[PATCH] nvmet-auth: Synchronize timeout work during SQ teardown

[Kazuki Hanai <hnkz.64@gmail.com>]

nvmet_auth_sq_free() cancels auth_expired_work with
cancel_delayed_work(). If the work has already started, cancellation does
not wait for the callback. Transport teardown can consequently free or
reuse the queue containing struct nvmet_sq while
nvmet_auth_expired_work() still accesses that SQ.

Add a teardown-specific helper that synchronously drains the delayed work
before freeing authentication state, and use it from nvmet_sq_destroy().
Keep the non-synchronous helper for in-band authentication state cleanup,
where the SQ owner remains alive.

Fixes: 1a70200f404a ("nvmet-auth: expire authentication sessions")
Cc: stable@vger.kernel.org
Signed-off-by: Kazuki Hanai <hnkz.64@gmail.com>
---
 drivers/nvme/target/auth.c  | 6 ++++++
 drivers/nvme/target/core.c  | 2 +-
 drivers/nvme/target/nvmet.h | 2 ++
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/target/auth.c b/drivers/nvme/target/auth.c
index edb9627d97b09..a55319bcdbd13 100644
--- a/drivers/nvme/target/auth.c
+++ b/drivers/nvme/target/auth.c
@@ -238,6 +238,12 @@ void nvmet_auth_sq_free(struct nvmet_sq *sq)
 	sq->dhchap_skey = NULL;
 }
 
+void nvmet_auth_sq_destroy(struct nvmet_sq *sq)
+{
+	cancel_delayed_work_sync(&sq->auth_expired_work);
+	nvmet_auth_sq_free(sq);
+}
+
 void nvmet_destroy_auth(struct nvmet_ctrl *ctrl)
 {
 	ctrl->shash_id = 0;
diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index d74c01c98f194..4b48ca78ce5a8 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -980,7 +980,7 @@ void nvmet_sq_destroy(struct nvmet_sq *sq)
 	wait_for_completion(&sq->confirm_done);
 	wait_for_completion(&sq->free_done);
 	percpu_ref_exit(&sq->ref);
-	nvmet_auth_sq_free(sq);
+	nvmet_auth_sq_destroy(sq);
 	nvmet_cq_put(sq->cq);
 
 	/*
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index e362d7913a380..dbda55895f4fb 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -924,6 +924,7 @@ u8 nvmet_setup_auth(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq, bool reset);
 void nvmet_auth_sq_init(struct nvmet_sq *sq);
 void nvmet_destroy_auth(struct nvmet_ctrl *ctrl);
 void nvmet_auth_sq_free(struct nvmet_sq *sq);
+void nvmet_auth_sq_destroy(struct nvmet_sq *sq);
 int nvmet_setup_dhgroup(struct nvmet_ctrl *ctrl, u8 dhgroup_id);
 bool nvmet_check_auth_status(struct nvmet_req *req);
 int nvmet_auth_host_hash(struct nvmet_req *req, u8 *response,
@@ -950,6 +951,7 @@ static inline void nvmet_auth_sq_init(struct nvmet_sq *sq)
 }
 static inline void nvmet_destroy_auth(struct nvmet_ctrl *ctrl) {};
 static inline void nvmet_auth_sq_free(struct nvmet_sq *sq) {};
+static inline void nvmet_auth_sq_destroy(struct nvmet_sq *sq) {};
 static inline bool nvmet_check_auth_status(struct nvmet_req *req)
 {
 	return true;