[NETLINK]: Do precise netlink message allocations where possible

Account for the netlink message header size directly in nlmsg_new()
instead of relying on the caller calculate it correctly.

Replaces error handling of message construction functions when
constructing notifications with bug traps since a failure implies
a bug in calculating the size of the skb.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Thomas Graf
2006-11-10 14:10:15 -08:00
committed by David S. Miller
parent a94f723d59
commit 339bf98ffc
21 changed files with 233 additions and 107 deletions

View File

@@ -2006,6 +2006,20 @@ int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
return ip6_route_add(&cfg);
}
static inline size_t rt6_nlmsg_size(void)
{
return NLMSG_ALIGN(sizeof(struct rtmsg))
+ nla_total_size(16) /* RTA_SRC */
+ nla_total_size(16) /* RTA_DST */
+ nla_total_size(16) /* RTA_GATEWAY */
+ nla_total_size(16) /* RTA_PREFSRC */
+ nla_total_size(4) /* RTA_TABLE */
+ nla_total_size(4) /* RTA_IIF */
+ nla_total_size(4) /* RTA_OIF */
+ nla_total_size(4) /* RTA_PRIORITY */
+ nla_total_size(sizeof(struct rta_cacheinfo));
}
static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
struct in6_addr *dst, struct in6_addr *src,
int iif, int type, u32 pid, u32 seq,
@@ -2200,7 +2214,6 @@ void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
struct sk_buff *skb;
u32 pid = 0, seq = 0;
struct nlmsghdr *nlh = NULL;
int payload = sizeof(struct rtmsg) + 256;
int err = -ENOBUFS;
if (info) {
@@ -2210,15 +2223,13 @@ void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
seq = nlh->nlmsg_seq;
}
skb = nlmsg_new(nlmsg_total_size(payload), gfp_any());
skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
if (skb == NULL)
goto errout;
err = rt6_fill_node(skb, rt, NULL, NULL, 0, event, pid, seq, 0, 0);
if (err < 0) {
kfree_skb(skb);
goto errout;
}
/* failure implies BUG in rt6_nlmsg_size() */
BUG_ON(err < 0);
err = rtnl_notify(skb, pid, RTNLGRP_IPV6_ROUTE, nlh, gfp_any());
errout: