Subject: [PATCH AUTOSEL 4.19 047/205] i40e: use correct length for strncpy

From: Sasha Levin <[email-masked]>
Date: Fri, 8 Nov 2019 06:35:14 -0500

From: Mitch Williams <[email-masked]>

[ Upstream commit 7eb74ff891b4e94b8bac48f648a21e4b94ddee64 ]

Caught by GCC 8. When we provide a length for strncpy, we should not
include the terminating null. So we must tell it one less than the size
of the destination buffer.

Signed-off-by: Mitch Williams <[email-masked]>
Tested-by: Andrew Bowers <[email-masked]>
Signed-off-by: Jeff Kirsher <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 drivers/net/ethernet/intel/i40e/i40e_ptp.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_ptp.c b/drivers/net/ethernet/intel/i40e/i40e_ptp.c
index 35f2866b38c6b..1199f0502d6d5 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ptp.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ptp.c
@@ -694,7 +694,8 @@ static long i40e_ptp_create_clock(struct i40e_pf *pf)
 	if (!IS_ERR_OR_NULL(pf->ptp_clock))
 		return 0;
 
-	strncpy(pf->ptp_caps.name, i40e_driver_name, sizeof(pf->ptp_caps.name));
+	strncpy(pf->ptp_caps.name, i40e_driver_name,
+		sizeof(pf->ptp_caps.name) - 1);
 	pf->ptp_caps.owner = THIS_MODULE;
 	pf->ptp_caps.max_adj = 999999999;
 	pf->ptp_caps.n_ext_ts = 0;
-- 
2.20.1