octeontx2-pf: handle otx2_mbox_get_rsp errors in otx2_flows.c

Adding error pointer check after calling otx2_mbox_get_rsp().

Fixes: 9917060 ("octeontx2-pf: Cleanup flow rule management")
Fixes: f0a1913 ("octeontx2-pf: Add support for ethtool ntuple filters")
Fixes: 674b3e1 ("octeontx2-pf: Add additional checks while configuring ucast/bcast/mcast rules")
Signed-off-by: Dipendra Khadka <kdipendra88@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>

drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c

@@ -119,6 +119,8 @@ int otx2_alloc_mcam_entries(struct otx2_nic *pfvf, u16 count)
 
 		rsp = (struct npc_mcam_alloc_entry_rsp *)otx2_mbox_get_rsp
 			(&pfvf->mbox.mbox, 0, &req->hdr);
+		if (IS_ERR(rsp))
+			goto exit;
 
 		for (ent = 0; ent < rsp->count; ent++)
 			flow_cfg->flow_ent[ent + allocated] = rsp->entry_list[ent];
@@ -197,6 +199,10 @@ int otx2_mcam_entry_init(struct otx2_nic *pfvf)
 
 	rsp = (struct npc_mcam_alloc_entry_rsp *)otx2_mbox_get_rsp
 	       (&pfvf->mbox.mbox, 0, &req->hdr);
+	if (IS_ERR(rsp)) {
+		mutex_unlock(&pfvf->mbox.lock);
+		return PTR_ERR(rsp);
+	}
 
 	if (rsp->count != req->count) {
 		netdev_info(pfvf->netdev,
@@ -232,6 +238,10 @@ int otx2_mcam_entry_init(struct otx2_nic *pfvf)
 
 	frsp = (struct npc_get_field_status_rsp *)otx2_mbox_get_rsp
 	       (&pfvf->mbox.mbox, 0, &freq->hdr);
+	if (IS_ERR(frsp)) {
+		mutex_unlock(&pfvf->mbox.lock);
+		return PTR_ERR(frsp);
+	}
 
 	if (frsp->enable) {
 		pfvf->flags |= OTX2_FLAG_RX_VLAN_SUPPORT;