[PATCH] habanalabs: prevent possible out-of-bounds array access

From: Oded Gabbay
Date: Sun Jul 12 2020 - 16:46:24 EST


Queue index is received from the user. Therefore, we must validate it
before using it to access the queue props array.

Signed-off-by: Oded Gabbay <oded.gabbay@xxxxxxxxx>
---
drivers/misc/habanalabs/command_submission.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/misc/habanalabs/command_submission.c b/drivers/misc/habanalabs/command_submission.c
index b0f62cbbdc87..f3a8f113865d 100644
--- a/drivers/misc/habanalabs/command_submission.c
+++ b/drivers/misc/habanalabs/command_submission.c
@@ -499,11 +499,19 @@ static int validate_queue_index(struct hl_device *hdev,
struct asic_fixed_properties *asic = &hdev->asic_prop;
struct hw_queue_properties *hw_queue_prop;

+ /* This must be checked here to prevent out-of-bounds access to
+ * hw_queues_props array
+ */
+ if (chunk->queue_index >= HL_MAX_QUEUES) {
+ dev_err(hdev->dev, "Queue index %d is invalid\n",
+ chunk->queue_index);
+ return -EINVAL;
+ }
+
hw_queue_prop = &asic->hw_queues_props[chunk->queue_index];

- if ((chunk->queue_index >= HL_MAX_QUEUES) ||
- (hw_queue_prop->type == QUEUE_TYPE_NA)) {
- dev_err(hdev->dev, "Queue index %d is invalid\n",
+ if (hw_queue_prop->type == QUEUE_TYPE_NA) {
+ dev_err(hdev->dev, "Queue index %d is not applicable\n",
chunk->queue_index);
return -EINVAL;
}
--
2.17.1