From 68359a1ad8447c99732ebeab8c169bfed543667a Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Fri, 10 Jul 2020 15:59:59 +0200
Subject: [PATCH] ALSA: line6: Sync the pending work cancel at disconnection
Git-commit: 68359a1ad8447c99732ebeab8c169bfed543667a
Patch-mainline: v5.8-rc6
References: jsc#SLE-16518
Recently syzkaller reported a UAF in LINE6 driver, and it's likely
because we call cancel_delayed_work() at the disconnect callback
instead of cancel_delayed_work_sync(). Let's use the correct one
instead.
Reported-by: syzbot+145012a46658ac00fc9e@syzkaller.appspotmail.com
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/s5hlfjr4gio.wl-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
sound/usb/line6/driver.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/usb/line6/driver.c b/sound/usb/line6/driver.c
index 7629116f570e..2746d9698180 100644
--- a/sound/usb/line6/driver.c
+++ b/sound/usb/line6/driver.c
@@ -840,7 +840,7 @@ void line6_disconnect(struct usb_interface *interface)
if (WARN_ON(usbdev != line6->usbdev))
return;
- cancel_delayed_work(&line6->startup_work);
+ cancel_delayed_work_sync(&line6->startup_work);
if (line6->urb_listen != NULL)
line6_stop_listen(line6);
--
2.16.4