From:   Dongliang Mu <mudongliangabcd@gmail.com>
To:     Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Dongliang Mu <mudongliangabcd@gmail.com>,
        Greg Kroah-Hartman <gregkh@suse.de>
Cc:     syzbot+9780d2b05ac158d32284@syzkaller.appspotmail.com,
        Dmitry Torokhov <dtor@insightbb.com>,
        linux-input@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] driver: powermate: kill urb in the disconnect function
Date:   Sun, 19 Dec 2021 14:02:15 +0800
Message-Id: <20211219060241.4125076-1-mudongliangabcd@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

In powermate_disconnect, powermate_pulse_led will invoke
powermate_sync_state and submit one urb with pm as its context.
If powermate disconnect before the execution of complete handler,
the pm will become a dangling pointer and lead to UAF.

Fix this by calling usb_kill_urb(pm->config) in the disconnect function.
Note that, the error handling error does not need to take care of this.

Reported-by: syzbot+9780d2b05ac158d32284@syzkaller.appspotmail.com
Fixes: ba0acb5ee318901 ("Input: move USB miscellaneous devices under drivers/input/misc")
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
---
 drivers/input/misc/powermate.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/input/misc/powermate.c b/drivers/input/misc/powermate.c
index c4e0e1886061..903993469fde 100644
--- a/drivers/input/misc/powermate.c
+++ b/drivers/input/misc/powermate.c
@@ -424,6 +424,7 @@ static void powermate_disconnect(struct usb_interface *intf)
 	if (pm) {
 		pm->requires_update = 0;
 		usb_kill_urb(pm->irq);
+		usb_kill_urb(pm->config);
 		input_unregister_device(pm->input);
 		usb_free_urb(pm->irq);
 		usb_free_urb(pm->config);
-- 
2.25.1