From: Eric Biggers <ebiggers@google.com>
Date: Wed, 22 May 2019 19:42:29 +0000 (-0700)
Subject: crypto: hmac - fix memory leak in hmac_init_tfm()
X-Git-Tag: v5.1.15~67
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7348616edde5ea7f98c9b58893e953e228c25a4b;p=thirdparty%2Fkernel%2Fstable.git

crypto: hmac - fix memory leak in hmac_init_tfm()

[ Upstream commit 7829a0c1cb9c80debfb4fdb49b4d90019f2ea1ac ]

When I added the sanity check of 'descsize', I missed that the child
hash tfm needs to be freed if the sanity check fails.  Of course this
should never happen, hence the use of WARN_ON(), but it should be fixed.

Fixes: e1354400b25d ("crypto: hash - fix incorrect HASH_MAX_DESCSIZE")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/crypto/hmac.c b/crypto/hmac.c
index 4b8c8ee8f15cc..c623778b36ba3 100644
--- a/crypto/hmac.c
+++ b/crypto/hmac.c
@@ -168,8 +168,10 @@ static int hmac_init_tfm(struct crypto_tfm *tfm)
 
 	parent->descsize = sizeof(struct shash_desc) +
 			   crypto_shash_descsize(hash);
-	if (WARN_ON(parent->descsize > HASH_MAX_DESCSIZE))
+	if (WARN_ON(parent->descsize > HASH_MAX_DESCSIZE)) {
+		crypto_free_shash(hash);
 		return -EINVAL;
+	}
 
 	ctx->hash = hash;
 	return 0;