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-rw-r--r--csu/check_fds.c102
1 files changed, 0 insertions, 102 deletions
diff --git a/csu/check_fds.c b/csu/check_fds.c
deleted file mode 100644
index 10ba3da395..0000000000
--- a/csu/check_fds.c
+++ /dev/null
@@ -1,102 +0,0 @@
-/* Copyright (C) 2000, 2002, 2003, 2005 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, 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 <unistd.h>
-#include <sys/stat.h>
-#include <sys/sysmacros.h>
-
-/* Try to get a machine dependent instruction which will make the
-   program crash.  This is used in case everything else fails.  */
-#include <abort-instr.h>
-#ifndef ABORT_INSTRUCTION
-/* No such instruction is available.  */
-# define ABORT_INSTRUCTION
-#endif
-
-#include <device-nrs.h>
-#include <not-cancel.h>
-
-
-/* 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)
-{
-  /* Note that fcntl() with this parameter is not a cancellation point.  */
-  if (__builtin_expect (__libc_fcntl (fd, F_GETFD), 0) == -1
-      && errno == EBADF)
-    {
-      const char *name;
-      dev_t dev;
-
-      /* For writable descriptors we use /dev/full.  */
-      if ((mode & O_ACCMODE) == O_WRONLY)
-	{
-	  name = _PATH_DEV "full";
-	  dev = makedev (DEV_FULL_MAJOR, DEV_FULL_MINOR);
-	}
-      else
-	{
-	  name = _PATH_DEVNULL;
-	  dev = makedev (DEV_NULL_MAJOR, DEV_NULL_MINOR);
-	}
-
-      /* 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 = open_not_cancel (name, mode, 0);
-
-      /* We are very paranoid here.  With all means we try to ensure
-	 that we are actually opening the /dev/null device and nothing
-	 else.
-
-	 Note that the following code assumes that STDIN_FILENO,
-	 STDOUT_FILENO, STDERR_FILENO are the three lowest file
-	 decsriptor numbers, in this order.  */
-      struct stat64 st;
-      if (__builtin_expect (nullfd != fd, 0)
-	  || __builtin_expect (__fxstat64 (_STAT_VER, fd, &st), 0) != 0
-	  || __builtin_expect (S_ISCHR (st.st_mode), 1) == 0
-	  || st.st_rdev != dev)
-	/* We cannot even give an error message here since it would
-	   run into the same problems.  */
-	while (1)
-	  /* Try for ever and ever.  */
-	  ABORT_INSTRUCTION;
-    }
-}
-
-
-void
-__libc_check_standard_fds (void)
-{
-  /* This is really paranoid but some people actually are.  If /dev/null
-     should happen to be a symlink to somewhere else and not the device
-     commonly known as "/dev/null" we bail out.  We can detect this with
-     the O_NOFOLLOW flag for open() but only on some system.  */
-#ifndef O_NOFOLLOW
-# define O_NOFOLLOW	0
-#endif
-  /* Check all three standard file descriptors.  */
-  check_one_fd (STDIN_FILENO, O_WRONLY | O_NOFOLLOW);
-  check_one_fd (STDOUT_FILENO, O_RDONLY | O_NOFOLLOW);
-  check_one_fd (STDERR_FILENO, O_RDONLY | O_NOFOLLOW);
-}