From patchwork Tue Sep 30 17:35:46 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pablo Neira Ayuso X-Patchwork-Id: 395053 X-Patchwork-Delegate: pablo@netfilter.org Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 2A61C1400A8 for ; Wed, 1 Oct 2014 03:34:44 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751904AbaI3Ren (ORCPT ); Tue, 30 Sep 2014 13:34:43 -0400 Received: from mail.us.es ([193.147.175.20]:53306 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751636AbaI3Ren (ORCPT ); Tue, 30 Sep 2014 13:34:43 -0400 Received: (qmail 16320 invoked from network); 30 Sep 2014 19:34:41 +0200 Received: from unknown (HELO us.es) (192.168.2.15) by us.es with SMTP; 30 Sep 2014 19:34:41 +0200 Received: (qmail 11351 invoked by uid 507); 30 Sep 2014 17:34:41 -0000 X-Qmail-Scanner-Diagnostics: from 127.0.0.1 by antivirus5 (envelope-from , uid 501) with qmail-scanner-2.10 (clamdscan: 0.98.4/19455. spamassassin: 3.3.2. Clear:RC:1(127.0.0.1):SA:0(-99.6/7.5):. Processed in 5.666475 secs); 30 Sep 2014 17:34:41 -0000 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on antivirus5 X-Spam-Level: X-Spam-Status: No, score=-99.6 required=7.5 tests=BAYES_50,RCVD_IN_BRBL, RCVD_IN_BRBL_LASTEXT,RCVD_IN_PBL,RCVD_IN_RP_RNBL,RCVD_IN_SORBS_DUL, RDNS_DYNAMIC, SMTPAUTH_US, USER_IN_WHITELIST autolearn=disabled version=3.3.2 X-Spam-ASN: AS12715 87.221.0.0/16 X-Envelope-From: pablo@netfilter.org Received: from unknown (HELO antivirus5) (127.0.0.1) by us.es with SMTP; 30 Sep 2014 17:34:36 -0000 Received: from 192.168.1.13 (192.168.1.13) by antivirus5 (F-Secure/fsigk_smtp/412/antivirus5); Tue, 30 Sep 2014 19:34:36 +0200 (CEST) X-Virus-Status: clean(F-Secure/fsigk_smtp/412/antivirus5) Received: (qmail 29008 invoked from network); 30 Sep 2014 19:34:36 +0200 Received: from 152.88.221.87.dynamic.jazztel.es (HELO localhost.localdomain) (pneira@us.es@87.221.88.152) by mail.us.es with SMTP; 30 Sep 2014 19:34:36 +0200 From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Subject: [PATCH iptables-compat 2/2] iptables-compat: fix use after free in the batch send path Date: Tue, 30 Sep 2014 19:35:46 +0200 Message-Id: <1412098546-8952-2-git-send-email-pablo@netfilter.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1412098546-8952-1-git-send-email-pablo@netfilter.org> References: <1412098546-8952-1-git-send-email-pablo@netfilter.org> Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org Release the batch pages once they have been sent via sendmsg(). Signed-off-by: Pablo Neira Ayuso --- iptables/nft.c | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-) diff --git a/iptables/nft.c b/iptables/nft.c index 8c91e99..a4cea22 100644 --- a/iptables/nft.c +++ b/iptables/nft.c @@ -142,6 +142,18 @@ static void mnl_nft_set_sndbuffer(const struct mnl_socket *nl) nlbuffsiz = newbuffsiz; } +static void mnl_nft_batch_reset(void) +{ + struct batch_page *batch_page, *next; + + list_for_each_entry_safe(batch_page, next, &batch_page_list, head) { + list_del(&batch_page->head); + free(batch_page->batch); + free(batch_page); + batch_num_pages--; + } +} + static ssize_t mnl_nft_socket_sendmsg(const struct mnl_socket *nl) { static const struct sockaddr_nl snl = { @@ -154,12 +166,12 @@ static ssize_t mnl_nft_socket_sendmsg(const struct mnl_socket *nl) .msg_iov = iov, .msg_iovlen = batch_num_pages, }; - struct batch_page *batch_page, *next; - int i = 0; + struct batch_page *batch_page; + int i = 0, ret; mnl_nft_set_sndbuffer(nl); - list_for_each_entry_safe(batch_page, next, &batch_page_list, head) { + list_for_each_entry(batch_page, &batch_page_list, head) { iov[i].iov_base = mnl_nlmsg_batch_head(batch_page->batch); iov[i].iov_len = mnl_nlmsg_batch_size(batch_page->batch); i++; @@ -169,13 +181,12 @@ static ssize_t mnl_nft_socket_sendmsg(const struct mnl_socket *nl) mnl_nlmsg_batch_size(batch_page->batch), sizeof(struct nfgenmsg)); #endif - list_del(&batch_page->head); - free(batch_page->batch); - free(batch_page); - batch_num_pages--; } - return sendmsg(mnl_socket_get_fd(nl), &msg, 0); + ret = sendmsg(mnl_socket_get_fd(nl), &msg, 0); + mnl_nft_batch_reset(); + + return ret; } static int cb_err(const struct nlmsghdr *nlh, void *data)