From a3e5e5797faad0db319d106afaa31b9020fac44f Mon Sep 17 00:00:00 2001 From: Dmytro Linkin Date: Wed, 23 Jun 2021 16:43:15 +0300 Subject: [PATCH] devlink: Protect rate list with lock while switching modes Devlink eswitch set command doesn't hold devlink->lock, which makes possible race condition between rate list traversing and others devlink rate KAPI calls, like devlink_rate_nodes_destroy(). Hold devlink lock while traversing the list. Fixes: a8ecb93ef03d ("devlink: Introduce rate nodes") Signed-off-by: Dmytro Linkin Reviewed-by: Parav Pandit Reviewed-by: Jiri Pirko Signed-off-by: David S. Miller --- net/core/devlink.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/core/devlink.c b/net/core/devlink.c index 153d432..8fdd04f 100644 --- a/net/core/devlink.c +++ b/net/core/devlink.c @@ -2710,11 +2710,15 @@ static int devlink_rate_nodes_check(struct devlink *devlink, u16 mode, { struct devlink_rate *devlink_rate; + /* Take the lock to sync with devlink_rate_nodes_destroy() */ + mutex_lock(&devlink->lock); list_for_each_entry(devlink_rate, &devlink->rate_list, list) if (devlink_rate_is_node(devlink_rate)) { + mutex_unlock(&devlink->lock); NL_SET_ERR_MSG_MOD(extack, "Rate node(s) exists."); return -EBUSY; } + mutex_unlock(&devlink->lock); return 0; } -- 2.7.4