From f33cf52faf733f5a6441a533f83e9b1cf2018245 Mon Sep 17 00:00:00 2001 From: "Christoph M. Becker" Date: Tue, 5 May 2020 09:31:17 +0200 Subject: Fix #79566: Private SHM is not private on Windows We map the POSIX semantics of `IPC_PRIVATE` by creating unnamed file mapping objects on Windows. While that is not particularly useful for ext/shmop, which is the only bundled extension which uses `shmget()`, it may be useful for external extensions. --- TSRM/tsrm_win32.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'TSRM') diff --git a/TSRM/tsrm_win32.c b/TSRM/tsrm_win32.c index cb2520e294..6cedaa8360 100644 --- a/TSRM/tsrm_win32.c +++ b/TSRM/tsrm_win32.c @@ -616,14 +616,16 @@ TSRM_API int shmget(key_t key, size_t size, int flags) {/*{{{*/ shm_pair *shm; char shm_segment[26], shm_info[29]; - HANDLE shm_handle, info_handle; + HANDLE shm_handle = NULL, info_handle = NULL; BOOL created = FALSE; - snprintf(shm_segment, sizeof(shm_segment), "TSRM_SHM_SEGMENT:%d", key); - snprintf(shm_info, sizeof(shm_info), "TSRM_SHM_DESCRIPTOR:%d", key); + if (key != IPC_PRIVATE) { + snprintf(shm_segment, sizeof(shm_segment), "TSRM_SHM_SEGMENT:%d", key); + snprintf(shm_info, sizeof(shm_info), "TSRM_SHM_DESCRIPTOR:%d", key); - shm_handle = OpenFileMapping(FILE_MAP_ALL_ACCESS, FALSE, shm_segment); - info_handle = OpenFileMapping(FILE_MAP_ALL_ACCESS, FALSE, shm_info); + shm_handle = OpenFileMapping(FILE_MAP_ALL_ACCESS, FALSE, shm_segment); + info_handle = OpenFileMapping(FILE_MAP_ALL_ACCESS, FALSE, shm_info); + } if (!shm_handle && !info_handle) { if (flags & IPC_CREAT) { @@ -634,8 +636,8 @@ TSRM_API int shmget(key_t key, size_t size, int flags) DWORD high = 0; DWORD low = size; #endif - shm_handle = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, high, low, shm_segment); - info_handle = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, sizeof(shm->descriptor), shm_info); + shm_handle = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, high, low, key == IPC_PRIVATE ? NULL : shm_segment); + info_handle = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, sizeof(shm->descriptor), key == IPC_PRIVATE ? NULL : shm_info); created = TRUE; } if (!shm_handle || !info_handle) { -- cgit v1.2.1