From d2f900a51de27f2d9229b0ae785c02ac272bd525 Mon Sep 17 00:00:00 2001
From: Mateusz Kwiatkowski <m.kwiatkowski@avsystem.com>
Date: Thu, 10 Sep 2020 15:47:41 +0200
Subject: [PATCH] Fix potential leak in RSA method

Upstream-Status: Backport [https://github.com/OpenSC/libp11/commit/5caa2779762c3d760f33b70cd9e1f70f15f3ea57]
---
 src/p11_rsa.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/p11_rsa.c b/src/p11_rsa.c
index 221513c7..b6beef0b 100644
--- a/src/p11_rsa.c
+++ b/src/p11_rsa.c
@@ -352,6 +352,11 @@ int (*RSA_meth_get_priv_dec(const RSA_METHOD *meth))
     return meth->rsa_priv_dec;
 }
 
+static int (*RSA_meth_get_finish(const RSA_METHOD *meth)) (RSA *rsa)
+{
+    return meth->finish;
+}
+
 #endif
 
 static int pkcs11_rsa_priv_dec_method(int flen, const unsigned char *from,
@@ -383,6 +388,11 @@ static int pkcs11_rsa_priv_enc_method(int flen, const unsigned char *from,
 static int pkcs11_rsa_free_method(RSA *rsa)
 {
 	RSA_set_ex_data(rsa, rsa_ex_index, NULL);
+	int (*orig_rsa_free_method)(RSA *rsa) =
+		RSA_meth_get_finish(RSA_get_default_method());
+	if (orig_rsa_free_method) {
+		return orig_rsa_free_method(rsa);
+	}
 	return 1;
 }