[PATCH net-next v02 1/2] af_packet: allow fanout_add when socket is not RUNNING

[Gur Stavi]

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.st...@huawei.com>
---
 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) {
                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