xfrm_user: fix info leak in copy_to_user_auth()
[ Upstream commit 4c87308bdea31a7b4828a51f6156e6f721a1fcc9 ]
copy_to_user_auth() fails to initialize the remainder of alg_name and
therefore discloses up to 54 bytes of heap memory via netlink to
userland.
Use strncpy() instead of strcpy() to fill the trailing bytes of alg_name
with null bytes.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 4cae47d..f5936d8 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -742,7 +742,7 @@
return -EMSGSIZE;
algo = nla_data(nla);
- strcpy(algo->alg_name, auth->alg_name);
+ strncpy(algo->alg_name, auth->alg_name, sizeof(algo->alg_name));
memcpy(algo->alg_key, auth->alg_key, (auth->alg_key_len + 7) / 8);
algo->alg_key_len = auth->alg_key_len;