Subject: [PATCH 17/21] bnxt_en: Check for zero dir entries in NVRAM.

From: Vasundhara Volam <[email-masked]>
Date: Wed, 26 Aug 2020 01:08:33 -0400

[ Upstream commit dbbfa96ad920c50d58bcaefa57f5f33ceef9d00e ]

If firmware goes into unstable state, HWRM_NVM_GET_DIR_INFO firmware
command may return zero dir entries. Return error in such case to
avoid zero length dma buffer request.

Fixes: c0c050c58d84 ("bnxt_en: New Broadcom ethernet driver.")
Signed-off-by: Vasundhara Volam <[email-masked]>
Signed-off-by: Michael Chan <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index de9b34a255cf..fd01bcc8e28d 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -2161,6 +2161,9 @@ static int bnxt_get_nvram_directory(struct net_device *dev, u32 len, u8 *data)
 	if (rc != 0)
 		return rc;
 
+	if (!dir_entries || !entry_length)
+		return -EIO;
+
 	/* Insert 2 bytes of directory info (count and size of entries) */
 	if (len < 2)
 		return -EINVAL;
-- 
2.26.2