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=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 470DAC4743C for ; Mon, 14 Jun 2021 10:39:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 33B0261482 for ; Mon, 14 Jun 2021 10:39:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233316AbhFNKlZ (ORCPT ); Mon, 14 Jun 2021 06:41:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:40206 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233426AbhFNKgR (ORCPT ); Mon, 14 Jun 2021 06:36:17 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id BC8EB613CD; Mon, 14 Jun 2021 10:33:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1623666782; bh=HiVe3URnuR0rBky5i/D8Wmii1TLvcIBRnTuKtx2WEw4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ftc2Lw/3AEGQP6pFpKM729pquNMuwmB8yvnGUenjt3jPF6D44S/elh8EQGJMSzjX3 3x9mTEjwaqpCk8IRRABeqKSr3IXvvf+e0SpidroEQHPHrReH+OsO/LHlN7fsNX3vw5 6wVjjWT9aUhw8DMLfvzRBT2FY2YleZ4V7fOBf4j8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marian-Cristian Rotariu Subject: [PATCH 4.14 28/49] usb: dwc3: ep0: fix NULL pointer exception Date: Mon, 14 Jun 2021 12:27:21 +0200 Message-Id: <20210614102642.790361172@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210614102641.857724541@linuxfoundation.org> References: <20210614102641.857724541@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marian-Cristian Rotariu commit d00889080ab60051627dab1d85831cd9db750e2a upstream. There is no validation of the index from dwc3_wIndex_to_dep() and we might be referring a non-existing ep and trigger a NULL pointer exception. In certain configurations we might use fewer eps and the index might wrongly indicate a larger ep index than existing. By adding this validation from the patch we can actually report a wrong index back to the caller. In our usecase we are using a composite device on an older kernel, but upstream might use this fix also. Unfortunately, I cannot describe the hardware for others to reproduce the issue as it is a proprietary implementation. [ 82.958261] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a4 [ 82.966891] Mem abort info: [ 82.969663] ESR = 0x96000006 [ 82.972703] Exception class = DABT (current EL), IL = 32 bits [ 82.978603] SET = 0, FnV = 0 [ 82.981642] EA = 0, S1PTW = 0 [ 82.984765] Data abort info: [ 82.987631] ISV = 0, ISS = 0x00000006 [ 82.991449] CM = 0, WnR = 0 [ 82.994409] user pgtable: 4k pages, 39-bit VAs, pgdp = 00000000c6210ccc [ 83.000999] [00000000000000a4] pgd=0000000053aa5003, pud=0000000053aa5003, pmd=0000000000000000 [ 83.009685] Internal error: Oops: 96000006 [#1] PREEMPT SMP [ 83.026433] Process irq/62-dwc3 (pid: 303, stack limit = 0x000000003985154c) [ 83.033470] CPU: 0 PID: 303 Comm: irq/62-dwc3 Not tainted 4.19.124 #1 [ 83.044836] pstate: 60000085 (nZCv daIf -PAN -UAO) [ 83.049628] pc : dwc3_ep0_handle_feature+0x414/0x43c [ 83.054558] lr : dwc3_ep0_interrupt+0x3b4/0xc94 ... [ 83.141788] Call trace: [ 83.144227] dwc3_ep0_handle_feature+0x414/0x43c [ 83.148823] dwc3_ep0_interrupt+0x3b4/0xc94 [ 83.181546] ---[ end trace aac6b5267d84c32f ]--- Signed-off-by: Marian-Cristian Rotariu Cc: stable Link: https://lore.kernel.org/r/20210608162650.58426-1-marian.c.rotariu@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc3/ep0.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/usb/dwc3/ep0.c +++ b/drivers/usb/dwc3/ep0.c @@ -302,6 +302,9 @@ static struct dwc3_ep *dwc3_wIndex_to_de epnum |= 1; dep = dwc->eps[epnum]; + if (dep == NULL) + return NULL; + if (dep->flags & DWC3_EP_ENABLED) return dep;