Reduce size of br_input_skb_cb from 24 to 16 bytes by using bitfield for those values that can only be 0 or 1. igmp is the igmp type value, so it needs to be at least u8. Furthermore, the bridge currently relies on step-by-step initialization of br_input_skb_cb fields as the skb passes through the stack. Explicitly zero out the bridge input cb instead, this avoids having to review/validate that no BR_INPUT_SKB_CB(skb)->foo test can see a 'random' value from previous protocol cb. AFAICS all current fields are always set up before they are read again, so this is not a bug fix. Cc: Roopa Prabhu <roopa@xxxxxxxxxxxxxxxxxxx> Cc: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Florian Westphal <fw@xxxxxxxxx> --- net/bridge/br_arp_nd_proxy.c | 18 +++++++++--------- net/bridge/br_input.c | 2 ++ net/bridge/br_private.h | 12 +++++------- 3 files changed, 16 insertions(+), 16 deletions(-) diff --git a/net/bridge/br_arp_nd_proxy.c b/net/bridge/br_arp_nd_proxy.c index 724b474ade54..15116752365a 100644 --- a/net/bridge/br_arp_nd_proxy.c +++ b/net/bridge/br_arp_nd_proxy.c @@ -131,7 +131,7 @@ void br_do_proxy_suppress_arp(struct sk_buff *skb, struct net_bridge *br, u8 *arpptr, *sha; __be32 sip, tip; - BR_INPUT_SKB_CB(skb)->proxyarp_replied = false; + BR_INPUT_SKB_CB(skb)->proxyarp_replied = 0; if ((dev->flags & IFF_NOARP) || !pskb_may_pull(skb, arp_hdr_len(dev))) @@ -161,7 +161,7 @@ void br_do_proxy_suppress_arp(struct sk_buff *skb, struct net_bridge *br, return; if (ipv4_is_zeronet(sip) || sip == tip) { /* prevent flooding to neigh suppress ports */ - BR_INPUT_SKB_CB(skb)->proxyarp_replied = true; + BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; return; } } @@ -181,7 +181,7 @@ void br_do_proxy_suppress_arp(struct sk_buff *skb, struct net_bridge *br, /* its our local ip, so don't proxy reply * and don't forward to neigh suppress ports */ - BR_INPUT_SKB_CB(skb)->proxyarp_replied = true; + BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; return; } @@ -217,7 +217,7 @@ void br_do_proxy_suppress_arp(struct sk_buff *skb, struct net_bridge *br, */ if (replied || br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED)) - BR_INPUT_SKB_CB(skb)->proxyarp_replied = true; + BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; } neigh_release(n); @@ -393,7 +393,7 @@ void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br, struct ipv6hdr *iphdr; struct neighbour *n; - BR_INPUT_SKB_CB(skb)->proxyarp_replied = false; + BR_INPUT_SKB_CB(skb)->proxyarp_replied = 0; if (p && (p->flags & BR_NEIGH_SUPPRESS)) return; @@ -401,7 +401,7 @@ void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br, if (msg->icmph.icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT && !msg->icmph.icmp6_solicited) { /* prevent flooding to neigh suppress ports */ - BR_INPUT_SKB_CB(skb)->proxyarp_replied = true; + BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; return; } @@ -414,7 +414,7 @@ void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br, if (ipv6_addr_any(saddr) || !ipv6_addr_cmp(saddr, daddr)) { /* prevent flooding to neigh suppress ports */ - BR_INPUT_SKB_CB(skb)->proxyarp_replied = true; + BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; return; } @@ -432,7 +432,7 @@ void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br, /* its our own ip, so don't proxy reply * and don't forward to arp suppress ports */ - BR_INPUT_SKB_CB(skb)->proxyarp_replied = true; + BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; return; } @@ -465,7 +465,7 @@ void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br, */ if (replied || br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED)) - BR_INPUT_SKB_CB(skb)->proxyarp_replied = true; + BR_INPUT_SKB_CB(skb)->proxyarp_replied = 1; } neigh_release(n); } diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c index 5ea7e56119c1..e2f93e5c72da 100644 --- a/net/bridge/br_input.c +++ b/net/bridge/br_input.c @@ -227,6 +227,8 @@ rx_handler_result_t br_handle_frame(struct sk_buff **pskb) if (!skb) return RX_HANDLER_CONSUMED; + memset(skb->cb, 0, sizeof(struct br_input_skb_cb)); + p = br_port_get_rcu(skb->dev); if (p->flags & BR_VLAN_TUNNEL) { if (br_handle_ingress_vlan_tunnel(skb, p, diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 7946aa3b6e09..e7110a6e2b7e 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -425,15 +425,13 @@ struct br_input_skb_cb { struct net_device *brdev; #ifdef CONFIG_BRIDGE_IGMP_SNOOPING - int igmp; - int mrouters_only; + u8 igmp; + u8 mrouters_only:1; #endif - - bool proxyarp_replied; - bool src_port_isolated; - + u8 proxyarp_replied:1; + u8 src_port_isolated:1; #ifdef CONFIG_BRIDGE_VLAN_FILTERING - bool vlan_filtered; + u8 vlan_filtered:1; #endif #ifdef CONFIG_NET_SWITCHDEV -- 2.21.0