net: qlogic: check the return value of dma_alloc_coherent() in qed_vf_hw_prepare()

The function dma_alloc_coherent() in qed_vf_hw_prepare() can fail, so
its return value should be checked.

Fixes: 1408cc1f ("qed: Introduce VFs")
Reported-by: NTOTE Robot <oslab@tsinghua.edu.cn>
Signed-off-by: NJia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/qlogic/qed/qed_vf.c

@@ -513,6 +513,9 @@ int qed_vf_hw_prepare(struct qed_hwfn *p_hwfn)
 						    p_iov->bulletin.size,
 						    &p_iov->bulletin.phys,
 						    GFP_KERNEL);
+	if (!p_iov->bulletin.p_virt)
+		goto free_pf2vf_reply;
+
 	DP_VERBOSE(p_hwfn, QED_MSG_IOV,
 		   "VF's bulletin Board [%p virt 0x%llx phys 0x%08x bytes]\n",
 		   p_iov->bulletin.p_virt,
@@ -552,6 +555,10 @@ int qed_vf_hw_prepare(struct qed_hwfn *p_hwfn)
 
 	return rc;
 
+free_pf2vf_reply:
+	dma_free_coherent(&p_hwfn->cdev->pdev->dev,
+			  sizeof(union pfvf_tlvs),
+			  p_iov->pf2vf_reply, p_iov->pf2vf_reply_phys);
 free_vf2pf_request:
 	dma_free_coherent(&p_hwfn->cdev->pdev->dev,
 			  sizeof(union vfpf_tlvs),