[linux-pam] pam_exec: Do not depend on open() returning STDOUT_FILENO.

[Tomáš Mráz]

commit b03f33830c94ea39ce04a865e62a9d346dcf1a2e
Author: Tomas Mraz <tmraz(a)fedoraproject.org&gt;
Date:   Tue Aug 26 14:04:02 2014 +0200

    pam_exec: Do not depend on open() returning STDOUT_FILENO.
    
    modules/pam_exec/pam_exec.c (call_exec): Move the descriptor to
    STDOUT_FILENO if needed.

 modules/pam_exec/pam_exec.c |   12 +++++++++++-
 1 files changed, 11 insertions(+), 1 deletions(-)
---
diff --git a/modules/pam_exec/pam_exec.c b/modules/pam_exec/pam_exec.c
index 12c4444..5ab9630 100644
--- a/modules/pam_exec/pam_exec.c
+++ b/modules/pam_exec/pam_exec.c
@@ -360,9 +360,19 @@ call_exec (const char *pam_type, pam_handle_t *pamh,
 			  logfile);
 	      _exit (err);
 	    }
+	  if (i != STDOUT_FILENO)
+	    {
+	      if (dup2 (i, STDOUT_FILENO) == -1)
+		{
+		  int err = errno;
+		  pam_syslog (pamh, LOG_ERR, "dup2 failed: %m");
+		  _exit (err);
+		}
+	      close (i);
+	    }
 	  if (asprintf (&buffer, "*** %s", ctime (&tm)) > 0)
 	    {
-	      pam_modutil_write (i, buffer, strlen (buffer));
+	      pam_modutil_write (STDOUT_FILENO, buffer, strlen (buffer));
 	      free (buffer);
 	    }
 	}