[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

@ -306,6 +306,22 @@ errout:
return err;
}
static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
struct fib_rule *rule)
{
size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
+ nla_total_size(IFNAMSIZ) /* FRA_IFNAME */
+ nla_total_size(4) /* FRA_PRIORITY */
+ nla_total_size(4) /* FRA_TABLE */
+ nla_total_size(4) /* FRA_FWMARK */
+ nla_total_size(4); /* FRA_FWMASK */
if (ops->nlmsg_payload)
payload += ops->nlmsg_payload(rule);
return payload;
}
static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
u32 pid, u32 seq, int type, int flags,
struct fib_rules_ops *ops)
@ -384,15 +400,13 @@ static void notify_rule_change(int event, struct fib_rule *rule,
struct sk_buff *skb;
int err = -ENOBUFS;
skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
if (skb == NULL)
goto errout;
err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
if (err < 0) {
kfree_skb(skb);
goto errout;
}
/* failure implies BUG in fib_rule_nlmsg_size() */
BUG_ON(err < 0);
err = rtnl_notify(skb, pid, ops->nlgroup, nlh, GFP_KERNEL);
errout: