From: Steffen Klassert Date: Thu, 1 Feb 2018 07:49:23 +0000 (+0100) Subject: xfrm: Refuse to insert 32 bit userspace socket policies on 64 bit systems X-Git-Tag: v3.18.103~42 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=6be3251dafdc2a75afee5241dc9b2bde91c4ebc2;p=thirdparty%2Fkernel%2Fstable.git xfrm: Refuse to insert 32 bit userspace socket policies on 64 bit systems commit 19d7df69fdb2636856dc8919de72fc1bf8f79598 upstream. 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 [use is_compat_task() - gregkh] Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c index 60e04edc4963c..431f512f6bded 100644 --- a/net/xfrm/xfrm_state.c +++ b/net/xfrm/xfrm_state.c @@ -1845,6 +1845,11 @@ 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 (is_compat_task()) + return -EOPNOTSUPP; +#endif + if (!optval && !optlen) { xfrm_sk_policy_insert(sk, XFRM_POLICY_IN, NULL); xfrm_sk_policy_insert(sk, XFRM_POLICY_OUT, NULL);