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

[syzbot <syzbot+9120834fc227768625ba@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    59dbb9d81adf Merge tag 'xsa465+xsa466-6.13-tag' of git://g..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15a64b44580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6a2b862bf4a5409f
dashboard link: https://syzkaller.appspot.com/bug?extid=9120834fc227768625ba
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-59dbb9d8.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e0cc89779297/vmlinux-59dbb9d8.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5e6c895062cb/bzImage-59dbb9d8.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9120834fc227768625ba@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 32768
syz.0.0: attempt to access beyond end of device
loop0: rw=1, sector=4680032, nr_sectors = 8 limit=32768
metapage_write_end_io: I/O error
ERROR: (device loop0): release_metapage: metapage_write_one() failed
ERROR: (device loop0): remounting filesystem as read-only
blkno = 8ed2c, nblocks = 1
ERROR: (device loop0): dbUpdatePMap: blocks are outside the map
blkno = 8ed2c, nblocks = 1
ERROR: (device loop0): dbUpdatePMap: blocks are outside the map
UFO tlock:0xffffc90001537090
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dtree.c:3096:10
index 237 is out of range for type 'struct dtslot[128]'
CPU: 0 UID: 0 PID: 5314 Comm: syz.0.0 Not tainted 6.13.0-rc3-syzkaller-00026-g59dbb9d81adf #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_out_of_bounds+0x121/0x150 lib/ubsan.c:429
 dtReadFirst+0x622/0xc50 fs/jfs/jfs_dtree.c:3096
 dtReadNext fs/jfs/jfs_dtree.c:3147 [inline]
 jfs_readdir+0x9aa/0x3c50 fs/jfs/jfs_dtree.c:2862
 wrap_directory_iterator+0x91/0xd0 fs/readdir.c:65
 iterate_dir+0x571/0x800 fs/readdir.c:108
 __do_sys_getdents fs/readdir.c:322 [inline]
 __se_sys_getdents+0x1fd/0x4e0 fs/readdir.c:308
 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: 0033:0x7f6e27385d29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6e28204038 EFLAGS: 00000246 ORIG_RAX: 000000000000004e
RAX: ffffffffffffffda RBX: 00007f6e27575fa0 RCX: 00007f6e27385d29
RDX: 00000000000000b8 RSI: 0000000020001fc0 RDI: 0000000000000005
RBP: 00007f6e27401a20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f6e27575fa0 R15: 00007ffdef535ad8
 </TASK>
---[ end trace ]---


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup