[syzbot] [jfs?] UBSAN: array-index-out-of-bounds in dbAdjTree (2)

syzbot
2024-05-18T12:29:33Z

Hello,

syzbot found the following issue on:

HEAD commit: ea5f6ad9ad96 Merge tag 'platform-drivers-x86-v6.10-1' of g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10e91bd4980000
kernel config: https://syzkaller.appspot.com/x/.config?x=3e06a6259c6a4416
dashboard link: https://syzkaller.appspot.com/bug?extid=412dea214d8baa3f7483
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/db5d9201b572/disk-ea5f6ad9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8d8ed484f1b5/vmlinux-ea5f6ad9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0de047f553aa/bzImage-ea5f6ad9.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+412dea214d8baa3f7483@syzkaller.appspotmail.com

UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:2900:31
index -3 is out of range for type 's8 [1365]'
CPU: 0 PID: 111 Comm: jfsCommit Not tainted 6.9.0-syzkaller-08284-gea5f6ad9ad96 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:114
ubsan_epilogue lib/ubsan.c:231 [inline]
__ubsan_handle_out_of_bounds+0x110/0x150 lib/ubsan.c:429
dbAdjTree+0x383/0x3d0 fs/jfs/jfs_dmap.c:2900
dbJoin+0x24b/0x2b0 fs/jfs/jfs_dmap.c:2841
dbFreeBits+0x15c/0x8f0 fs/jfs/jfs_dmap.c:2338
dbFreeDmap+0x62/0x1b0 fs/jfs/jfs_dmap.c:2087
dbFree+0x266/0x550 fs/jfs/jfs_dmap.c:409
txFreeMap+0x788/0xe60 fs/jfs/jfs_txnmgr.c:2515
xtTruncate+0x1e57/0x2c80 fs/jfs/jfs_xtree.c:2467
jfs_free_zero_link+0x372/0x4f0 fs/jfs/namei.c:759
jfs_evict_inode+0x423/0x4b0 fs/jfs/inode.c:153
evict+0x2f0/0x6c0 fs/inode.c:667
iput_final fs/inode.c:1741 [inline]
iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
iput+0x5c/0x80 fs/inode.c:1757
txUpdateMap+0xaf3/0xd20 fs/jfs/jfs_txnmgr.c:2367
txLazyCommit fs/jfs/jfs_txnmgr.c:2664 [inline]
jfs_lazycommit+0x5e6/0xb20 fs/jfs/jfs_txnmgr.c:2733
kthread+0x2c4/0x3a0 kernel/kthread.c:389
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
---[ end trace ]---

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