policy.c: Fix check_return issue in Write_rules()

Refactor Write_rules() in policy.c to eliminate check_return issue found
by SAST analysis. Create udev rules file directly using rule_name
instead of creating temporary file and renaming it.

Signed-off-by: Anna Sztukowska <anna.sztukowska@intel.com>

diff --git a/policy.c b/policy.c
index dfaafdc07cdcd73af6e810f09d258b42ff8909bb..4d4b248d511443f8b25831aedc6a8c69adf49fa5 100644 (file)
--- a/policy.c
+++ b/policy.c
@@ -969,19 +969,13 @@ int generate_entries(int fd)
  */
 int Write_rules(char *rule_name)
 {
-       int fd;
-       char udev_rule_file[PATH_MAX];
+       int fd = fileno(stdout);
 
-       if (rule_name) {
-               strncpy(udev_rule_file, rule_name, sizeof(udev_rule_file) - 6);
-               udev_rule_file[sizeof(udev_rule_file) - 6] = '\0';
-               strcat(udev_rule_file, ".temp");
-               fd = creat(udev_rule_file,
-                          S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
-               if (fd == -1)
-                       return 1;
-       } else
-               fd = 1;
+       if (rule_name)
+               fd = creat(rule_name, 0644);
+
+       if (!is_fd_valid(fd))
+               return 1;
 
        /* write static invocation */
        if (write(fd, udev_template_start, sizeof(udev_template_start) - 1) !=
@@ -993,15 +987,14 @@ int Write_rules(char *rule_name)
                goto abort;
 
        fsync(fd);
-       if (rule_name) {
+       if (rule_name)
                close(fd);
-               rename(udev_rule_file, rule_name);
-       }
+
        return 0;
 abort:
        if (rule_name) {
                close(fd);
-               unlink(udev_rule_file);
+               unlink(rule_name);
        }
        return 1;
 }