From: Takashi Iwai <tiwai@suse.de> stable inclusion from stable-v5.10.121 commit 40bdb5ec957aca5c5c1924602bef6b0ab18e22d3 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBP6ZR CVE: CVE-2022-49545 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 0125de38122f0f66bf61336158d12a1aabfe6425 upstream. At closing a USB MIDI output substream, there might be still a pending work, which would eventually access the rawmidi runtime object that is being released. For fixing the race, make sure to cancel the pending work at closing. Reported-by: syzbot+6912c9592caca7ca0e7d@syzkaller.appspotmail.com Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/000000000000e7e75005dfd07cf6@google.com Link: https://lore.kernel.org/r/20220525131203.11299-1-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zhang Kunbo <zhangkunbo@huawei.com> --- sound/usb/midi.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/sound/usb/midi.c b/sound/usb/midi.c index dcfc546d81b9..4ec7cbdddfd0 100644 --- a/sound/usb/midi.c +++ b/sound/usb/midi.c @@ -1161,6 +1161,9 @@ static int snd_usbmidi_output_open(struct snd_rawmidi_substream *substream) static int snd_usbmidi_output_close(struct snd_rawmidi_substream *substream) { + struct usbmidi_out_port *port = substream->runtime->private_data; + + cancel_work_sync(&port->ep->work); return substream_open(substream, 0, 0); } -- 2.34.1