BTRFS info (device loop3): qgroup scan completed (inconsistency flag cleared) general protection fault, probably for non-canonical address 0xdffffc0000000041: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000208-0x000000000000020f] CPU: 0 PID: 33 Comm: kworker/u4:2 Not tainted 6.2.0-rc2-syzkaller-00010-g69b41ac87e4a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Workqueue: btrfs-qgroup-rescan btrfs_work_helper RIP: 0010:start_transaction+0x48/0x10f0 fs/btrfs/transaction.c:564 Code: 48 89 fb 48 bd 00 00 00 00 00 fc ff df e8 b0 72 00 fe 48 89 5c 24 38 48 81 c3 08 02 00 00 48 89 d8 48 c1 e8 03 48 89 44 24 70 <80> 3c 28 00 74 08 48 89 df e8 7a 1c 56 fe 48 89 5c 24 60 48 8b 03 RSP: 0018:ffffc90000aa7ab0 EFLAGS: 00010206 RAX: 0000000000000041 RBX: 0000000000000208 RCX: ffff888012a98000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: dffffc0000000000 R08: 0000000000000001 R09: fffff52000154f5d R10: fffff52000154f5d R11: 1ffff92000154f5c R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000003 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc4b7306e68 CR3: 000000007c876000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: btrfs_qgroup_rescan_worker+0x3bb/0x6a0 fs/btrfs/qgroup.c:3403 btrfs_work_helper+0x312/0x850 fs/btrfs/async-thread.c:280 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:start_transaction+0x48/0x10f0 fs/btrfs/transaction.c:564 Code: 48 89 fb 48 bd 00 00 00 00 00 fc ff df e8 b0 72 00 fe 48 89 5c 24 38 48 81 c3 08 02 00 00 48 89 d8 48 c1 e8 03 48 89 44 24 70 <80> 3c 28 00 74 08 48 89 df e8 7a 1c 56 fe 48 89 5c 24 60 48 8b 03 RSP: 0018:ffffc90000aa7ab0 EFLAGS: 00010206 RAX: 0000000000000041 RBX: 0000000000000208 RCX: ffff888012a98000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: dffffc0000000000 R08: 0000000000000001 R09: fffff52000154f5d R10: fffff52000154f5d R11: 1ffff92000154f5c R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000003 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffdbdc81068 CR3: 000000007e8b3000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 48 89 fb mov %rdi,%rbx 3: 48 bd 00 00 00 00 00 movabs $0xdffffc0000000000,%rbp a: fc ff df d: e8 b0 72 00 fe callq 0xfe0072c2 12: 48 89 5c 24 38 mov %rbx,0x38(%rsp) 17: 48 81 c3 08 02 00 00 add $0x208,%rbx 1e: 48 89 d8 mov %rbx,%rax 21: 48 c1 e8 03 shr $0x3,%rax 25: 48 89 44 24 70 mov %rax,0x70(%rsp) * 2a: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1) <-- trapping instruction 2e: 74 08 je 0x38 30: 48 89 df mov %rbx,%rdi 33: e8 7a 1c 56 fe callq 0xfe561cb2 38: 48 89 5c 24 60 mov %rbx,0x60(%rsp) 3d: 48 8b 03 mov (%rbx),%rax