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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33E04C19F2D for ; Tue, 9 Aug 2022 18:04:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344537AbiHISEn (ORCPT ); Tue, 9 Aug 2022 14:04:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34710 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344532AbiHISDk (ORCPT ); Tue, 9 Aug 2022 14:03:40 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7391D275E9; Tue, 9 Aug 2022 11:02:05 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 5575261012; Tue, 9 Aug 2022 18:02:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 92CC4C433D7; Tue, 9 Aug 2022 18:02:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660068125; bh=Rk+9dz2pOvI01ubf5O3Bj2SDe/szN9eGPeK/+iP1tN0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nEz2DYwEFp+R74lHD7c82fRuS+8aLSL6BoAT0EGSm6rP1+UQ1ZFsUOTPaajp7P5iJ U3O81yDnFTJk6qWWg3kaScAHJox1QNwpIGGJ9hZiXzOCAEJ5e4SuzAaujj/SF2eMpj A2WxtC9/E0f1IyBVISQFVkEzmmbu+HetxWkfGEX8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Domingo Dirutigliano , Florian Westphal , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 4.19 23/32] netfilter: nf_queue: do not allow packet truncation below transport header offset Date: Tue, 9 Aug 2022 20:00:14 +0200 Message-Id: <20220809175513.816660088@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220809175513.082573955@linuxfoundation.org> References: <20220809175513.082573955@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Florian Westphal [ Upstream commit 99a63d36cb3ed5ca3aa6fcb64cffbeaf3b0fb164 ] Domingo Dirutigliano and Nicola Guerrera report kernel panic when sending nf_queue verdict with 1-byte nfta_payload attribute. The IP/IPv6 stack pulls the IP(v6) header from the packet after the input hook. If user truncates the packet below the header size, this skb_pull() will result in a malformed skb (skb->len < 0). Fixes: 7af4cc3fa158 ("[NETFILTER]: Add "nfnetlink_queue" netfilter queue handler over nfnetlink") Reported-by: Domingo Dirutigliano Signed-off-by: Florian Westphal Reviewed-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/nfnetlink_queue.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c index a5aff2834bd6..cd496b074a71 100644 --- a/net/netfilter/nfnetlink_queue.c +++ b/net/netfilter/nfnetlink_queue.c @@ -850,11 +850,16 @@ nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum) } static int -nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e, int diff) +nfqnl_mangle(void *data, unsigned int data_len, struct nf_queue_entry *e, int diff) { struct sk_buff *nskb; if (diff < 0) { + unsigned int min_len = skb_transport_offset(e->skb); + + if (data_len < min_len) + return -EINVAL; + if (pskb_trim(e->skb, data_len)) return -ENOMEM; } else if (diff > 0) { -- 2.35.1