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Takashi Yano 3d94e07c49 newlib: libc: Fix crash on fprintf to a wide-oriented stream.
Previously, fprintf() on a wide-oriented stream crashes or outputs
garbage. This is because a narrow char string which can be odd bytes
in length is cast into a wide char string which should be even
bytes in length in __sprint_r/__sfputs_r based on the __SWID flag.
As a result, if the length is odd bytes, the reading buffer runs over
the buffer length, which causes a crash. If the length is even bytes,
garbage is printed.

With this patch, any output to the stream which is set to different
orientation fails with error just like glibc. Note that it behaves
differently from other libc implementations such as BSD, musl and
Solaris.

Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
2023-11-10 00:36:41 +09:00

136 lines
3.1 KiB
C

/*
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* and/or other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
/*
FUNCTION
<<puts>>---write a character string
INDEX
puts
INDEX
_puts_r
SYNOPSIS
#include <stdio.h>
int puts(const char *<[s]>);
int _puts_r(struct _reent *<[reent]>, const char *<[s]>);
DESCRIPTION
<<puts>> writes the string at <[s]> (followed by a newline, instead of
the trailing null) to the standard output stream.
The alternate function <<_puts_r>> is a reentrant version. The extra
argument <[reent]> is a pointer to a reentrancy structure.
RETURNS
If successful, the result is a nonnegative integer; otherwise, the
result is <<EOF>>.
PORTABILITY
ANSI C requires <<puts>>, but does not specify that the result on
success must be <<0>>; any non-negative value is permitted.
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "%W% (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */
#include <_ansi.h>
#include <reent.h>
#include <stdio.h>
#include <string.h>
#include "fvwrite.h"
#include "local.h"
/*
* Write the given string to stdout, appending a newline.
*/
int
_puts_r (struct _reent *ptr,
const char * s)
{
#ifdef _FVWRITE_IN_STREAMIO
int result;
size_t c = strlen (s);
struct __suio uio;
struct __siov iov[2];
FILE *fp;
iov[0].iov_base = s;
iov[0].iov_len = c;
iov[1].iov_base = "\n";
iov[1].iov_len = 1;
uio.uio_resid = c + 1;
uio.uio_iov = &iov[0];
uio.uio_iovcnt = 2;
_REENT_SMALL_CHECK_INIT (ptr);
fp = _stdout_r (ptr);
CHECK_INIT (ptr, fp);
_newlib_flockfile_start (fp);
if (ORIENT (fp, -1) != -1)
result = EOF;
else
result = (__sfvwrite_r (ptr, fp, &uio) ? EOF : '\n');
_newlib_flockfile_end (fp);
return result;
#else
int result = EOF;
const char *p = s;
FILE *fp;
_REENT_SMALL_CHECK_INIT (ptr);
fp = _stdout_r (ptr);
CHECK_INIT (ptr, fp);
_newlib_flockfile_start (fp);
if (ORIENT (fp, -1) != -1)
goto err;
/* Make sure we can write. */
if (cantwrite (ptr, fp))
goto err;
while (*p)
{
if (__sputc_r (ptr, *p++, fp) == EOF)
goto err;
}
if (__sputc_r (ptr, '\n', fp) == EOF)
goto err;
result = '\n';
err:
_newlib_flockfile_end (fp);
return result;
#endif
}
#ifndef _REENT_ONLY
int
puts (char const * s)
{
return _puts_r (_REENT, s);
}
#endif