[PATCH net-next 2/2] devlink: Protect devlink port list traversal

[Parav Pandit <parav@mellanox.com>]

From: Parav Pandit <parav@nvidia.com>

Cited patch in fixes tag misses to protect port list traversal
while traversing per port reporter list.

Protect it using devlink instance lock.

Fixes: f4f541660121 ("devlink: Implement devlink health reporters on per-port basis")
Signed-off-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
---
 net/core/devlink.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 9b01f7245fd8..58c8bb07fa19 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -5895,6 +5895,7 @@ devlink_nl_cmd_health_reporter_get_dumpit(struct sk_buff *msg,
 	list_for_each_entry(devlink, &devlink_list, list) {
 		if (!net_eq(devlink_net(devlink), sock_net(msg->sk)))
 			continue;
+		mutex_lock(&devlink->lock);
 		list_for_each_entry(port, &devlink->port_list, list) {
 			mutex_lock(&port->reporters_lock);
 			list_for_each_entry(reporter, &port->reporter_list, list) {
@@ -5909,12 +5910,14 @@ devlink_nl_cmd_health_reporter_get_dumpit(struct sk_buff *msg,
 								      NLM_F_MULTI);
 				if (err) {
 					mutex_unlock(&port->reporters_lock);
+					mutex_unlock(&devlink->lock);
 					goto out;
 				}
 				idx++;
 			}
 			mutex_unlock(&port->reporters_lock);
 		}
+		mutex_unlock(&devlink->lock);
 	}
 out:
 	mutex_unlock(&devlink_mutex);
-- 
2.26.2