[PATCH AUTOSEL for 4.4 007/167] af_key: Fix slab-out-of-bounds in pfkey_compile_policy.

Sasha Levin
2018-03-19T17:35:55Z

From: Steffen Klassert <steffen.klassert@secunet.com>

[ Upstream commit d90c902449a7561f1b1d58ba5a0d11728ce8b0b2 ]

The sadb_x_sec_len is stored in the unit 'byte divided by eight'.
So we have to multiply this value by eight before we can do
size checks. Otherwise we may get a slab-out-of-bounds when
we memcpy the user sec_ctx.

Fixes: df71837d502 ("[LSM-IPSec]: Security association restriction.")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
net/key/af_key.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/key/af_key.c b/net/key/af_key.c
index 6482b001f19a..15150b412930 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -3305,7 +3305,7 @@ static struct xfrm_policy *pfkey_compile_policy(struct sock *sk, int opt,
p += pol->sadb_x_policy_len*8;
sec_ctx = (struct sadb_x_sec_ctx *)p;
if (len < pol->sadb_x_policy_len*8 +
- sec_ctx->sadb_x_sec_len) {
+ sec_ctx->sadb_x_sec_len*8) {
*dir = -EINVAL;
goto out;
}
--
2.14.1