UBSAN: shift-out-of-bounds in minix_statfs

Status: auto-obsoleted due to no activity on 2026/05/14 16:39
Reported-by: syzbot+38b8dae7ef383810df3d@syzkaller.appspotmail.com
First crash: 344d, last: 175d
Fix commit to backport (bisect log) :
tree: upstream
commit 7cd7bfe59328741185ef6db3356489c22919e59b
Author: Bill O'Donnell <bodonnel@redhat.com>
Date: Thu Mar 7 16:29:18 2024 +0000

  minix: convert minix to use the new mount api

  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2026/04/01 upstream (ToT) 9147566d8016 C Didn't crash
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 UBSAN: shift-out-of-bounds in minix_statfs origin:upstream -1 syz, C error 6 269d 626d 0/3 upstream: reported C repro on 2024/11/09 11:46
upstream UBSAN: shift-out-of-bounds in minix_statfs fs -1 syz, C inconclusive error 75 183d 1688d 29/29 fixed on 2026/05/06 16:40
▶ ▼ Last patch testing requests (6)
Created Duration User Patch Repo Result
2026/03/31 17:14 26m retest repro linux-5.15.y OK log
2026/03/31 17:14 16m retest repro linux-5.15.y OK log
2026/02/03 16:26 16m retest repro linux-5.15.y error
2026/02/03 16:26 12m retest repro linux-5.15.y report log
2026/01/20 15:31 10m retest repro linux-5.15.y report log
2026/01/20 15:31 11m retest repro linux-5.15.y report log
▶ ▼ Fix bisection attempts (1)
Created Duration User Patch Repo Result
2025/10/07 13:10 8h39m fix candidate upstream OK (1) job log

Sample crash report:
loop0: detected capacity change from 0 to 64
================================================================================
UBSAN: shift-out-of-bounds in fs/minix/inode.c:380:57
shift exponent 13056 is too large for 64-bit type 'unsigned long'
CPU: 0 PID: 4312 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 ubsan_epilogue+0xa/0x30 lib/ubsan.c:151
 __ubsan_handle_shift_out_of_bounds+0x37c/0x400 lib/ubsan.c:321
 minix_statfs+0x313/0x340 fs/minix/inode.c:380
 statfs_by_dentry fs/statfs.c:66 [inline]
 vfs_statfs fs/statfs.c:90 [inline]
 user_statfs+0x1f3/0x5b0 fs/statfs.c:105
 __do_sys_statfs fs/statfs.c:195 [inline]
 __se_sys_statfs fs/statfs.c:192 [inline]
 __x64_sys_statfs+0xdd/0x1a0 fs/statfs.c:192
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f46c68b8749
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:00007ffe5aa2a1c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000089
RAX: ffffffffffffffda RBX: 00007f46c6b0efa0 RCX: 00007f46c68b8749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000000c0
RBP: 00007f46c693cf91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f46c6b0efa0 R14: 00007f46c6b0efa0 R15: 0000000000000002
 </TASK>
================================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/04 22:41 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan UBSAN: shift-out-of-bounds in minix_statfs
2025/08/18 10:46 linux-5.15.y c79648372d02 1804e95e .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan UBSAN: shift-out-of-bounds in minix_statfs
2025/08/18 09:52 linux-5.15.y c79648372d02 1804e95e .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan UBSAN: shift-out-of-bounds in minix_statfs
2025/08/18 08:52 linux-5.15.y c79648372d02 1804e95e .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-5-15-kasan UBSAN: shift-out-of-bounds in minix_statfs
2025/08/18 07:51 linux-5.15.y c79648372d02 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan UBSAN: shift-out-of-bounds in minix_statfs
* Struck through repros no longer work on HEAD.