general protection fault, probably for non-canonical address 0xdffffc0000000097: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000004b8-0x00000000000004bf] CPU: 1 PID: 264 Comm: kworker/1:1H Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: glock_workqueue glock_work_func RIP: 0010:is_system_glock fs/gfs2/glock.c:693 [inline] RIP: 0010:do_xmote+0xd15/0x10a0 fs/gfs2/glock.c:801 Code: ff df 80 3c 08 00 74 08 4c 89 f7 e8 a5 c9 4c fe 41 bf b8 04 00 00 4d 03 3e 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ff e8 7d c9 4c fe 49 3b 1f 74 39 48 8d 7b RSP: 0018:ffffc90002037b88 EFLAGS: 00010202 RAX: 0000000000000097 RBX: ffff88807a2c8548 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000004000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffff88807bce00af R09: 1ffff1100f79c015 R10: dffffc0000000000 R11: ffffed100f79c016 R12: dffffc0000000000 R13: ffff88807a2c8568 R14: ffff88807bce0718 R15: 00000000000004b8 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2aa692 CR3: 000000007da1a000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: glock_work_func+0x25c/0x470 fs/gfs2/glock.c:1039 process_one_work+0x867/0xff0 kernel/workqueue.c:2310 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457 kthread+0x42e/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Modules linked in: ---[ end trace 51cb0c29ec873168 ]--- RIP: 0010:is_system_glock fs/gfs2/glock.c:693 [inline] RIP: 0010:do_xmote+0xd15/0x10a0 fs/gfs2/glock.c:801 Code: ff df 80 3c 08 00 74 08 4c 89 f7 e8 a5 c9 4c fe 41 bf b8 04 00 00 4d 03 3e 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 4c 89 ff e8 7d c9 4c fe 49 3b 1f 74 39 48 8d 7b RSP: 0018:ffffc90002037b88 EFLAGS: 00010202 RAX: 0000000000000097 RBX: ffff88807a2c8548 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000004000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffff88807bce00af R09: 1ffff1100f79c015 R10: dffffc0000000000 R11: ffffed100f79c016 R12: dffffc0000000000 R13: ffff88807a2c8568 R14: ffff88807bce0718 R15: 00000000000004b8 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000002f3030 CR3: 000000005f184000 CR4: 00000000003506e0 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 4c 89 f7 or %cl,-0x9(%rcx,%rcx,4) b: e8 a5 c9 4c fe call 0xfe4cc9b5 10: 41 bf b8 04 00 00 mov $0x4b8,%r15d 16: 4d 03 3e add (%r14),%r15 19: 4c 89 f8 mov %r15,%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 ff mov %r15,%rdi 33: e8 7d c9 4c fe call 0xfe4cc9b5 38: 49 3b 1f cmp (%r15),%rbx 3b: 74 39 je 0x76 3d: 48 rex.W 3e: 8d .byte 0x8d 3f: 7b .byte 0x7b