[syzbot] [bcachefs?] kernel BUG in bch2_journal_keys_peek_max

[syzbot <syzbot+9b22c314d51cfbcd1ddc@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    69b54314c975 Merge tag 'kbuild-fixes-v6.14' of git://git.k..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=12213b18580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=147b7d49d83b8036
dashboard link: https://syzkaller.appspot.com/bug?extid=9b22c314d51cfbcd1ddc
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=1580c2a4580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17026bdf980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4c15b70890a6/disk-69b54314.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0db5658a86a2/vmlinux-69b54314.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f6a408104f8b/bzImage-69b54314.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/1c7e787a9111/mount_0.gz

The issue was bisected to:

commit 7e5b8e00e2631ee1fa72edeb420e7393ad078ab3
Author: Kent Overstreet <kent.overstreet@linux.dev>
Date:   Fri Oct 25 02:12:37 2024 +0000

    bcachefs: Implement bch2_btree_iter_prev_min()

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=11572b18580000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=13572b18580000
console output: https://syzkaller.appspot.com/x/log.txt?x=15572b18580000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9b22c314d51cfbcd1ddc@syzkaller.appspotmail.com
Fixes: 7e5b8e00e263 ("bcachefs: Implement bch2_btree_iter_prev_min()")

------------[ cut here ]------------
kernel BUG at fs/bcachefs/btree_journal_iter.c:83!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 5820 Comm: syz-executor138 Not tainted 6.14.0-rc1-syzkaller-00276-g69b54314c975 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:bch2_journal_keys_peek_max+0x164f/0x1660 fs/bcachefs/btree_journal_iter.c:83
Code: 10 48 8d 5c 08 18 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 ff b1 e1 fd 4c 8b 33 e9 d7 fe ff ff e8 12 a0 7d fd 90 <0f> 0b e8 2a 49 ac 07 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
RSP: 0018:ffffc90003fae620 EFLAGS: 00010293
RAX: ffffffff8441af2e RBX: 000000000000003b RCX: ffff88807f1c1e00
RDX: 0000000000000000 RSI: 000000000000003b RDI: ffffffffffffffff
RBP: ffffc90003fae7e0 R08: ffffffff84419a25 R09: 0000000000000000
R10: 00000001ffffffff R11: 2000000000000000 R12: dffffc0000000000
R13: ffff888074e00000 R14: ffffffffffffffff R15: ffffc90003faf018
FS:  000055558406b380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffdf737ed0 CR3: 0000000076148000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 bch2_btree_journal_peek fs/bcachefs/btree_iter.c:2137 [inline]
 btree_trans_peek_journal+0x342/0x5a0 fs/bcachefs/btree_iter.c:2166
 __bch2_btree_iter_peek fs/bcachefs/btree_iter.c:2303 [inline]
 bch2_btree_iter_peek_max+0x1502/0x6320 fs/bcachefs/btree_iter.c:2367
 bch2_btree_iter_peek_slot+0xe0a/0x27c0 fs/bcachefs/btree_iter.c:2820
 bch2_btree_iter_peek_prev_min+0x1f3/0x6390 fs/bcachefs/btree_iter.c:2606
 __bch2_resume_logged_op_finsert+0xd5c/0x3650 fs/bcachefs/io_misc.c:431
 bch2_fcollapse_finsert+0x257/0x380 fs/bcachefs/io_misc.c:535
 bchfs_fcollapse_finsert+0x3a8/0x630 fs/bcachefs/fs-io.c:594
 bch2_fallocate_dispatch+0x3c9/0x540
 vfs_fallocate+0x623/0x7a0 fs/open.c:338
 ksys_fallocate fs/open.c:362 [inline]
 __do_sys_fallocate fs/open.c:367 [inline]
 __se_sys_fallocate fs/open.c:365 [inline]
 __x64_sys_fallocate+0xbc/0x110 fs/open.c:365
 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: 0033:0x7ff945c437d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007fff0aa22888 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007fff0aa22890 RCX: 00007ff945c437d9
RDX: 0000000000000000 RSI: 0000000000000020 RDI: 0000000000000004
RBP: 0000400000000000 R08: 6c616b7a79732f2e R09: 6c616b7a79732f2e
R10: 0000000007000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fff0aa22a78 R14: 0000000000000001 R15: 0000000000000001
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:bch2_journal_keys_peek_max+0x164f/0x1660 fs/bcachefs/btree_journal_iter.c:83
Code: 10 48 8d 5c 08 18 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 ff b1 e1 fd 4c 8b 33 e9 d7 fe ff ff e8 12 a0 7d fd 90 <0f> 0b e8 2a 49 ac 07 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
RSP: 0018:ffffc90003fae620 EFLAGS: 00010293
RAX: ffffffff8441af2e RBX: 000000000000003b RCX: ffff88807f1c1e00
RDX: 0000000000000000 RSI: 000000000000003b RDI: ffffffffffffffff
RBP: ffffc90003fae7e0 R08: ffffffff84419a25 R09: 0000000000000000
R10: 00000001ffffffff R11: 2000000000000000 R12: dffffc0000000000
R13: ffff888074e00000 R14: ffffffffffffffff R15: ffffc90003faf018
FS:  000055558406b380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005572817bb0e8 CR3: 0000000076148000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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