From: Moshe Shemesh <moshe@mellanox.com>
Date: Wed, 10 Oct 2018 16:09:25 +0300
Subject: devlink: Fix param set handling for string type
Patch-mainline: v4.19-rc8
Git-commit: f355cfcdb251e22b9dfb78c0eef4005a9d902a35
References: bsc#1109837

In case devlink param type is string, it needs to copy the string value
it got from the input to devlink_param_value.

Fixes: e3b7ca18ad7b ("devlink: Add param set command")
Signed-off-by: Moshe Shemesh <moshe@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 include/net/devlink.h |    2 +-
 net/core/devlink.c    |   11 ++++++++---
 2 files changed, 9 insertions(+), 4 deletions(-)

--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -311,7 +311,7 @@ union devlink_param_value {
 	u8 vu8;
 	u16 vu16;
 	u32 vu32;
-	const char *vstr;
+	char vstr[DEVLINK_PARAM_MAX_STRING_VALUE];
 	bool vbool;
 };
 
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -2999,6 +2999,8 @@ devlink_param_value_get_from_info(const
 				  struct genl_info *info,
 				  union devlink_param_value *value)
 {
+	int len;
+
 	if (param->type != DEVLINK_PARAM_TYPE_BOOL &&
 	    !info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA])
 		return -EINVAL;
@@ -3014,10 +3016,13 @@ devlink_param_value_get_from_info(const
 		value->vu32 = nla_get_u32(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]);
 		break;
 	case DEVLINK_PARAM_TYPE_STRING:
-		if (nla_len(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]) >
-		    DEVLINK_PARAM_MAX_STRING_VALUE)
+		len = strnlen(nla_data(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]),
+			      nla_len(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]));
+		if (len == nla_len(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]) ||
+		    len >= DEVLINK_PARAM_MAX_STRING_VALUE)
 			return -EINVAL;
-		value->vstr = nla_data(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]);
+		strcpy(value->vstr,
+		       nla_data(info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA]));
 		break;
 	case DEVLINK_PARAM_TYPE_BOOL:
 		value->vbool = info->attrs[DEVLINK_ATTR_PARAM_VALUE_DATA] ?