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 CD8E54C6E; Mon, 23 Jun 2025 13:34:06 +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=1750685646; cv=none; b=sJu2mpw0aurFhhFgSCAdOYzRh9Ise+Xc134Zufv+PtGD89Had/Z7JF3J/caaocXXHBkq91XG0nf1dCmwdYlsW9oQ1ljAsnsdVlDnFRRE5fJdTNFhQfSAQ/slmKmXmrVvh3C4mR9+nNFomGhyULX5A/F+A5mp8rooCjc8X5R1lMU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750685646; c=relaxed/simple; bh=3KgiS3tnbDiiZR3oCCyMIbcXUhTBr31Ms1505/kZEPk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FhA2FpHQ10hhBDRQxma12Af01KOKfNsFnsNyyUffy5o8gULpX6iqhBip4GLqVXrK6b1KNJlN0cuCmZsW3awjcfaNrD3D4jp8fH3mZDslP0ziyWh2z8QrLypdyzmjodF2iiw9T/PLi99f3YsraOhU+1kwPdSnBjtELgm98NS2guU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=cV2zJaks; 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="cV2zJaks" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 60EEAC4CEEA; Mon, 23 Jun 2025 13:34:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750685646; bh=3KgiS3tnbDiiZR3oCCyMIbcXUhTBr31Ms1505/kZEPk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cV2zJaksCoapjfgqGHKdG0lWkJiomUhycW+UJ3SsjT/ckDhYf6H14rgYTBmi+Hn5B HFNoPM2zqHFExiz9OVcZTJm8bkFXGxVvQ62djZRI46LjR+y6IsBZfGe/3nUn+kP1kw OShagBWVDlvQY7YTzBUkURcc2iICQ2+BNLIw+2mI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Huajian Yang , Florian Westphal , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 5.15 049/411] netfilter: bridge: Move specific fragmented packet to slow_path instead of dropping it Date: Mon, 23 Jun 2025 15:03:13 +0200 Message-ID: <20250623130634.468714278@linuxfoundation.org> X-Mailer: git-send-email 2.50.0 In-Reply-To: <20250623130632.993849527@linuxfoundation.org> References: <20250623130632.993849527@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev 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: Huajian Yang [ Upstream commit aa04c6f45b9224b949aa35d4fa5f8d0ba07b23d4 ] The config NF_CONNTRACK_BRIDGE will change the bridge forwarding for fragmented packets. The original bridge does not know that it is a fragmented packet and forwards it directly, after NF_CONNTRACK_BRIDGE is enabled, function nf_br_ip_fragment and br_ip6_fragment will check the headroom. In original br_forward, insufficient headroom of skb may indeed exist, but there's still a way to save the skb in the device driver after dev_queue_xmit.So droping the skb will change the original bridge forwarding in some cases. Fixes: 3c171f496ef5 ("netfilter: bridge: add connection tracking system") Signed-off-by: Huajian Yang Reviewed-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/bridge/netfilter/nf_conntrack_bridge.c | 12 ++++++------ net/ipv6/netfilter.c | 12 ++++++------ 2 files changed, 12 insertions(+), 12 deletions(-) diff --git a/net/bridge/netfilter/nf_conntrack_bridge.c b/net/bridge/netfilter/nf_conntrack_bridge.c index fbdb1ad448c3a..c63ad63db25ed 100644 --- a/net/bridge/netfilter/nf_conntrack_bridge.c +++ b/net/bridge/netfilter/nf_conntrack_bridge.c @@ -59,19 +59,19 @@ static int nf_br_ip_fragment(struct net *net, struct sock *sk, struct ip_fraglist_iter iter; struct sk_buff *frag; - if (first_len - hlen > mtu || - skb_headroom(skb) < ll_rs) + if (first_len - hlen > mtu) goto blackhole; - if (skb_cloned(skb)) + if (skb_cloned(skb) || + skb_headroom(skb) < ll_rs) goto slow_path; skb_walk_frags(skb, frag) { - if (frag->len > mtu || - skb_headroom(frag) < hlen + ll_rs) + if (frag->len > mtu) goto blackhole; - if (skb_shared(frag)) + if (skb_shared(frag) || + skb_headroom(frag) < hlen + ll_rs) goto slow_path; } diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c index 118e834e91902..064163b41cbf6 100644 --- a/net/ipv6/netfilter.c +++ b/net/ipv6/netfilter.c @@ -163,20 +163,20 @@ int br_ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, struct ip6_fraglist_iter iter; struct sk_buff *frag2; - if (first_len - hlen > mtu || - skb_headroom(skb) < (hroom + sizeof(struct frag_hdr))) + if (first_len - hlen > mtu) goto blackhole; - if (skb_cloned(skb)) + if (skb_cloned(skb) || + skb_headroom(skb) < (hroom + sizeof(struct frag_hdr))) goto slow_path; skb_walk_frags(skb, frag2) { - if (frag2->len > mtu || - skb_headroom(frag2) < (hlen + hroom + sizeof(struct frag_hdr))) + if (frag2->len > mtu) goto blackhole; /* Partially cloned skb? */ - if (skb_shared(frag2)) + if (skb_shared(frag2) || + skb_headroom(frag2) < (hlen + hroom + sizeof(struct frag_hdr))) goto slow_path; } -- 2.39.5