--- /dev/null
+From ffcaa2172cc1a85ddb8b783de96d38ca8855e248 Mon Sep 17 00:00:00 2001
+From: Jarkko Sakkinen <jarkko@kernel.org>
+Date: Mon, 20 May 2024 02:31:53 +0300
+Subject: KEYS: trusted: Fix memory leak in tpm2_key_encode()
+
+From: Jarkko Sakkinen <jarkko@kernel.org>
+
+commit ffcaa2172cc1a85ddb8b783de96d38ca8855e248 upstream.
+
+'scratch' is never freed. Fix this by calling kfree() in the success, and
+in the error case.
+
+Cc: stable@vger.kernel.org # +v5.13
+Fixes: f2219745250f ("security: keys: trusted: use ASN.1 TPM2 key format for the blobs")
+Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ security/keys/trusted-keys/trusted_tpm2.c | 24 ++++++++++++++++++------
+ 1 file changed, 18 insertions(+), 6 deletions(-)
+
+--- a/security/keys/trusted-keys/trusted_tpm2.c
++++ b/security/keys/trusted-keys/trusted_tpm2.c
+@@ -38,6 +38,7 @@ static int tpm2_key_encode(struct truste
+ u8 *end_work = scratch + SCRATCH_SIZE;
+ u8 *priv, *pub;
+ u16 priv_len, pub_len;
++ int ret;
+
+ priv_len = get_unaligned_be16(src) + 2;
+ priv = src;
+@@ -57,8 +58,10 @@ static int tpm2_key_encode(struct truste
+ unsigned char bool[3], *w = bool;
+ /* tag 0 is emptyAuth */
+ w = asn1_encode_boolean(w, w + sizeof(bool), true);
+- if (WARN(IS_ERR(w), "BUG: Boolean failed to encode"))
+- return PTR_ERR(w);
++ if (WARN(IS_ERR(w), "BUG: Boolean failed to encode")) {
++ ret = PTR_ERR(w);
++ goto err;
++ }
+ work = asn1_encode_tag(work, end_work, 0, bool, w - bool);
+ }
+
+@@ -69,8 +72,10 @@ static int tpm2_key_encode(struct truste
+ * trigger, so if it does there's something nefarious going on
+ */
+ if (WARN(work - scratch + pub_len + priv_len + 14 > SCRATCH_SIZE,
+- "BUG: scratch buffer is too small"))
+- return -EINVAL;
++ "BUG: scratch buffer is too small")) {
++ ret = -EINVAL;
++ goto err;
++ }
+
+ work = asn1_encode_integer(work, end_work, options->keyhandle);
+ work = asn1_encode_octet_string(work, end_work, pub, pub_len);
+@@ -79,10 +84,17 @@ static int tpm2_key_encode(struct truste
+ work1 = payload->blob;
+ work1 = asn1_encode_sequence(work1, work1 + sizeof(payload->blob),
+ scratch, work - scratch);
+- if (WARN(IS_ERR(work1), "BUG: ASN.1 encoder failed"))
+- return PTR_ERR(work1);
++ if (WARN(IS_ERR(work1), "BUG: ASN.1 encoder failed")) {
++ ret = PTR_ERR(work1);
++ goto err;
++ }
+
++ kfree(scratch);
+ return work1 - payload->blob;
++
++err:
++ kfree(scratch);
++ return ret;
+ }
+
+ struct tpm2_key_context {