diff options
| author | Thomas Graf <tgraf@suug.ch> | 2006-11-10 14:10:15 -0800 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2006-12-02 21:22:11 -0800 |
| commit | 339bf98ffc6a8d8eb16fc532ac57ffbced2f8a68 (patch) | |
| tree | 499ad948863d2753ca10283dcf006ad28954538e /net/decnet | |
| parent | a94f723d595ee085f81b1788d18e031af7eeba91 (diff) | |
| download | op-kernel-dev-339bf98ffc6a8d8eb16fc532ac57ffbced2f8a68.zip op-kernel-dev-339bf98ffc6a8d8eb16fc532ac57ffbced2f8a68.tar.gz | |
[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>
Diffstat (limited to 'net/decnet')
| -rw-r--r-- | net/decnet/dn_rules.c | 6 | ||||
| -rw-r--r-- | net/decnet/dn_table.c | 34 |
2 files changed, 35 insertions, 5 deletions
diff --git a/net/decnet/dn_rules.c b/net/decnet/dn_rules.c index e32d0c3..b7dfd04 100644 --- a/net/decnet/dn_rules.c +++ b/net/decnet/dn_rules.c @@ -241,6 +241,12 @@ static u32 dn_fib_rule_default_pref(void) return 0; } +static size_t dn_fib_rule_nlmsg_payload(struct fib_rule *rule) +{ + return nla_total_size(2) /* dst */ + + nla_total_size(2); /* src */ +} + int dn_fib_dump_rules(struct sk_buff *skb, struct netlink_callback *cb) { return fib_rules_dump(skb, cb, AF_DECnet); diff --git a/net/decnet/dn_table.c b/net/decnet/dn_table.c index 317904b..e74b744 100644 --- a/net/decnet/dn_table.c +++ b/net/decnet/dn_table.c @@ -263,6 +263,32 @@ static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct dn_kern return 0; } +static inline size_t dn_fib_nlmsg_size(struct dn_fib_info *fi) +{ + size_t payload = NLMSG_ALIGN(struct rtmsg) + + nla_total_size(4) /* RTA_TABLE */ + + nla_total_size(2) /* RTA_DST */ + + nla_total_size(4); /* RTA_PRIORITY */ + + /* space for nested metrics */ + payload += nla_total_size((RTAX_MAX * nla_total_size(4))); + + if (fi->fib_nhs) { + /* Also handles the special case fib_nhs == 1 */ + + /* each nexthop is packed in an attribute */ + size_t nhsize = nla_total_size(sizeof(struct rtnexthop)); + + /* may contain a gateway attribute */ + nhsize += nla_total_size(4); + + /* all nexthops are packed in a nested attribute */ + payload += nla_total_size(fi->fib_nhs * nhsize); + } + + return payload; +} + static int dn_fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event, u32 tb_id, u8 type, u8 scope, void *dst, int dst_len, struct dn_fib_info *fi, unsigned int flags) @@ -335,17 +361,15 @@ static void dn_rtmsg_fib(int event, struct dn_fib_node *f, int z, u32 tb_id, u32 pid = req ? req->pid : 0; int err = -ENOBUFS; - skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); + skb = nlmsg_new(dn_fib_nlmsg_size(DN_FIB_INFO(f), GFP_KERNEL)); if (skb == NULL) goto errout; err = dn_fib_dump_info(skb, pid, nlh->nlmsg_seq, event, tb_id, f->fn_type, f->fn_scope, &f->fn_key, z, DN_FIB_INFO(f), 0); - if (err < 0) { - kfree_skb(skb); - goto errout; - } + /* failure implies BUG in dn_fib_nlmsg_size() */ + BUG_ON(err < 0); err = rtnl_notify(skb, pid, RTNLGRP_DECnet_ROUTE, nlh, GFP_KERNEL); errout: |
