From 6b70c3dc5ab2f290fcdbe474bcb7d6fdf29eae4c Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Thu, 21 Dec 2023 11:28:55 -0800 Subject: [PATCH] gh-113343: Fix error check on mmap(2) (#113342) Fix error check on mmap(2) It should check MAP_FAILED instead of NULL for error. On mmap(2) man page: RETURN VALUE On success, mmap() returns a pointer to the mapped area. On error, the value MAP_FAILED (that is, (void *) -1) is returned, and errno is set to indicate the error. --- Python/perf_trampoline.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Python/perf_trampoline.c b/Python/perf_trampoline.c index 540b650192e..750ba18d351 100644 --- a/Python/perf_trampoline.c +++ b/Python/perf_trampoline.c @@ -247,7 +247,7 @@ new_code_arena(void) mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, // fd (not used here) 0); // offset (not used here) - if (!memory) { + if (memory == MAP_FAILED) { PyErr_SetFromErrno(PyExc_OSError); PyErr_FormatUnraisable("Failed to create new mmap for perf trampoline"); perf_status = PERF_STATUS_FAILED;