Fix waitpid() loop again: do the errno check only if waitpid() returns -1

and check WIFEXITED() only if it returns != -1.  Delete the logging of
errors other than ECHILD: EFAULT and EINVAL are impossible here.

ok deraadt@ millert@

diff --git a/lib/libc/gen/auth_subr.c b/lib/libc/gen/auth_subr.c
index 0df70c4..70c9160 100644 (file)
--- a/lib/libc/gen/auth_subr.c
+++ b/lib/libc/gen/auth_subr.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: auth_subr.c,v 1.46 2015/10/22 23:55:51 mmcc Exp $     */
+/*     $OpenBSD: auth_subr.c,v 1.47 2015/10/23 04:52:21 guenther Exp $ */
 
 /*
  * Copyright (c) 2000-2002,2004 Todd C. Miller <Todd.Miller@courtesan.com>
@@ -896,17 +896,17 @@ auth_call(auth_session_t *as, char *path, ...)
                as->index = 0;
                _auth_spool(as, pfd[0]);
                close(pfd[0]);
-               status = 0;
-               while (waitpid(pid, &status, 0) == -1 && errno == EINTR)
-                       ;
-               if (pid < 0) {
-                       if (errno != ECHILD) {
-                               syslog(LOG_ERR, "%s: waitpid: %m", path);
-                               warnx("internal failure");
-                               goto fail;
+               do {
+                       if (waitpid(pid, &status, 0) != -1) {
+                               if (!WIFEXITED(status))
+                                       goto fail;
+                               break;
                        }
-               } else if (!WIFEXITED(status))
-                       goto fail;
+                       /*
+                        * could get ECHILD if it was waited for by
+                        * another thread or from a signal handler
+                        */
+               } while (errno == EINTR);
        }
 
        /*