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authorZack Weinberg <zackw@panix.com>2018-03-07 14:32:03 -0500
committerGabriel F. T. Gomes <gabriel@inconstante.eti.br>2018-12-05 18:15:43 -0200
commit4e2f43f842ef5e253cc23383645adbaa03cedb86 (patch)
treeca359423ba6ed4bb4d5ec247905a6ee13d456864 /debug/vdprintf_chk.c
parent124fc732c15ef37b7ee9db25b1e9f9b20c799623 (diff)
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Use PRINTF_FORTIFY instead of _IO_FLAGS2_FORTIFY (bug 11319)
The _chk variants of all of the printf functions become much simpler.
This is the last thing that we needed _IO_acquire_lock_clear_flags2
for, so it can go as well.  I took the opportunity to make the headers
included and the names of all local variables consistent across all the
affected files.

Since we ultimately want to get rid of __no_long_double as well, it
must be possible to get all of the nontrivial effects of the _chk
functions by calling the _internal functions with appropriate flags.
For most of the __(v)xprintf_chk functions, this is covered by
PRINTF_FORTIFY plus some up-front argument checks that can be
duplicated.  However, __(v)sprintf_chk installs a custom jump table so
that it can crash instead of overflowing the output buffer.  This
functionality is moved to __vsprintf_internal, which now has a
'maxlen' argument like __vsnprintf_internal; to get the unsafe
behavior of ordinary (v)sprintf, pass -1 for that argument.

obstack_printf_chk and obstack_vprintf_chk are no longer in the same
file.

As a side-effect of the unification of both fortified and non-fortified
vdprintf initialization, this patch fixes bug 11319 for __dprintf_chk
and __vdprintf_chk, which was previously fixed only for dprintf and
vdprintf by the commit

commit 7ca890b88e6ab7624afb1742a9fffb37ad5b3fc3
Author: Ulrich Drepper <drepper@redhat.com>
Date:   Wed Feb 24 16:07:57 2010 -0800

    Fix reporting of I/O errors in *dprintf functions.

This patch adds a test case to avoid regressions.

Tested for powerpc and powerpc64le.
Diffstat (limited to 'debug/vdprintf_chk.c')
-rw-r--r--debug/vdprintf_chk.c37
1 files changed, 5 insertions, 32 deletions
diff --git a/debug/vdprintf_chk.c b/debug/vdprintf_chk.c
index 4386127cfe..e04514e355 100644
--- a/debug/vdprintf_chk.c
+++ b/debug/vdprintf_chk.c
@@ -24,41 +24,14 @@
    This exception applies to code released by its copyright holders
    in files containing the exception.  */
 
-#include <libioP.h>
-#include <stdio_ext.h>
+#include <libio/libioP.h>
 
 int
-__vdprintf_chk (int d, int flags, const char *format, va_list arg)
+__vdprintf_chk (int d, int flag, const char *format, va_list ap)
 {
-  struct _IO_FILE_plus tmpfil;
-  struct _IO_wide_data wd;
-  int done;
-
-#ifdef _IO_MTSAFE_IO
-  tmpfil.file._lock = NULL;
-#endif
-  _IO_no_init (&tmpfil.file, _IO_USER_LOCK, 0, &wd, &_IO_wfile_jumps);
-  _IO_JUMPS (&tmpfil) = &_IO_file_jumps;
-  _IO_new_file_init_internal (&tmpfil);
-  if (_IO_file_attach (&tmpfil.file, d) == NULL)
-    {
-      _IO_un_link (&tmpfil);
-      return EOF;
-    }
-  tmpfil.file._flags |= _IO_DELETE_DONT_CLOSE;
-
-  _IO_mask_flags (&tmpfil.file, _IO_NO_READS,
-		  _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING);
-
-  /* For flags > 0 (i.e. __USE_FORTIFY_LEVEL > 1) request that %n
+  /* For flag > 0 (i.e. __USE_FORTIFY_LEVEL > 1) request that %n
      can only come from read-only format strings.  */
-  if (flags > 0)
-    tmpfil.file._flags2 |= _IO_FLAGS2_FORTIFY;
-
-  done = __vfprintf_internal (&tmpfil.file, format, arg, 0);
-
-  _IO_FINISH (&tmpfil.file);
+  unsigned int mode = (flag > 0) ? PRINTF_FORTIFY : 0;
 
-  return done;
+  return __vdprintf_internal (d, format, ap, mode);
 }
-libc_hidden_def (__vdprintf_chk)