[BZ #6698]

* stdio-common/_i18n_number.h (_i18n_number_rewrite): Take additional
	parameter for end of buffer.  If temporary copy is too large use
	malloc.
	* stdio-common/vfprintf.c: Adjust for _i18n_number_rewrite
	interface change.
	* stdio-common/printf_fp.c (__printf_fp): Likewise..  Account for
	string rewrite when allocating buffer.

ChangeLog

@@ -1,5 +1,14 @@
 2008-07-25  Ulrich Drepper  <drepper@redhat.com>
 
+	[BZ #6698]
+	* stdio-common/_i18n_number.h (_i18n_number_rewrite): Take additional
+	parameter for end of buffer.  If temporary copy is too large use
+	malloc.
+	* stdio-common/vfprintf.c: Adjust for _i18n_number_rewrite
+	interface change.
+	* stdio-common/printf_fp.c (__printf_fp): Likewise..  Account for
+	string rewrite when allocating buffer.
+
 	* sysdeps/unix/sysv/linux/kernel-features.h: PPC has the new
 	syscalls, too.
 

stdio-common/_i18n_number.h

@@ -1,4 +1,4 @@
-/* Copyright (C) 2000, 2004 Free Software Foundation, Inc.
+/* Copyright (C) 2000, 2004, 2008 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@gnu.org>, 2000.
 
@@ -24,7 +24,7 @@
 #include "../locale/outdigitswc.h"
 
 static CHAR_T *
-_i18n_number_rewrite (CHAR_T *w, CHAR_T *rear_ptr)
+_i18n_number_rewrite (CHAR_T *w, CHAR_T *rear_ptr, CHAR_T *end)
 {
 #ifdef COMPILE_WPRINTF
 # define decimal NULL
@@ -58,10 +58,23 @@ _i18n_number_rewrite (CHAR_T *w, CHAR_T *rear_ptr)
 #endif
 
   /* Copy existing string so that nothing gets overwritten.  */
-  CHAR_T *src = (CHAR_T *) alloca ((rear_ptr - w) * sizeof (CHAR_T));
+  CHAR_T *src;
+  bool use_alloca = __libc_use_alloca ((rear_ptr - w) * sizeof (CHAR_T));
+  if (__builtin_expect (use_alloca, true))
+    src = (CHAR_T *) alloca ((rear_ptr - w) * sizeof (CHAR_T));
+  else
+    {
+      src = (CHAR_T *) malloc ((rear_ptr - w) * sizeof (CHAR_T));
+      if (src == NULL)
+	/* If we cannot allocate the memory don't rewrite the string.
+	   It is better than nothing.  */
+	return w;
+    }
+
   CHAR_T *s = (CHAR_T *) __mempcpy (src, w,
 				    (rear_ptr - w) * sizeof (CHAR_T));
-  w = rear_ptr;
+
+  w = end;
 
   /* Process all characters in the string.  */
   while (--s >= src)
@@ -91,5 +104,8 @@ _i18n_number_rewrite (CHAR_T *w, CHAR_T *rear_ptr)
 	}
     }
 
+  if (! use_alloca)
+    free (src);
+
   return w;
 }

stdio-common/printf_fp.c

@@ -1,5 +1,5 @@
 /* Floating point output for `printf'.
-   Copyright (C) 1995-2003, 2006, 2007 Free Software Foundation, Inc.
+   Copyright (C) 1995-2003, 2006, 2007, 2008 Free Software Foundation, Inc.
 
    This file is part of the GNU C Library.
    Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.
@@ -1148,6 +1148,7 @@ ___printf_fp (FILE *fp,
 
     {
       char *buffer = NULL;
+      char *buffer_end = NULL;
       char *cp = NULL;
       char *tmpptr;
 
@@ -1157,6 +1158,9 @@ ___printf_fp (FILE *fp,
 	  size_t decimal_len;
 	  size_t thousands_sep_len;
 	  wchar_t *copywc;
+	  size_t factor = (info->i18n
+			   ? _NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_MB_CUR_MAX)
+			   : 1);
 
 	  decimal_len = strlen (decimal);
 
@@ -1165,10 +1169,11 @@ ___printf_fp (FILE *fp,
 	  else
 	    thousands_sep_len = strlen (thousands_sep);
 
+	  size_t nbuffer = (2 + chars_needed * factor + decimal_len
+			    + ngroups * thousands_sep_len);
 	  if (__builtin_expect (buffer_malloced, 0))
 	    {
-	      buffer = (char *) malloc (2 + chars_needed + decimal_len
-					+ ngroups * thousands_sep_len);
+	      buffer = (char *) malloc (nbuffer);
 	      if (buffer == NULL)
 		{
 		  /* Signal an error to the caller.  */
@@ -1177,8 +1182,8 @@ ___printf_fp (FILE *fp,
 		}
 	    }
 	  else
-	    buffer = (char *) alloca (2 + chars_needed + decimal_len
-				      + ngroups * thousands_sep_len);
+	    buffer = (char *) alloca (nbuffer);
+	  buffer_end = buffer + nbuffer;
 
 	  /* Now copy the wide character string.  Since the character
 	     (except for the decimal point and thousands separator) must
@@ -1197,9 +1202,13 @@ ___printf_fp (FILE *fp,
       if (__builtin_expect (info->i18n, 0))
         {
 #ifdef COMPILE_WPRINTF
-	  wstartp = _i18n_number_rewrite (wstartp, wcp);
+	  wstartp = _i18n_number_rewrite (wstartp, wcp,
+					  wbuffer + wbuffer_to_alloc);
 #else
-	  tmpptr = _i18n_number_rewrite (tmpptr, cp);
+	  tmpptr = _i18n_number_rewrite (tmpptr, cp, buffer_end);
+	  cp = buffer_end;
+	  assert ((uintptr_t) buffer <= (uintptr_t) tmpptr);
+	  assert ((uintptr_t) tmpptr < (uintptr_t) buffer_end);
 #endif
         }
 

stdio-common/vfprintf.c

@@ -625,7 +625,7 @@ vfprintf (FILE *s, const CHAR_T *format, va_list ap)
 				       thousands_sep);			      \
 									      \
 	      if (use_outdigits && base == 10)				      \
-		string = _i18n_number_rewrite (string, workend);	      \
+		string = _i18n_number_rewrite (string, workend, workend);     \
 	    }								      \
 	  /* Simplify further test for num != 0.  */			      \
 	  number.word = number.longlong != 0;				      \
@@ -683,7 +683,7 @@ vfprintf (FILE *s, const CHAR_T *format, va_list ap)
 				       thousands_sep);			      \
 									      \
 	      if (use_outdigits && base == 10)				      \
-		string = _i18n_number_rewrite (string, workend);	      \
+		string = _i18n_number_rewrite (string, workend, workend);     \
 	    }								      \
 	}								      \
 									      \