sctp: use the same clock as if sock source timestamps were on

commit cb5e173ed7c03a0d4630ce68a95a186cce3cc872 upstream.

SCTP echoes a cookie o INIT ACK chunks that contains a timestamp, for
detecting stale cookies. This cookie is echoed back to the server by the
client and then that timestamp is checked.

Thing is, if the listening socket is using packet timestamping, the
cookie is encoded with ktime_get() value and checked against
ktime_get_real(), as done by __net_timestamp().

The fix is to sctp also use ktime_get_real(), so we can compare bananas
with bananas later no matter if packet timestamping was enabled or not.

Fixes: 52db882f3fc2 ("net: sctp: migrate cookie life from timeval to ktime")
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 371a152d97599eb08cec8f75d626cd2f59a936af..642c1157028551377b87192bd062cc79a8f69520 100644 (file)
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -1652,7 +1652,7 @@ static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep,
 
        /* Set an expiration time for the cookie.  */
        cookie->c.expiration = ktime_add(asoc->cookie_life,
-                                        ktime_get());
+                                        ktime_get_real());
 
        /* Copy the peer's init packet.  */
        memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr,
@@ -1780,7 +1780,7 @@ no_hmac:
        if (sock_flag(ep->base.sk, SOCK_TIMESTAMP))
                kt = skb_get_ktime(skb);
        else
-               kt = ktime_get();
+               kt = ktime_get_real();
 
        if (!asoc && ktime_before(bear_cookie->expiration, kt)) {
                /*