[PATCH 5.8 616/633] scsi: smartpqi: Avoid crashing kernel for controller issues

Greg Kroah-Hartman
2020-10-27T16:22:37Z

From: Kevin Barnett <kevin.barnett@microsemi.com>

[ Upstream commit 9e68cccc8ef7206f0bccd590378d0dca8f9b4f57 ]

Eliminate kernel panics when getting invalid responses from controller.
Take controller offline instead of causing kernel panics.

Link: https://lore.kernel.org/r/159622929306.30579.16523318707596752828.stgit@brunhilda
Reviewed-by: Scott Teel <scott.teel@microsemi.com>
Reviewed-by: Scott Benesh <scott.benesh@microsemi.com>
Reviewed-by: Prasad Munirathnam <Prasad.Munirathnam@microsemi.com>
Reviewed-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Kevin Barnett <kevin.barnett@microsemi.com>
Signed-off-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/smartpqi/smartpqi.h | 2 +-
drivers/scsi/smartpqi/smartpqi_init.c | 101 +++++++++++++++++---------
2 files changed, 68 insertions(+), 35 deletions(-)

diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h
index 1129fe7a27edd..ee069a8b442a7 100644
--- a/drivers/scsi/smartpqi/smartpqi.h
+++ b/drivers/scsi/smartpqi/smartpqi.h
@@ -359,7 +359,7 @@ struct pqi_event_response {
struct pqi_iu_header header;
u8 event_type;
u8 reserved2 : 7;
- u8 request_acknowlege : 1;
+ u8 request_acknowledge : 1;
__le16 event_id;
__le32 additional_event_id;
union {
diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index cd157f11eb222..10afbaaa4a82f 100644
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -542,8 +542,7 @@ static int pqi_build_raid_path_request(struct pqi_ctrl_info *ctrl_info,
put_unaligned_be16(cdb_length, &cdb[7]);
break;
default:
- dev_err(&ctrl_info->pci_dev->dev, "unknown command 0x%c\n",
- cmd);
+ dev_err(&ctrl_info->pci_dev->dev, "unknown command 0x%c\n", cmd);
break;
}

@@ -2462,7 +2461,6 @@ static int pqi_raid_bypass_submit_scsi_cmd(struct pqi_ctrl_info *ctrl_info,
offload_to_mirror =
(offload_to_mirror >= layout_map_count - 1) ?
0 : offload_to_mirror + 1;
- WARN_ON(offload_to_mirror >= layout_map_count);
device->offload_to_mirror = offload_to_mirror;
/*
* Avoid direct use of device->offload_to_mirror within this
@@ -2915,10 +2913,14 @@ static int pqi_interpret_task_management_response(
return rc;
}

-static unsigned int pqi_process_io_intr(struct pqi_ctrl_info *ctrl_info,
- struct pqi_queue_group *queue_group)
+static inline void pqi_invalid_response(struct pqi_ctrl_info *ctrl_info)
+{
+ pqi_take_ctrl_offline(ctrl_info);
+}
+
+static int pqi_process_io_intr(struct pqi_ctrl_info *ctrl_info, struct pqi_queue_group *queue_group)
{
- unsigned int num_responses;
+ int num_responses;
pqi_index_t oq_pi;
pqi_index_t oq_ci;
struct pqi_io_request *io_request;
@@ -2930,6 +2932,13 @@ static unsigned int pqi_process_io_intr(struct pqi_ctrl_info *ctrl_info,

while (1) {
oq_pi = readl(queue_group->oq_pi);
+ if (oq_pi >= ctrl_info->num_elements_per_oq) {
+ pqi_invalid_response(ctrl_info);
+ dev_err(&ctrl_info->pci_dev->dev,
+ "I/O interrupt: producer index (%u) out of range (0-%u): consumer index: %u\n",
+ oq_pi, ctrl_info->num_elements_per_oq - 1, oq_ci);
+ return -1;
+ }
if (oq_pi == oq_ci)
break;

@@ -2938,10 +2947,22 @@ static unsigned int pqi_process_io_intr(struct pqi_ctrl_info *ctrl_info,
(oq_ci * PQI_OPERATIONAL_OQ_ELEMENT_LENGTH);

request_id = get_unaligned_le16(&response->request_id);
- WARN_ON(request_id >= ctrl_info->max_io_slots);
+ if (request_id >= ctrl_info->max_io_slots) {
+ pqi_invalid_response(ctrl_info);
+ dev_err(&ctrl_info->pci_dev->dev,
+ "request ID in response (%u) out of range (0-%u): producer index: %u consumer index: %u\n",
+ request_id, ctrl_info->max_io_slots - 1, oq_pi, oq_ci);
+ return -1;
+ }

io_request = &ctrl_info->io_request_pool[request_id];
- WARN_ON(atomic_read(&io_request->refcount) == 0);
+ if (atomic_read(&io_request->refcount) == 0) {
+ pqi_invalid_response(ctrl_info);
+ dev_err(&ctrl_info->pci_dev->dev,
+ "request ID in response (%u) does not match an outstanding I/O request: producer index: %u consumer index: %u\n",
+ request_id, oq_pi, oq_ci);
+ return -1;
+ }

switch (response->header.iu_type) {
case PQI_RESPONSE_IU_RAID_PATH_IO_SUCCESS:
@@ -2971,24 +2992,22 @@ static unsigned int pqi_process_io_intr(struct pqi_ctrl_info *ctrl_info,
io_request->error_info = ctrl_info->error_buffer +
(get_unaligned_le16(&response->error_index) *
PQI_ERROR_BUFFER_ELEMENT_LENGTH);
- pqi_process_io_error(response->header.iu_type,
- io_request);
+ pqi_process_io_error(response->header.iu_type, io_request);
break;
default:
+ pqi_invalid_response(ctrl_info);
dev_err(&ctrl_info->pci_dev->dev,
- "unexpected IU type: 0x%x\n",
- response->header.iu_type);
- break;
+ "unexpected IU type: 0x%x: producer index: %u consumer index: %u\n",
+ response->header.iu_type, oq_pi, oq_ci);
+ return -1;
}

- io_request->io_complete_callback(io_request,
- io_request->context);
+ io_request->io_complete_callback(io_request, io_request->context);

/*
* Note that the I/O request structure CANNOT BE TOUCHED after
* returning from the I/O completion callback!
*/
-
oq_ci = (oq_ci + 1) % ctrl_info->num_elements_per_oq;
}

@@ -3301,9 +3320,9 @@ static void pqi_ofa_capture_event_payload(struct pqi_event *event,
}
}

-static unsigned int pqi_process_event_intr(struct pqi_ctrl_info *ctrl_info)
+static int pqi_process_event_intr(struct pqi_ctrl_info *ctrl_info)
{
- unsigned int num_events;
+ int num_events;
pqi_index_t oq_pi;
pqi_index_t oq_ci;
struct pqi_event_queue *event_queue;
@@ -3317,26 +3336,31 @@ static unsigned int pqi_process_event_intr(struct pqi_ctrl_info *ctrl_info)

while (1) {
oq_pi = readl(event_queue->oq_pi);
+ if (oq_pi >= PQI_NUM_EVENT_QUEUE_ELEMENTS) {
+ pqi_invalid_response(ctrl_info);
+ dev_err(&ctrl_info->pci_dev->dev,
+ "event interrupt: producer index (%u) out of range (0-%u): consumer index: %u\n",
+ oq_pi, PQI_NUM_EVENT_QUEUE_ELEMENTS - 1, oq_ci);
+ return -1;
+ }
+
if (oq_pi == oq_ci)
break;

num_events++;
- response = event_queue->oq_element_array +
- (oq_ci * PQI_EVENT_OQ_ELEMENT_LENGTH);
+ response = event_queue->oq_element_array + (oq_ci * PQI_EVENT_OQ_ELEMENT_LENGTH);

event_index =
pqi_event_type_to_event_index(response->event_type);

- if (event_index >= 0) {
- if (response->request_acknowlege) {
- event = &ctrl_info->events[event_index];
- event->pending = true;
- event->event_type = response->event_type;
- event->event_id = response->event_id;
- event->additional_event_id =
- response->additional_event_id;
+ if (event_index >= 0 && response->request_acknowledge) {
+ event = &ctrl_info->events[event_index];
+ event->pending = true;
+ event->event_type = response->event_type;
+ event->event_id = response->event_id;
+ event->additional_event_id = response->additional_event_id;
+ if (event->event_type == PQI_EVENT_TYPE_OFA)
pqi_ofa_capture_event_payload(event, response);
- }
}

oq_ci = (oq_ci + 1) % PQI_NUM_EVENT_QUEUE_ELEMENTS;
@@ -3451,7 +3475,8 @@ static irqreturn_t pqi_irq_handler(int irq, void *data)
{
struct pqi_ctrl_info *ctrl_info;
struct pqi_queue_group *queue_group;
- unsigned int num_responses_handled;
+ int num_io_responses_handled;
+ int num_events_handled;

queue_group = data;
ctrl_info = queue_group->ctrl_info;
@@ -3459,17 +3484,25 @@ static irqreturn_t pqi_irq_handler(int irq, void *data)
if (!pqi_is_valid_irq(ctrl_info))
return IRQ_NONE;

- num_responses_handled = pqi_process_io_intr(ctrl_info, queue_group);
+ num_io_responses_handled = pqi_process_io_intr(ctrl_info, queue_group);
+ if (num_io_responses_handled < 0)
+ goto out;

- if (irq == ctrl_info->event_irq)
- num_responses_handled += pqi_process_event_intr(ctrl_info);
+ if (irq == ctrl_info->event_irq) {
+ num_events_handled = pqi_process_event_intr(ctrl_info);
+ if (num_events_handled < 0)
+ goto out;
+ } else {
+ num_events_handled = 0;
+ }

- if (num_responses_handled)
+ if (num_io_responses_handled + num_events_handled > 0)
atomic_inc(&ctrl_info->num_interrupts);

pqi_start_io(ctrl_info, queue_group, RAID_PATH, NULL);
pqi_start_io(ctrl_info, queue_group, AIO_PATH, NULL);

+out:
return IRQ_HANDLED;
}

--
2.25.1