[TCP_IPV4]: Use kmemdup where appropriate

Also use a variable to avoid the longish tp->md5sig_info-> use
in tcp_v4_md5_do_add.

Code diff stats:

[acme@newtoy net-2.6.20]$ codiff /tmp/tcp_ipv4.o.before /tmp/tcp_ipv4.o.after
/pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv4/tcp_ipv4.c:
  tcp_v4_md5_do_add     |  -62
  tcp_v4_syn_recv_sock  |  -32
  tcp_v4_parse_md5_keys |  -86
 3 functions changed, 180 bytes removed
[acme@newtoy net-2.6.20]$

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 010dff4..b7d5522 100644 (file)
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -855,15 +855,18 @@ int tcp_v4_md5_do_add(struct sock *sk, __be32 addr,
        struct tcp_sock *tp = tcp_sk(sk);
        struct tcp4_md5sig_key *keys;
 
-       key = (struct tcp4_md5sig_key *) tcp_v4_md5_do_lookup(sk, addr);
+       key = (struct tcp4_md5sig_key *)tcp_v4_md5_do_lookup(sk, addr);
        if (key) {
                /* Pre-existing entry - just update that one. */
-               kfree (key->key);
+               kfree(key->key);
                key->key = newkey;
                key->keylen = newkeylen;
        } else {
+               struct tcp_md5sig_info *md5sig;
+
                if (!tp->md5sig_info) {
-                       tp->md5sig_info = kzalloc(sizeof(*tp->md5sig_info), GFP_ATOMIC);
+                       tp->md5sig_info = kzalloc(sizeof(*tp->md5sig_info),
+                                                 GFP_ATOMIC);
                        if (!tp->md5sig_info) {
                                kfree(newkey);
                                return -ENOMEM;
@@ -873,30 +876,31 @@ int tcp_v4_md5_do_add(struct sock *sk, __be32 addr,
                        kfree(newkey);
                        return -ENOMEM;
                }
-               if (tp->md5sig_info->alloced4 == tp->md5sig_info->entries4) {
-                       keys = kmalloc((sizeof(struct tcp4_md5sig_key) *
-                                      (tp->md5sig_info->entries4 + 1)), GFP_ATOMIC);
+               md5sig = tp->md5sig_info;
+
+               if (md5sig->alloced4 == md5sig->entries4) {
+                       keys = kmalloc((sizeof(*keys) *
+                                       (md5sig->entries4 + 1)), GFP_ATOMIC);
                        if (!keys) {
                                kfree(newkey);
                                tcp_free_md5sig_pool();
                                return -ENOMEM;
                        }
 
-                       if (tp->md5sig_info->entries4)
-                               memcpy(keys, tp->md5sig_info->keys4,
-                                      (sizeof (struct tcp4_md5sig_key) *
-                                       tp->md5sig_info->entries4));
+                       if (md5sig->entries4)
+                               memcpy(keys, md5sig->keys4,
+                                      sizeof(*keys) * md5sig->entries4);
 
                        /* Free old key list, and reference new one */
-                       if (tp->md5sig_info->keys4)
-                               kfree(tp->md5sig_info->keys4);
-                       tp->md5sig_info->keys4 = keys;
-                       tp->md5sig_info->alloced4++;
+                       if (md5sig->keys4)
+                               kfree(md5sig->keys4);
+                       md5sig->keys4 = keys;
+                       md5sig->alloced4++;
                }
-               tp->md5sig_info->entries4++;
-               tp->md5sig_info->keys4[tp->md5sig_info->entries4 - 1].addr = addr;
-               tp->md5sig_info->keys4[tp->md5sig_info->entries4 - 1].key = newkey;
-               tp->md5sig_info->keys4[tp->md5sig_info->entries4 - 1].keylen = newkeylen;
+               md5sig->entries4++;
+               md5sig->keys4[md5sig->entries4 - 1].addr   = addr;
+               md5sig->keys4[md5sig->entries4 - 1].key    = newkey;
+               md5sig->keys4[md5sig->entries4 - 1].keylen = newkeylen;
        }
        return 0;
 }
@@ -998,10 +1002,9 @@ static int tcp_v4_parse_md5_keys(struct sock *sk, char __user *optval,
 
        }
 
-       newkey = kmalloc(cmd.tcpm_keylen, GFP_KERNEL);
+       newkey = kmemdup(cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL);
        if (!newkey)
                return -ENOMEM;
-       memcpy(newkey, cmd.tcpm_key, cmd.tcpm_keylen);
        return tcp_v4_md5_do_add(sk, sin->sin_addr.s_addr,
                                 newkey, cmd.tcpm_keylen);
 }
@@ -1494,12 +1497,10 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
                 * memory, then we end up not copying the key
                 * across. Shucks.
                 */
-               char *newkey = kmalloc(key->keylen, GFP_ATOMIC);
-               if (newkey) {
-                       memcpy(newkey, key->key, key->keylen);
+               char *newkey = kmemdup(key->key, key->keylen, GFP_ATOMIC);
+               if (newkey != NULL)
                        tcp_v4_md5_do_add(newsk, inet_sk(sk)->daddr,
                                          newkey, key->keylen);
-               }
        }
 #endif