Fix potential heap corruption on Windows
If len is large enough, when cast to an int it will be negative and then the
test if( len > MAX_PATH - 3 ) will not behave as expected.
diff --git a/library/x509_crt.c b/library/x509_crt.c
index f6879dd..5dc6568 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -1097,7 +1097,7 @@
WCHAR szDir[MAX_PATH];
char filename[MAX_PATH];
char *p;
- int len = (int) strlen( path );
+ size_t len = strlen( path );
WIN32_FIND_DATAW file_data;
HANDLE hFind;
@@ -1131,7 +1131,7 @@
w_ret = WideCharToMultiByte( CP_ACP, 0, file_data.cFileName,
lstrlenW( file_data.cFileName ),
- p, len - 1,
+ p, (int) len - 1,
NULL, NULL );
if( w_ret == 0 )
return( MBEDTLS_ERR_X509_FILE_IO_ERROR );