[PATCH] Staging: net: nic: Add error pointer check in otx2_flows.c

[Dipendra Khadka <kdipendra88@gmail.com>]

Smatch reported following:
'''
drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c:123 otx2_alloc_mcam_entries() error: 'rsp' dereferencing possible ERR_PTR()
drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c:201 otx2_mcam_entry_init() error: 'rsp' dereferencing possible ERR_PTR()
drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c:236 otx2_mcam_entry_init() error: 'frsp' dereferencing possible ERR_PTR()
'''

Adding error pointer check after calling otx2_mbox_get_rsp.

Signed-off-by: Dipendra Khadka <kdipendra88@gmail.com>
---
 .../ethernet/marvell/octeontx2/nic/otx2_flows.c   | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
index 98c31a16c70b..4b61236c7c41 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
@@ -120,6 +120,11 @@ 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)) {
+			mutex_unlock(&bfvf->mbox.lock);
+			return PTR_ERR(rsp);
+		}
+
 		for (ent = 0; ent < rsp->count; ent++)
 			flow_cfg->flow_ent[ent + allocated] = rsp->entry_list[ent];
 
@@ -198,6 +203,11 @@ 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(&bfvf->mbox.lock);
+		return PTR_ERR(rsp);
+	}
+
 	if (rsp->count != req->count) {
 		netdev_info(pfvf->netdev,
 			    "Unable to allocate MCAM entries for ucast, vlan and vf_vlan\n");
@@ -233,6 +243,11 @@ 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;
 		pfvf->flags |= OTX2_FLAG_VF_VLAN_SUPPORT;
-- 
2.43.0