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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 4809CC07E9C for ; Sat, 10 Jul 2021 02:43:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3245E613CC for ; Sat, 10 Jul 2021 02:43:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234759AbhGJCpt (ORCPT ); Fri, 9 Jul 2021 22:45:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:33776 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235357AbhGJCnq (ORCPT ); Fri, 9 Jul 2021 22:43:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 61CCC613F2; Sat, 10 Jul 2021 02:39:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625884764; bh=gUwThY0EYXJoMtoHlTaJafFz+jl0r42OKpAgT6CENmk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JrKZ8w7/ZLDbg1Vpc2CuvjsEq2RtcZ+DHFzonVkLUb/sem6wSHfpVKliyRWLp7SmB 2jN1ctCcEBLtORHmwtZRAgPxOFh64Ik5tYWMCD6vdauMaMGm9RbOFZkLMmGojqyrLg KwAORS4iDm++DvvLlVlbcM+0ocZbHBplhR3deAe017NgMYe4B2NnGRZdvc2EXUpoAH 41ScJbzFitlwNvQ8uKXXd2AYzaXloOyZdHb+QGL3//L4kY6xjnWjJ8uZOVO1E0e6ZL b6F5/yebrfl2R6tZq3CbFxjRHjVp3LPeroZX+6gr7KeasSOzG9ji1AmzXdVgok8wec yar+iMOnvzKww== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Alan Stern , Johan Hovold , syzbot+7dbcd9ff34dc4ed45240@syzkaller.appspotmail.com, Greg Kroah-Hartman , Sasha Levin , linux-usb@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 09/23] USB: core: Avoid WARNings for 0-length descriptor requests Date: Fri, 9 Jul 2021 22:38:58 -0400 Message-Id: <20210710023912.3172972-9-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210710023912.3172972-1-sashal@kernel.org> References: <20210710023912.3172972-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alan Stern [ Upstream commit 60dfe484cef45293e631b3a6e8995f1689818172 ] The USB core has utility routines to retrieve various types of descriptors. These routines will now provoke a WARN if they are asked to retrieve 0 bytes (USB "receive" requests must not have zero length), so avert this by checking the size argument at the start. CC: Johan Hovold Reported-and-tested-by: syzbot+7dbcd9ff34dc4ed45240@syzkaller.appspotmail.com Reviewed-by: Johan Hovold Signed-off-by: Alan Stern Link: https://lore.kernel.org/r/20210607152307.GD1768031@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/core/message.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index e568325cb6e1..8b6e25f11d87 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -643,6 +643,9 @@ int usb_get_descriptor(struct usb_device *dev, unsigned char type, int i; int result; + if (size <= 0) /* No point in asking for no data */ + return -EINVAL; + memset(buf, 0, size); /* Make sure we parse really received data */ for (i = 0; i < 3; ++i) { @@ -691,6 +694,9 @@ static int usb_get_string(struct usb_device *dev, unsigned short langid, int i; int result; + if (size <= 0) /* No point in asking for no data */ + return -EINVAL; + for (i = 0; i < 3; ++i) { /* retry on length 0 or stall; some devices are flakey */ result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), -- 2.30.2