slirp: Remove code that handles socreate() failure

Now that socreate() can never fail, we can remove the code
that was trying to handle that situation.

In particular this removes code in tcp_connect() that
provoked Coverity to complain (CID 1005724): in
 closesocket(accept(inso->s, (struct sockaddr *)&addr, &addrlen));
if the accept() call fails then we pass closesocket() -1
instead of a valid file descriptor.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NSamuel Thibault <samuel.thibault@ens-lyon.org>

slirp/ip_icmp.c

@@ -160,7 +160,7 @@ icmp_input(struct mbuf *m, int hlen)
     } else {
       struct socket *so;
       struct sockaddr_storage addr;
-      if ((so = socreate(slirp)) == NULL) goto freeit;
+      so = socreate(slirp);
       if (icmp_send(so, m, hlen) == 0) {
         return;
       }

slirp/slirp.c

@@ -1477,9 +1477,6 @@ static int slirp_state_load(QEMUFile *f, void *opaque, int version_id)
         int ret;
         struct socket *so = socreate(slirp);
 
-        if (!so)
-            return -ENOMEM;
-
         ret = vmstate_load_state(f, &vmstate_slirp_socket, so, version_id);
 
         if (ret < 0)

slirp/socket.c

@@ -713,9 +713,6 @@ tcp_listen(Slirp *slirp, uint32_t haddr, u_int hport, uint32_t laddr,
 	DEBUG_ARG("flags = %x", flags);
 
 	so = socreate(slirp);
-	if (!so) {
-	  return NULL;
-	}
 
 	/* Don't tcp_attach... we don't need so_snd nor so_rcv */
 	if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL) {

slirp/tcp_input.c

@@ -429,8 +429,7 @@ findso:
 	  if ((tiflags & (TH_SYN|TH_FIN|TH_RST|TH_URG|TH_ACK)) != TH_SYN)
 	    goto dropwithreset;
 
-	  if ((so = socreate(slirp)) == NULL)
-	    goto dropwithreset;
+          so = socreate(slirp);
 	  if (tcp_attach(so) < 0) {
             g_free(so); /* Not sofree (if it failed, it's not insqued) */
             goto dropwithreset;

slirp/tcp_subr.c

@@ -469,11 +469,6 @@ void tcp_connect(struct socket *inso)
         so = inso;
     } else {
         so = socreate(slirp);
-        if (so == NULL) {
-            /* If it failed, get rid of the pending connection */
-            closesocket(accept(inso->s, (struct sockaddr *)&addr, &addrlen));
-            return;
-        }
         if (tcp_attach(so) < 0) {
             g_free(so); /* NOT sofree */
             return;

slirp/udp.c

@@ -171,9 +171,6 @@ udp_input(register struct mbuf *m, int iphlen)
 	   * create one
 	   */
 	  so = socreate(slirp);
-	  if (!so) {
-	      goto bad;
-	  }
 	  if (udp_attach(so, AF_INET) == -1) {
 	    DEBUG_MISC((dfd," udp_attach errno = %d-%s\n",
 			errno,strerror(errno)));
@@ -331,9 +328,6 @@ udp_listen(Slirp *slirp, uint32_t haddr, u_int hport, uint32_t laddr,
 	socklen_t addrlen = sizeof(struct sockaddr_in);
 
 	so = socreate(slirp);
-	if (!so) {
-	    return NULL;
-	}
 	so->s = qemu_socket(AF_INET,SOCK_DGRAM,0);
         if (so->s < 0) {
             sofree(so);

slirp/udp6.c

@@ -91,9 +91,6 @@ void udp6_input(struct mbuf *m)
     if (so == NULL) {
         /* If there's no socket for this packet, create one. */
         so = socreate(slirp);
-        if (!so) {
-            goto bad;
-        }
         if (udp_attach(so, AF_INET6) == -1) {
             DEBUG_MISC((dfd, " udp6_attach errno = %d-%s\n",
                         errno, strerror(errno)));