rsa: add check after calling BN_BLINDING_lock
As the potential failure of getting lock, we need to check the return
value of the BN_BLINDING_lock() in order to avoid the dirty data.
@@ -213,7 +213,9 @@ static int rsa_blinding_convert(BN_BLINDING *b, BIGNUM *f, BIGNUM *unblind,
*/
int ret;
- BN_BLINDING_lock(b);
+ if (!BN_BLINDING_lock(b))
+ return 0;
+
ret = BN_BLINDING_convert_ex(f, unblind, b, ctx);
BN_BLINDING_unlock(b);
