[PATCH v2 3/8] qedi: Fix list_del corruption while removing active IO

[Manish Rangankar <mrangankar@xxxxxxxxxxx>]

From: Nilesh Javali <njavali@xxxxxxxxxxx>

While aborting the IO, the FW cleanup task timed out and driver
deleted the IO from active command list. Some time later, the FW
sends the cleanup task response and driver again deletes the IO
from active command list causing FW to send IO completion for
non-existent IO and list_del corruption of active command list.

Add fix to check if IO is present before deleting the i/o from active
command list ensuring FW sends valid i/o completion and protect the
list_del corruption.

Signed-off-by: Nilesh Javali <njavali@xxxxxxxxxxx>
Signed-off-by: Manish Rangankar <mrangankar@xxxxxxxxxxx>
---
 drivers/scsi/qedi/qedi_fw.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/qedi/qedi_fw.c b/drivers/scsi/qedi/qedi_fw.c
index 6ed74583b1b9..34c477bda8a4 100644
--- a/drivers/scsi/qedi/qedi_fw.c
+++ b/drivers/scsi/qedi/qedi_fw.c
@@ -816,8 +816,11 @@ static void qedi_process_cmd_cleanup_resp(struct qedi_ctx *qedi,
 			qedi_clear_task_idx(qedi_conn->qedi, rtid);
 
 			spin_lock(&qedi_conn->list_lock);
-			list_del_init(&dbg_cmd->io_cmd);
-			qedi_conn->active_cmd_count--;
+			if (likely(dbg_cmd->io_cmd_in_list)) {
+				dbg_cmd->io_cmd_in_list = false;
+				list_del_init(&dbg_cmd->io_cmd);
+				qedi_conn->active_cmd_count--;
+			}
 			spin_unlock(&qedi_conn->list_lock);
 			qedi_cmd->state = CLEANUP_RECV;
 			wake_up_interruptible(&qedi_conn->wait_queue);
@@ -1235,6 +1238,7 @@ int qedi_cleanup_all_io(struct qedi_ctx *qedi, struct qedi_conn *qedi_conn,
 		qedi_conn->cmd_cleanup_req++;
 		qedi_iscsi_cleanup_task(ctask, true);
 
+		cmd->io_cmd_in_list = false;
 		list_del_init(&cmd->io_cmd);
 		qedi_conn->active_cmd_count--;
 		QEDI_WARN(&qedi->dbg_ctx,
@@ -1446,8 +1450,11 @@ static void qedi_tmf_work(struct work_struct *work)
 	spin_unlock_bh(&qedi_conn->tmf_work_lock);
 
 	spin_lock(&qedi_conn->list_lock);
-	list_del_init(&cmd->io_cmd);
-	qedi_conn->active_cmd_count--;
+	if (likely(cmd->io_cmd_in_list)) {
+		cmd->io_cmd_in_list = false;
+		list_del_init(&cmd->io_cmd);
+		qedi_conn->active_cmd_count--;
+	}
 	spin_unlock(&qedi_conn->list_lock);
 
 	clear_bit(QEDI_CONN_FW_CLEANUP, &qedi_conn->flags);
-- 
2.25.0