tcp: md5: use sock_kmalloc() to limit md5 keys
There is no limit on number of MD5 keys an application can attach to a
tcp socket.
This patch adds a per tcp socket limit based
on /proc/sys/net/core/optmem_max
With current default optmem_max values, this allows about 150 keys on
64bit arches, and 88 keys on 32bit arches.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 1d5fd82..da5d322 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -943,11 +943,11 @@
tp->md5sig_info = md5sig;
}
- key = kmalloc(sizeof(*key), gfp);
+ key = sock_kmalloc(sk, sizeof(*key), gfp);
if (!key)
return -ENOMEM;
if (hlist_empty(&md5sig->head) && !tcp_alloc_md5sig_pool(sk)) {
- kfree(key);
+ sock_kfree_s(sk, key, sizeof(*key));
return -ENOMEM;
}
@@ -971,6 +971,7 @@
if (!key)
return -ENOENT;
hlist_del_rcu(&key->node);
+ atomic_sub(sizeof(*key), &sk->sk_omem_alloc);
kfree_rcu(key, rcu);
if (hlist_empty(&tp->md5sig_info->head))
tcp_free_md5sig_pool();
@@ -988,6 +989,7 @@
tcp_free_md5sig_pool();
hlist_for_each_entry_safe(key, pos, n, &tp->md5sig_info->head, node) {
hlist_del_rcu(&key->node);
+ atomic_sub(sizeof(*key), &sk->sk_omem_alloc);
kfree_rcu(key, rcu);
}
}