diff mbox series

[3/4] media: venus: hfi: add check to handle incorrect queue size

Message ID 20241105-venus_oob-v1-3-8d4feedfe2bb@quicinc.com (mailing list archive)
State New
Headers show
Series Venus driver fixes to avoid possible OOB accesses | expand

Commit Message

Vikash Garodia Nov. 5, 2024, 8:54 a.m. UTC
qsize represents size of shared queued between driver and video
firmware. Firmware can modify this value to an invalid large value. In
such situation, empty_space will be bigger than the space actually
available. Since new_wr_idx is not checked, so the following code will
result in an OOB write.
...
qsize = qhdr->q_size

if (wr_idx >= rd_idx)
 empty_space = qsize - (wr_idx - rd_idx)
....
if (new_wr_idx < qsize) {
 memcpy(wr_ptr, packet, dwords << 2) --> OOB write

Add check to ensure qsize is within the allocated size while
reading and writing packets into the queue.

Cc: stable@vger.kernel.org
Fixes: d96d3f30c0f2 ("[media] media: venus: hfi: add Venus HFI files")
Signed-off-by: Vikash Garodia <quic_vgarodia@quicinc.com>
---
 drivers/media/platform/qcom/venus/hfi_venus.c | 6 ++++++
 1 file changed, 6 insertions(+)

Comments

Bryan O'Donoghue Nov. 5, 2024, 11:23 a.m. UTC | #1
On 05/11/2024 08:54, Vikash Garodia wrote:
> qsize represents size of shared queued between driver and video
> firmware. Firmware can modify this value to an invalid large value. In
> such situation, empty_space will be bigger than the space actually
> available. Since new_wr_idx is not checked, so the following code will
> result in an OOB write.
> ...
> qsize = qhdr->q_size
> 
> if (wr_idx >= rd_idx)
>   empty_space = qsize - (wr_idx - rd_idx)
> ....
> if (new_wr_idx < qsize) {
>   memcpy(wr_ptr, packet, dwords << 2) --> OOB write
> 
> Add check to ensure qsize is within the allocated size while
> reading and writing packets into the queue.
> 
> Cc: stable@vger.kernel.org
> Fixes: d96d3f30c0f2 ("[media] media: venus: hfi: add Venus HFI files")
> Signed-off-by: Vikash Garodia <quic_vgarodia@quicinc.com>
> ---
>   drivers/media/platform/qcom/venus/hfi_venus.c | 6 ++++++
>   1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/media/platform/qcom/venus/hfi_venus.c b/drivers/media/platform/qcom/venus/hfi_venus.c
> index f9437b6412b91c2483670a2b11f4fd43f3206404..50d92214190d88eff273a5ba3f95486f758bcc05 100644
> --- a/drivers/media/platform/qcom/venus/hfi_venus.c
> +++ b/drivers/media/platform/qcom/venus/hfi_venus.c
> @@ -187,6 +187,9 @@ static int venus_write_queue(struct venus_hfi_device *hdev,
>   	/* ensure rd/wr indices's are read from memory */
>   	rmb();
>   
> +	if (qsize > IFACEQ_QUEUE_SIZE/4)
> +		return -EINVAL;
> +
>   	if (wr_idx >= rd_idx)
>   		empty_space = qsize - (wr_idx - rd_idx);
>   	else
> @@ -255,6 +258,9 @@ static int venus_read_queue(struct venus_hfi_device *hdev,
>   	wr_idx = qhdr->write_idx;
>   	qsize = qhdr->q_size;
>   
> +	if (qsize > IFACEQ_QUEUE_SIZE/4)
> +		return -EINVAL;
> +
>   	/* make sure data is valid before using it */
>   	rmb();
>   
> 

You have this same calculation in venus_set_qhdr_defaults() really needs 
a macro or something to stop repeating the same code in another patch later.

Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
diff mbox series

Patch

diff --git a/drivers/media/platform/qcom/venus/hfi_venus.c b/drivers/media/platform/qcom/venus/hfi_venus.c
index f9437b6412b91c2483670a2b11f4fd43f3206404..50d92214190d88eff273a5ba3f95486f758bcc05 100644
--- a/drivers/media/platform/qcom/venus/hfi_venus.c
+++ b/drivers/media/platform/qcom/venus/hfi_venus.c
@@ -187,6 +187,9 @@  static int venus_write_queue(struct venus_hfi_device *hdev,
 	/* ensure rd/wr indices's are read from memory */
 	rmb();
 
+	if (qsize > IFACEQ_QUEUE_SIZE/4)
+		return -EINVAL;
+
 	if (wr_idx >= rd_idx)
 		empty_space = qsize - (wr_idx - rd_idx);
 	else
@@ -255,6 +258,9 @@  static int venus_read_queue(struct venus_hfi_device *hdev,
 	wr_idx = qhdr->write_idx;
 	qsize = qhdr->q_size;
 
+	if (qsize > IFACEQ_QUEUE_SIZE/4)
+		return -EINVAL;
+
 	/* make sure data is valid before using it */
 	rmb();