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-rw-r--r--ChangeLog5
-rw-r--r--stdio-common/printf_fp.c11
-rw-r--r--stdio-common/vfprintf.c49
3 files changed, 45 insertions, 20 deletions
diff --git a/ChangeLog b/ChangeLog
index 25c528e..6876b83 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2009-09-28 Andreas Schwab <schwab@redhat.com>
+
+ * stdio-common/printf_fp.c: Check for and avoid integer overflows.
+ * stdio-common/vfprintf.c: Likewise.
+
2009-09-28 Ulrich Drepper <drepper@redhat.com>
* locale/programs/locale-spec.c (locale_special): If nothing matches
diff --git a/stdio-common/printf_fp.c b/stdio-common/printf_fp.c
index cd3ada6..b60ddec 100644
--- a/stdio-common/printf_fp.c
+++ b/stdio-common/printf_fp.c
@@ -891,8 +891,15 @@ ___printf_fp (FILE *fp,
it is possible that we need two more characters in front of all the
other output. If the amount of memory we have to allocate is too
large use `malloc' instead of `alloca'. */
- size_t wbuffer_to_alloc = (2 + (size_t) chars_needed) * sizeof (wchar_t);
- buffer_malloced = ! __libc_use_alloca (chars_needed * 2 * sizeof (wchar_t));
+ if (__builtin_expect (chars_needed >= (size_t) -1 / sizeof (wchar_t) - 2
+ || chars_needed < fracdig_max, 0))
+ {
+ /* Some overflow occurred. */
+ __set_errno (ERANGE);
+ return -1;
+ }
+ size_t wbuffer_to_alloc = (2 + chars_needed) * sizeof (wchar_t);
+ buffer_malloced = ! __libc_use_alloca (wbuffer_to_alloc);
if (__builtin_expect (buffer_malloced, 0))
{
wbuffer = (wchar_t *) malloc (wbuffer_to_alloc);
diff --git a/stdio-common/vfprintf.c b/stdio-common/vfprintf.c
index 38ba8ff..6e0e85c 100644
--- a/stdio-common/vfprintf.c
+++ b/stdio-common/vfprintf.c
@@ -1439,23 +1439,29 @@ vfprintf (FILE *s, const CHAR_T *format, va_list ap)
left = 1;
}
- if (width + 32 >= (int) (sizeof (work_buffer)
- / sizeof (work_buffer[0])))
+ if (__builtin_expect (width >= (size_t) -1 / sizeof (CHAR_T) - 32, 0))
+ {
+ __set_errno (ERANGE);
+ done = -1;
+ goto all_done;
+ }
+
+ if (width >= sizeof (work_buffer) / sizeof (work_buffer[0]) - 32)
{
/* We have to use a special buffer. The "32" is just a safe
bet for all the output which is not counted in the width. */
- if (__libc_use_alloca ((width + 32) * sizeof (CHAR_T)))
- workend = ((CHAR_T *) alloca ((width + 32) * sizeof (CHAR_T))
- + (width + 32));
+ size_t needed = ((size_t) width + 32) * sizeof (CHAR_T);
+ if (__libc_use_alloca (needed))
+ workend = (CHAR_T *) alloca (needed) + width + 32;
else
{
- workstart = (CHAR_T *) malloc ((width + 32) * sizeof (CHAR_T));
+ workstart = (CHAR_T *) malloc (needed);
if (workstart == NULL)
{
done = -1;
goto all_done;
}
- workend = workstart + (width + 32);
+ workend = workstart + width + 32;
}
}
}
@@ -1465,22 +1471,29 @@ vfprintf (FILE *s, const CHAR_T *format, va_list ap)
LABEL (width):
width = read_int (&f);
- if (width + 32 >= (int) (sizeof (work_buffer) / sizeof (work_buffer[0])))
+ if (__builtin_expect (width >= (size_t) -1 / sizeof (CHAR_T) - 32, 0))
+ {
+ __set_errno (ERANGE);
+ done = -1;
+ goto all_done;
+ }
+
+ if (width >= sizeof (work_buffer) / sizeof (work_buffer[0]) - 32)
{
/* We have to use a special buffer. The "32" is just a safe
bet for all the output which is not counted in the width. */
- if (__libc_use_alloca ((width + 32) * sizeof (CHAR_T)))
- workend = ((CHAR_T *) alloca ((width + 32) * sizeof (CHAR_T))
- + (width + 32));
+ size_t needed = ((size_t) width + 32) * sizeof (CHAR_T);
+ if (__libc_use_alloca (needed))
+ workend = (CHAR_T *) alloca (needed) + width + 32;
else
{
- workstart = (CHAR_T *) malloc ((width + 32) * sizeof (CHAR_T));
+ workstart = (CHAR_T *) malloc (needed);
if (workstart == NULL)
{
done = -1;
goto all_done;
}
- workend = workstart + (width + 32);
+ workend = workstart + width + 32;
}
}
if (*f == L_('$'))
@@ -1510,18 +1523,18 @@ vfprintf (FILE *s, const CHAR_T *format, va_list ap)
else
prec = 0;
if (prec > width
- && prec + 32 > (int)(sizeof (work_buffer) / sizeof (work_buffer[0])))
+ && prec > sizeof (work_buffer) / sizeof (work_buffer[0]) - 32)
{
- if (__builtin_expect (prec > ~((size_t) 0) / sizeof (CHAR_T) - 31,
- 0))
+ if (__builtin_expect (prec >= (size_t) -1 / sizeof (CHAR_T) - 32, 0))
{
+ __set_errno (ERANGE);
done = -1;
goto all_done;
}
size_t needed = ((size_t) prec + 32) * sizeof (CHAR_T);
if (__libc_use_alloca (needed))
- workend = (((CHAR_T *) alloca (needed)) + ((size_t) prec + 32));
+ workend = (CHAR_T *) alloca (needed) + prec + 32;
else
{
workstart = (CHAR_T *) malloc (needed);
@@ -1530,7 +1543,7 @@ vfprintf (FILE *s, const CHAR_T *format, va_list ap)
done = -1;
goto all_done;
}
- workend = workstart + ((size_t) prec + 32);
+ workend = workstart + prec + 32;
}
}
JUMP (*f, step2_jumps);