[PATCH net 1/3] devlink: Fix param set handling for string type

[Moshe Shemesh]

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@xxxxxxxxxxxx>
---
 include/net/devlink.h |  2 +-
 net/core/devlink.c    | 11 ++++++++---
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/include/net/devlink.h b/include/net/devlink.h
index b9b89d6..b0e17c0 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -311,7 +311,7 @@ enum devlink_param_type {
 	u8 vu8;
 	u16 vu16;
 	u32 vu32;
-	const char *vstr;
+	char vstr[DEVLINK_PARAM_MAX_STRING_VALUE];
 	bool vbool;
 };
 
diff --git a/net/core/devlink.c b/net/core/devlink.c
index 8c0ed22..d808af7 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -2995,6 +2995,8 @@ static int devlink_nl_cmd_param_get_dumpit(struct sk_buff *msg,
 				  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;
@@ -3010,10 +3012,13 @@ static int devlink_nl_cmd_param_get_dumpit(struct sk_buff *msg,
 		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] ?
-- 
1.8.3.1