[PATCH v2] vdpa/ifc: fix null pointer dereference

[Andy Pei <andy.pei@intel.com>]

Fix null pointer dereference reported in coverity scan.

Coverity issue: 378882
Fixes: 5d75517beffe ("vdpa/ifc/base: access correct register for blk device")

Signed-off-by: Andy Pei <andy.pei@intel.com>
Acked-by: Xiao Wang <xiao.w.wang@intel.com>
---
 drivers/vdpa/ifc/base/ifcvf.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/vdpa/ifc/base/ifcvf.c b/drivers/vdpa/ifc/base/ifcvf.c
index dd475a7..0a9f71a 100644
--- a/drivers/vdpa/ifc/base/ifcvf.c
+++ b/drivers/vdpa/ifc/base/ifcvf.c
@@ -255,6 +255,10 @@
 	u32 ring_state;
 
 	cfg = hw->common_cfg;
+	if (!cfg) {
+		DEBUGOUT("common_cfg in HW is NULL.\n");
+		return;
+	}
 
 	IFCVF_WRITE_REG16(IFCVF_MSI_NO_VECTOR, &cfg->msix_config);
 	for (i = 0; i < hw->nr_vring; i++) {
@@ -262,6 +266,11 @@
 		IFCVF_WRITE_REG16(0, &cfg->queue_enable);
 		IFCVF_WRITE_REG16(IFCVF_MSI_NO_VECTOR, &cfg->queue_msix_vector);
 
+		if (!hw->lm_cfg) {
+			DEBUGOUT("live migration cfg in HW is NULL.\n");
+			continue;
+		}
+
 		if (hw->device_type == IFCVF_BLK)
 			ring_state = *(u32 *)(hw->lm_cfg +
 					IFCVF_LM_RING_STATE_OFFSET +
-- 
1.8.3.1