Re: [syzbot] [jfs?] kernel BUG in txUnlock

From: syzbot
Date: Sat Dec 24 2022 - 00:58:40 EST


syzbot has found a reproducer for the following issue on:

HEAD commit: a5541c0811a0 Merge branch 'for-next/core' into for-kernelci
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=11fbab64480000
kernel config: https://syzkaller.appspot.com/x/.config?x=cbd4e584773e9397
dashboard link: https://syzkaller.appspot.com/bug?extid=a63afa301d1258d09267
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1779a650480000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16346274480000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4b7702208fb9/disk-a5541c08.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9ec0153ec051/vmlinux-a5541c08.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6f8725ad290a/Image-a5541c08.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/4aaac3b4e5ee/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a63afa301d1258d09267@xxxxxxxxxxxxxxxxxxxxxxxxx

BUG at fs/jfs/jfs_txnmgr.c:926 assert(mp->nohomeok > 0)
------------[ cut here ]------------
kernel BUG at fs/jfs/jfs_txnmgr.c:926!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 90 Comm: jfsCommit Not tainted 6.1.0-rc8-syzkaller-33330-ga5541c0811a0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : txUnlock+0x6f4/0x738 fs/jfs/jfs_txnmgr.c:926
lr : txUnlock+0x6f4/0x738 fs/jfs/jfs_txnmgr.c:926
sp : ffff80000fe93d30
x29: ffff80000fe93d70 x28: ffff800012902000 x27: 0000000000000002
x26: ffff80000efd4308 x25: ffff80000efd4000 x24: ffff0000cd24d000
x23: ffff80000efd4000 x22: 0000000000000048 x21: ffff80000efd42b4
x20: ffff80000efd4000 x19: 0000000000000000 x18: 00000000000000c0
x17: ffff80000dda8198 x16: ffff80000dbe6158 x15: ffff0000c0fd1a40
x14: 0000000000000000 x13: 00000000ffffffff x12: ffff0000c0fd1a40
x11: ff808000081c4d64 x10: 0000000000000000 x9 : 1da0f0d83d883600
x8 : 1da0f0d83d883600 x7 : ffff80000c091ebc x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : ffff0001fefddcd0 x1 : 0000000100000000 x0 : 0000000000000037
Call trace:
txUnlock+0x6f4/0x738 fs/jfs/jfs_txnmgr.c:926
txLazyCommit fs/jfs/jfs_txnmgr.c:2677 [inline]
jfs_lazycommit+0x228/0x4b8 fs/jfs/jfs_txnmgr.c:2727
kthread+0x12c/0x158 kernel/kthread.c:376
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:863
Code: 910d7021 91288c63 528073c2 94cbec2c (d4210000)
---[ end trace 0000000000000000 ]---