[PATCH AUTOSEL 4.19 177/205] soc: qcom: apr: Avoid string overflow

[Sasha Levin]

From: Niklas Cassel <niklas.cassel@xxxxxxxxxx>

[ Upstream commit 4fadb26574cb74e5de079dd384f25f44f4fb3ec3 ]

'adev->name' is used as a NUL-terminated string, but using strncpy() with the
length equal to the buffer size may result in lack of the termination:

In function 'apr_add_device',
    inlined from 'of_register_apr_devices' at drivers//soc/qcom/apr.c:264:7,
    inlined from 'apr_probe' at drivers//soc/qcom/apr.c:290:2:
drivers//soc/qcom/apr.c:222:3: warning: 'strncpy' specified bound 32 equals destination size [-Wstringop-truncation]
   strncpy(adev->name, np->name, APR_NAME_SIZE);
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This changes it to use the safer strscpy() instead.

Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxxxx>
Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Signed-off-by: Andy Gross <andy.gross@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/soc/qcom/apr.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/soc/qcom/apr.c b/drivers/soc/qcom/apr.c
index 57af8a5373325..ee9197f5aae96 100644
--- a/drivers/soc/qcom/apr.c
+++ b/drivers/soc/qcom/apr.c
@@ -219,9 +219,9 @@ static int apr_add_device(struct device *dev, struct device_node *np,
 	adev->domain_id = id->domain_id;
 	adev->version = id->svc_version;
 	if (np)
-		strncpy(adev->name, np->name, APR_NAME_SIZE);
+		strscpy(adev->name, np->name, APR_NAME_SIZE);
 	else
-		strncpy(adev->name, id->name, APR_NAME_SIZE);
+		strscpy(adev->name, id->name, APR_NAME_SIZE);
 
 	dev_set_name(&adev->dev, "aprsvc:%s:%x:%x", adev->name,
 		     id->domain_id, id->svc_id);
-- 
2.20.1