[syzbot] [jfs?] UBSAN: array-index-out-of-bounds in diFree

syzbot
2024-04-23T22:25:29Z

Hello,

syzbot found the following issue on:

HEAD commit: 3cdb45594619 Merge tag 's390-6.9-4' of git://git.kernel.or..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=115a2547180000
kernel config: https://syzkaller.appspot.com/x/.config?x=f47e5e015c177e57
dashboard link: https://syzkaller.appspot.com/bug?extid=241c815bda521982cb49
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=109bb8f7180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17e54bab180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4befd8e98bed/disk-3cdb4559.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/efc09f95602f/vmlinux-3cdb4559.xz
kernel image: https://storage.googleapis.com/syzbot-assets/29a54be03694/bzImage-3cdb4559.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/784deb2bb8a2/mount_0.gz

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

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14dc8b53180000
final oops: https://syzkaller.appspot.com/x/report.txt?x=16dc8b53180000
console output: https://syzkaller.appspot.com/x/log.txt?x=12dc8b53180000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+241c815bda521982cb49@syzkaller.appspotmail.com

------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_imap.c:886:2
index 524288 is out of range for type 'struct mutex[128]'
CPU: 1 PID: 111 Comm: jfsCommit Not tainted 6.9.0-rc4-syzkaller-00173-g3cdb45594619 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
ubsan_epilogue lib/ubsan.c:217 [inline]
__ubsan_handle_out_of_bounds+0x121/0x150 lib/ubsan.c:415
diFree+0x21c3/0x2fb0 fs/jfs/jfs_imap.c:886
jfs_evict_inode+0x32d/0x440 fs/jfs/inode.c:156
evict+0x2a8/0x630 fs/inode.c:667
txUpdateMap+0x829/0x9f0 fs/jfs/jfs_txnmgr.c:2367
txLazyCommit fs/jfs/jfs_txnmgr.c:2664 [inline]
jfs_lazycommit+0x49a/0xb80 fs/jfs/jfs_txnmgr.c:2733
kthread+0x2f0/0x390 kernel/kthread.c:388
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>
---[ end trace ]---
Kernel panic - not syncing: UBSAN: panic_on_warn set ...
CPU: 1 PID: 111 Comm: jfsCommit Not tainted 6.9.0-rc4-syzkaller-00173-g3cdb45594619 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
panic+0x349/0x860 kernel/panic.c:348
check_panic_on_warn+0x86/0xb0 kernel/panic.c:241
ubsan_epilogue lib/ubsan.c:222 [inline]
__ubsan_handle_out_of_bounds+0x141/0x150 lib/ubsan.c:415
diFree+0x21c3/0x2fb0 fs/jfs/jfs_imap.c:886
jfs_evict_inode+0x32d/0x440 fs/jfs/inode.c:156
evict+0x2a8/0x630 fs/inode.c:667
txUpdateMap+0x829/0x9f0 fs/jfs/jfs_txnmgr.c:2367
txLazyCommit fs/jfs/jfs_txnmgr.c:2664 [inline]
jfs_lazycommit+0x49a/0xb80 fs/jfs/jfs_txnmgr.c:2733
kthread+0x2f0/0x390 kernel/kthread.c:388
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>
Kernel Offset: disabled
Rebooting in 86400 seconds..

---
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