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| author | Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> | 2019-05-12 02:37:15 -0700 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2019-05-12 02:37:15 -0700 |
| commit | b7e483b6d07081d5f81860258e95785975a7cbf8 (patch) | |
| tree | e13640130cdfe2dea53d1f4e7256bd02b9a49842 /Python | |
| parent | 4f5febdf955240b6064bb5647dec084feaa98376 (diff) | |
| download | cpython-git-b7e483b6d07081d5f81860258e95785975a7cbf8.tar.gz | |
bpo-36791: Safer detection of integer overflow in sum(). (GH-13080)
(cherry picked from commit 29500737d45cbca9604d9ce845fb2acc3f531401)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Diffstat (limited to 'Python')
| -rw-r--r-- | Python/bltinmodule.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c index 6306c3ac56..8083ac961f 100644 --- a/Python/bltinmodule.c +++ b/Python/bltinmodule.c @@ -2374,9 +2374,11 @@ builtin_sum_impl(PyObject *module, PyObject *iterable, PyObject *start) } if (PyLong_CheckExact(item)) { long b = PyLong_AsLongAndOverflow(item, &overflow); - long x = i_result + b; - if (overflow == 0 && ((x^i_result) >= 0 || (x^b) >= 0)) { - i_result = x; + if (overflow == 0 && + (i_result >= 0 ? (b <= LONG_MAX - i_result) + : (b >= LONG_MIN - i_result))) + { + i_result += b; Py_DECREF(item); continue; } |