From patchwork Sun Aug 11 23:55:07 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 11089203 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 25E3A14F7 for ; Mon, 12 Aug 2019 00:18:09 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1783727DA4 for ; Mon, 12 Aug 2019 00:18:09 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 03C4B27F10; Mon, 12 Aug 2019 00:18:08 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EB0CB27F10 for ; Mon, 12 Aug 2019 00:18:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726718AbfHLASE (ORCPT ); Sun, 11 Aug 2019 20:18:04 -0400 Received: from gateway20.websitewelcome.com ([192.185.67.41]:43473 "EHLO gateway20.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725870AbfHLASE (ORCPT ); Sun, 11 Aug 2019 20:18:04 -0400 X-Greylist: delayed 1373 seconds by postgrey-1.27 at vger.kernel.org; Sun, 11 Aug 2019 20:18:03 EDT Received: from cm11.websitewelcome.com (cm11.websitewelcome.com [100.42.49.5]) by gateway20.websitewelcome.com (Postfix) with ESMTP id 95FB0400C5814 for ; Sun, 11 Aug 2019 17:51:00 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id wxg5hoVTOdnCewxg5hFMNN; Sun, 11 Aug 2019 18:55:09 -0500 X-Authority-Reason: nr=8 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=embeddedor.com; s=default; h=Content-Type:MIME-Version:Message-ID:Subject: Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=yKwbRY2mzkRaJ05KgpOoqO2JTy1EKQ64ZrdyRyqRkM8=; b=j7ccFO9QZypPjQRoMtoJIfjAZR 7zJ7WUNAzwhixXYm3tR3Fcf0LU/ZSw/7IcF3SQLgAkz4APb0e23Yab0fYiQH+L9nT2xDDWdMwdQHf Z3K+eNfMR62JKvEQsbqPvWjoDtO/s8limUAlMq1jXbmN0RwMzaBXYLCR5wcS2TPUwaXQqeKUkK2ns Mdt7NVJJjAdnBGRaFMBK3QoJ6PFzM1FlfOr5gA0MkVjsHxfut8kICDpPUPsr7cPJ7VH9oSdG6OTZv vAPAThh3fyiy5SMNFhmIRrt36YXw2LydxWiThy+70zfdSDoGQhxeNccwcjAaf8tSrDNZcazSggRd5 5oqGOV0w==; Received: from [187.192.11.120] (port=51864 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.92) (envelope-from ) id 1hwxg4-002Qg0-ID; Sun, 11 Aug 2019 18:55:08 -0500 Date: Sun, 11 Aug 2019 18:55:07 -0500 From: "Gustavo A. R. Silva" To: Mimi Zohar , Dmitry Kasatkin , James Morris , "Serge E. Hallyn" , Thiago Jung Bauermann Cc: linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH][next] ima: ima_modsig: Fix use-after-free bug in ima_read_modsig Message-ID: <20190811235507.GA9587@embeddedor> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.9.4 (2018-02-28) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 187.192.11.120 X-Source-L: No X-Exim-ID: 1hwxg4-002Qg0-ID X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [187.192.11.120]:51864 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 7 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP hdr is being freed and then dereferenced by accessing hdr->pkcs7_msg Fix this by copying the value returned by PTR_ERR(hdr->pkcs7_msg) into automatic variable err for its safe use after freeing hdr. Addresses-Coverity-ID: 1485813 ("Read from pointer after free") Fixes: 39b07096364a ("ima: Implement support for module-style appended signatures") Signed-off-by: Gustavo A. R. Silva Reviewed-by: Gustavo A. R. Silva --- security/integrity/ima/ima_modsig.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/security/integrity/ima/ima_modsig.c b/security/integrity/ima/ima_modsig.c index c412e31d1714..e681d4326145 100644 --- a/security/integrity/ima/ima_modsig.c +++ b/security/integrity/ima/ima_modsig.c @@ -91,8 +91,9 @@ int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len, hdr->pkcs7_msg = pkcs7_parse_message(buf + buf_len, sig_len); if (IS_ERR(hdr->pkcs7_msg)) { + int err = PTR_ERR(hdr->pkcs7_msg); kfree(hdr); - return PTR_ERR(hdr->pkcs7_msg); + return err; } memcpy(hdr->raw_pkcs7, buf + buf_len, sig_len);