[PATCH] realpath fix

[Jakub Jelinek]

Hi!

While looking at util-linux realpath, I found that even glibc realpath can
do weird things. __getcwd if it fails does not have to NULL terminate rpath
(and in case of ENAMETOOLONG the path is not NULL terminated either), but
then at error: we strcpy(resource, rpath); which might be very long string.

2000-02-03  Jakub Jelinek  <jakub@redhat.com>

	* stdlib/canonicalize.c (canonicalize): Zero terminate
	path to copy on error.

--- canonicalize.c.jj	Tue Feb  9 10:35:10 1999
+++ canonicalize.c	Thu Feb  3 16:24:16 2000
@@ -76,7 +76,10 @@ canonicalize (const char *name, char *re
   if (name[0] != '/')
     {
       if (!__getcwd (rpath, path_max))
-	goto error;
+	{
+	  rpath[0] = '\0';
+	  goto error;
+	}
       dest = strchr (rpath, '\0');
     }
   else
@@ -122,6 +125,9 @@ canonicalize (const char *name, char *re
 	      if (resolved)
 		{
 		  __set_errno (ENAMETOOLONG);
+		  if (dest > rpath + 1)
+		    dest--;
+		  *dest = '\0';
 		  goto error;
 		}
 	      new_size = rpath_limit - rpath;

Cheers,
    Jakub
___________________________________________________________________
Jakub Jelinek | jakub@redhat.com | http://sunsite.mff.cuni.cz/~jj
Linux version 2.3.41 on a sparc64 machine (1343.49 BogoMips)
___________________________________________________________________