[syzbot] [bcachefs?] kernel BUG in bch2_bkey_cmp_packed (2)

[syzbot <syzbot+00644eb66b865d7db7f0@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    90b83efa6701 Merge tag 'bpf-next-6.16' of git://git.kernel..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=122807f4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=262b2977ef00756b
dashboard link: https://syzkaller.appspot.com/bug?extid=00644eb66b865d7db7f0
compiler:       Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=162807f4580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12bedbf4580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-90b83efa.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/09e54f3c33aa/vmlinux-90b83efa.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6417d9c45508/bzImage-90b83efa.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/424513942ae2/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+00644eb66b865d7db7f0@syzkaller.appspotmail.com

    bi_nocow=0
    bi_depth=0
    bi_inodes_32bit=0
    bi_casefold=0
  nonzero k.p.inode, deleting
------------[ cut here ]------------
kernel BUG at fs/bcachefs/bkey_cmp.h:104!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5322 Comm: read_btree_node Not tainted 6.15.0-syzkaller-07774-g90b83efa6701 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__bch2_bkey_cmp_packed_format_checked_inlined fs/bcachefs/bkey_cmp.h:103 [inline]
RIP: 0010:bch2_bkey_cmp_packed_inlined fs/bcachefs/bkey_cmp.h:116 [inline]
RIP: 0010:bch2_bkey_cmp_packed+0x941/0x950 fs/bcachefs/bkey.c:1031
Code: fd 90 0f 0b e8 f0 67 a5 fd 90 0f 0b e8 e8 67 a5 fd 90 0f 0b e8 e0 67 a5 fd 90 0f 0b e8 d8 67 a5 fd 90 0f 0b e8 d0 67 a5 fd 90 <0f> 0b e8 c8 67 a5 fd 90 0f 0b 0f 1f 44 00 00 90 90 90 90 90 90 90
RSP: 0018:ffffc9000d46ebe0 EFLAGS: 00010293
RAX: ffffffff841a9320 RBX: dffffc0000000000 RCX: ffff88801c99c880
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00000000ffffffff
RBP: ffffc9000d46ed30 R08: ffffc9000d46ec3b R09: 0000000000000000
R10: ffffc9000d46ec30 R11: fffff52001a8dd88 R12: 00000000ffffffff
R13: 1ffff92001a8dd8c R14: 00000000ffffffff R15: 0000000800001000
FS:  0000000000000000(0000) GS:ffff88808d266000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe172b0da8 CR3: 0000000039110000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 btree_node_read_bkey_cmp fs/bcachefs/btree_io.c:935 [inline]
 validate_bset_keys+0xb9c/0x1390 fs/bcachefs/btree_io.c:1000
 bch2_btree_node_read_done+0x18c8/0x4f60 fs/bcachefs/btree_io.c:1211
 btree_node_read_work+0x426/0xe30 fs/bcachefs/btree_io.c:1400
 bch2_btree_node_read+0x887/0x29f0 fs/bcachefs/btree_io.c:-1
 bch2_btree_node_fill+0xd12/0x14f0 fs/bcachefs/btree_cache.c:994
 bch2_btree_node_get_noiter+0xa2c/0x1000 fs/bcachefs/btree_cache.c:1261
 found_btree_node_is_readable fs/bcachefs/btree_node_scan.c:85 [inline]
 try_read_btree_node fs/bcachefs/btree_node_scan.c:220 [inline]
 read_btree_nodes_worker+0x1319/0x1e20 fs/bcachefs/btree_node_scan.c:269
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__bch2_bkey_cmp_packed_format_checked_inlined fs/bcachefs/bkey_cmp.h:103 [inline]
RIP: 0010:bch2_bkey_cmp_packed_inlined fs/bcachefs/bkey_cmp.h:116 [inline]
RIP: 0010:bch2_bkey_cmp_packed+0x941/0x950 fs/bcachefs/bkey.c:1031
Code: fd 90 0f 0b e8 f0 67 a5 fd 90 0f 0b e8 e8 67 a5 fd 90 0f 0b e8 e0 67 a5 fd 90 0f 0b e8 d8 67 a5 fd 90 0f 0b e8 d0 67 a5 fd 90 <0f> 0b e8 c8 67 a5 fd 90 0f 0b 0f 1f 44 00 00 90 90 90 90 90 90 90
RSP: 0018:ffffc9000d46ebe0 EFLAGS: 00010293
RAX: ffffffff841a9320 RBX: dffffc0000000000 RCX: ffff88801c99c880
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00000000ffffffff
RBP: ffffc9000d46ed30 R08: ffffc9000d46ec3b R09: 0000000000000000
R10: ffffc9000d46ec30 R11: fffff52001a8dd88 R12: 00000000ffffffff
R13: 1ffff92001a8dd8c R14: 00000000ffffffff R15: 0000000800001000
FS:  0000000000000000(0000) GS:ffff88808d266000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe172b0da8 CR3: 0000000039110000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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