From patchwork Mon Mar 21 08:47:07 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans Verkuil X-Patchwork-Id: 553655 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1A6BBC433F5 for ; Mon, 21 Mar 2022 08:47:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345398AbiCUIsl (ORCPT ); Mon, 21 Mar 2022 04:48:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41068 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345430AbiCUIsi (ORCPT ); Mon, 21 Mar 2022 04:48:38 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B40FA76CF for ; Mon, 21 Mar 2022 01:47:10 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 1B6276112D for ; Mon, 21 Mar 2022 08:47:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 45E59C340E8 for ; Mon, 21 Mar 2022 08:47:09 +0000 (UTC) Message-ID: Date: Mon, 21 Mar 2022 09:47:07 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.1 Content-Language: en-US To: Linux Media Mailing List From: Hans Verkuil Subject: [PATCH for v5.18] v4l2-ioctl.c: fix incorrect error path Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org If allocating array_buf fails, or copying data from userspace into that buffer fails, then just free memory and return the error. Don't attempt to call video_put_user() since there is no point. If writing the array back to userspace fails, then don't go to out_array_args, instead just continue with the regular code that just returns the error unless 'always_copy' is set. That flag was just completely ignored when writing back the array data. Signed-off-by: Hans Verkuil diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c index 96e307fe3aab..92433234c430 100644 --- a/drivers/media/v4l2-core/v4l2-ioctl.c +++ b/drivers/media/v4l2-core/v4l2-ioctl.c @@ -3311,7 +3311,7 @@ video_usercopy(struct file *file, unsigned int orig_cmd, unsigned long arg, array_buf = kvmalloc(array_size, GFP_KERNEL); err = -ENOMEM; if (array_buf == NULL) - goto out_array_args; + goto out; err = -EFAULT; if (in_compat_syscall()) err = v4l2_compat_get_array_args(file, array_buf, @@ -3321,7 +3321,7 @@ video_usercopy(struct file *file, unsigned int orig_cmd, unsigned long arg, err = copy_from_user(array_buf, user_ptr, array_size) ? -EFAULT : 0; if (err) - goto out_array_args; + goto out; *kernel_ptr = array_buf; } @@ -3353,7 +3353,6 @@ video_usercopy(struct file *file, unsigned int orig_cmd, unsigned long arg, } else if (copy_to_user(user_ptr, array_buf, array_size)) { err = -EFAULT; } - goto out_array_args; } /* * Some ioctls can return an error, but still have valid