bpo-33706: Fix pymain_parse_cmdline_impl() (GH-7283)
Fix a crash in Python initialization when parsing the command line
options.
Fix memcpy() size parameter: previously, we read one wchar_t after
the end of _PyOS_optarg. Moreover, don't copy the trailingg NUL
character: we write it manually anyway.
Thanks Christoph Gohlke for the bug report and the fix!
(cherry picked from commit 58d1683255abb0df4fc70960da6121aeaa41e1d1)
Co-authored-by: Victor Stinner <vstinner@redhat.com>
diff --git a/Misc/NEWS.d/next/Core and Builtins/2018-05-31-14-50-04.bpo-33706.ztlH04.rst b/Misc/NEWS.d/next/Core and Builtins/2018-05-31-14-50-04.bpo-33706.ztlH04.rst
new file mode 100644
index 0000000..d3b8477
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2018-05-31-14-50-04.bpo-33706.ztlH04.rst
@@ -0,0 +1,2 @@
+Fix a crash in Python initialization when parsing the command line options.
+Thanks Christoph Gohlke for the bug report and the fix!
diff --git a/Modules/main.c b/Modules/main.c
index 9cbb3f1..286ad41 100644
--- a/Modules/main.c
+++ b/Modules/main.c
@@ -761,7 +761,7 @@
pymain->err = _Py_INIT_NO_MEMORY();
return -1;
}
- memcpy(command, _PyOS_optarg, len * sizeof(wchar_t));
+ memcpy(command, _PyOS_optarg, (len - 2) * sizeof(wchar_t));
command[len - 2] = '\n';
command[len - 1] = 0;
pymain->command = command;