[syzbot] [reiserfs?] kernel BUG in balance_leaf

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 88603b6dc419 Linux 6.2-rc2
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=156f88b8480000
kernel config: https://syzkaller.appspot.com/x/.config?x=9babfdc3dd4772d0
dashboard link: https://syzkaller.appspot.com/bug?extid=6a0877ace12bfad107fc
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12bdb82a480000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=108acc94480000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a44a84e5e4e6/disk-88603b6d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/df723f71c09d/vmlinux-88603b6d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3db040a6ceef/bzImage-88603b6d.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/5c2f508ccf3c/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6a0877...@syzkaller.appspotmail.com

REISERFS (device loop0): Using r5 hash to sort names
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.
REISERFS panic (device loop0): vs-12195 balance_leaf: CFR not initialized
------------[ cut here ]------------
kernel BUG at fs/reiserfs/prints.c:390!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 5070 Comm: syz-executor245 Not tainted 6.2.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:__reiserfs_panic+0x12f/0x140 fs/reiserfs/prints.c:390
Code: c0 50 03 8b 48 0f 44 c8 48 0f 44 d8 48 c7 c7 80 51 03 8b 4c 89 fe 48 89 da 4d 89 f0 49 c7 c1 40 46 16 92 31 c0 e8 01 ec 82 08 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41
RSP: 0018:ffffc90003d5e7e0 EFLAGS: 00010246
RAX: 0000000000000049 RBX: ffffffff8b02e520 RCX: 37780e38b943e200
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc90003d5e8d0 R08: ffffffff816f2c9d R09: fffff520007abcb5
R10: fffff520007abcb5 R11: 1ffff920007abcb4 R12: ffffffff8b02e540
R13: ffffc90003d5e800 R14: ffffffff8cc70ec0 R15: ffff888028b806a8
FS: 00007fd74c6aa700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd744689718 CR3: 0000000079f45000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
balance_leaf+0x109eb/0x123a0 fs/reiserfs/do_balan.c:1439
do_balance+0x2d6/0x8d0 fs/reiserfs/do_balan.c:1888
reiserfs_insert_item+0xb54/0xcb0 fs/reiserfs/stree.c:2261
reiserfs_new_inode+0x11c7/0x1cd0 fs/reiserfs/inode.c:2054
reiserfs_create+0x3a6/0x660 fs/reiserfs/namei.c:668
lookup_open fs/namei.c:3413 [inline]
open_last_lookups fs/namei.c:3481 [inline]
path_openat+0x12ac/0x2dd0 fs/namei.c:3711
do_filp_open+0x264/0x4f0 fs/namei.c:3741
do_sys_openat2+0x124/0x4e0 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_openat fs/open.c:1342 [inline]
__se_sys_openat fs/open.c:1337 [inline]
__x64_sys_openat+0x243/0x290 fs/open.c:1337
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fd74c6fe559
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 71 15 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:00007fd74c6aa2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fd74c7847a0 RCX: 00007fd74c6fe559
RDX: 0000000000000241 RSI: 0000000020000000 RDI: 00000000ffffff9c
RBP: 00007fd74c7512b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd74c7511b8
R13: 0030656c69662f2e R14: 7366726573696572 R15: 00007fd74c7847a8
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__reiserfs_panic+0x12f/0x140 fs/reiserfs/prints.c:390
Code: c0 50 03 8b 48 0f 44 c8 48 0f 44 d8 48 c7 c7 80 51 03 8b 4c 89 fe 48 89 da 4d 89 f0 49 c7 c1 40 46 16 92 31 c0 e8 01 ec 82 08 <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41
RSP: 0018:ffffc90003d5e7e0 EFLAGS: 00010246
RAX: 0000000000000049 RBX: ffffffff8b02e520 RCX: 37780e38b943e200
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc90003d5e8d0 R08: ffffffff816f2c9d R09: fffff520007abcb5
R10: fffff520007abcb5 R11: 1ffff920007abcb4 R12: ffffffff8b02e540
R13: ffffc90003d5e800 R14: ffffffff8cc70ec0 R15: ffff888028b806a8
FS: 00007fd74c6aa700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd744689718 CR3: 0000000079f45000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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[syzbot]

syzbot suspects this issue was fixed by commit:

commit 6f861765464f43a71462d52026fbddfc858239a5
Author: Jan Kara <ja...@suse.cz>
Date: Wed Nov 1 17:43:10 2023 +0000

fs: Block writes to mounted block devices

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10cc8ee7e80000
start commit: 88603b6dc419 Linux 6.2-rc2
git tree: upstream

kernel config: https://syzkaller.appspot.com/x/.config?x=9babfdc3dd4772d0
dashboard link: https://syzkaller.appspot.com/bug?extid=6a0877ace12bfad107fc

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12bdb82a480000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=108acc94480000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: fs: Block writes to mounted block devices

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

[Jan Kara]

On Sat 20-01-24 19:17:02, syzbot wrote:
> syzbot suspects this issue was fixed by commit:
>
> commit 6f861765464f43a71462d52026fbddfc858239a5
> Author: Jan Kara <ja...@suse.cz>
> Date: Wed Nov 1 17:43:10 2023 +0000
>
> fs: Block writes to mounted block devices
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10cc8ee7e80000
> start commit: 88603b6dc419 Linux 6.2-rc2
> git tree: upstream
> kernel config: https://syzkaller.appspot.com/x/.config?x=9babfdc3dd4772d0
> dashboard link: https://syzkaller.appspot.com/bug?extid=6a0877ace12bfad107fc
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12bdb82a480000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=108acc94480000
>
> If the result looks correct, please mark the issue as fixed by replying with:

Makes sense:

#syz fix: fs: Block writes to mounted block devices

Honza
--
Jan Kara <ja...@suse.com>
SUSE Labs, CR