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 00DEB6FA0 for ; Mon, 16 Jan 2023 17:09:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7B89DC433D2; Mon, 16 Jan 2023 17:09:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1673888992; bh=tkivG05ywDSGTRa5BdLHwBm45SPIWbcqx+hXNqGw/DQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=p4cfJ69CkloMuIgt2l7ajLy3VvAe429+Mqi0sOc9mVCAM7z5cP3sBdLI1qNwSNDDk KOOFUVBZ6dK254qNc3H9Y9/DqCqkzOuJk0lI94mfFprq5haFOI1Fdqlb9kxGhjaGh/ qw69Avq/M4A6ieIUSeu4opa00M29XWJpCyV7Dosw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eelco Chaudron , "David S. Miller" , Sasha Levin Subject: [PATCH 4.14 210/338] openvswitch: Fix flow lookup to use unmasked key Date: Mon, 16 Jan 2023 16:51:23 +0100 Message-Id: <20230116154830.165799593@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230116154820.689115727@linuxfoundation.org> References: <20230116154820.689115727@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Eelco Chaudron [ Upstream commit 68bb10101e6b0a6bb44e9c908ef795fc4af99eae ] The commit mentioned below causes the ovs_flow_tbl_lookup() function to be called with the masked key. However, it's supposed to be called with the unmasked key. This due to the fact that the datapath supports installing wider flows, and OVS relies on this behavior. For example if ipv4(src=1.1.1.1/192.0.0.0, dst=1.1.1.2/192.0.0.0) exists, a wider flow (smaller mask) of ipv4(src=192.1.1.1/128.0.0.0,dst=192.1.1.2/ 128.0.0.0) is allowed to be added. However, if we try to add a wildcard rule, the installation fails: $ ovs-appctl dpctl/add-flow system@myDP "in_port(1),eth_type(0x0800), \ ipv4(src=1.1.1.1/192.0.0.0,dst=1.1.1.2/192.0.0.0,frag=no)" 2 $ ovs-appctl dpctl/add-flow system@myDP "in_port(1),eth_type(0x0800), \ ipv4(src=192.1.1.1/0.0.0.0,dst=49.1.1.2/0.0.0.0,frag=no)" 2 ovs-vswitchd: updating flow table (File exists) The reason is that the key used to determine if the flow is already present in the system uses the original key ANDed with the mask. This results in the IP address not being part of the (miniflow) key, i.e., being substituted with an all-zero value. When doing the actual lookup, this results in the key wrongfully matching the first flow, and therefore the flow does not get installed. This change reverses the commit below, but rather than having the key on the stack, it's allocated. Fixes: 190aa3e77880 ("openvswitch: Fix Frame-size larger than 1024 bytes warning.") Signed-off-by: Eelco Chaudron Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/openvswitch/datapath.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index a57a3755611d..8598bc101244 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -930,6 +930,7 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info) struct sw_flow_mask mask; struct sk_buff *reply; struct datapath *dp; + struct sw_flow_key *key; struct sw_flow_actions *acts; struct sw_flow_match match; u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]); @@ -957,24 +958,26 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info) } /* Extract key. */ - ovs_match_init(&match, &new_flow->key, false, &mask); + key = kzalloc(sizeof(*key), GFP_KERNEL); + if (!key) { + error = -ENOMEM; + goto err_kfree_key; + } + + ovs_match_init(&match, key, false, &mask); error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY], a[OVS_FLOW_ATTR_MASK], log); if (error) goto err_kfree_flow; + ovs_flow_mask_key(&new_flow->key, key, true, &mask); + /* Extract flow identifier. */ error = ovs_nla_get_identifier(&new_flow->id, a[OVS_FLOW_ATTR_UFID], - &new_flow->key, log); + key, log); if (error) goto err_kfree_flow; - /* unmasked key is needed to match when ufid is not used. */ - if (ovs_identifier_is_key(&new_flow->id)) - match.key = new_flow->id.unmasked_key; - - ovs_flow_mask_key(&new_flow->key, &new_flow->key, true, &mask); - /* Validate actions. */ error = ovs_nla_copy_actions(net, a[OVS_FLOW_ATTR_ACTIONS], &new_flow->key, &acts, log); @@ -1001,7 +1004,7 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info) if (ovs_identifier_is_ufid(&new_flow->id)) flow = ovs_flow_tbl_lookup_ufid(&dp->table, &new_flow->id); if (!flow) - flow = ovs_flow_tbl_lookup(&dp->table, &new_flow->key); + flow = ovs_flow_tbl_lookup(&dp->table, key); if (likely(!flow)) { rcu_assign_pointer(new_flow->sf_acts, acts); @@ -1071,6 +1074,8 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info) if (reply) ovs_notify(&dp_flow_genl_family, reply, info); + + kfree(key); return 0; err_unlock_ovs: @@ -1080,6 +1085,8 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info) ovs_nla_free_flow_actions(acts); err_kfree_flow: ovs_flow_free(new_flow, false); +err_kfree_key: + kfree(key); error: return error; } -- 2.35.1