[PATCH 4.19 250/264] scsi: qedi: Fix list_del corruption while removing active I/O

Greg Kroah-Hartman
2020-10-27T14:28:53Z

From: Nilesh Javali <njavali@marvell.com>

[ Upstream commit 28b35d17f9f8573d4646dd8df08917a4076a6b63 ]

While aborting the I/O, the firmware cleanup task timed out and driver
deleted the I/O from active command list. Some time later the firmware
sent the cleanup task response and driver again deleted the I/O from
active command list causing firmware to send completion for non-existent
I/O and list_del corruption of active command list.

Add fix to check if I/O is present before deleting it from the active
command list to ensure firmware sends valid I/O completion and protect
against list_del corruption.

Link: https://lore.kernel.org/r/20200908095657.26821-4-mrangankar@marvell.com
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Manish Rangankar <mrangankar@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 0d00970b7e25e..357a0acc5ed2f 100644
--- a/drivers/scsi/qedi/qedi_fw.c
+++ b/drivers/scsi/qedi/qedi_fw.c
@@ -837,8 +837,11 @@ 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);
@@ -1257,6 +1260,7 @@ 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,
@@ -1470,8 +1474,11 @@ 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);
--
2.25.1