From: Michael Chan <michael.chan@broadcom.com>
Date: Thu, 26 Oct 2017 11:51:22 -0400
Subject: bnxt_en: Check for zero length value in bnxt_get_nvram_item().
Patch-mainline: v4.15-rc1
Git-commit: e0ad8fc5980b362028cfd63ec037f4b491e726c6
References: bsc#1050242 FATE#322914

Return -EINVAL if the length is zero and not proceed to do essentially
nothing.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -1773,6 +1773,9 @@ static int bnxt_get_nvram_item(struct ne
 	dma_addr_t dma_handle;
 	struct hwrm_nvm_read_input req = {0};
 
+	if (!length)
+		return -EINVAL;
+
 	buf = dma_alloc_coherent(&bp->pdev->dev, length, &dma_handle,
 				 GFP_KERNEL);
 	if (!buf) {