On Tue, 09 Mar 2021 12:32:18 +0100, syzbot wrote:

Hello,

syzbot found the following issue on:

HEAD commit: 4641b323 Add linux-next specific files for 20210305 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=103252ead00000 kernel config: https://syzkaller.appspot.com/x/.config?x=b87b6a083d302a90 dashboard link: https://syzkaller.appspot.com/bug?extid=ffad4c74b3b3ea3aa9c3 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1122d35cd00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17f6476cd00000

The issue was bisected to:

commit 9799110825dba087c2bdce886977cf84dada2005 Author: Kai-Heng Feng kai.heng.feng@canonical.com Date: Thu Mar 4 04:34:16 2021 +0000

ALSA: usb-audio: Disable USB autosuspend properly in setup_disable_autosuspend()

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=166d91ead00000 final oops: https://syzkaller.appspot.com/x/report.txt?x=156d91ead00000 console output: https://syzkaller.appspot.com/x/log.txt?x=116d91ead00000

IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+ffad4c74b3b3ea3aa9c3@syzkaller.appspotmail.com Fixes: 9799110825db ("ALSA: usb-audio: Disable USB autosuspend properly in setup_disable_autosuspend()")

usb 1-1: USB disconnect, device number 2

BUG: KASAN: use-after-free in usb_audio_disconnect+0x750/0x800 sound/usb/card.c:918

This must be fixed by the commit that was already merged to sound.git tree today: c5aa956eaeb0 ("ALSA: usb-audio: fix use after free in usb_audio_disconnect")

thanks,

Takashi