Try to fix #51

Author: probonopd

src/runtime/runtime.c

@@ -16,7 +16,7 @@
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
+ * copies of the Software, and to permit persons to whom the Softwaref is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
@@ -865,22 +865,49 @@ bool rm_recursive(const char* const path) {
 void build_mount_point(char* mount_dir, const char* const argv0, char const* const temp_base, const size_t templen) {
     const size_t maxnamelen = 6;
 
+    // Check for NULL argv0
+    if (argv0 == NULL) {
+        fprintf(stderr, "Error: argv0 is NULL\n");
+        return;
+    }
+
     // need to copy argv0 as it's a const value, basename intends to modify it
     char* argv0_copy = strdup(argv0);
+    if (argv0_copy == NULL) {
+        fprintf(stderr, "Error: strdup failed\n");
+        return;
+    }
+
     char* path_basename = basename(argv0_copy);
-    free(argv0_copy);
+    if (path_basename == NULL) {
+        free(argv0_copy);
+        fprintf(stderr, "Error: basename returned NULL\n");
+        return;
+    }
 
     size_t namelen = strlen(path_basename);
     // limit length of tempdir name
     if (namelen > maxnamelen) {
         namelen = maxnamelen;
     }
 
+    // Ensure mount_dir has enough space
+    size_t required_length = templen + 8 + namelen + 6 + 1; // +1 for null terminator
+    if (strlen(temp_base) + required_length > sizeof(mount_dir)) {
+        free(argv0_copy);
+        fprintf(stderr, "Error: mount_dir does not have enough space\n");
+        return;
+    }
+
     strcpy(mount_dir, temp_base);
     strncpy(mount_dir + templen, "/.mount_", 8);
     strncpy(mount_dir + templen + 8, path_basename, namelen);
     strncpy(mount_dir + templen + 8 + namelen, "XXXXXX", 6);
-    mount_dir[templen + 8 + namelen + 6] = 0; // null terminate destination
+    
+    // Null terminate the destination
+    mount_dir[templen + 8 + namelen + 6] = '\0'; // null terminate destination
+
+    free(argv0_copy);
 }
 
 int fusefs_main(int argc, char* argv[], void (* mounted)(void)) {