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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 B7F3FC2D0DB for ; Mon, 20 Jan 2020 16:25:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E1BD2087E for ; Mon, 20 Jan 2020 16:25:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729146AbgATQZu (ORCPT ); Mon, 20 Jan 2020 11:25:50 -0500 Received: from orbyte.nwl.cc ([151.80.46.58]:60796 "EHLO orbyte.nwl.cc" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726988AbgATQZt (ORCPT ); Mon, 20 Jan 2020 11:25:49 -0500 Received: from localhost ([::1]:45654 helo=tatos) by orbyte.nwl.cc with esmtp (Exim 4.91) (envelope-from ) id 1itZs4-00062L-6X; Mon, 20 Jan 2020 17:25:48 +0100 From: Phil Sutter To: Pablo Neira Ayuso Cc: netfilter-devel@vger.kernel.org Subject: [nft PATCH 2/4] netlink: Fix leaks in netlink_parse_cmp() Date: Mon, 20 Jan 2020 17:25:38 +0100 Message-Id: <20200120162540.9699-3-phil@nwl.cc> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200120162540.9699-1-phil@nwl.cc> References: <20200120162540.9699-1-phil@nwl.cc> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org This fixes several problems at once: * Err path would leak expr 'right' in two places and 'left' in one. * Concat case would leak 'right' by overwriting the pointer. Introduce a temporary variable to hold the new pointer. Fixes: 6377380bc265f ("netlink_delinearize: handle relational and lookup concat expressions") Signed-off-by: Phil Sutter --- src/netlink_delinearize.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/src/netlink_delinearize.c b/src/netlink_delinearize.c index 06a0312b9921a..88dbd5a8ecdf3 100644 --- a/src/netlink_delinearize.c +++ b/src/netlink_delinearize.c @@ -274,7 +274,7 @@ static void netlink_parse_cmp(struct netlink_parse_ctx *ctx, { struct nft_data_delinearize nld; enum nft_registers sreg; - struct expr *expr, *left, *right; + struct expr *expr, *left, *right, *tmp; enum ops op; sreg = netlink_parse_register(nle, NFTNL_EXPR_CMP_SREG); @@ -291,19 +291,26 @@ static void netlink_parse_cmp(struct netlink_parse_ctx *ctx, if (left->len > right->len && expr_basetype(left) != &string_type) { - return netlink_error(ctx, loc, "Relational expression size mismatch"); + netlink_error(ctx, loc, "Relational expression size mismatch"); + goto err_free; } else if (left->len > 0 && left->len < right->len) { expr_free(left); left = netlink_parse_concat_expr(ctx, loc, sreg, right->len); if (left == NULL) - return; - right = netlink_parse_concat_data(ctx, loc, sreg, right->len, right); - if (right == NULL) - return; + goto err_free; + tmp = netlink_parse_concat_data(ctx, loc, sreg, right->len, right); + if (tmp == NULL) + goto err_free; + expr_free(right); + right = tmp; } expr = relational_expr_alloc(loc, op, left, right); ctx->stmt = expr_stmt_alloc(loc, expr); + return; +err_free: + expr_free(left); + expr_free(right); } static void netlink_parse_lookup(struct netlink_parse_ctx *ctx, -- 2.24.1