From c772420fc141499cb583db6286fd09e9c9c35586 Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Fri, 23 Aug 2019 11:04:16 +0100 Subject: [PATCH] bpo-37926: Fix PySys_SetArgvEx(0, NULL, 0) crash (GH-15415) empty_argv is no longer static in Python 3.8, but it is declared in a temporary scope, whereas argv keeps a reference to it. empty_argv memory (allocated on the stack) is reused by make_sys_argv() code which is inlined when using gcc -O3. Define empty_argv in PySys_SetArgvEx() body, to ensure that it remains valid for the whole lifetime of the PySys_SetArgvEx() call. --- Misc/NEWS.d/next/C API/2019-08-23-11-35-55.bpo-37926.hnI5IQ.rst | 1 + Python/sysmodule.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) create mode 100644 Misc/NEWS.d/next/C API/2019-08-23-11-35-55.bpo-37926.hnI5IQ.rst diff --git a/Misc/NEWS.d/next/C API/2019-08-23-11-35-55.bpo-37926.hnI5IQ.rst b/Misc/NEWS.d/next/C API/2019-08-23-11-35-55.bpo-37926.hnI5IQ.rst new file mode 100644 index 00000000000000..20185330a8f4fb --- /dev/null +++ b/Misc/NEWS.d/next/C API/2019-08-23-11-35-55.bpo-37926.hnI5IQ.rst @@ -0,0 +1 @@ +Fix a crash in ``PySys_SetArgvEx(0, NULL, 0)``. diff --git a/Python/sysmodule.c b/Python/sysmodule.c index a89ebceb66c5df..738bbc826f5e16 100644 --- a/Python/sysmodule.c +++ b/Python/sysmodule.c @@ -3058,11 +3058,11 @@ make_sys_argv(int argc, wchar_t * const * argv) void PySys_SetArgvEx(int argc, wchar_t **argv, int updatepath) { + wchar_t* empty_argv[1] = {L""}; PyThreadState *tstate = _PyThreadState_GET(); if (argc < 1 || argv == NULL) { /* Ensure at least one (empty) argument is seen */ - wchar_t* empty_argv[1] = {L""}; argv = empty_argv; argc = 1; }