From d113fd4e0756b1b6f5543a47d0943af4564293ff Mon Sep 17 00:00:00 2001
From: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Date: May 06 2021 12:51:08 +0000
Subject: core/service: also reject deserialized commands with no argv[0]


I'm pretty sure that bad things would happen later on.

(cherry picked from commit 90204792461030dbc8645d8511e7ac8d1b4f1ca2)

---

diff --git a/src/core/service.c b/src/core/service.c
index 60eb43a..e8e51b1 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -2783,13 +2783,14 @@ static int service_deserialize_exec_command(
                                 return -ENOMEM;
                         break;
                 default:
-                        assert_not_reached("Unknown error at deserialization of exec command");
-                        break;
+                        assert_not_reached("Logic error in exec command deserialization");
                 }
         }
 
         if (state != STATE_EXEC_COMMAND_ARGS)
                 return -EINVAL;
+        if (strv_isempty(argv))
+                return -EINVAL; /* At least argv[0] must be always present. */
 
         /* Let's check whether exec command on given offset matches data that we just deserialized */
         for (command = s->exec_command[id], i = 0; command; command = command->command_next, i++) {