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>

1 files changed, 1 insertions, 2 deletions

diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 46a85c9e1f25..c2025f159641 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -486,8 +486,7 @@ struct tcp_timewait_sock {
         u32                       tw_ts_recent;
         long                      tw_ts_recent_stamp;
 #ifdef CONFIG_TCP_MD5SIG
-        u16                       tw_md5_keylen;
-        u8                        tw_md5_key[TCP_MD5SIG_MAXKEYLEN];
+        struct tcp_md5sig_key   *tw_md5_key;
 #endif
         /* Few sockets in timewait have cookies; in that case, then this
          * object holds a reference to them (tw_cookie_values->kref).