Ensure that the requested memory size cannot exceed the limit imposed by a

size_t variable.
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NRichard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4357)

crypto/evp/pbe_scrypt.c

@@ -207,6 +207,8 @@ int EVP_PBE_scrypt(const char *pass, size_t passlen,
 
     if (maxmem == 0)
         maxmem = SCRYPT_MAX_MEM;
+    if (maxmem > SIZE_MAX)
+        maxmem = SIZE_MAX;
 
     if (Blen + Vlen > maxmem) {
         EVPerr(EVP_F_EVP_PBE_SCRYPT, EVP_R_MEMORY_LIMIT_EXCEEDED);