linux-kernel - [syzbot] [bcachefs?] kernel BUG in bch2_btree_pos_to

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Message-ID: <66ef45f0.050a0220.3195df.006d.GAE@google.com>
Date: Sat, 21 Sep 2024 15:17:20 -0700
From: syzbot <syzbot+cf7b2215b5d70600ec00@...kaller.appspotmail.com>
To: kent.overstreet@...ux.dev, linux-bcachefs@...r.kernel.org, 
	linux-kernel@...r.kernel.org, syzkaller-bugs@...glegroups.com
Subject: [syzbot] [bcachefs?] kernel BUG in bch2_btree_pos_to_text

Hello,

syzbot found the following issue on:

HEAD commit:    a940d9a43e62 Merge tag 'soc-arm-6.12' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15ac44a9980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1653f803fffa3848
dashboard link: https://syzkaller.appspot.com/bug?extid=cf7b2215b5d70600ec00
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=1276469f980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17731207980000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-a940d9a4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/371e11b6a9e5/vmlinux-a940d9a4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/920eb0c53785/bzImage-a940d9a4.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/613a2d63144c/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+cf7b2215b5d70600ec00@...kaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at fs/bcachefs/btree_cache.h:126!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5111 Comm: read_btree_node Not tainted 6.11.0-syzkaller-03917-ga940d9a43e62 #0
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_btree_id_root fs/bcachefs/btree_cache.h:126 [inline]
RIP: 0010:bch2_btree_pos_to_text+0x1ee/0x1f0 fs/bcachefs/btree_cache.c:1295
Code: 00 00 fc ff df e9 70 ff ff ff 89 d9 80 e1 07 38 c1 0f 8c 7a ff ff ff 48 89 df e8 2d 90 ec fd e9 6d ff ff ff e8 b3 4b 85 fd 90 <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa
RSP: 0018:ffffc9000315f448 EFLAGS: 00010293
RAX: ffffffff840ede8d RBX: 00000000000000de RCX: ffff88801e138000
RDX: 0000000000000000 RSI: 00000000000000de RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff840edd7a R09: 0000000000000000
R10: ffffc9000315f5e0 R11: fffff5200062bec1 R12: ffff8880410b0000
R13: ffff888041280000 R14: ffff888041280000 R15: ffffc9000315f5e0
FS:  0000000000000000(0000) GS:ffff88801fe00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559507bd4640 CR3: 000000003f78a000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 btree_node_read_work+0x486/0x1260 fs/bcachefs/btree_io.c:1308
 bch2_btree_node_read+0x2433/0x2a10
 bch2_btree_node_fill+0xcd1/0x1320 fs/bcachefs/btree_cache.c:886
 bch2_btree_node_get_noiter+0x9b3/0xf50 fs/bcachefs/btree_cache.c:1155
 found_btree_node_is_readable fs/bcachefs/btree_node_scan.c:85 [inline]
 try_read_btree_node fs/bcachefs/btree_node_scan.c:190 [inline]
 read_btree_nodes_worker+0x122c/0x20b0 fs/bcachefs/btree_node_scan.c:239
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:bch2_btree_id_root fs/bcachefs/btree_cache.h:126 [inline]
RIP: 0010:bch2_btree_pos_to_text+0x1ee/0x1f0 fs/bcachefs/btree_cache.c:1295
Code: 00 00 fc ff df e9 70 ff ff ff 89 d9 80 e1 07 38 c1 0f 8c 7a ff ff ff 48 89 df e8 2d 90 ec fd e9 6d ff ff ff e8 b3 4b 85 fd 90 <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa
RSP: 0018:ffffc9000315f448 EFLAGS: 00010293
RAX: ffffffff840ede8d RBX: 00000000000000de RCX: ffff88801e138000
RDX: 0000000000000000 RSI: 00000000000000de RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff840edd7a R09: 0000000000000000
R10: ffffc9000315f5e0 R11: fffff5200062bec1 R12: ffff8880410b0000
R13: ffff888041280000 R14: ffff888041280000 R15: ffffc9000315f5e0
FS:  0000000000000000(0000) GS:ffff88801fe00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000559507bd4640 CR3: 0000000011a04000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
This report is generated by a bot. It may contain errors.
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