File _service:obs_scm:backport-Fix-stringop-overflow... of Package grubby

File _service:obs_scm:backport-Fix-stringop-overflow-warning.patch of Package grubby

From c693d9d1f7b0ee4d5fa5fbbeafce3a9fbacbce52 Mon Sep 17 00:00:00 2001
From: Javier Martinez Canillas <javierm@redhat.com>
Date: Mon, 10 Feb 2020 18:15:26 +0100
Subject: [PATCH] Fix stringop-overflow warning

GCC gives the following compile warning:

grubby.c: In function 'main':
grubby.c:4508:27: error: writing 1 byte into a region of size 0 [-Werror=stringop-overflow=]
 4508 |     saved_command_line[0] = '\0';
      |     ~~~~~~~~~~~~~~~~~~~~~~^~~~~~
grubby.c:4503:26: note: at offset 0 to an object with size 0 allocated by 'malloc' here
 4503 |     saved_command_line = malloc(i);
      |                          ^~~~~~~~~
cc1: all warnings being treated as errors
make: *** [Makefile:38: grubby.o] Error 1

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---
 grubby.c | 33 ++++++++++++++++++---------------
 1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/grubby.c b/grubby.c
index b8115dd..5de935d 100644
--- a/grubby.c
+++ b/grubby.c
@@ -4675,24 +4675,27 @@ int main(int argc, const char ** argv) {
     int i = 0;
     for (int j = 1; j < argc; j++)
 	i += strlen(argv[j]) + 1;
-    saved_command_line = malloc(i);
-    if (!saved_command_line) {
-	fprintf(stderr, "grubby: %m\n");
-	exit(1);
-    }
-    saved_command_line[0] = '\0';
-    int cmdline_len = 0, arg_len;
-    for (int j = 1; j < argc; j++) {
-        arg_len = strlen(argv[j]);
-        memcpy(saved_command_line + cmdline_len, argv[j], arg_len);
-        cmdline_len += arg_len;
-        if (j != argc - 1) {
-            memcpy(saved_command_line + cmdline_len, " ", 1);
-            cmdline_len++;
-        }
+    if (i > 0) {
+            saved_command_line = malloc(i);
+             if (!saved_command_line) {
+                     fprintf(stderr, "grubby: %m\n");
+                     exit(1);
+             }
+
+             saved_command_line[0] = '\0';
+             int cmdline_len = 0, arg_len;
+             for (int j = 1; j < argc; j++) {
+                     arg_len = strlen(argv[j]);
+                     memcpy(saved_command_line + cmdline_len, argv[j], arg_len);
+                     cmdline_len += arg_len;
+                     if (j != argc - 1) {
+                             memcpy(saved_command_line + cmdline_len, " ", 1);
+                             cmdline_len++;
+                     }
+             }
+             saved_command_line[cmdline_len] = '\0';
 
     }
-    saved_command_line[cmdline_len] = '\0';
 
     optCon = poptGetContext("grubby", argc, argv, options, 0);
     poptReadDefaultConfig(optCon, 1);
-- 
1.8.3.1