Fix a possible NULL pointer dereference when trying to read hwmon sysfs entries associated to NVMe-oF devices that were hot-removed or disconnected.
Unregister the NVMe hwmon device upon controller teardown (nvme_stop_ctrl()). Signed-off-by: Enzo Matsumiya <ematsum...@suse.de> --- drivers/nvme/host/core.c | 1 + drivers/nvme/host/hwmon.c | 8 ++++++++ drivers/nvme/host/nvme.h | 2 ++ 3 files changed, 11 insertions(+) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 9a270e49df17..becc80a0c3b8 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -4344,6 +4344,7 @@ EXPORT_SYMBOL_GPL(nvme_complete_async_event); void nvme_stop_ctrl(struct nvme_ctrl *ctrl) { + nvme_hwmon_exit(ctrl); nvme_mpath_stop(ctrl); nvme_stop_keep_alive(ctrl); flush_work(&ctrl->async_event_work); diff --git a/drivers/nvme/host/hwmon.c b/drivers/nvme/host/hwmon.c index 552dbc04567b..7f62cca4c577 100644 --- a/drivers/nvme/host/hwmon.c +++ b/drivers/nvme/host/hwmon.c @@ -71,6 +71,9 @@ static int nvme_hwmon_read(struct device *dev, enum hwmon_sensor_types type, int temp; int err; + if (data->ctrl->state != NVME_CTRL_LIVE) + return -EAGAIN; + /* * First handle attributes which don't require us to read * the smart log. @@ -253,3 +256,8 @@ int nvme_hwmon_init(struct nvme_ctrl *ctrl) return 0; } + +void nvme_hwmon_exit(struct nvme_ctrl *ctrl) +{ + hwmon_device_unregister(ctrl->dev); +} diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h index 567f7ad18a91..621e9b1575f6 100644 --- a/drivers/nvme/host/nvme.h +++ b/drivers/nvme/host/nvme.h @@ -807,11 +807,13 @@ static inline struct nvme_ns *nvme_get_ns_from_dev(struct device *dev) #ifdef CONFIG_NVME_HWMON int nvme_hwmon_init(struct nvme_ctrl *ctrl); +void nvme_hwmon_exit(struct nvme_ctrl *ctrl); #else static inline int nvme_hwmon_init(struct nvme_ctrl *ctrl) { return 0; } +static inline void nvme_hwmon_exit(struct nvme_ctrl *ctrl) { } #endif u32 nvme_command_effects(struct nvme_ctrl *ctrl, struct nvme_ns *ns, -- 2.29.2