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

[syzbot <syzbot+b974bd41515f770c608b@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    28eb75e178d3 Merge tag 'drm-next-2024-11-21' of https://gi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10ad3930580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=402159daa216c89d
dashboard link: https://syzkaller.appspot.com/bug?extid=b974bd41515f770c608b
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: https://storage.googleapis.com/syzbot-assets/e3c9c97af7d9/disk-28eb75e1.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1e22f3d29103/vmlinux-28eb75e1.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8ff56ec30fa6/bzImage-28eb75e1.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b974bd41515f770c608b@syzkaller.appspotmail.com

------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dtree.c:2649:28
index -128 is out of range for type 'struct dtslot[128]'
CPU: 1 UID: 0 PID: 9494 Comm: syz.7.422 Not tainted 6.12.0-syzkaller-07749-g28eb75e178d3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
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
 add_missing_indices+0x824/0xbf0 fs/jfs/jfs_dtree.c:2649
 jfs_readdir+0x1fc5/0x3c50 fs/jfs/jfs_dtree.c:3019
 wrap_directory_iterator+0x91/0xd0 fs/readdir.c:65
 iterate_dir+0x571/0x800 fs/readdir.c:108
 __do_sys_getdents64 fs/readdir.c:403 [inline]
 __se_sys_getdents64+0x1e2/0x4b0 fs/readdir.c:389
 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: 0033:0x7fbaf317e819
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:00007fbaf3f2d038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007fbaf3335fa0 RCX: 00007fbaf317e819
RDX: 0000000000001000 RSI: 0000000020000f80 RDI: 0000000000000004
RBP: 00007fbaf31f175e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbaf3335fa0 R15: 00007fff928fc148
 </TASK>
---[ end trace ]---


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