4.9-stable review patch. If anyone has any objections, please let me know.
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From: Steffen Klassert steffen.klassert@secunet.com
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 steffen.klassert@secunet.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/xfrm/xfrm_state.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/net/xfrm/xfrm_state.c +++ b/net/xfrm/xfrm_state.c @@ -1883,6 +1883,11 @@ int xfrm_user_policy(struct sock *sk, in 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);