commit bdf1ff052a8e23d637f2c838fa5642d78fcedc33

Author: Paul Pluzhnikov <ppluzhnikov@google.com>

Date:   Sun Feb 22 12:01:47 2015 -0800

    Fix BZ #17269 -- _IO_wstr_overflow integer overflow

diff --git a/libio/wstrops.c b/libio/wstrops.c

index 43d847d..3993579 100644

--- a/libio/wstrops.c

+++ b/libio/wstrops.c

@@ -95,8 +95,11 @@ _IO_wstr_overflow (fp, c)

 	  wchar_t *old_buf = fp->_wide_data->_IO_buf_base;

 	  size_t old_wblen = _IO_wblen (fp);

 	  _IO_size_t new_size = 2 * old_wblen + 100;

-	  if (new_size < old_wblen)

+

+	  if (__glibc_unlikely (new_size < old_wblen)

+	      || __glibc_unlikely (new_size > SIZE_MAX / sizeof (wchar_t)))

 	    return EOF;

+

 	  new_buf

 	    = (wchar_t *) (*((_IO_strfile *) fp)->_s._allocate_buffer) (new_size

 									* sizeof (wchar_t));

@@ -186,6 +189,9 @@ enlarge_userbuf (_IO_FILE *fp, _IO_off64_t offset, int reading)

     return 1;

   _IO_size_t newsize = offset + 100;

+  if (__glibc_unlikely (newsize > SIZE_MAX / sizeof (wchar_t)))

+    return 1;

+

   wchar_t *oldbuf = wd->_IO_buf_base;

   wchar_t *newbuf

     = (wchar_t *) (*((_IO_strfile *) fp)->_s._allocate_buffer) (newsize