4.16-stable review patch. If anyone has any objections, please let me know.
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From: Paolo Abeni pabeni@redhat.com
[ Upstream commit 69678bcd4d2dedbc3e8fcd6d7d99f283d83c531a ]
Damir reported a breakage of SO_BINDTODEVICE for UDP sockets. In absence of VRF devices, after commit fb74c27735f0 ("net: ipv4: add second dif to udp socket lookups") the dif mismatch isn't fatal anymore for UDP socket lookup with non null sk_bound_dev_if, breaking SO_BINDTODEVICE semantics.
This changeset addresses the issue making the dif match mandatory again in the above scenario.
Reported-by: Damir Mansurov dnman@oktetlabs.ru Fixes: fb74c27735f0 ("net: ipv4: add second dif to udp socket lookups") Fixes: 1801b570dd2a ("net: ipv6: add second dif to udp socket lookups") Signed-off-by: Paolo Abeni pabeni@redhat.com Acked-by: David Ahern dsahern@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv4/udp.c | 4 ++-- net/ipv6/udp.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-)
--- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -407,9 +407,9 @@ static int compute_score(struct sock *sk bool dev_match = (sk->sk_bound_dev_if == dif || sk->sk_bound_dev_if == sdif);
- if (exact_dif && !dev_match) + if (!dev_match) return -1; - if (sk->sk_bound_dev_if && dev_match) + if (sk->sk_bound_dev_if) score += 4; }
--- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -148,9 +148,9 @@ static int compute_score(struct sock *sk bool dev_match = (sk->sk_bound_dev_if == dif || sk->sk_bound_dev_if == sdif);
- if (exact_dif && !dev_match) + if (!dev_match) return -1; - if (sk->sk_bound_dev_if && dev_match) + if (sk->sk_bound_dev_if) score++; }