From b1974ed05ea90264d534a200e8a13932ad55f8b8 Mon Sep 17 00:00:00 2001 From: "Arad, Ronen" Date: Mon, 19 Oct 2015 09:23:28 -0700 Subject: [PATCH] netlink: Rightsize IFLA_AF_SPEC size calculation if_nlmsg_size() overestimates the minimum allocation size of netlink dump request (when called from rtnl_calcit()) or the size of the message (when called from rtnl_getlink()). This is because ext_filter_mask is not supported by rtnl_link_get_af_size() and rtnl_link_get_size(). The over-estimation is significant when at least one netdev has many VLANs configured (8 bytes for each configured VLAN). This patch-set "rightsizes" the protocol specific attribute size calculation by propagating ext_filter_mask to rtnl_link_get_af_size() and adding this a argument to get_link_af_size op in rtnl_af_ops. Bridge module already used filtering aware sizing for notifications. br_get_link_af_size_filtered() is consistent with the modified get_link_af_size op so it replaces br_get_link_af_size() in br_af_ops. br_get_link_af_size() becomes unused and thus removed. Signed-off-by: Ronen Arad Acked-by: Sridhar Samudrala Signed-off-by: David S. Miller --- include/net/rtnetlink.h | 3 ++- net/bridge/br_netlink.c | 21 +-------------------- net/core/rtnetlink.c | 8 ++++---- net/ipv4/devinet.c | 4 ++-- net/ipv6/addrconf.c | 3 ++- 5 files changed, 11 insertions(+), 28 deletions(-) diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h index aff6ceb891a9..2f87c1ba13de 100644 --- a/include/net/rtnetlink.h +++ b/include/net/rtnetlink.h @@ -124,7 +124,8 @@ struct rtnl_af_ops { int (*fill_link_af)(struct sk_buff *skb, const struct net_device *dev, u32 ext_filter_mask); - size_t (*get_link_af_size)(const struct net_device *dev); + size_t (*get_link_af_size)(const struct net_device *dev, + u32 ext_filter_mask); int (*validate_link_af)(const struct net_device *dev, const struct nlattr *attr); diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c index 94b4de8c4646..40197ff8918a 100644 --- a/net/bridge/br_netlink.c +++ b/net/bridge/br_netlink.c @@ -1214,29 +1214,10 @@ static int br_fill_info(struct sk_buff *skb, const struct net_device *brdev) return 0; } -static size_t br_get_link_af_size(const struct net_device *dev) -{ - struct net_bridge_port *p; - struct net_bridge *br; - int num_vlans = 0; - - if (br_port_exists(dev)) { - p = br_port_get_rtnl(dev); - num_vlans = br_get_num_vlan_infos(nbp_vlan_group(p), - RTEXT_FILTER_BRVLAN); - } else if (dev->priv_flags & IFF_EBRIDGE) { - br = netdev_priv(dev); - num_vlans = br_get_num_vlan_infos(br_vlan_group(br), - RTEXT_FILTER_BRVLAN); - } - - /* Each VLAN is returned in bridge_vlan_info along with flags */ - return num_vlans * nla_total_size(sizeof(struct bridge_vlan_info)); -} static struct rtnl_af_ops br_af_ops __read_mostly = { .family = AF_BRIDGE, - .get_link_af_size = br_get_link_af_size, + .get_link_af_size = br_get_link_af_size_filtered, }; struct rtnl_link_ops br_link_ops __read_mostly = { diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 24775953fa68..7c78b5aca944 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -497,7 +497,8 @@ void rtnl_af_unregister(struct rtnl_af_ops *ops) } EXPORT_SYMBOL_GPL(rtnl_af_unregister); -static size_t rtnl_link_get_af_size(const struct net_device *dev) +static size_t rtnl_link_get_af_size(const struct net_device *dev, + u32 ext_filter_mask) { struct rtnl_af_ops *af_ops; size_t size; @@ -509,7 +510,7 @@ static size_t rtnl_link_get_af_size(const struct net_device *dev) if (af_ops->get_link_af_size) { /* AF_* + nested data */ size += nla_total_size(sizeof(struct nlattr)) + - af_ops->get_link_af_size(dev); + af_ops->get_link_af_size(dev, ext_filter_mask); } } @@ -900,7 +901,7 @@ static noinline size_t if_nlmsg_size(const struct net_device *dev, + rtnl_vfinfo_size(dev, ext_filter_mask) /* IFLA_VFINFO_LIST */ + rtnl_port_size(dev, ext_filter_mask) /* IFLA_VF_PORTS + IFLA_PORT_SELF */ + rtnl_link_get_size(dev) /* IFLA_LINKINFO */ - + rtnl_link_get_af_size(dev) /* IFLA_AF_SPEC */ + + rtnl_link_get_af_size(dev, ext_filter_mask) /* IFLA_AF_SPEC */ + nla_total_size(MAX_PHYS_ITEM_ID_LEN) /* IFLA_PHYS_PORT_ID */ + nla_total_size(MAX_PHYS_ITEM_ID_LEN) /* IFLA_PHYS_SWITCH_ID */ + nla_total_size(1); /* IFLA_PROTO_DOWN */ @@ -3443,4 +3444,3 @@ void __init rtnetlink_init(void) rtnl_register(PF_BRIDGE, RTM_DELLINK, rtnl_bridge_dellink, NULL, NULL); rtnl_register(PF_BRIDGE, RTM_SETLINK, rtnl_bridge_setlink, NULL, NULL); } - diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 735008472844..cebd9d31e65a 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -1644,7 +1644,8 @@ errout: rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err); } -static size_t inet_get_link_af_size(const struct net_device *dev) +static size_t inet_get_link_af_size(const struct net_device *dev, + u32 ext_filter_mask) { struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr); @@ -2398,4 +2399,3 @@ void __init devinet_init(void) rtnl_register(PF_INET, RTM_GETNETCONF, inet_netconf_get_devconf, inet_netconf_dump_devconf, NULL); } - diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index d135350495e8..d0c685cdc345 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -4788,7 +4788,8 @@ nla_put_failure: return -EMSGSIZE; } -static size_t inet6_get_link_af_size(const struct net_device *dev) +static size_t inet6_get_link_af_size(const struct net_device *dev, + u32 ext_filter_mask) { if (!__in6_dev_get(dev)) return 0; -- 2.20.1