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.
Socket can be RUNNING if it has a specified protocol. Either directly from packet_create (being implicitly bound to any interface) or following a successful bind. Socket RUNNING state is switched off if it is bound to an interface that went down.
Instead of the test for RUNNING, this patch adds a test that socket can become RUNNING.
Signed-off-by: Gur Stavi gur.stavi@huawei.com --- net/packet/af_packet.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index f8942062f776..2ff4b251842d 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1846,21 +1846,22 @@ 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) && + if (po->num && match->type == type && match->prot_hook.type == po->prot_hook.type && match->prot_hook.dev == po->prot_hook.dev) { 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; } }