argv.c (expandargv): Limit the number of times that response files are opened in…

argv.c (expandargv): Limit the number of times that response files are opened in order to prevent...

        * argv.c (expandargv): Limit the number of times that response
        files are opened in order to prevent infinite recursion.

From-SVN: r163222

libiberty/ChangeLog

+2010-08-13  Nick Clifton  <nickc@redhat.com>
+
+	* argv.c (expandargv): Limit the number of times that response
+	files are opened in order to prevent infinite recursion.
+
 2010-07-21  Pascal Obry  <obry@adacore.com>
 
 	* make-temp-file.c (choose_tmpdir): Append a dot to P_tmpdir if needed.

libiberty/argv.c

 /* Create and destroy argument vectors (argv's)
-   Copyright (C) 1992, 2001 Free Software Foundation, Inc.
+   Copyright (C) 1992, 2001, 2010 Free Software Foundation, Inc.
    Written by Fred Fish @ Cygnus Support
 
 This file is part of the libiberty library.
@@ -386,6 +386,9 @@ expandargv (int *argcp, char ***argvp)
   int i = 0;
   /* Non-zero if ***argvp has been dynamically allocated.  */
   int argv_dynamic = 0;
+  /* Limit the number of response files that we parse in order
+     to prevent infinite recursion.  */
+  unsigned int iteration_limit = 2000;
   /* Loop over the arguments, handling response files.  We always skip
      ARGVP[0], as that is the name of the program being run.  */
   while (++i < *argcp)
@@ -412,6 +415,12 @@ expandargv (int *argcp, char ***argvp)
       filename = (*argvp)[i];
       if (filename[0] != '@')
 	continue;
+      /* If we have iterated too many times then stop.  */
+      if (-- iteration_limit == 0)
+	{
+	  fprintf (stderr, "%s: error: too many @-files encountered\n", (*argvp)[0]);
+	  xexit (1);
+	}
       /* Read the contents of the file.  */
       f = fopen (++filename, "r");
       if (!f)