[PATCH v4 05/14] crypto: dh - fix memleak in setkey

[Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>]

setkey can be called multiple times during the existence
of the transformation object. In case of multiple setkey calls,
the old key was not freed and we leaked memory.
Free the old MPI key if any.

Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
---
 crypto/dh.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/crypto/dh.c b/crypto/dh.c
index 7cec0498..e151f12 100644
--- a/crypto/dh.c
+++ b/crypto/dh.c
@@ -85,6 +85,9 @@ static int dh_set_secret(struct crypto_kpp *tfm, const void *buf,
 	struct dh_ctx *ctx = dh_get_ctx(tfm);
 	struct dh params;
 
+	/* Free the old MPI key if any */
+	dh_free_ctx(ctx);
+
 	if (crypto_dh_decode_key(buf, len, &params) < 0)
 		return -EINVAL;
 
-- 
2.7.4