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=-12.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 AB11DC10F13 for ; Tue, 16 Apr 2019 10:39:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 750CF20693 for ; Tue, 16 Apr 2019 10:39:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555411167; bh=RRy1YdbNrPe1OMEL9dOjpmzdY8WJA3A83RPv/MqiWG4=; h=Subject:To:From:Date:List-ID:From; b=YFh8lj7tUVhYUHJGwoHFnnvMLhIRroGub2TT2O8IbTxZy2g2a5lbKh/XsZbJBHEF/ Vs2F2YCWo7EQPibPsmrUaUZBuiE/G0zbe6U4YmwLT0eZBNBHBzaANt7uMFKn0uSAMj 5hlBbvGNm9rONoBMA+VCmkWBFVnTSS2g8GWrg5LM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728360AbfDPKj1 (ORCPT ); Tue, 16 Apr 2019 06:39:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:58158 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727950AbfDPKj0 (ORCPT ); Tue, 16 Apr 2019 06:39:26 -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 71CBF20693; Tue, 16 Apr 2019 10:39:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555411165; bh=RRy1YdbNrPe1OMEL9dOjpmzdY8WJA3A83RPv/MqiWG4=; h=Subject:To:From:Date:From; b=uHXM9Hr8YQSB7cUz8t6U41QFdOBBmkNHP7xgiaVnI3R++MNQYaIVIiutrRtSS7f9m QvxlHVZ4GZCAm8vPSEuXHmpnFiTFL0djLQdsPLskmvlvUPPxIZwoFERY33f5C88kwk QjhgV2RZna4rBuDZzm5j0A23EaLKGp4X8qYyD4+E= Subject: patch "USB: core: Fix unterminated string returned by usb_string()" added to usb-linus To: stern@rowland.harvard.edu, gregkh@linuxfoundation.org, stable@vger.kernel.org From: Date: Tue, 16 Apr 2019 12:25:04 +0200 Message-ID: <155541030455104@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is a note to let you know that I've just added the patch titled USB: core: Fix unterminated string returned by usb_string() to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From c01c348ecdc66085e44912c97368809612231520 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Mon, 15 Apr 2019 11:51:38 -0400 Subject: USB: core: Fix unterminated string returned by usb_string() Some drivers (such as the vub300 MMC driver) expect usb_string() to return a properly NUL-terminated string, even when an error occurs. (In fact, vub300's probe routine doesn't bother to check the return code from usb_string().) When the driver goes on to use an unterminated string, it leads to kernel errors such as stack-out-of-bounds, as found by the syzkaller USB fuzzer. An out-of-range string index argument is not at all unlikely, given that some devices don't provide string descriptors and therefore list 0 as the value for their string indexes. This patch makes usb_string() return a properly terminated empty string along with the -EINVAL error code when an out-of-range index is encountered. And since a USB string index is a single-byte value, indexes >= 256 are just as invalid as values of 0 or below. Signed-off-by: Alan Stern Reported-by: syzbot+b75b85111c10b8d680f1@syzkaller.appspotmail.com CC: Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/message.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 82239f27c4cc..e844bb7b5676 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -820,9 +820,11 @@ int usb_string(struct usb_device *dev, int index, char *buf, size_t size) if (dev->state == USB_STATE_SUSPENDED) return -EHOSTUNREACH; - if (size <= 0 || !buf || !index) + if (size <= 0 || !buf) return -EINVAL; buf[0] = 0; + if (index <= 0 || index >= 256) + return -EINVAL; tbuf = kmalloc(256, GFP_NOIO); if (!tbuf) return -ENOMEM; -- 2.21.0