4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jonathan Marek <jonathan@xxxxxxxx>
[ 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@xxxxxxxx>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20241007235935.6216-1-jonathan@xxxxxxxx
Signed-off-by: Bjorn Andersson <andersson@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 d283d876d39ce..233975267f73c 100644
--- 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:
--
2.43.0
