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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/obprintf_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/obprintf_chk.c')
-rw-r--r--debug/obprintf_chk.c96
1 files changed, 10 insertions, 86 deletions
diff --git a/debug/obprintf_chk.c b/debug/obprintf_chk.c
index 41dd481c34..c1a8f9e9a9 100644
--- a/debug/obprintf_chk.c
+++ b/debug/obprintf_chk.c
@@ -17,99 +17,23 @@
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
-
-#include <stdlib.h>
-#include <libioP.h>
-#include "../libio/strfile.h"
-#include <assert.h>
-#include <string.h>
-#include <errno.h>
-#include <obstack.h>
+#include <libio/libioP.h>
#include <stdarg.h>
-#include <stdio_ext.h>
-
-
-struct _IO_obstack_file
-{
- struct _IO_FILE_plus file;
- struct obstack *obstack;
-};
-
-extern const struct _IO_jump_t _IO_obstack_jumps libio_vtable attribute_hidden;
-
-int
-__obstack_vprintf_chk (struct obstack *obstack, int flags, const char *format,
- va_list args)
-{
- struct obstack_FILE
- {
- struct _IO_obstack_file ofile;
- } new_f;
- int result;
- int size;
- int room;
-
-#ifdef _IO_MTSAFE_IO
- new_f.ofile.file.file._lock = NULL;
-#endif
-
- _IO_no_init (&new_f.ofile.file.file, _IO_USER_LOCK, -1, NULL, NULL);
- _IO_JUMPS (&new_f.ofile.file) = &_IO_obstack_jumps;
- room = obstack_room (obstack);
- size = obstack_object_size (obstack) + room;
- if (size == 0)
- {
- /* We have to handle the allocation a bit different since the
- `_IO_str_init_static' function would handle a size of zero
- different from what we expect. */
-
- /* Get more memory. */
- obstack_make_room (obstack, 64);
-
- /* Recompute how much room we have. */
- room = obstack_room (obstack);
- size = room;
-
- assert (size != 0);
- }
-
- _IO_str_init_static_internal ((struct _IO_strfile_ *) &new_f.ofile,
- obstack_base (obstack),
- size, obstack_next_free (obstack));
- /* Now allocate the rest of the current chunk. */
- assert (size == (new_f.ofile.file.file._IO_write_end
- - new_f.ofile.file.file._IO_write_base));
- assert (new_f.ofile.file.file._IO_write_ptr
- == (new_f.ofile.file.file._IO_write_base
- + obstack_object_size (obstack)));
- obstack_blank_fast (obstack, room);
-
- new_f.ofile.obstack = obstack;
-
- /* For flags > 0 (i.e. __USE_FORTIFY_LEVEL > 1) request that %n
- can only come from read-only format strings. */
- if (flags > 0)
- new_f.ofile.file.file._flags2 |= _IO_FLAGS2_FORTIFY;
-
- result = __vfprintf_internal (&new_f.ofile.file.file, format, args, 0);
-
- /* Shrink the buffer to the space we really currently need. */
- obstack_blank_fast (obstack, (new_f.ofile.file.file._IO_write_ptr
- - new_f.ofile.file.file._IO_write_end));
-
- return result;
-}
-libc_hidden_def (__obstack_vprintf_chk)
int
-__obstack_printf_chk (struct obstack *obstack, int flags, const char *format,
+__obstack_printf_chk (struct obstack *obstack, int flag, const char *format,
...)
{
- int result;
+ /* For flag > 0 (i.e. __USE_FORTIFY_LEVEL > 1) request that %n
+ can only come from read-only format strings. */
+ unsigned int mode = (flag > 0) ? PRINTF_FORTIFY : 0;
va_list ap;
+ int ret;
+
va_start (ap, format);
- result = __obstack_vprintf_chk (obstack, flags, format, ap);
+ ret = __obstack_vprintf_internal (obstack, format, ap, mode);
va_end (ap);
- return result;
+
+ return ret;
}