svcrpc: don't leak contexts on PROC_DESTROY

commit 78794d1890708cf94e3961261e52dcec2cc34722 upstream.

Context expiry times are in units of seconds since boot, not unix time.

The use of get_seconds() here therefore sets the expiry time decades in
the future.  This prevents timely freeing of contexts destroyed by
client RPC_GSS_PROC_DESTROY requests.  We'd still free them eventually
(when the module is unloaded or the container shut down), but a lot of
contexts could pile up before then.

Fixes: c5b29f885afe "sunrpc: use seconds since boot in expiry cache"
Reported-by: Andy Adamson <andros@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 45662d7..6fdffde 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -1489,7 +1489,7 @@
 	case RPC_GSS_PROC_DESTROY:
 		if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq))
 			goto auth_err;
-		rsci->h.expiry_time = get_seconds();
+		rsci->h.expiry_time = seconds_since_boot();
 		set_bit(CACHE_NEGATIVE, &rsci->h.flags);
 		if (resv->iov_len + 4 > PAGE_SIZE)
 			goto drop;