From e73574f7bc9b83f290fbc7760a9153e05133cbf3 Mon Sep 17 00:00:00 2001 From: Israel Rukshin Date: Wed, 6 Oct 2021 08:09:43 +0000 Subject: [PATCH] nvmet: fix use-after-free when a port is removed [ Upstream commit e3e19dcc4c416d65f99f13d55be2b787f8d0050e ] When a port is removed through configfs, any connected controllers are starting teardown flow asynchronously and can still send commands. This causes a use-after-free bug for any command that dereferences req->port (like in nvmet_parse_io_cmd). To fix this, wait for all the teardown scheduled works to complete (like release_work at rdma/tcp drivers). This ensures there are no active controllers when the port is eventually removed. Signed-off-by: Israel Rukshin Reviewed-by: Max Gurtovoy Signed-off-by: Christoph Hellwig Signed-off-by: Sasha Levin --- drivers/nvme/target/configfs.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c index 37e1d77..9aed5cc 100644 --- a/drivers/nvme/target/configfs.c +++ b/drivers/nvme/target/configfs.c @@ -1462,6 +1462,8 @@ static void nvmet_port_release(struct config_item *item) { struct nvmet_port *port = to_nvmet_port(item); + /* Let inflight controllers teardown complete */ + flush_scheduled_work(); list_del(&port->global_entry); kfree(port->ana_state); -- 2.7.4