[PATCH] PKCS#7: fix a possible memory leak when calculating the digest

[Denis Glazkov]

In function `pkcs7_digest`, if there is an error allocating memory
for the `shash_desc` structure, the public key signature digest
remains unfreed.

Signed-off-by: Denis Glazkov <d.glazkov@xxxxxx>
---
 crypto/asymmetric_keys/pkcs7_verify.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/crypto/asymmetric_keys/pkcs7_verify.c b/crypto/asymmetric_keys/pkcs7_verify.c
index 0b4d07aa8811..e6f648dcc02a 100644
--- a/crypto/asymmetric_keys/pkcs7_verify.c
+++ b/crypto/asymmetric_keys/pkcs7_verify.c
@@ -50,7 +50,7 @@ static int pkcs7_digest(struct pkcs7_message *pkcs7,
 	ret = -ENOMEM;
 	sig->digest = kmalloc(sig->digest_size, GFP_KERNEL);
 	if (!sig->digest)
-		goto error_no_desc;
+		goto error_no_digest;
 
 	desc = kzalloc(desc_size, GFP_KERNEL);
 	if (!desc)
@@ -117,6 +117,8 @@ static int pkcs7_digest(struct pkcs7_message *pkcs7,
 error:
 	kfree(desc);
 error_no_desc:
+	kfree(sig->digest);
+error_no_digest:
 	crypto_free_shash(tfm);
 	kleave(" = %d", ret);
 	return ret;
-- 
2.25.1