Shifting more than the size of the integer is undefined.

1 files changed, 5 insertions, 1 deletions

diff --git a/src/core/gnunet-service-core.c b/src/core/gnunet-service-core.c
index 4ff73395c..5e71ef897 100644
--- a/src/core/gnunet-service-core.c
+++ b/src/core/gnunet-service-core.c
@@ -3511,7 +3511,11 @@ handle_encrypted_message (struct Neighbour *n,
     }
   if (n->last_sequence_number_received < snum)
     {
-      n->last_packets_bitmap <<= (snum - n->last_sequence_number_received);
+      int shift = (snum - n->last_sequence_number_received);
+      if (shift >= 8 * sizeof(n->last_packets_bitmap))
+        n->last_packets_bitmap = 0;
+      else
+        n->last_packets_bitmap <<= shift;
       n->last_sequence_number_received = snum;
     }