From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0CFD5C32750 for ; Fri, 2 Aug 2019 09:55:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CF1682064A for ; Fri, 2 Aug 2019 09:55:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564739700; bh=OufKD8J6lv8iRq2T8OhHfNlKOq+SpB83ycK3WdKvSvI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=H28O9vGYimemyFOqSFR4g4NZ2FX/DxPle/NUPVraHES4Nz1/PqWLQJO2PDLgfcukj wJwgC+qwBIjkx5tgtk8SjXah8ZXQD9+1+7+0A1MOhzgL3/Mr/zxppB430uPb5wGjMq RKQPHHskucHsdbVu8e0XvXAobYP6rWcl9S7ERIL0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406461AbfHBJy7 (ORCPT ); Fri, 2 Aug 2019 05:54:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:59716 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405891AbfHBJxb (ORCPT ); Fri, 2 Aug 2019 05:53:31 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 842442064A; Fri, 2 Aug 2019 09:53:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564739611; bh=OufKD8J6lv8iRq2T8OhHfNlKOq+SpB83ycK3WdKvSvI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=D53CHPRL651MrdOzMmNlsmbziWtMk1zjKowI07qqJ31GsV+TFC/4xSez8+5nOUtHi 6hH52l3+0JL5AGmuxvKVFgfY99Oz0aX3d8EQoopoNIFiUKSvwNqy161rUCyTGZa2Y0 6j+G2jATkQjF9i3GP7MbKc6mVTWE68tN0TXiT7JE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Oliver Neukum , syzbot+0c90fc937c84f97d0aa6@syzkaller.appspotmail.com, Hans Verkuil , Mauro Carvalho Chehab Subject: [PATCH 4.9 218/223] media: cpia2_usb: first wake up, then free in disconnect Date: Fri, 2 Aug 2019 11:37:23 +0200 Message-Id: <20190802092250.799616900@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190802092238.692035242@linuxfoundation.org> References: <20190802092238.692035242@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Oliver Neukum commit eff73de2b1600ad8230692f00bc0ab49b166512a upstream. Kasan reported a use after free in cpia2_usb_disconnect() It first freed everything and then woke up those waiting. The reverse order is correct. Fixes: 6c493f8b28c67 ("[media] cpia2: major overhaul to get it in a working state again") Signed-off-by: Oliver Neukum Reported-by: syzbot+0c90fc937c84f97d0aa6@syzkaller.appspotmail.com Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/usb/cpia2/cpia2_usb.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/media/usb/cpia2/cpia2_usb.c +++ b/drivers/media/usb/cpia2/cpia2_usb.c @@ -909,7 +909,6 @@ static void cpia2_usb_disconnect(struct cpia2_unregister_camera(cam); v4l2_device_disconnect(&cam->v4l2_dev); mutex_unlock(&cam->v4l2_lock); - v4l2_device_put(&cam->v4l2_dev); if(cam->buffers) { DBG("Wakeup waiting processes\n"); @@ -921,6 +920,8 @@ static void cpia2_usb_disconnect(struct DBG("Releasing interface\n"); usb_driver_release_interface(&cpia2_driver, intf); + v4l2_device_put(&cam->v4l2_dev); + LOG("CPiA2 camera disconnected.\n"); }