[PATCH net] nfp: flower: verify that block cb is not busy before binding

[Vlad Buslov]

When processing FLOW_BLOCK_BIND command on indirect block, check that flow
block cb is not busy.

Fixes: 0d4fd02e7199 ("net: flow_offload: add flow_block_cb_is_busy() and use 
it")
Reported-by: Jakub Kicinski <jakub.kicin...@netronome.com>
Signed-off-by: Vlad Buslov <vla...@mellanox.com>
---
 drivers/net/ethernet/netronome/nfp/flower/offload.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/net/ethernet/netronome/nfp/flower/offload.c 
b/drivers/net/ethernet/netronome/nfp/flower/offload.c
index e209f150c5f2..9917d64694c6 100644
--- a/drivers/net/ethernet/netronome/nfp/flower/offload.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/offload.c
@@ -1416,6 +1416,13 @@ nfp_flower_setup_indr_tc_block(struct net_device 
*netdev, struct nfp_app *app,
 
        switch (f->command) {
        case FLOW_BLOCK_BIND:
+               cb_priv = nfp_flower_indr_block_cb_priv_lookup(app, netdev);
+               if (cb_priv &&
+                   flow_block_cb_is_busy(nfp_flower_setup_indr_block_cb,
+                                         cb_priv,
+                                         &nfp_block_cb_list))
+                       return -EBUSY;
+
                cb_priv = kmalloc(sizeof(*cb_priv), GFP_KERNEL);
                if (!cb_priv)
                        return -ENOMEM;
-- 
2.21.0