From: syzbot <syzbot+9e3014263a35700ab49b@syzkaller.appspotmail.com>
To: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org,
magiclinan@didiglobal.com, song@kernel.org,
syzkaller-bugs@googlegroups.com, xiao@kernel.org,
yukuai@fnnas.com, yukuai@fygo.io
Subject: Re: [syzbot] [raid?] UBSAN: array-index-out-of-bounds in super_90_sync
Date: Sun, 13 Sep 2026 10:34:36 -0700 [thread overview]
Message-ID: <6aa6deac.f670cee1.72fc4.0013.GAE@google.com> (raw)
In-Reply-To: <6aa6a091.f670cee1.72fc4.0012.GAE@google.com>
syzbot has found a reproducer for the following issue on:
HEAD commit: 2f0c1cf72f46 Merge tag 's390-7.3-3' of git://git.kernel.or..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=14afd5f9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=8c5c3949d762a91f
dashboard link: https://syzkaller.appspot.com/bug?extid=9e3014263a35700ab49b
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12afd5f9580000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9e3014263a35700ab49b@syzkaller.appspotmail.com
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in drivers/md/md.c:1697:17
index 124 is out of range for type 'mdp_disk_t [27]'
CPU: 1 UID: 0 PID: 6018 Comm: syz-executor186 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
ubsan_epilogue+0xa/0x30 lib/ubsan.c:233
__ubsan_handle_out_of_bounds+0xcc/0xf0 lib/ubsan.c:455
super_90_sync+0x1eed/0x1ff0 drivers/md/md.c:1697
sync_super drivers/md/md.c:2505 [inline]
sync_sbs drivers/md/md.c:2747 [inline]
md_update_sb+0xbba/0x2840 drivers/md/md.c:2923
state_store+0x31e/0x1340 drivers/md/md.c:3245
rdev_attr_store+0x1d9/0x560 drivers/md/md.c:3768
sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6af/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f84634ad6f7
Code: 48 89 fa 4c 89 df e8 98 1d 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fff04c70ef0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00005555934c5400 RCX: 00007f84634ad6f7
RDX: 0000000000000008 RSI: 00007f84634e9c12 RDI: 0000000000000003
RBP: 00007f84634e9c12 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff04c70fc0
R13: 00007f84634e9b5f R14: 00007fff04c710d0 R15: 0000000000000002
</TASK>
---[ end trace ]---
---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
prev parent reply other threads:[~2026-09-13 17:34 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-13 13:09 [syzbot] [raid?] UBSAN: array-index-out-of-bounds in super_90_sync syzbot
2026-09-13 17:34 ` syzbot [this message]
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