From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 309AF219301; Tue, 8 Apr 2025 11:38:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744112294; cv=none; b=USJpWSH5unAvPfewge75BwZrm2PZwMXI08oDyzPpS4ghSWZ+MzHXxgJ//UEKXgAfiIrNALa2OhlMVgEtGLto47LITB/P6s9Gt/y6Bw0AeNctB5grSpYG1Zpb0iY+btE63sq93OPZULOlTvQFmzcblMaE7M1CbUbZMp5RQkvN7W0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744112294; c=relaxed/simple; bh=VxTiyk6YH1aUhQDxWlG4tSC1kDH9IaPdpklZf3b/MyU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fy07LLWDoMSDUTo1S7CcRVTJYAZ0jXws5HLoErgm1L5vvF0FMibgEGl7lpT0XamSfqiQCLZn1wyYAx/rVlZfHecpAMKPzhR3jdLFjrvXdNa3cHf8J0NXQ7NytRPgUQ5t1njrcaVILYUY5Tpvdd8IbSojPrd50oDfcmXcVT0qyoc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=vlbOP1PP; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="vlbOP1PP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6A68C4CEE5; Tue, 8 Apr 2025 11:38:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744112294; bh=VxTiyk6YH1aUhQDxWlG4tSC1kDH9IaPdpklZf3b/MyU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vlbOP1PPmR0IPUO4dyMD4R0DE2X4T3aEl3Qo59omMZD8fgXZOyCiytr94ureAYZRD AcIqjWpHYj9R40kkEHdnK+EB0O+HyoynJK1QVSWnnAWoS7smtqs/gj3YFQSVtZQeSa QreTCF56HHZEUP+mhuiWuz7ADQNcVGlWADm4BPfY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alexey Kashavkin , Florian Westphal , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 5.15 016/279] netfilter: nft_exthdr: fix offset with ipv4_find_option() Date: Tue, 8 Apr 2025 12:46:39 +0200 Message-ID: <20250408104826.819515614@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250408104826.319283234@linuxfoundation.org> References: <20250408104826.319283234@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexey Kashavkin [ Upstream commit 6edd78af9506bb182518da7f6feebd75655d9a0e ] There is an incorrect calculation in the offset variable which causes the nft_skb_copy_to_reg() function to always return -EFAULT. Adding the start variable is redundant. In the __ip_options_compile() function the correct offset is specified when finding the function. There is no need to add the size of the iphdr structure to the offset. Fixes: dbb5281a1f84 ("netfilter: nf_tables: add support for matching IPv4 options") Signed-off-by: Alexey Kashavkin Reviewed-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/nft_exthdr.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/net/netfilter/nft_exthdr.c b/net/netfilter/nft_exthdr.c index d1dcf5b2e92e1..7c2931e024bb0 100644 --- a/net/netfilter/nft_exthdr.c +++ b/net/netfilter/nft_exthdr.c @@ -85,7 +85,6 @@ static int ipv4_find_option(struct net *net, struct sk_buff *skb, unsigned char optbuf[sizeof(struct ip_options) + 40]; struct ip_options *opt = (struct ip_options *)optbuf; struct iphdr *iph, _iph; - unsigned int start; bool found = false; __be32 info; int optlen; @@ -93,7 +92,6 @@ static int ipv4_find_option(struct net *net, struct sk_buff *skb, iph = skb_header_pointer(skb, 0, sizeof(_iph), &_iph); if (!iph) return -EBADMSG; - start = sizeof(struct iphdr); optlen = iph->ihl * 4 - (int)sizeof(struct iphdr); if (optlen <= 0) @@ -103,7 +101,7 @@ static int ipv4_find_option(struct net *net, struct sk_buff *skb, /* Copy the options since __ip_options_compile() modifies * the options. */ - if (skb_copy_bits(skb, start, opt->__data, optlen)) + if (skb_copy_bits(skb, sizeof(struct iphdr), opt->__data, optlen)) return -EBADMSG; opt->optlen = optlen; @@ -118,18 +116,18 @@ static int ipv4_find_option(struct net *net, struct sk_buff *skb, found = target == IPOPT_SSRR ? opt->is_strictroute : !opt->is_strictroute; if (found) - *offset = opt->srr + start; + *offset = opt->srr; break; case IPOPT_RR: if (!opt->rr) break; - *offset = opt->rr + start; + *offset = opt->rr; found = true; break; case IPOPT_RA: if (!opt->router_alert) break; - *offset = opt->router_alert + start; + *offset = opt->router_alert; found = true; break; default: -- 2.39.5