syzbot


UBSAN: array-index-out-of-bounds in add_missing_indices

Status: upstream: reported on 2025/07/04 21:27
Reported-by: syzbot+34272791bb194e2b8b24@syzkaller.appspotmail.com
First crash: 13d, last: 9d17h
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream UBSAN: array-index-out-of-bounds in add_missing_indices jfs 15 C 187 38d 233d 29/29 fixed on 2025/07/08 00:33
linux-6.1 UBSAN: array-index-out-of-bounds in add_missing_indices origin:upstream missing-backport 19 C error 8 9d18h 185d 0/3 upstream: reported C repro on 2025/01/13 05:49
linux-5.15 UBSAN: array-index-out-of-bounds in add_missing_indices origin:upstream 19 C error 7 41d 165d 0/3 upstream: reported C repro on 2025/02/02 08:00

Sample crash report:
jfs_rename did not expect dtDelete to return rc = -5
ERROR: (device loop3): jfs_rename: 
================================================================================
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 PID: 5964 Comm: syz.3.12 Not tainted 6.6.96-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
 ubsan_epilogue+0xa/0x30 lib/ubsan.c:217
 __ubsan_handle_out_of_bounds+0xe3/0xf0 lib/ubsan.c:348
 add_missing_indices+0x6a0/0xbb0 fs/jfs/jfs_dtree.c:2650
 jfs_readdir+0x1d80/0x3a90 fs/jfs/jfs_dtree.c:3020
 wrap_directory_iterator+0x92/0xd0 fs/readdir.c:67
 iterate_dir+0x1c2/0x580 fs/readdir.c:106
 __do_sys_getdents64 fs/readdir.c:405 [inline]
 __se_sys_getdents64+0xe9/0x260 fs/readdir.c:390
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8d5818e929
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:00007f8d58f73038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f8d583b5fa0 RCX: 00007f8d5818e929
RDX: 0000000000001000 RSI: 0000200000000f80 RDI: 0000000000000004
RBP: 00007f8d58210b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8d583b5fa0 R15: 00007fffbaa6f5e8
 </TASK>
================================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/08 09:57 linux-6.6.y a5df3a702b2c 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan UBSAN: array-index-out-of-bounds in add_missing_indices
2025/07/08 09:54 linux-6.6.y a5df3a702b2c 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan UBSAN: array-index-out-of-bounds in add_missing_indices
2025/07/04 21:27 linux-6.6.y 3f5b4c104b7d d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan UBSAN: array-index-out-of-bounds in add_missing_indices
2025/07/04 21:26 linux-6.6.y 3f5b4c104b7d d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan UBSAN: array-index-out-of-bounds in add_missing_indices
* Struck through repros no longer work on HEAD.