[syzbot] [ocfs2?] kernel BUG in ocfs2_write_block

syzbot
2024-09-19T00:02:23Z

Hello,

syzbot found the following issue on:

HEAD commit: d42f7708e27c Merge tag 'for-linus-6.11' of git://git.kerne..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=16d197c7980000
kernel config: https://syzkaller.appspot.com/x/.config?x=1c9e296880039df9
dashboard link: https://syzkaller.appspot.com/bug?extid=c818e5c4559444f88aa0
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=17c3e407980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12bb9900580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b879ea3b7dd4/disk-d42f7708.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/812a7fb7bfcc/vmlinux-d42f7708.xz
kernel image: https://storage.googleapis.com/syzbot-assets/806a22d4adbf/bzImage-d42f7708.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/e983237a6366/mount_0.gz

Bisection is inconclusive: the issue happens on the oldest tested release.

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=16fa229f980000
final oops: https://syzkaller.appspot.com/x/report.txt?x=15fa229f980000
console output: https://syzkaller.appspot.com/x/log.txt?x=11fa229f980000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c818e5c4559444f88aa0@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 32768
=======================================================
WARNING: The mand mount option has been deprecated and
and is ignored by this kernel. Remove the mand
option from the mount to silence this warning.
=======================================================
------------[ cut here ]------------
kernel BUG at fs/ocfs2/buffer_head_io.c:45!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 5224 Comm: syz-executor227 Not tainted 6.11.0-rc7-syzkaller-00151-gd42f7708e27c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:ocfs2_write_block+0x62a/0x6b0 fs/ocfs2/buffer_head_io.c:45
Code: fc ff df 80 3c 08 00 74 08 4c 89 ef e8 5f 41 7a fe 49 8b 7d 00 48 89 de 48 8b 54 24 08 e8 de 44 11 00 eb 2e e8 97 1d 16 fe 90 <0f> 0b e8 8f 1d 16 fe 90 0f 0b e8 97 aa 33 08 e8 82 1d 16 fe 49 bd
RSP: 0018:ffffc90003326dc0 EFLAGS: 00010293
RAX: ffffffff837d6ec9 RBX: 0000000000000000 RCX: ffff88801b318000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc90003326e90 R08: ffffffff837d6a20 R09: 1ffffffff1fee945
R10: dffffc0000000000 R11: fffffbfff1fee946 R12: ffff88807e9ef2d0
R13: dffffc0000000000 R14: ffff88807e9ef2b8 R15: ffff888011958000
FS: 0000555580ce5380(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fae84395ed8 CR3: 0000000078dfe000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ocfs2_update_disk_slot+0x498/0x690 fs/ocfs2/slot_map.c:197
ocfs2_find_slot+0x4cb/0xaa0 fs/ocfs2/slot_map.c:482
ocfs2_mount_volume+0x1a0/0x1940 fs/ocfs2/super.c:1806
ocfs2_fill_super+0x483b/0x5880 fs/ocfs2/super.c:1084
mount_bdev+0x20a/0x2d0 fs/super.c:1679
legacy_get_tree+0xee/0x190 fs/fs_context.c:662
vfs_get_tree+0x90/0x2b0 fs/super.c:1800
do_new_mount+0x2be/0xb40 fs/namespace.c:3472
do_mount fs/namespace.c:3812 [inline]
__do_sys_mount fs/namespace.c:4020 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3997
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: 0033:0x7f2a220a1dea
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:00007ffc219a6e28 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffc219a6e40 RCX: 00007f2a220a1dea
RDX: 0000000020000280 RSI: 0000000020000040 RDI: 00007ffc219a6e40
RBP: 0000000000000004 R08: 00007ffc219a6e80 R09: 0000000000004440
R10: 00000000000008c0 R11: 0000000000000282 R12: 00000000000008c0
R13: 00007ffc219a6e80 R14: 0000000000000003 R15: 0000000001000000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ocfs2_write_block+0x62a/0x6b0 fs/ocfs2/buffer_head_io.c:45
Code: fc ff df 80 3c 08 00 74 08 4c 89 ef e8 5f 41 7a fe 49 8b 7d 00 48 89 de 48 8b 54 24 08 e8 de 44 11 00 eb 2e e8 97 1d 16 fe 90 <0f> 0b e8 8f 1d 16 fe 90 0f 0b e8 97 aa 33 08 e8 82 1d 16 fe 49 bd
RSP: 0018:ffffc90003326dc0 EFLAGS: 00010293
RAX: ffffffff837d6ec9 RBX: 0000000000000000 RCX: ffff88801b318000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffc90003326e90 R08: ffffffff837d6a20 R09: 1ffffffff1fee945
R10: dffffc0000000000 R11: fffffbfff1fee946 R12: ffff88807e9ef2d0
R13: dffffc0000000000 R14: ffff88807e9ef2b8 R15: ffff888011958000
FS: 0000555580ce5380(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560086f89778 CR3: 0000000078dfe000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

---
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