xfrm: Copy policy family in clone_policy

The syzbot found an ancient bug in the IPsec code.  When we cloned
a socket policy (for example, for a child TCP socket derived from a
listening socket), we did not copy the family field.  This results
in a live policy with a zero family field.  This triggers a BUG_ON
check in the af_key code when the cloned policy is retrieved.

This patch fixes it by copying the family field over.

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 6eb228a..2a60938 100644 (file)
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -1306,6 +1306,7 @@ static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
                newp->xfrm_nr = old->xfrm_nr;
                newp->index = old->index;
                newp->type = old->type;
+               newp->family = old->family;
                memcpy(newp->xfrm_vec, old->xfrm_vec,
                       newp->xfrm_nr*sizeof(struct xfrm_tmpl));
                spin_lock_bh(&net->xfrm.xfrm_policy_lock);