[syzbot] KMSAN: uninit-value in snd_rawmidi_ioctl

From: syzbot <syzbot+88412ee8811832b00dbe@syzkaller.appspotmail.com>
To: alsa-devel@alsa-project.org, broonie@kernel.org, coding@diwic.se,
	colin.king@intel.com, glider@google.com, joe@perches.com,
	linux-kernel@vger.kernel.org, perex@perex.cz,
	syzkaller-bugs@googlegroups.com, tiwai@suse.com
Subject: [syzbot] KMSAN: uninit-value in snd_rawmidi_ioctl
Date: Sat, 18 Dec 2021 03:17:32 -0800	[thread overview]
Message-ID: <0000000000004255b405d369cd72@google.com> (raw)

Hello,

syzbot found the following issue on:

HEAD commit:    8b936c96768e kmsan: core: remove the accidentally committe..
git tree:       https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=11791d89b00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e00a8959fdd3f3e8
dashboard link: https://syzkaller.appspot.com/bug?extid=88412ee8811832b00dbe
compiler:       clang version 14.0.0 (git@github.com:llvm/llvm-project.git 0996585c8e3b3d409494eb5f1cad714b9e1f7fb5), GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=13a7abf9b00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=172410b9b00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+88412ee8811832b00dbe@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in snd_rawmidi_ioctl+0xf1e/0x1330 sound/core/rawmidi.c:887
 snd_rawmidi_ioctl+0xf1e/0x1330 sound/core/rawmidi.c:887
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0x2df/0x4a0 fs/ioctl.c:860
 __x64_sys_ioctl+0xd8/0x110 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:524 [inline]
 slab_alloc_node mm/slub.c:3251 [inline]
 slab_alloc mm/slub.c:3259 [inline]
 kmem_cache_alloc_trace+0xaca/0x1140 mm/slub.c:3276
 kmalloc include/linux/slab.h:590 [inline]
 snd_rawmidi_open+0x70d/0x1390 sound/core/rawmidi.c:445
 snd_open+0x702/0x890 sound/core/sound.c:169
 chrdev_open+0xbc9/0xd80 fs/char_dev.c:414
 do_dentry_open+0x1128/0x1bf0 fs/open.c:822
 vfs_open+0xaf/0xe0 fs/open.c:957
 do_open fs/namei.c:3426 [inline]
 path_openat+0x52f1/0x5dd0 fs/namei.c:3559
 do_filp_open+0x306/0x760 fs/namei.c:3586
 do_sys_openat2+0x263/0x8f0 fs/open.c:1212
 do_sys_open fs/open.c:1228 [inline]
 __do_sys_openat fs/open.c:1244 [inline]
 __se_sys_openat fs/open.c:1239 [inline]
 __x64_sys_openat+0x35f/0x3c0 fs/open.c:1239
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

CPU: 1 PID: 6368 Comm: syz-executor467 Not tainted 5.16.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
=====================================================

---
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