From b87cec3814ccc7f6afb0a1378ee7e5110d07cdd3 Mon Sep 17 00:00:00 2001 From: Jarno Rajahalme Date: Thu, 9 Feb 2017 11:21:56 -0800 Subject: [PATCH] openvswitch: Simplify labels length logic. Since 23014011ba42 ("netfilter: conntrack: support a fixed size of 128 distinct labels"), the size of conntrack labels extension has fixed to 128 bits, so we do not need to check for labels sizes shorter than 128 at run-time. This patch simplifies labels length logic accordingly, but allows the conntrack labels size to be increased in the future without breaking the build. In the event of conntrack labels increasing in size OVS would still be able to deal with the 128 first label bits. Suggested-by: Joe Stringer Signed-off-by: Jarno Rajahalme Acked-by: Pravin B Shelar Acked-by: Joe Stringer Signed-off-by: David S. Miller --- net/openvswitch/conntrack.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c index f23934ccce20..fe2a410ce70a 100644 --- a/net/openvswitch/conntrack.c +++ b/net/openvswitch/conntrack.c @@ -129,22 +129,20 @@ static u32 ovs_ct_get_mark(const struct nf_conn *ct) #endif } +/* Guard against conntrack labels max size shrinking below 128 bits. */ +#if NF_CT_LABELS_MAX_SIZE < 16 +#error NF_CT_LABELS_MAX_SIZE must be at least 16 bytes +#endif + static void ovs_ct_get_labels(const struct nf_conn *ct, struct ovs_key_ct_labels *labels) { struct nf_conn_labels *cl = ct ? nf_ct_labels_find(ct) : NULL; - if (cl) { - size_t len = sizeof(cl->bits); - - if (len > OVS_CT_LABELS_LEN) - len = OVS_CT_LABELS_LEN; - else if (len < OVS_CT_LABELS_LEN) - memset(labels, 0, OVS_CT_LABELS_LEN); - memcpy(labels, cl->bits, len); - } else { + if (cl) + memcpy(labels, cl->bits, OVS_CT_LABELS_LEN); + else memset(labels, 0, OVS_CT_LABELS_LEN); - } } static void __ovs_ct_update_key(struct sw_flow_key *key, u8 state, @@ -274,7 +272,7 @@ static int ovs_ct_set_labels(struct sk_buff *skb, struct sw_flow_key *key, nf_ct_labels_ext_add(ct); cl = nf_ct_labels_find(ct); } - if (!cl || sizeof(cl->bits) < OVS_CT_LABELS_LEN) + if (!cl) return -ENOSPC; if (nf_ct_is_confirmed(ct)) { -- 2.20.1