From 207e77fd3f0a94acdf0557608dd4f10ce0e0f22f Mon Sep 17 00:00:00 2001

From: Andreas Schwab <schwab@redhat.com>

Date: Mon, 9 May 2011 10:55:58 +0200

Subject: [PATCH] Never leave $ORIGIN unexpanded

* elf/dl-load.c (is_dst): Remove parameter secure, all callers

changed.  Move check for valid use of $ORIGIN ...

(_dl_dst_substitute): ... here.  Reset check_for_trusted when a

path element is skipped.

---

 ChangeLog     |    7 +++++++

 elf/dl-load.c |   34 ++++++++++++++++------------------

 2 files changed, 23 insertions(+), 18 deletions(-)

diff --git a/elf/dl-load.c b/elf/dl-load.c

index 18a83d2..6e16a9a 100644

--- a/elf/dl-load.c

+++ b/elf/dl-load.c

@@ -249,8 +249,7 @@ is_trusted_path_normalize (const char *path, size_t len)

 static size_t

-is_dst (const char *start, const char *name, const char *str,

-	int is_path, int secure)

+is_dst (const char *start, const char *name, const char *str, int is_path)

 {

   size_t len;

   bool is_curly = false;

@@ -279,12 +278,6 @@ is_dst (const char *start, const char *name, const char *str,

 	   && (!is_path || name[len] != ':'))

     return 0;

-  if (__builtin_expect (secure, 0)

-      && ((name[len] != '\0' && name[len] != '/'

-	   && (!is_path || name[len] != ':'))

-	  || (name != start + 1 && (!is_path || name[-2] != ':'))))

-    return 0;

-

   return len;

 }

@@ -299,13 +292,10 @@ _dl_dst_count (const char *name, int is_path)

     {

       size_t len;

-      /* $ORIGIN is not expanded for SUID/GUID programs (except if it

-	 is $ORIGIN alone) and it must always appear first in path.  */

       ++name;

-      if ((len = is_dst (start, name, "ORIGIN", is_path,

-			 INTUSE(__libc_enable_secure))) != 0

-	  || (len = is_dst (start, name, "PLATFORM", is_path, 0)) != 0

-	  || (len = is_dst (start, name, "LIB", is_path, 0)) != 0)

+      if ((len = is_dst (start, name, "ORIGIN", is_path)) != 0

+	  || (len = is_dst (start, name, "PLATFORM", is_path)) != 0

+	  || (len = is_dst (start, name, "LIB", is_path)) != 0)

 	++cnt;

       name = strchr (name + len, '$');

@@ -338,9 +328,16 @@ _dl_dst_substitute (struct link_map *l, const char *name, char *result,

 	  size_t len;

 	  ++name;

-	  if ((len = is_dst (start, name, "ORIGIN", is_path,

-			     INTUSE(__libc_enable_secure))) != 0)

+	  if ((len = is_dst (start, name, "ORIGIN", is_path)) != 0)

 	    {

+	      /* For SUID/GUID programs $ORIGIN must always appear

+		 first in a path element.  */

+	      if (__builtin_expect (INTUSE(__libc_enable_secure), 0)

+		  && ((name[len] != '\0' && name[len] != '/'

+		       && (!is_path || name[len] != ':'))

+		      || (name != start + 1 && (!is_path || name[-2] != ':'))))

+		repl = (const char *) -1;

+	      else

 #ifndef SHARED

 	      if (l == NULL)

 		repl = _dl_get_origin ();

@@ -351,9 +348,9 @@ _dl_dst_substitute (struct link_map *l, const char *name, char *result,

 	      check_for_trusted = (INTUSE(__libc_enable_secure)

 				   && l->l_type == lt_executable);

 	    }

-	  else if ((len = is_dst (start, name, "PLATFORM", is_path, 0)) != 0)

+	  else if ((len = is_dst (start, name, "PLATFORM", is_path)) != 0)

 	    repl = GLRO(dl_platform);

-	  else if ((len = is_dst (start, name, "LIB", is_path, 0)) != 0)

+	  else if ((len = is_dst (start, name, "LIB", is_path)) != 0)

 	    repl = DL_DST_LIB;

 	  if (repl != NULL && repl != (const char *) -1)

@@ -373,6 +370,7 @@ _dl_dst_substitute (struct link_map *l, const char *name, char *result,

 		 element, but keep an empty element at the end.  */

 	      if (wp == result && is_path && *name == ':' && name[1] != '\0')

 		++name;

+	      check_for_trusted = false;

 	    }

 	  else

 	    /* No DST we recognize.  */