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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 0D672C76188 for ; Sat, 20 Jul 2019 12:24:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C6BEC20873 for ; Sat, 20 Jul 2019 12:24:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=umn.edu header.i=@umn.edu header.b="VsAKaUY5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728225AbfGTMXp (ORCPT ); Sat, 20 Jul 2019 08:23:45 -0400 Received: from mta-p5.oit.umn.edu ([134.84.196.205]:57214 "EHLO mta-p5.oit.umn.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728212AbfGTMXo (ORCPT ); Sat, 20 Jul 2019 08:23:44 -0400 Received: from localhost (unknown [127.0.0.1]) by mta-p5.oit.umn.edu (Postfix) with ESMTP id 10750D83 for ; Sat, 20 Jul 2019 12:23:43 +0000 (UTC) X-Virus-Scanned: amavisd-new at umn.edu Received: from mta-p5.oit.umn.edu ([127.0.0.1]) by localhost (mta-p5.oit.umn.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 7vm2i2yM4bCZ for ; Sat, 20 Jul 2019 07:23:42 -0500 (CDT) Received: from mail-io1-f71.google.com (mail-io1-f71.google.com [209.85.166.71]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mta-p5.oit.umn.edu (Postfix) with ESMTPS id D84CED86 for ; Sat, 20 Jul 2019 07:23:42 -0500 (CDT) Received: by mail-io1-f71.google.com with SMTP id e20so37467046ioe.12 for ; Sat, 20 Jul 2019 05:23:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=umn.edu; s=google; h=from:to:cc:subject:date:message-id; bh=K+9BHnE6RbUTOFhStcy8LrNMOZBD7Jm9/NExEpRtGTs=; b=VsAKaUY5H8pRtOL9M2UvY9iZeZDLaYKRfFF0N8a+Ayc6PHMdqmm/9LShwhaw19OENE pxtbM5Fx5DUA1WzHR5dxLHVeAKGy9wKZXYgRBawbE8gT60iqJsAjGCOPSjBdSDDgFxvu b7Wr0bcGk88XngcmuNvn83WoG1nUCpjjQaU9cJI+MIRtg86w26V7jxttyupJtMxWd/HB ZNw/Rn624IVLdtvABLf7EWYHrhdx7u+JpOfG34xrmKCHBbNWQawqc/DwOrZRcYdi1DQ/ 3tvSHgoFfGyPCW6CymV+IYbxh4sDtLrW7kVl2JQZ6QC8HV0+Ih1vS9KCl1OiZvVwOR6c aJ1Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=K+9BHnE6RbUTOFhStcy8LrNMOZBD7Jm9/NExEpRtGTs=; b=gqrHAGLPIXYqSjOXeiGLfUUa5D3p3uRM6tTSm10iS1khNetiyGpcytoQtVnB5pSDyT pD1VGwC4GKQFYSs0FUxDCVfxsbsTPR6YlxpLGD7Yx/0kfGSjD/NerQhh9ICfPVMpXDhn zt3V1NXAkJIU7JYLRDFbUtS8rUA/up8R/w5r92p6ikUwXQL7QehikcrsX0Sfsbg7iEIu +NEk0D2b3aF4dkQ1kDXdPgoaiIyxXv5VoEE9WeU6/ND8jgaFaWZxnQk46EueiRxgKyjX EmcrsaUWUFNzFU93jcqgYj7lffq6d0woDxLOZFwPzrq+JKycs43XrmFXL08FxEus1KOZ uqTQ== X-Gm-Message-State: APjAAAVUjYdb4IERBSPTFVbF+C9/LPjc2nj6JvXPaak64ihMKVF3NeW5 nMSASacVhncIytfuwgUu3ehoZqt4ABARMYrOYLwe1/eM+SIEWyxClzWvQEl8WLi1TDwS74SZHiQ NopbTwGjXEClhoMwdGa5znbL8Q26n X-Received: by 2002:a6b:b206:: with SMTP id b6mr58517918iof.286.1563625422515; Sat, 20 Jul 2019 05:23:42 -0700 (PDT) X-Google-Smtp-Source: APXvYqxIvZ8x2BA1J9vY8UGimtCbB808vFCxS2Rq0GnEylvdPLpsmWAHPUhim/AqK6Ko3OIPJUTULA== X-Received: by 2002:a6b:b206:: with SMTP id b6mr58517902iof.286.1563625422367; Sat, 20 Jul 2019 05:23:42 -0700 (PDT) Received: from BlueSky.hil-mspphdt.msp.wayport.net ([107.17.71.65]) by smtp.gmail.com with ESMTPSA id m10sm58326660ioj.75.2019.07.20.05.23.40 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sat, 20 Jul 2019 05:23:41 -0700 (PDT) From: Wenwen Wang To: Wenwen Wang Cc: Pablo Neira Ayuso , Jozsef Kadlecsik , Florian Westphal , Roopa Prabhu , Nikolay Aleksandrov , "David S. Miller" , netfilter-devel@vger.kernel.org (open list:NETFILTER), coreteam@netfilter.org (open list:NETFILTER), bridge@lists.linux-foundation.org (moderated list:ETHERNET BRIDGE), netdev@vger.kernel.org (open list:ETHERNET BRIDGE), linux-kernel@vger.kernel.org (open list) Subject: [PATCH] netfilter: ebtables: compat: fix a memory leak bug Date: Sat, 20 Jul 2019 07:22:45 -0500 Message-Id: <1563625366-3602-1-git-send-email-wang6495@umn.edu> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wenwen Wang In compat_do_replace(), a temporary buffer is allocated through vmalloc() to hold entries copied from the user space. The buffer address is firstly saved to 'newinfo->entries', and later on assigned to 'entries_tmp'. Then the entries in this temporary buffer is copied to the internal kernel structure through compat_copy_entries(). If this copy process fails, compat_do_replace() should be terminated. However, the allocated temporary buffer is not freed on this path, leading to a memory leak. To fix the bug, free the buffer before returning from compat_do_replace(). Signed-off-by: Wenwen Wang --- net/bridge/netfilter/ebtables.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index 963dfdc..fd84b48e 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -2261,8 +2261,10 @@ static int compat_do_replace(struct net *net, void __user *user, state.buf_kern_len = size64; ret = compat_copy_entries(entries_tmp, tmp.entries_size, &state); - if (WARN_ON(ret < 0)) + if (WARN_ON(ret < 0)) { + vfree(entries_tmp); goto out_unlock; + } vfree(entries_tmp); tmp.entries_size = size64; -- 2.7.4