nvme: fix the dangerous reference of namespaces list

nvme_remove_namespaces and nvme_remove_invalid_namespaces reference
the ctrl->namespaces list w/o holding namespaces_mutext. It is ok
to invoke nvme_ns_remove there, but what if there is others.

To be safer, reference the ctrl->namespaces list under
namespaces_mutext.

Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jianchao Wang 2018-02-12 20:54:44 +08:00 committed by Jens Axboe
parent 9a915a5be7
commit 6f8e0d787e

View file

@ -3098,11 +3098,18 @@ static void nvme_remove_invalid_namespaces(struct nvme_ctrl *ctrl,
unsigned nsid)
{
struct nvme_ns *ns, *next;
LIST_HEAD(rm_list);
mutex_lock(&ctrl->namespaces_mutex);
list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) {
if (ns->head->ns_id > nsid)
nvme_ns_remove(ns);
list_move_tail(&ns->list, &rm_list);
}
mutex_unlock(&ctrl->namespaces_mutex);
list_for_each_entry_safe(ns, next, &rm_list, list)
nvme_ns_remove(ns);
}
static int nvme_scan_ns_list(struct nvme_ctrl *ctrl, unsigned nn)
@ -3202,6 +3209,7 @@ EXPORT_SYMBOL_GPL(nvme_queue_scan);
void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
{
struct nvme_ns *ns, *next;
LIST_HEAD(ns_list);
/*
* The dead states indicates the controller was not gracefully
@ -3212,7 +3220,11 @@ void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
if (ctrl->state == NVME_CTRL_DEAD)
nvme_kill_queues(ctrl);
list_for_each_entry_safe(ns, next, &ctrl->namespaces, list)
mutex_lock(&ctrl->namespaces_mutex);
list_splice_init(&ctrl->namespaces, &ns_list);
mutex_unlock(&ctrl->namespaces_mutex);
list_for_each_entry_safe(ns, next, &ns_list, list)
nvme_ns_remove(ns);
}
EXPORT_SYMBOL_GPL(nvme_remove_namespaces);