check and handle

diff --git a/src/util/server_mst.c b/src/util/server_mst.c
index 0856ba57623b50db4a7c5fccdfe48336624e5070..835d8eebaaa0a874f8857f43d7abf368c10cc6ef 100644 (file)
--- a/src/util/server_mst.c
+++ b/src/util/server_mst.c
@@ -251,6 +251,12 @@ GNUNET_SERVER_mst_receive (struct GNUNET_SERVER_MessageStreamTokenizer *mst,
          /* can try to do zero-copy and process directly from original buffer */
          hdr = (const struct GNUNET_MessageHeader *) buf;
          want = ntohs (hdr->size);
+         if (want < sizeof (struct GNUNET_MessageHeader))
+           {
+             GNUNET_break_op (0);
+             mst->off = 0;
+             return GNUNET_SYSERR;
+           }
          if (size < want)
            break; /* or not, buffer incomplete, so copy to private buffer... */
          if (one_shot == GNUNET_SYSERR)