xfrm: Refuse to insert 32 bit userspace socket policies on 64 bit systems

We don't have a compat layer for xfrm, so userspace and kernel
structures have different sizes in this case. This results in
a broken configuration, so refuse to configure socket policies
when trying to insert from 32 bit userspace as we do it already
with policies inserted via netlink.

Reported-and-tested-by: syzbot+e1a1577ca8bcb47b769a@syzkaller.appspotmail.com
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This commit is contained in:
Steffen Klassert 2018-02-01 08:49:23 +01:00
parent 743ffffefa
commit 19d7df69fd

View File

@ -2056,6 +2056,11 @@ int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen
struct xfrm_mgr *km;
struct xfrm_policy *pol = NULL;
#ifdef CONFIG_COMPAT
if (in_compat_syscall())
return -EOPNOTSUPP;
#endif
if (!optval && !optlen) {
xfrm_sk_policy_insert(sk, XFRM_POLICY_IN, NULL);
xfrm_sk_policy_insert(sk, XFRM_POLICY_OUT, NULL);