Read and write pointers are used to track the packet index in the memory
shared between video driver and firmware. There is a possibility of OOB
access if the read or write pointer goes beyond the queue memory size.
Add checks for the read and write pointer to avoid OOB access.

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 | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/media/platform/qcom/venus/hfi_venus.c b/drivers/media/platform/qcom/venus/hfi_venus.c
index f0b4638..dc228c4 100644
--- a/drivers/media/platform/qcom/venus/hfi_venus.c
+++ b/drivers/media/platform/qcom/venus/hfi_venus.c
@@ -206,6 +206,10 @@ static int venus_write_queue(struct venus_hfi_device *hdev,
 
 	new_wr_idx = wr_idx + dwords;
 	wr_ptr = (u32 *)(queue->qmem.kva + (wr_idx << 2));
+
+	if (wr_ptr < (u32 *)queue->qmem.kva || wr_ptr > (u32 *)(queue->qmem.kva + queue->qmem.size))
+		return -EINVAL;
+
 	if (new_wr_idx < qsize) {
 		memcpy(wr_ptr, packet, dwords << 2);
 	} else {
@@ -273,6 +277,10 @@ static int venus_read_queue(struct venus_hfi_device *hdev,
 	}
 
 	rd_ptr = (u32 *)(queue->qmem.kva + (rd_idx << 2));
+
+	if (rd_ptr < (u32 *)queue->qmem.kva || rd_ptr > (u32 *)(queue->qmem.kva + queue->qmem.size))
+		return -EINVAL;
+
 	dwords = *rd_ptr >> 2;
 	if (!dwords)
 		return -EINVAL;
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

On 27.07.2023 06:34, Vikash Garodia wrote:
> Read and write pointers are used to track the packet index in the memory
> shared between video driver and firmware. There is a possibility of OOB
> access if the read or write pointer goes beyond the queue memory size.
> Add checks for the read and write pointer to avoid OOB access.
> 
> 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 | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/media/platform/qcom/venus/hfi_venus.c b/drivers/media/platform/qcom/venus/hfi_venus.c
> index f0b4638..dc228c4 100644
> --- a/drivers/media/platform/qcom/venus/hfi_venus.c
> +++ b/drivers/media/platform/qcom/venus/hfi_venus.c
> @@ -206,6 +206,10 @@ static int venus_write_queue(struct venus_hfi_device *hdev,
>  
>  	new_wr_idx = wr_idx + dwords;
>  	wr_ptr = (u32 *)(queue->qmem.kva + (wr_idx << 2));
> +
> +	if (wr_ptr < (u32 *)queue->qmem.kva || wr_ptr > (u32 *)(queue->qmem.kva + queue->qmem.size))
Shouldn't the cases on the right side of the OR operator include a
"- 1"?

Konrad

On 7/27/2023 10:38 PM, Konrad Dybcio wrote:
> On 27.07.2023 06:34, Vikash Garodia wrote:
>> Read and write pointers are used to track the packet index in the memory
>> shared between video driver and firmware. There is a possibility of OOB
>> access if the read or write pointer goes beyond the queue memory size.
>> Add checks for the read and write pointer to avoid OOB access.
>>
>> 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 | 8 ++++++++
>>  1 file changed, 8 insertions(+)
>>
>> diff --git a/drivers/media/platform/qcom/venus/hfi_venus.c b/drivers/media/platform/qcom/venus/hfi_venus.c
>> index f0b4638..dc228c4 100644
>> --- a/drivers/media/platform/qcom/venus/hfi_venus.c
>> +++ b/drivers/media/platform/qcom/venus/hfi_venus.c
>> @@ -206,6 +206,10 @@ static int venus_write_queue(struct venus_hfi_device *hdev,
>>  
>>  	new_wr_idx = wr_idx + dwords;
>>  	wr_ptr = (u32 *)(queue->qmem.kva + (wr_idx << 2));
>> +
>> +	if (wr_ptr < (u32 *)queue->qmem.kva || wr_ptr > (u32 *)(queue->qmem.kva + queue->qmem.size))
> Shouldn't the cases on the right side of the OR operator include a
> "- 1"?

I see your point here. Possibly subtracting with sizeof(*wr_ptr) instead of "1"
would be appropriate. Similarly for read queue handling.

- Vikash

> Konrad