tcp: md5: rcu conversion
In order to be able to support proper RST messages for TCP MD5 flows, we
need to allow access to MD5 keys without locking listener socket.
This conversion is a nice cleanup, and shrinks size of timewait sockets
by 80 bytes.
IPv6 code reuses generic code found in IPv4 instead of duplicating it.
Control path uses GFP_KERNEL allocations instead of GFP_ATOMIC.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Shawn Lu <shawn.lu@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index 550e755..3cabafb 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -359,13 +359,11 @@
*/
do {
struct tcp_md5sig_key *key;
- memset(tcptw->tw_md5_key, 0, sizeof(tcptw->tw_md5_key));
- tcptw->tw_md5_keylen = 0;
+ tcptw->tw_md5_key = NULL;
key = tp->af_specific->md5_lookup(sk, sk);
if (key != NULL) {
- memcpy(&tcptw->tw_md5_key, key->key, key->keylen);
- tcptw->tw_md5_keylen = key->keylen;
- if (tcp_alloc_md5sig_pool(sk) == NULL)
+ tcptw->tw_md5_key = kmemdup(key, sizeof(*key), GFP_ATOMIC);
+ if (tcptw->tw_md5_key && tcp_alloc_md5sig_pool(sk) == NULL)
BUG();
}
} while (0);
@@ -405,8 +403,10 @@
{
#ifdef CONFIG_TCP_MD5SIG
struct tcp_timewait_sock *twsk = tcp_twsk(sk);
- if (twsk->tw_md5_keylen)
+ if (twsk->tw_md5_key) {
tcp_free_md5sig_pool();
+ kfree_rcu(twsk->tw_md5_key, rcu);
+ }
#endif
}
EXPORT_SYMBOL_GPL(tcp_twsk_destructor);