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: 4468 Comm: kworker/u4:9 Not tainted 5.15.185-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: writeback wb_workfn (flush-7:2) 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 72 59 f3 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 4a 59 f3 fd 41 bf 90 00 00 00 4d 03 RSP: 0018:ffffc9000132f260 EFLAGS: 00010202 RAX: 00000000000000ba RBX: ffff88807d8b7008 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffffffff96249f60 RDI: ffff88807d8b7000 RBP: 1ffff1100fb16e09 R08: dffffc0000000000 R09: fffffbfff1ff3619 R10: fffffbfff1ff3619 R11: 1ffffffff1ff3618 R12: 1ffff1100fb16e01 R13: ffff88807d8b7048 R14: 00000000000005d0 R15: ffff8880218f596c FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbdd0fe4000 CR3: 0000000022f52000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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 Modules linked in: ---[ end trace fe7a12ad0ba350b4 ]--- 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 72 59 f3 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 4a 59 f3 fd 41 bf 90 00 00 00 4d 03 RSP: 0018:ffffc9000132f260 EFLAGS: 00010202 RAX: 00000000000000ba RBX: ffff88807d8b7008 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffffffff96249f60 RDI: ffff88807d8b7000 RBP: 1ffff1100fb16e09 R08: dffffc0000000000 R09: fffffbfff1ff3619 R10: fffffbfff1ff3619 R11: 1ffffffff1ff3618 R12: 1ffff1100fb16e01 R13: ffff88807d8b7048 R14: 00000000000005d0 R15: ffff8880218f596c FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd2eaa90d58 CR3: 000000007a78e000 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 72 59 f3 fd call 0xfdf35982 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 4a 59 f3 fd call 0xfdf35982 38: 41 bf 90 00 00 00 mov $0x90,%r15d 3e: 4d rex.WRB 3f: 03 .byte 0x3