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 B570320B3E; Tue, 23 Apr 2024 21:41:00 +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=1713908460; cv=none; b=nw+tRZ9nK+DFJashSUevxskgRt5ORwZsBd2Yp30qmYezUiJ/HwKhp7FK4TxpvZX7Y7ElLP66DP4mTU5yehSIm8kDpsyBzL64yMHpqmrehVdR2Oml6RItndG6LFVAaLWW24Vx3vqxIn5/Lfe5ybz38tJZEC6UGa5DyMFFkYb3Qdk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713908460; c=relaxed/simple; bh=AruY2WZSZrJdKY3QQphuoK2wRPEtzwuVH7h/XN0yvfw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qkyJkj+SGiwhAckqr351bLaUs5jt7TxXWp/dbO0ZBTCkEwtRXXdXJngcQYGLgEkJlEyG10X4tjA2gFvH5QmkBtxoDG9UW63GoBs4bxbTqr2pevad/AIaNf09L4BSixtjpVy/B4THVzsRHIqzU6uGA54cnwoaIzJy3JRTvSUgDek= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=U/SeQdXP; 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="U/SeQdXP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 348DFC3277B; Tue, 23 Apr 2024 21:41:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1713908460; bh=AruY2WZSZrJdKY3QQphuoK2wRPEtzwuVH7h/XN0yvfw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=U/SeQdXPYZCaFikJBCBX449CKx3sDPW3QhyXYXToobhTPRaqr8JwV3zAwOS0DBggo p8x0BPWgQlSSKmcN9KwwqySSq53rFX6rMoUqIE0aozhqRPavMvBrQuavbEOsmZrzox ckIHEVORNjC+1LxCMyyxBE1lyaHT+XuCTlAARpMw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+b6f07e1c07ef40199081@syzkaller.appspotmail.com, Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 6.8 020/158] netfilter: flowtable: validate pppoe header Date: Tue, 23 Apr 2024 14:37:22 -0700 Message-ID: <20240423213856.519679240@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240423213855.824778126@linuxfoundation.org> References: <20240423213855.824778126@linuxfoundation.org> User-Agent: quilt/0.67 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 6.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pablo Neira Ayuso [ Upstream commit 87b3593bed1868b2d9fe096c01bcdf0ea86cbebf ] Ensure there is sufficient room to access the protocol field of the PPPoe header. Validate it once before the flowtable lookup, then use a helper function to access protocol field. Reported-by: syzbot+b6f07e1c07ef40199081@syzkaller.appspotmail.com Fixes: 72efd585f714 ("netfilter: flowtable: add pppoe support") Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- include/net/netfilter/nf_flow_table.h | 12 +++++++++++- net/netfilter/nf_flow_table_inet.c | 3 ++- net/netfilter/nf_flow_table_ip.c | 8 +++++--- 3 files changed, 18 insertions(+), 5 deletions(-) diff --git a/include/net/netfilter/nf_flow_table.h b/include/net/netfilter/nf_flow_table.h index a763dd327c6ea..9abb7ee40d72f 100644 --- a/include/net/netfilter/nf_flow_table.h +++ b/include/net/netfilter/nf_flow_table.h @@ -336,7 +336,7 @@ int nf_flow_rule_route_ipv6(struct net *net, struct flow_offload *flow, int nf_flow_table_offload_init(void); void nf_flow_table_offload_exit(void); -static inline __be16 nf_flow_pppoe_proto(const struct sk_buff *skb) +static inline __be16 __nf_flow_pppoe_proto(const struct sk_buff *skb) { __be16 proto; @@ -352,6 +352,16 @@ static inline __be16 nf_flow_pppoe_proto(const struct sk_buff *skb) return 0; } +static inline bool nf_flow_pppoe_proto(struct sk_buff *skb, __be16 *inner_proto) +{ + if (!pskb_may_pull(skb, PPPOE_SES_HLEN)) + return false; + + *inner_proto = __nf_flow_pppoe_proto(skb); + + return true; +} + #define NF_FLOW_TABLE_STAT_INC(net, count) __this_cpu_inc((net)->ft.stat->count) #define NF_FLOW_TABLE_STAT_DEC(net, count) __this_cpu_dec((net)->ft.stat->count) #define NF_FLOW_TABLE_STAT_INC_ATOMIC(net, count) \ diff --git a/net/netfilter/nf_flow_table_inet.c b/net/netfilter/nf_flow_table_inet.c index 9505f9d188ff2..6eef15648b7b0 100644 --- a/net/netfilter/nf_flow_table_inet.c +++ b/net/netfilter/nf_flow_table_inet.c @@ -21,7 +21,8 @@ nf_flow_offload_inet_hook(void *priv, struct sk_buff *skb, proto = veth->h_vlan_encapsulated_proto; break; case htons(ETH_P_PPP_SES): - proto = nf_flow_pppoe_proto(skb); + if (!nf_flow_pppoe_proto(skb, &proto)) + return NF_ACCEPT; break; default: proto = skb->protocol; diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c index e45fade764096..9e9e105052dae 100644 --- a/net/netfilter/nf_flow_table_ip.c +++ b/net/netfilter/nf_flow_table_ip.c @@ -273,10 +273,11 @@ static unsigned int nf_flow_xmit_xfrm(struct sk_buff *skb, return NF_STOLEN; } -static bool nf_flow_skb_encap_protocol(const struct sk_buff *skb, __be16 proto, +static bool nf_flow_skb_encap_protocol(struct sk_buff *skb, __be16 proto, u32 *offset) { struct vlan_ethhdr *veth; + __be16 inner_proto; switch (skb->protocol) { case htons(ETH_P_8021Q): @@ -287,7 +288,8 @@ static bool nf_flow_skb_encap_protocol(const struct sk_buff *skb, __be16 proto, } break; case htons(ETH_P_PPP_SES): - if (nf_flow_pppoe_proto(skb) == proto) { + if (nf_flow_pppoe_proto(skb, &inner_proto) && + inner_proto == proto) { *offset += PPPOE_SES_HLEN; return true; } @@ -316,7 +318,7 @@ static void nf_flow_encap_pop(struct sk_buff *skb, skb_reset_network_header(skb); break; case htons(ETH_P_PPP_SES): - skb->protocol = nf_flow_pppoe_proto(skb); + skb->protocol = __nf_flow_pppoe_proto(skb); skb_pull(skb, PPPOE_SES_HLEN); skb_reset_network_header(skb); break; -- 2.43.0