[v2] rpmsg: glink: use only lower 16-bits of param2 for CMD_OPEN name length

[PATCH v2] rpmsg: glink: use only lower 16-bits of param2 for CMD_OPEN name length

Posted by Jonathan Marek 1 month, 2 weeks ago

The name len field of the CMD_OPEN packet is only 16-bits and the upper
16-bits of "param2" are a different "prio" field, which can be nonzero in
certain situations, and CMD_OPEN packets can be unexpectedly dropped
because of this.

Fix this by masking out the upper 16 bits of param2.

Fixes: b4f8e52b89f6 ("rpmsg: Introduce Qualcomm RPM glink driver")
Signed-off-by: Jonathan Marek <jonathan@marek.ca>
---
 drivers/rpmsg/qcom_glink_native.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
index 0b2f290069080..b534b88db3f8e 100644
--- a/drivers/rpmsg/qcom_glink_native.c
+++ b/drivers/rpmsg/qcom_glink_native.c
@@ -1204,7 +1204,8 @@ void qcom_glink_native_rx(struct qcom_glink *glink)
 			ret = qcom_glink_rx_open_ack(glink, param1);
 			break;
 		case GLINK_CMD_OPEN:
-			ret = qcom_glink_rx_defer(glink, param2);
+			/* upper 16 bits of param2 are the "prio" field */
+			ret = qcom_glink_rx_defer(glink, param2 & 0xffff);
 			break;
 		case GLINK_CMD_TX_DATA:
 		case GLINK_CMD_TX_DATA_CONT:
-- 
2.45.1

Re: [PATCH v2] rpmsg: glink: use only lower 16-bits of param2 for CMD_OPEN name length

Posted by Dmitry Baryshkov 1 month, 2 weeks ago

On Mon, Oct 07, 2024 at 07:59:35PM GMT, Jonathan Marek wrote:
> The name len field of the CMD_OPEN packet is only 16-bits and the upper
> 16-bits of "param2" are a different "prio" field, which can be nonzero in
> certain situations, and CMD_OPEN packets can be unexpectedly dropped
> because of this.
> 
> Fix this by masking out the upper 16 bits of param2.
> 
> Fixes: b4f8e52b89f6 ("rpmsg: Introduce Qualcomm RPM glink driver")
> Signed-off-by: Jonathan Marek <jonathan@marek.ca>
> ---
>  drivers/rpmsg/qcom_glink_native.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

-- 
With best wishes
Dmitry