loop0: detected capacity change from 0 to 256
msdos: Unknown parameter 'ÿ0xffffffffffffffff'
loop0: detected capacity change from 0 to 32768
 ... Log Wrap ... Log Wrap ... Log Wrap ...
ERROR: (device loop0): jfs_readdir: JFS:Dtree error: ino = 2, bn=0, index = 0
JFS: Invalid stbl[1] = -128 for inode 2, block = 0
 ... Log Wrap ... Log Wrap ... Log Wrap ...
 ... Log Wrap ... Log Wrap ... Log Wrap ...
 ... Log Wrap ... Log Wrap ... Log Wrap ...
 ... Log Wrap ... Log Wrap ... Log Wrap ...
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dtree.c:2650:28
index -128 is out of range for type 'struct dtslot[128]'
CPU: 0 UID: 0 PID: 5311 Comm: syz.0.0 Not tainted 6.15.0-rc4-syzkaller-00040-g8bac8898fe39 #0 PREEMPT(full) 
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_lvl+0x189/0x250 lib/dump_stack.c:120
 ubsan_epilogue+0xa/0x40 lib/ubsan.c:231
 __ubsan_handle_out_of_bounds+0xe9/0xf0 lib/ubsan.c:453
 add_missing_indices+0x6a2/0xbc0 fs/jfs/jfs_dtree.c:2650
 jfs_readdir+0x1da4/0x3ac0 fs/jfs/jfs_dtree.c:3020
 wrap_directory_iterator+0x93/0xe0 fs/readdir.c:65
 iterate_dir+0x5ac/0x770 fs/readdir.c:108
 __do_sys_getdents64 fs/readdir.c:403 [inline]
 __se_sys_getdents64+0xe4/0x260 fs/readdir.c:389
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f984598e969
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:00007f9846778038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f9845bb6080 RCX: 00007f984598e969
RDX: 0000000000001000 RSI: 0000200000000f80 RDI: 000000000000000b
RBP: 00007f9845a10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f9845bb6080 R15: 00007ffda6468ff8
 </TASK>
---[ end trace ]---