Update.

	* csu/Makefile (routines): Add check_fds.
	* elf/rtld.c (dl_main): Call __libc_check_standard_fds for SUID
	binaries.  Add various __builtin_expect.
	* sysdeps/generic/libc-start.c: Move check_fds and helper functions...
	* sysdeps/generic/check_fds.c: ...here.  New file.

	* malloc/malloc.c (ptmalloc_init): Only enable debugging for SUID
	binaries if file /etc/suid-debug is available.

1 files changed, 7 insertions, 36 deletions

diff --git a/sysdeps/generic/libc-start.c b/sysdeps/generic/libc-start.c
index fe4966cd46..f5486f91e1 100644
--- a/sysdeps/generic/libc-start.c
+++ b/sysdeps/generic/libc-start.c
@@ -16,12 +16,8 @@
    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
    Boston, MA 02111-1307, USA.  */
 
-#include <errno.h>
-#include <fcntl.h>
-#include <paths.h>
 #include <stdlib.h>
 #include <unistd.h>
-#include <sys/ioctl.h>
 #include <ldsodefs.h>
 
 extern void __libc_init_first (int argc, char **argv, char **envp);
@@ -32,7 +28,7 @@ extern int __libc_multiple_libcs;
 extern void *__libc_stack_end;
 
 /* Prototype for local function.  */
-static void check_standard_fds (void);
+extern void __libc_check_standard_fds (void);
 
 int
 __libc_start_main (int (*main) (int, char **, char **), int argc,
@@ -54,10 +50,14 @@ __libc_start_main (int (*main) (int, char **, char **), int argc,
   /* Set the global _environ variable correctly.  */
   __environ = &argv[argc + 1];
 
+#ifndef SHARED
   /* Some security at this point.  Prevent starting a SUID binary where
-     the standard file descriptors are not opened.  */
+     the standard file descriptors are not opened.  We have to do this
+     only for statically linked applications since otherwise the dynamic
+     loader did the work already.  */
   if (__builtin_expect (__libc_enable_secure, 0))
-    check_standard_fds ();
+    __libc_check_standard_fds ();
+#endif
 
   /* Register the destructor of the dynamic linker if there is any.  */
   if (__builtin_expect (rtld_fini != NULL, 1))
@@ -89,32 +89,3 @@ __libc_start_main (int (*main) (int, char **, char **), int argc,
 
   exit ((*main) (argc, argv, __environ));
 }
-
-
-/* Should other OSes (e.g., Hurd) have different versions which can
-   be written in a better way?  */
-static void
-check_one_fd (int fd, int mode)
-{
-  if (__libc_fcntl (fd, F_GETFD) == -1 && errno == EBADF)
-    {
-      /* Something is wrong with this descriptor, it's probably not
-	 opened.  Open /dev/null so that the SUID program we are
-	 about to start does not accidently use this descriptor.  */
-      int nullfd = __libc_open (_PATH_DEVNULL, mode);
-      if (nullfd == -1)
-	/* We cannot even give an error message here since it would
-	   run into the same problems.  */
-	abort ();
-    }
-}
-
-
-static void
-check_standard_fds (void)
-{
-/* Check all three standard file descriptors.  */
-  check_one_fd (STDIN_FILENO, O_RDONLY);
-  check_one_fd (STDOUT_FILENO, O_RDWR);
-  check_one_fd (STDERR_FILENO, O_RDWR);
-}