sd-radv: when receiving a too short packet, make sure we dequeue it

diff --git a/src/libsystemd-network/sd-radv.c b/src/libsystemd-network/sd-radv.c
index f256cbc..7b51f28 100644 (file)
--- a/src/libsystemd-network/sd-radv.c
+++ b/src/libsystemd-network/sd-radv.c
@@ -229,9 +229,8 @@ static int radv_recv(sd_event_source *s, int fd, uint32_t revents, void *userdat
         assert(ra->event);
 
         buflen = next_datagram_size_fd(fd);
-
-        if ((unsigned) buflen < sizeof(struct nd_router_solicit))
-                return log_radv("Too short packet received");
+        if (buflen < 0)
+                return (int) buflen;
 
         buf = new0(char, buflen);
         if (!buf)
@@ -264,6 +263,11 @@ static int radv_recv(sd_event_source *s, int fd, uint32_t revents, void *userdat
                 return 0;
         }
 
+        if ((size_t) buflen < sizeof(struct nd_router_solicit)) {
+                log_radv("Too short packet received");
+                return 0;
+        }
+
         (void) in_addr_to_string(AF_INET6, (union in_addr_union*) &src, &addr);
 
         r = radv_send(ra, &src, ra->lifetime);