Oops: general protection fault, probably for non-canonical address 0xdffffc0000000011: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000088-0x000000000000008f] CPU: 1 UID: 0 PID: 42 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT(none) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events gfs2_withdraw_func RIP: 0010:gfs2_log_is_empty+0x73/0xd0 fs/gfs2/log.c:430 Code: e0 09 00 00 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 0d 9d 34 ff 41 be 8c 00 00 00 4c 03 33 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 38 84 c0 75 34 41 8b 1e 89 ef 89 de e8 98 03 f1 fe 39 RSP: 0018:ffffc900002c7938 EFLAGS: 00010207 RAX: 0000000000000011 RBX: ffff888113ce09e0 RCX: ffffffff82ae3380 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff888113ce0d60 RBP: 0000000000001000 R08: ffff888113ce0d63 R09: 1ffff1102279c1ac R10: dffffc0000000000 R11: ffffed102279c1ad R12: ffff8881f5937780 R13: ffff888113ce0000 R14: 000000000000008c R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8882695cd000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd46e3d1000 CR3: 000000017d288000 CR4: 00000000003506f0 Call Trace: do_withdraw fs/gfs2/util.c:139 [inline] gfs2_withdraw_func+0x283/0x4f0 fs/gfs2/util.c:185 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:gfs2_log_is_empty+0x73/0xd0 fs/gfs2/log.c:430 Code: e0 09 00 00 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 0d 9d 34 ff 41 be 8c 00 00 00 4c 03 33 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 38 84 c0 75 34 41 8b 1e 89 ef 89 de e8 98 03 f1 fe 39 RSP: 0018:ffffc900002c7938 EFLAGS: 00010207 RAX: 0000000000000011 RBX: ffff888113ce09e0 RCX: ffffffff82ae3380 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff888113ce0d60 RBP: 0000000000001000 R08: ffff888113ce0d63 R09: 1ffff1102279c1ac R10: dffffc0000000000 R11: ffffed102279c1ad R12: ffff8881f5937780 R13: ffff888113ce0000 R14: 000000000000008c R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8882695cd000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd46e3d1000 CR3: 000000017d288000 CR4: 00000000003506f0 ---------------- Code disassembly (best guess): 0: e0 09 loopne 0xb 2: 00 00 add %al,(%rax) 4: 48 89 d8 mov %rbx,%rax 7: 48 c1 e8 03 shr $0x3,%rax b: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) 10: 74 08 je 0x1a 12: 48 89 df mov %rbx,%rdi 15: e8 0d 9d 34 ff call 0xff349d27 1a: 41 be 8c 00 00 00 mov $0x8c,%r14d 20: 4c 03 33 add (%rbx),%r14 23: 4c 89 f0 mov %r14,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 0f b6 04 38 movzbl (%rax,%r15,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 75 34 jne 0x67 33: 41 8b 1e mov (%r14),%ebx 36: 89 ef mov %ebp,%edi 38: 89 de mov %ebx,%esi 3a: e8 98 03 f1 fe call 0xfef103d7 3f: 39 .byte 0x39