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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, 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 C11DBC433E0 for ; Thu, 16 Jul 2020 06:42:46 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8CC3B206F5 for ; Thu, 16 Jul 2020 06:42:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="xeBgH2yz"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b="XRXOcdeT" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8CC3B206F5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:To:From: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=ysBLNXa/W+WMHx/jhVx5iR+mlawmM5D3taG/5aEUCK4=; b=xeBgH2yzlpBdulbn12vrUpvCl9 F1pjEgbesHqL92gqdd2qPTtTa4dMVwIS2n6LzCB0vq5bvb8wGydTxZbfqL4yivstH63ZC2YoNrSJZ YqmD1+F6tw4+6h6nQdclRkvGj1vs08C7hpAcOxTZZU0RAxMLwC5WGZk8CzlTfAxyRDaD8AeWYzNU1 aaaV1aMIzyqGEDGNVfilO7XcfaAs0Zcbiu9hZ0RoqQcLkJobb2ReEmwlnKqqcuc0IA3HRw5sVnpa6 fcqlTN+JzyNPNRdzO0EDpHSi10W0GRN2w5jlDovZlMjmE8bPzMJen6ceZyqwkAyKBXDiHxunTtwt0 /AWs04LA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jvxaK-0000Xd-DX; Thu, 16 Jul 2020 06:41:36 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jvxaG-0000WE-1r; Thu, 16 Jul 2020 06:41:33 +0000 X-UUID: e92548ae80ef45aeaeed4abe9851409f-20200715 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Transfer-Encoding:Content-Type:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=Ho71eZkBMon4Vz3VLsPtyCt1CUgMlDiLHMKnef2ILSA=; b=XRXOcdeTwdFN5d5s8jX8hdz6O50rKSfYqC/FF81iO2+b53MPXL5/oC0kr7EVgPUpRORpRoYW96U7jERsz9vZ9HnAyr9cI8T9YQHHcldb5pesSvSRotu9pyGF/T3RirNz9Y82YCsHptjKZZ/PHrJZIhY7f3bsF0ReHtLCijHTROo=; X-UUID: e92548ae80ef45aeaeed4abe9851409f-20200715 Received: from mtkcas67.mediatek.inc [(172.29.193.45)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLS) with ESMTP id 1279607227; Wed, 15 Jul 2020 22:41:27 -0800 Received: from MTKMBS01N1.mediatek.inc (172.21.101.68) by MTKMBS62DR.mediatek.inc (172.29.94.18) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 15 Jul 2020 23:41:21 -0700 Received: from mtkcas08.mediatek.inc (172.21.101.126) by mtkmbs01n1.mediatek.inc (172.21.101.68) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 16 Jul 2020 14:41:20 +0800 Received: from mtkswgap22.mediatek.inc (172.21.77.33) by mtkcas08.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Thu, 16 Jul 2020 14:41:20 +0800 From: Macpaul Lin To: Felipe Balbi , Greg Kroah-Hartman , Matthias Brugger , , , , Subject: [PATCH] usb: gadget: configfs: Fix use-after-free issue with udc_name Date: Thu, 16 Jul 2020 14:41:06 +0800 Message-ID: <1594881666-8843-1-git-send-email-macpaul.lin@mediatek.com> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200716_024132_319814_80564F40 X-CRM114-Status: GOOD ( 11.54 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: stable@vger.kernel.org, Macpaul Lin , Eddie Hung , Macpaul Lin , Mediatek WSD Upstream Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org There is a use-after-free issue, if access udc_name in function gadget_dev_desc_UDC_store after another context free udc_name in function unregister_gadget. Contex 1: gadget_dev_desc_UDC_store()->unregister_gadget()-> free udc_name->set udc_name to NULL Contex 2: gadget_dev_desc_UDC_show()-> access udc_name Call trace: dump_backtrace+0x0/0x340 show_stack+0x14/0x1c dump_stack+0xe4/0x134 print_address_description+0x78/0x478 __kasan_report+0x270/0x2ec kasan_report+0x10/0x18 __asan_report_load1_noabort+0x18/0x20 string+0xf4/0x138 vsnprintf+0x428/0x14d0 sprintf+0xe4/0x12c gadget_dev_desc_UDC_show+0x54/0x64 configfs_read_file+0x210/0x3a0 __vfs_read+0xf0/0x49c vfs_read+0x130/0x2b4 SyS_read+0x114/0x208 el0_svc_naked+0x34/0x38 Add mutex_lock to protect this kind of scenario. Signed-off-by: Eddie Hung Signed-off-by: Macpaul Lin Cc: stable@vger.kernel.org --- drivers/usb/gadget/configfs.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c index 9dc06a4e1b30..21110b2865b9 100644 --- a/drivers/usb/gadget/configfs.c +++ b/drivers/usb/gadget/configfs.c @@ -221,9 +221,16 @@ static ssize_t gadget_dev_desc_bcdUSB_store(struct config_item *item, static ssize_t gadget_dev_desc_UDC_show(struct config_item *item, char *page) { - char *udc_name = to_gadget_info(item)->composite.gadget_driver.udc_name; + struct gadget_info *gi = to_gadget_info(item); + char *udc_name; + int ret; + + mutex_lock(&gi->lock); + udc_name = gi->composite.gadget_driver.udc_name; + ret = sprintf(page, "%s\n", udc_name ?: ""); + mutex_unlock(&gi->lock); - return sprintf(page, "%s\n", udc_name ?: ""); + return ret; } static int unregister_gadget(struct gadget_info *gi) -- 2.18.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel