loop5: detected capacity change from 0 to 32768 ------------[ cut here ]------------ UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:2257:2 index -2147483648 is out of range for type 's64[128]' (aka 'long long[128]') CPU: 1 UID: 0 PID: 13401 Comm: syz.5.837 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 ubsan_epilogue+0xa/0x30 lib/ubsan.c:233 __ubsan_handle_out_of_bounds+0xe8/0xf0 lib/ubsan.c:455 dbAllocBits+0xa07/0xa60 fs/jfs/jfs_dmap.c:2257 dbAllocDmap fs/jfs/jfs_dmap.c:2034 [inline] dbAllocNear+0x2aa/0x3d0 fs/jfs/jfs_dmap.c:1247 dbAlloc+0x936/0xba0 fs/jfs/jfs_dmap.c:832 diNewExt+0x9b0/0x3150 fs/jfs/jfs_imap.c:2261 diAllocExt fs/jfs/jfs_imap.c:1952 [inline] diAllocAG+0xeb1/0x1db0 fs/jfs/jfs_imap.c:1669 diAlloc+0x1d4/0x1670 fs/jfs/jfs_imap.c:1590 ialloc+0x8c/0x8f0 fs/jfs/jfs_inode.c:56 jfs_mkdir+0x1e1/0xb00 fs/jfs/namei.c:226 vfs_mkdir+0x40b/0x630 fs/namei.c:5239 filename_mkdirat+0x289/0x520 fs/namei.c:5272 __do_sys_mkdirat fs/namei.c:5293 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5290 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f387733c819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f387558e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f38775b5fa0 RCX: 00007f387733c819 RDX: 0000000000000000 RSI: 00002000000000c0 RDI: ffffffffffffff9c RBP: 00007f38773d2c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f38775b6038 R14: 00007f38775b5fa0 R15: 00007ffc68492cc8 ---[ end trace ]---