_closest block/blk-cgroup.c:1842 [inline]
RIP: 0010:bio_associate_blkg_from_css+0x2ab/0x9c0 block/blk-cgroup.c:1876
Code: ff df 80 3c 08 00 74 08 48 89 df e8 9f f9 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 77 f9 f2 fd bb 90 00 00 00 49 03 1e
RSP: 0018:ffffc900037cf740 EFLAGS: 00010202
RAX: 00000000000000ba RBX: ffff8880774573c8 RCX: dffffc0000000000
RDX: ffffc9000ccb1000 RSI: 000000000000e05e RDI: 000000000000e05f
RBP: 1ffff1100ee8ae81 R08: dffffc0000000000 R09: fffffbfff1ff5419
R10: fffffbfff1ff5419 R11: 1ffffffff1ff5418 R12: ffff88807728a110
R13: ffff888077457408 R14: 00000000000005d0 R15: ffff88801dc63bac
FS:  00007f4d3a2df6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4d32e9d000 CR3: 0000000068503000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	df 80 3c 08 00 74    	filds  0x7400083c(%rax)
   6:	08 48 89             	or     %cl,-0x77(%rax)
   9:	df e8                	fucomip %st(0),%st
   b:	9f                   	lahf
   c:	f9                   	stc
   d:	f2 fd                	repnz std
   f:	41 be d0 05 00 00    	mov    $0x5d0,%r14d
  15:	4c 03 33             	add    (%rbx),%r14
  18:	4c 89 f0             	mov    %r14,%rax
  1b:	48 c1 e8 03          	shr    $0x3,%rax
  1f:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  26:	fc ff df
* 29:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1) <-- trapping instruction
  2d:	74 08                	je     0x37
  2f:	4c 89 f7             	mov    %r14,%rdi
  32:	e8 77 f9 f2 fd       	call   0xfdf2f9ae
  37:	bb 90 00 00 00       	mov    $0x90,%ebx
  3c:	49 03 1e             	add    (%r14),%rbx