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 4b8c8ee8f15cc9b8da1aa20f5784abfe54a576b3..c623778b36ba33ce9f1221c65cedcbac0c3ce064 100644 (file)
--- 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;