loop2: detected capacity change from 0 to 32768
 ... Log Wrap ... Log Wrap ... Log Wrap ...
ERROR: (device loop2): jfs_readdir: JFS:Dtree error: ino = 2, bn=0, index = 0
================================================================================
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dtree.c:3190:30
index -128 is out of range for type 'struct dtslot[128]'
CPU: 1 PID: 9663 Comm: syz.2.1503 Not tainted 5.15.173-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 ubsan_epilogue lib/ubsan.c:151 [inline]
 __ubsan_handle_out_of_bounds+0x118/0x140 lib/ubsan.c:282
 jfs_readdir+0x1d40/0x4650 fs/jfs/jfs_dtree.c:3190
 iterate_dir+0x224/0x570
 __do_sys_getdents64 fs/readdir.c:369 [inline]
 __se_sys_getdents64+0x209/0x4f0 fs/readdir.c:354
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2a51a60809
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:00007f2a4f8d6058 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f2a51c25fa0 RCX: 00007f2a51a60809
RDX: 0000000000001000 RSI: 0000000020000f80 RDI: 0000000000000004
RBP: 00007f2a51ad393e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f2a51c25fa0 R15: 00007ffd2b6c3538
 </TASK>
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