From 2c37842ff97c28876e980f1829bc732c98dcde14 Mon Sep 17 00:00:00 2001 From: Karsten Blees Date: Fri, 9 Jan 2026 20:05:01 +0000 Subject: [PATCH] mingw: let `mingw_lstat()` error early upon problems with reparse points When obtaining lstat information for reparse points, we need to call `FindFirstFile()` in addition to `GetFileInformationEx()` to obtain the type of the reparse point (symlink, mount point etc.). However, currently there is no error handling whatsoever if `FindFirstFile()` fails. Call `FindFirstFile()` before modifying the `stat *buf` output parameter and error out if the call fails. Note: The `FindFirstFile()` return value includes all the data that we get from `GetFileAttributesEx()`, so we could replace `GetFileAttributesEx()` with `FindFirstFile()`. We don't do that because `GetFileAttributesEx()` is about twice as fast for single files. I.e. we only pay the extra cost of calling `FindFirstFile()` in the rare case that we encounter a reparse point. Please also note that the indentation the remaining reparse point code changed, and hence the best way to look at this diff is with `--color-moved -w`. That code was _not_ moved because a subsequent commit will move it to an altogether different function, anyway. Signed-off-by: Karsten Blees Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- compat/mingw.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/compat/mingw.c b/compat/mingw.c index ec6c2801d3..23a926c7d1 100644 --- a/compat/mingw.c +++ b/compat/mingw.c @@ -920,6 +920,7 @@ static int has_valid_directory_prefix(wchar_t *wfilename) int mingw_lstat(const char *file_name, struct stat *buf) { WIN32_FILE_ATTRIBUTE_DATA fdata; + WIN32_FIND_DATAW findbuf = { 0 }; wchar_t wfilename[MAX_PATH]; int wlen = xutftowcs_path(wfilename, file_name); if (wlen < 0) @@ -934,6 +935,13 @@ int mingw_lstat(const char *file_name, struct stat *buf) } if (GetFileAttributesExW(wfilename, GetFileExInfoStandard, &fdata)) { + /* for reparse points, use FindFirstFile to get the reparse tag */ + if (fdata.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) { + HANDLE handle = FindFirstFileW(wfilename, &findbuf); + if (handle == INVALID_HANDLE_VALUE) + goto error; + FindClose(handle); + } buf->st_ino = 0; buf->st_gid = 0; buf->st_uid = 0; @@ -946,20 +954,16 @@ int mingw_lstat(const char *file_name, struct stat *buf) filetime_to_timespec(&(fdata.ftLastWriteTime), &(buf->st_mtim)); filetime_to_timespec(&(fdata.ftCreationTime), &(buf->st_ctim)); if (fdata.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) { - WIN32_FIND_DATAW findbuf; - HANDLE handle = FindFirstFileW(wfilename, &findbuf); - if (handle != INVALID_HANDLE_VALUE) { - if ((findbuf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) && - (findbuf.dwReserved0 == IO_REPARSE_TAG_SYMLINK)) { - buf->st_mode = S_IFLNK | S_IREAD; - if (!(findbuf.dwFileAttributes & FILE_ATTRIBUTE_READONLY)) - buf->st_mode |= S_IWRITE; - } - FindClose(handle); + if ((findbuf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) && + (findbuf.dwReserved0 == IO_REPARSE_TAG_SYMLINK)) { + buf->st_mode = S_IFLNK | S_IREAD; + if (!(findbuf.dwFileAttributes & FILE_ATTRIBUTE_READONLY)) + buf->st_mode |= S_IWRITE; } } return 0; } +error: switch (GetLastError()) { case ERROR_ACCESS_DENIED: case ERROR_SHARING_VIOLATION: