From: tb <tb@openbsd.org>
Date: Wed, 17 Apr 2024 13:50:01 +0000 (+0000)
Subject: Transfer ownership before setting unused bits
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=368f6dfa92efa3adb6e9e4f4d60b3703220c4045;p=openbsd

Transfer ownership before setting unused bits

This looks like a use after free, but setting the unused bits to 0
can't actually fail.

ok jsing
---

diff --git a/lib/libcrypto/ec/ec_ameth.c b/lib/libcrypto/ec/ec_ameth.c
index 9bcda79b3e2..1c2b6be87ca 100644
--- a/lib/libcrypto/ec/ec_ameth.c
+++ b/lib/libcrypto/ec/ec_ameth.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ec_ameth.c,v 1.55 2024/04/17 13:49:18 tb Exp $ */
+/* $OpenBSD: ec_ameth.c,v 1.56 2024/04/17 13:50:01 tb Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2006.
  */
@@ -951,10 +951,12 @@ ecdh_cms_encrypt(CMS_RecipientInfo *ri)
 		penclen = i2o_ECPublicKey(eckey, &p);
 		if (penclen <= 0)
 			goto err;
+
 		ASN1_STRING_set0(pubkey, penc, penclen);
+		penc = NULL;
+
 		if (!asn1_abs_set_unused_bits(pubkey, 0))
 			goto err;
-		penc = NULL;
 
 		X509_ALGOR_set0(talg, OBJ_nid2obj(NID_X9_62_id_ecPublicKey),
 		    V_ASN1_UNDEF, NULL);