udp.c: call buffer_init

Nothing in udp.c call buffer_init.  This might result in start padding
underflows (assertion failures) if packets come in via routes that
don't strip (much) off the front and then go out via routes that do
add lots at the front.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/udp.c b/udp.c
index 42fbb1f697dbcfc6491a5c6b56886a9ed670098c..1e637b6e5be7740ccb53f3678496298a8f31ffe2 100644 (file)
--- a/udp.c
+++ b/udp.c
@@ -102,6 +102,7 @@ static void udp_afterpoll(void *state, struct pollfd *fds, int nfds)
            fromlen=sizeof(from);
            BUF_ASSERT_FREE(st->rbuf);
            BUF_ALLOC(st->rbuf,"udp_afterpoll");
            fromlen=sizeof(from);
            BUF_ASSERT_FREE(st->rbuf);
            BUF_ALLOC(st->rbuf,"udp_afterpoll");

+           buffer_init(st->rbuf,calculate_max_start_pad());

            rv=recvfrom(st->fd, st->rbuf->start, st->rbuf->len, 0,
                        (struct sockaddr *)&from, &fromlen);
            if (rv>0) {
            rv=recvfrom(st->fd, st->rbuf->start, st->rbuf->len, 0,
                        (struct sockaddr *)&from, &fromlen);
            if (rv>0) {