[syzbot] [bcachefs?] kernel BUG in bch2_get_scanned_nodes

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    f486c8aa16b8 Add linux-next specific files for 20241128
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1432a3c0580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e348a4873516af92
dashboard link: https://syzkaller.appspot.com/bug?extid=64e6509c7f777aec3a24
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1389ef5f980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=164a8f78580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/beb58ebb63cf/disk-f486c8aa.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b241b5609e64/vmlinux-f486c8aa.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c9d817f665f2/bzImage-f486c8aa.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/ee49d5c23880/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+64e6509c7f777aec3a24@xxxxxxxxxxxxxxxxxxxxxxxxx

bcachefs (loop0): bch2_get_scanned_nodes(): recovery btree=xattrs level=0 POS_MIN - SPOS_MAX
bcachefs (loop0): bch2_get_scanned_nodes(): recovering u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 22000000ba0abe32 written 8 min_key POS_MIN durability: 1 ptr: 0:31:0 gen 0
invalid bkey in btree_node btree=xattrs level=0: u64s 11 type btree_ptr_v2 SPOS_MAX len 0 ver 0: seq 22000000ba0abe32 written 8 min_key POS_MIN durability: 1 ptr: 0:31:0 gen 0
  key at POS_MAX: delete?, fixing
------------[ cut here ]------------
kernel BUG at fs/bcachefs/btree_node_scan.c:546!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 5831 Comm: syz-executor341 Not tainted 6.12.0-next-20241128-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:bch2_get_scanned_nodes+0x1e23/0x1e30 fs/bcachefs/btree_node_scan.c:541
Code: 24 18 48 8d b4 24 f0 03 00 00 48 8b 94 24 00 01 00 00 e9 17 e8 ff ff e8 4b de a7 07 e8 f6 74 73 fd 90 0f 0b e8 ee 74 73 fd 90 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90003e36cc0 EFLAGS: 00010293
RAX: ffffffff842c0012 RBX: ffff888074b80000 RCX: ffff888035983c00
RDX: 0000000000000000 RSI: 00000000fffff75b RDI: 0000000000000000
RBP: ffffc90003e37160 R08: ffffffff842bf611 R09: 1ffffffff285892b
R10: dffffc0000000000 R11: fffffbfff285892c R12: 1ffff920007c6dcc
R13: ffffc90003e37020 R14: 00000000fffff75b R15: dffffc0000000000
FS:  0000555584e7a380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005590e5ed3c28 CR3: 0000000074aca000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 bch2_check_topology+0x597/0xbb0 fs/bcachefs/btree_gc.c:543
 bch2_run_recovery_pass+0xf0/0x1e0 fs/bcachefs/recovery_passes.c:222
 bch2_run_recovery_passes+0x290/0x9f0 fs/bcachefs/recovery_passes.c:285
 bch2_fs_recovery+0x2660/0x3ab0 fs/bcachefs/recovery.c:917
 bch2_fs_start+0x37c/0x610 fs/bcachefs/super.c:1037
 bch2_fs_get_tree+0xd8d/0x1740 fs/bcachefs/fs.c:2201
 vfs_get_tree+0x90/0x2b0 fs/super.c:1814
 do_new_mount+0x2be/0xb40 fs/namespace.c:3507
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4057 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8b2490497a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 5e 04 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffe3bd4ff8 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fffe3bd5010 RCX: 00007f8b2490497a
RDX: 00000000200000c0 RSI: 0000000020000040 RDI: 00007fffe3bd5010
RBP: 0000000000000004 R08: 00007fffe3bd5050 R09: 000000000000595a
R10: 0000000000800000 R11: 0000000000000282 R12: 0000000000800000
R13: 00007fffe3bd5050 R14: 0000000000000003 R15: 0000000001000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:bch2_get_scanned_nodes+0x1e23/0x1e30 fs/bcachefs/btree_node_scan.c:541
Code: 24 18 48 8d b4 24 f0 03 00 00 48 8b 94 24 00 01 00 00 e9 17 e8 ff ff e8 4b de a7 07 e8 f6 74 73 fd 90 0f 0b e8 ee 74 73 fd 90 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90003e36cc0 EFLAGS: 00010293
RAX: ffffffff842c0012 RBX: ffff888074b80000 RCX: ffff888035983c00
RDX: 0000000000000000 RSI: 00000000fffff75b RDI: 0000000000000000
RBP: ffffc90003e37160 R08: ffffffff842bf611 R09: 1ffffffff285892b
R10: dffffc0000000000 R11: fffffbfff285892c R12: 1ffff920007c6dcc
R13: ffffc90003e37020 R14: 00000000fffff75b R15: dffffc0000000000
FS:  0000555584e7a380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005590e5ed3c28 CR3: 0000000074aca000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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