4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Ahern <dsahern@xxxxxxxxx> [ Upstream commit d4a7e9bb74b5aaf07b89f6531c080b1130bdf019 ] I realized the last patch calls dev_get_by_index_rcu in a branch not holding the rcu lock. Add the calls to rcu_read_lock and rcu_read_unlock. Fixes: ec90ad334986 ("ipv6: Consider sk_bound_dev_if when binding a socket to a v4 mapped address") Signed-off-by: David Ahern <dsahern@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ipv6/af_inet6.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -317,17 +317,20 @@ int inet6_bind(struct socket *sock, stru goto out; } + rcu_read_lock(); if (sk->sk_bound_dev_if) { dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if); if (!dev) { err = -ENODEV; - goto out; + goto out_unlock; } } /* Reproduce AF_INET checks to make the bindings consistent */ v4addr = addr->sin6_addr.s6_addr32[3]; chk_addr_ret = inet_addr_type_dev_table(net, dev, v4addr); + rcu_read_unlock(); + if (!net->ipv4.sysctl_ip_nonlocal_bind && !(inet->freebind || inet->transparent) && v4addr != htonl(INADDR_ANY) &&