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: 5754 Comm: syz.2.272 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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 3f 1a 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 17 1a ec fd bb 90 00 00 00 49 03 1e RSP: 0018:ffffc9000456f700 EFLAGS: 00010202 RAX: 00000000000000ba RBX: ffff88805fa69648 RCX: dffffc0000000000 RDX: ffffc90005f79000 RSI: 000000000001c494 RDI: 000000000001c495 RBP: 1ffff1100bf4d2d1 R08: dffffc0000000000 R09: 1ffffffff203a818 R10: dffffc0000000000 R11: fffffbfff203a819 R12: ffff888029ec9110 R13: ffff88805fa69688 R14: 00000000000005d0 R15: ffff888027809dec FS: 00007f99fb10e6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000007ab1a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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 lmGCwrite fs/jfs/jfs_logmgr.c:-1 [inline] lmGroupCommit+0x5b4/0xb70 fs/jfs/jfs_logmgr.c:695 txCommit+0x4731/0x5200 fs/jfs/jfs_txnmgr.c:1305 jfs_commit_inode+0x2ec/0x520 fs/jfs/inode.c:114 jfs_fsync+0x181/0x1b0 fs/jfs/file.c:37 generic_write_sync include/linux/fs.h:2990 [inline] generic_file_write_iter+0x157/0x1b0 mm/filemap.c:3948 call_write_iter include/linux/fs.h:2173 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x745/0xd60 fs/read_write.c:594 ksys_write+0x152/0x260 fs/read_write.c:647 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: 0033:0x7f99fceb4819 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:00007f99fb10e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f99fd12dfa0 RCX: 00007f99fceb4819 RDX: 000000000000000a RSI: 0000200000000bc0 RDI: 000000000000000a RBP: 00007f99fcf4ac91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f99fd12e038 R14: 00007f99fd12dfa0 R15: 00007ffcd3598858 Modules linked in: ---[ end trace e2dcd81af892c10c ]--- 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 3f 1a 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 17 1a ec fd bb 90 00 00 00 49 03 1e RSP: 0018:ffffc9000456f700 EFLAGS: 00010202 RAX: 00000000000000ba RBX: ffff88805fa69648 RCX: dffffc0000000000 RDX: ffffc90005f79000 RSI: 000000000001c494 RDI: 000000000001c495 RBP: 1ffff1100bf4d2d1 R08: dffffc0000000000 R09: 1ffffffff203a818 R10: dffffc0000000000 R11: fffffbfff203a819 R12: ffff888029ec9110 R13: ffff88805fa69688 R14: 00000000000005d0 R15: ffff888027809dec FS: 00007f99fb10e6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000007ab1a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 80 3c 08 00 cmpb $0x0,(%rax,%rcx,1) 4: 74 08 je 0xe 6: 48 89 df mov %rbx,%rdi 9: e8 3f 1a ec fd call 0xfdec1a4d e: 41 be d0 05 00 00 mov $0x5d0,%r14d 14: 4c 03 33 add (%rbx),%r14 17: 4c 89 f0 mov %r14,%rax 1a: 48 c1 e8 03 shr $0x3,%rax 1e: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 25: fc ff df * 28: 80 3c 08 00 cmpb $0x0,(%rax,%rcx,1) <-- trapping instruction 2c: 74 08 je 0x36 2e: 4c 89 f7 mov %r14,%rdi 31: e8 17 1a ec fd call 0xfdec1a4d 36: bb 90 00 00 00 mov $0x90,%ebx 3b: 49 03 1e add (%r14),%rbx