Merged revisions 73677,73681 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

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  r73677 | hirokazu.yamamoto | 2009-06-29 22:25:16 +0900 | 2 lines

  Issue #6344: Fixed a crash of mmap.read() when passed a negative argument.
  Reviewed by Amaury Forgeot d'Arc.
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  r73681 | hirokazu.yamamoto | 2009-06-29 23:29:31 +0900 | 1 line

  Fixed NEWS.
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This commit is contained in:
Hirokazu Yamamoto 2009-06-29 14:54:12 +00:00
parent 4b1f3e55c7
commit 7a9e1bd924
2 changed files with 15 additions and 3 deletions

View File

@ -17,6 +17,8 @@ Core and Builtins
Library
-------
- Issue #6344: Fixed a crash of mmap.read() when passed a negative argument.
- The deprecated function string.maketrans has been removed.
Build

View File

@ -238,7 +238,7 @@ static PyObject *
mmap_read_method(mmap_object *self,
PyObject *args)
{
Py_ssize_t num_bytes;
Py_ssize_t num_bytes, n;
PyObject *result;
CHECK_VALID(NULL);
@ -246,8 +246,18 @@ mmap_read_method(mmap_object *self,
return(NULL);
/* silently 'adjust' out-of-range requests */
if (num_bytes > self->size - self->pos) {
num_bytes -= (self->pos+num_bytes) - self->size;
assert(self->size >= self->pos);
n = self->size - self->pos;
/* The difference can overflow, only if self->size is greater than
* PY_SSIZE_T_MAX. But then the operation cannot possibly succeed,
* because the mapped area and the returned string each need more
* than half of the addressable memory. So we clip the size, and let
* the code below raise MemoryError.
*/
if (n < 0)
n = PY_SSIZE_T_MAX;
if (num_bytes < 0 || num_bytes > n) {
num_bytes = n;
}
result = PyBytes_FromStringAndSize(self->data+self->pos, num_bytes);
self->pos += num_bytes;