From: Kuniyuki Iwashima The next patch will replace __dev_get_by_index() and __dev_get_by_flags() to RCU + refcount version. Then, we will need to call dev_put() in some error paths. Let's unify two error paths to make the next patch cleaner. Note that we add READ_ONCE() for net->ipv6.devconf_all->forwarding and idev->conf.forwarding as we will drop RTNL that protects them. Signed-off-by: Kuniyuki Iwashima Reviewed-by: Eric Dumazet --- v3: Use READ_ONCE() for net->ipv6.devconf_all->forwarding and idev->conf.forwarding --- net/ipv6/anycast.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) diff --git a/net/ipv6/anycast.c b/net/ipv6/anycast.c index 8440e7b27f6d..fd3d104c6c05 100644 --- a/net/ipv6/anycast.c +++ b/net/ipv6/anycast.c @@ -67,12 +67,11 @@ static u32 inet6_acaddr_hash(const struct net *net, int ipv6_sock_ac_join(struct sock *sk, int ifindex, const struct in6_addr *addr) { struct ipv6_pinfo *np = inet6_sk(sk); + struct ipv6_ac_socklist *pac = NULL; + struct net *net = sock_net(sk); struct net_device *dev = NULL; struct inet6_dev *idev; - struct ipv6_ac_socklist *pac; - struct net *net = sock_net(sk); - int ishost = !net->ipv6.devconf_all->forwarding; - int err = 0; + int err = 0, ishost; ASSERT_RTNL(); @@ -84,15 +83,22 @@ int ipv6_sock_ac_join(struct sock *sk, int ifindex, const struct in6_addr *addr) if (ifindex) dev = __dev_get_by_index(net, ifindex); - if (ipv6_chk_addr_and_flags(net, addr, dev, true, 0, IFA_F_TENTATIVE)) - return -EINVAL; + if (ipv6_chk_addr_and_flags(net, addr, dev, true, 0, IFA_F_TENTATIVE)) { + err = -EINVAL; + goto error; + } pac = sock_kmalloc(sk, sizeof(struct ipv6_ac_socklist), GFP_KERNEL); - if (!pac) - return -ENOMEM; + if (!pac) { + err = -ENOMEM; + goto error; + } + pac->acl_next = NULL; pac->acl_addr = *addr; + ishost = !READ_ONCE(net->ipv6.devconf_all->forwarding); + if (ifindex == 0) { struct rt6_info *rt; @@ -123,8 +129,9 @@ int ipv6_sock_ac_join(struct sock *sk, int ifindex, const struct in6_addr *addr) err = -EADDRNOTAVAIL; goto error; } + /* reset ishost, now that we have a specific device */ - ishost = !idev->cnf.forwarding; + ishost = !READ_ONCE(idev->cnf.forwarding); pac->acl_ifindex = dev->ifindex; -- 2.49.0