Gur Stavi wrote:
> PACKET socket can retain its fanout membership through link down and up
> and leave a fanout while closed regardless of link state.
> However, socket was forbidden from joining a fanout while it was not
> RUNNING.
>
> This patch allows PACKET socket to join fanout while not RUNNING.
>
> Signed-off-by: Gur Stavi <gur.stavi@xxxxxxxxxx>
> ---
> net/packet/af_packet.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
> index f8942062f776..fb2cca73d953 100644
> --- a/net/packet/af_packet.c
> +++ b/net/packet/af_packet.c
> @@ -1846,21 +1846,21 @@ static int fanout_add(struct sock *sk, struct fanout_args *args)
> err = -EINVAL;
>
> spin_lock(&po->bind_lock);
> - if (packet_sock_flag(po, PACKET_SOCK_RUNNING) &&
> - match->type == type &&
> + if (match->type == type &&
> match->prot_hook.type == po->prot_hook.type &&
> match->prot_hook.dev == po->prot_hook.dev) {
Remaining unaddressed issue is that the socket can now be added
before being bound. See comment in v1.
> err = -ENOSPC;
> if (refcount_read(&match->sk_ref) < match->max_num_members) {
> - __dev_remove_pack(&po->prot_hook);
> -
> /* Paired with packet_setsockopt(PACKET_FANOUT_DATA) */
> WRITE_ONCE(po->fanout, match);
>
> po->rollover = rollover;
> rollover = NULL;
> refcount_set(&match->sk_ref, refcount_read(&match->sk_ref) + 1);
> - __fanout_link(sk, po);
> + if (packet_sock_flag(po, PACKET_SOCK_RUNNING)) {
> + __dev_remove_pack(&po->prot_hook);
> + __fanout_link(sk, po);
> + }
> err = 0;
> }
> }
> --
> 2.45.2
>
