lib/utmp: merge file access

Avoid checking if the file exists before opening it.

Resolves a CodeQL report of Time-of-check time-of-use filesystem race
condition.

diff --git a/lib/utmp.c b/lib/utmp.c
index dabe8b2e81e1f239ae41b6f1d03be08ce954d162..6acd196f05c1570bceb296426f1643f60ef86078 100644 (file)
--- a/lib/utmp.c
+++ b/lib/utmp.c
@@ -85,15 +85,13 @@ static void failtmp (const char *username, const struct utmp *failent)
         * feature to be used.
         */
 
-       if (access (ftmp, F_OK) != 0) {
-               return;
-       }
-
        fd = open (ftmp, O_WRONLY | O_APPEND);
        if (-1 == fd) {
-               SYSLOG ((LOG_WARN,
-                        "Can't append failure of user %s to %s.",
-                        username, ftmp));
+               if (errno != ENOENT) {
+                       SYSLOG ((LOG_WARN,
+                               "Can't append failure of user %s to %s: %m",
+                               username, ftmp));
+               }
                return;
        }