Alexandre Julliard : kernel32: Attempt to buffer the full directory in FindFirstFile to avoid races.
Module: wine Branch: master Commit: 7ce90cc7198a6dee75a999e9502ff997e5d3a763 URL: http://source.winehq.org/git/wine.git/?a=commit;h=7ce90cc7198a6dee75a999e950...
Author: Alexandre Julliard julliard@winehq.org Date: Mon Feb 18 14:50:57 2013 +0100
kernel32: Attempt to buffer the full directory in FindFirstFile to avoid races.
---
dlls/kernel32/file.c | 63 +++++++++++++++++++++++++++++++++++++++++-------- 1 files changed, 52 insertions(+), 11 deletions(-)
diff --git a/dlls/kernel32/file.c b/dlls/kernel32/file.c index 91e8c8c..89e0fad 100644 --- a/dlls/kernel32/file.c +++ b/dlls/kernel32/file.c @@ -61,11 +61,14 @@ typedef struct BOOL is_root; /* is directory the root of the drive? */ UINT data_pos; /* current position in dir data */ UINT data_len; /* length of dir data */ - BYTE data[8192]; /* directory data */ + UINT data_size; /* size of data buffer, or 0 when everything has been read */ + BYTE *data; /* directory data */ } FIND_FIRST_INFO;
#define FIND_FIRST_MAGIC 0xc0ffee11
+static const UINT max_entry_size = offsetof( FILE_BOTH_DIRECTORY_INFORMATION, FileName[256] ); + static BOOL oem_file_apis;
static const WCHAR wildcardsW[] = { '*','?',0 }; @@ -1930,6 +1933,8 @@ HANDLE WINAPI FindFirstFileExW( LPCWSTR filename, FINDEX_INFO_LEVELS level, info->magic = FIND_FIRST_MAGIC; info->data_pos = 0; info->data_len = 0; + info->data_size = 0; + info->data = NULL; info->search_op = search_op;
if (device) @@ -1945,16 +1950,44 @@ HANDLE WINAPI FindFirstFileExW( LPCWSTR filename, FINDEX_INFO_LEVELS level, else { IO_STATUS_BLOCK io; + BOOL has_wildcard = strpbrkW( info->mask.Buffer, wildcardsW ) != NULL; + + info->data_size = has_wildcard ? 8192 : max_entry_size;
- NtQueryDirectoryFile( info->handle, 0, NULL, NULL, &io, info->data, sizeof(info->data), - FileBothDirectoryInformation, FALSE, &info->mask, TRUE ); - if (io.u.Status) + while (info->data_size) { - FindClose( info ); - SetLastError( RtlNtStatusToDosError( io.u.Status ) ); - return INVALID_HANDLE_VALUE; + if (!(info->data = HeapAlloc( GetProcessHeap(), 0, info->data_size ))) + { + FindClose( info ); + SetLastError( ERROR_NOT_ENOUGH_MEMORY ); + return INVALID_HANDLE_VALUE; + } + + NtQueryDirectoryFile( info->handle, 0, NULL, NULL, &io, info->data, info->data_size, + FileBothDirectoryInformation, FALSE, &info->mask, TRUE ); + if (io.u.Status) + { + FindClose( info ); + SetLastError( RtlNtStatusToDosError( io.u.Status ) ); + return INVALID_HANDLE_VALUE; + } + + if (io.Information < info->data_size - max_entry_size) + { + info->data_size = 0; /* we read everything */ + } + else if (info->data_size < 1024 * 1024) + { + HeapFree( GetProcessHeap(), 0, info->data ); + info->data_size *= 2; + } + else break; } + info->data_len = io.Information; + if (!info->data_size && has_wildcard) /* release unused buffer space */ + HeapReAlloc( GetProcessHeap(), HEAP_REALLOC_IN_PLACE_ONLY, info->data, info->data_len ); + if (!FindNextFileW( info, data )) { TRACE( "%s not found\n", debugstr_w(filename) ); @@ -1962,11 +1995,12 @@ HANDLE WINAPI FindFirstFileExW( LPCWSTR filename, FINDEX_INFO_LEVELS level, SetLastError( ERROR_FILE_NOT_FOUND ); return INVALID_HANDLE_VALUE; } - if (!strpbrkW( info->mask.Buffer, wildcardsW )) + if (!has_wildcard) /* we can't find two files with the same name */ { - /* we can't find two files with the same name */ CloseHandle( info->handle ); + HeapFree( GetProcessHeap(), 0, info->data ); info->handle = 0; + info->data = NULL; } } return info; @@ -2010,15 +2044,21 @@ BOOL WINAPI FindNextFileW( HANDLE handle, WIN32_FIND_DATAW *data ) { IO_STATUS_BLOCK io;
- NtQueryDirectoryFile( info->handle, 0, NULL, NULL, &io, info->data, sizeof(info->data), - FileBothDirectoryInformation, FALSE, &info->mask, FALSE ); + if (info->data_size) + NtQueryDirectoryFile( info->handle, 0, NULL, NULL, &io, info->data, info->data_size, + FileBothDirectoryInformation, FALSE, &info->mask, FALSE ); + else + io.u.Status = STATUS_NO_MORE_FILES; + if (io.u.Status) { SetLastError( RtlNtStatusToDosError( io.u.Status ) ); if (io.u.Status == STATUS_NO_MORE_FILES) { CloseHandle( info->handle ); + HeapFree( GetProcessHeap(), 0, info->data ); info->handle = 0; + info->data = NULL; } break; } @@ -2101,6 +2141,7 @@ BOOL WINAPI FindClose( HANDLE handle ) RtlFreeUnicodeString( &info->path ); info->data_pos = 0; info->data_len = 0; + HeapFree( GetProcessHeap(), 0, info->data ); RtlLeaveCriticalSection( &info->cs ); info->cs.DebugInfo->Spare[0] = 0; RtlDeleteCriticalSection( &info->cs );
-
Alexandre Julliard