Commit 3a163f36 authored Jul 10, 2020 by Takashi Iwai Committed by Greg Kroah-Hartman Jul 22, 2020

ALSA: line6: Sync the pending work cancel at disconnection



commit 68359a1ad8447c99732ebeab8c169bfed543667a upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 5ca7b059

sound/usb/line6/driver.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -835,7 +835,7 @@ 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);