exec: Validate that a command is given

Reported-by: Ryan Whitworth <me@ryanwhitworth.com>
Signed-off-by: Steve Bennett <steveb@workware.net.au>

1 files changed, 6 insertions, 0 deletions

diff --git a/jim-exec.c b/jim-exec.c
index 9059ca2..dac8ade 100644
--- a/jim-exec.c
+++ b/jim-exec.c
@@ -966,6 +966,12 @@ badargs:
                 break;
             }
         }
+
+        if (lastArg == firstArg) {
+            Jim_SetResultString(interp, "missing command to exec", -1);
+            goto error;
+        }
+
         /* Replace | with NULL for execv() */
         arg_array[lastArg] = NULL;
         if (lastArg == arg_count) {