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 jfs_lookup: dtSearch returned -5 jfs_lookup: dtSearch returned -5 find_entry called with index >= next_index ------------[ cut here ]------------ UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dtree.c:1998:37 index -128 is out of range for type 'struct dtslot[128]' CPU: 0 UID: 0 PID: 5318 Comm: syz.0.0 Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #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: 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 dtSplitRoot+0xae9/0x16c0 fs/jfs/jfs_dtree.c:1998 dtSplitUp fs/jfs/jfs_dtree.c:993 [inline] dtInsert+0xef8/0x5f40 fs/jfs/jfs_dtree.c:871 jfs_mkdir+0x6ec/0xa70 fs/jfs/namei.c:270 vfs_mkdir+0x303/0x510 fs/namei.c:4359 do_mkdirat+0x247/0x590 fs/namei.c:4392 __do_sys_mkdirat fs/namei.c:4409 [inline] __se_sys_mkdirat fs/namei.c:4407 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4407 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: 0033:0x7f8baaf8e969 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:00007f8ba73f5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f8bab1b5fa0 RCX: 00007f8baaf8e969 RDX: 0000000000000000 RSI: 0000200000000440 RDI: ffffffffffffff9c RBP: 00007f8bab010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f8bab1b5fa0 R15: 00007ffc12beefa8 ---[ end trace ]---