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

[ Upstream commit 06c59d97f63c1b8af521fa5aef8a716fb988b285 ]

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>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20241007235935.6216-1-jonathan@marek.ca
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
index d283d876d39ce19c7a97e4822adf698ad323de14..233975267f73c7493fc0a92853b7655fd7f8b1c5 100644 (file)
--- a/drivers/rpmsg/qcom_glink_native.c
+++ b/drivers/rpmsg/qcom_glink_native.c
@@ -1045,7 +1045,8 @@ static irqreturn_t qcom_glink_native_intr(int irq, void *data)
                        qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
                        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: