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 ddc47e4404b58f03e98345398fb12d38fe291512 upstream.
When we do tunnel or beet mode, we pass saddr and daddr from the template to xfrm_state_find(), this is ok. On transport mode, we pass the addresses from the flowi, assuming that the IP addresses (and address family) don't change during transformation. This assumption is wrong in the IPv4 mapped IPv6 case, packet is IPv4 and template is IPv6.
Fix this by catching address family missmatches of the policy and the flow already before we do the lookup.
Reported-by: syzbot syzkaller@googlegroups.com Signed-off-by: Steffen Klassert steffen.klassert@secunet.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/xfrm/xfrm_policy.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
--- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -1257,9 +1257,15 @@ static struct xfrm_policy *xfrm_sk_polic again: pol = rcu_dereference(sk->sk_policy[dir]); if (pol != NULL) { - bool match = xfrm_selector_match(&pol->selector, fl, family); + bool match; int err = 0;
+ if (pol->family != family) { + pol = NULL; + goto out; + } + + match = xfrm_selector_match(&pol->selector, fl, family); if (match) { if ((sk->sk_mark & pol->mark.m) != pol->mark.v) { pol = NULL;