Re: [PATCH] rpmsg: glink: Release driver_override

From: Chris Lew
Date: Tue Jan 17 2023 - 20:08:23 EST




On 1/9/2023 2:38 PM, Bjorn Andersson wrote:
Upon termination of the rpmsg_device, driver_override needs to be freed
to avoid leaking the potentially assigned string.

Fixes: 42cd402b8fd4 ("rpmsg: Fix kfree() of static memory on setting driver_override")
Fixes: 39e47767ec9b ("rpmsg: Add driver_override device attribute for rpmsg_device")
Signed-off-by: Bjorn Andersson <quic_bjorande@xxxxxxxxxxx>
---
drivers/rpmsg/qcom_glink_native.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
index 8620eea1dc8a..046271e439c5 100644
--- a/drivers/rpmsg/qcom_glink_native.c
+++ b/drivers/rpmsg/qcom_glink_native.c
@@ -1454,6 +1454,7 @@ static void qcom_glink_rpdev_release(struct device *dev)
{
struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+ kfree(rpdev->driver_override);

I see in Krzysztof's original patch to fix up the driver_override we do kfree in other areas of rpmsg.

More of a just curious as to why don't we use the driver_set_override function to clear the string? It's mentioned in the rpmsg header that the helper should be used.

--- include/linux/rpmsg.h
* @driver_override: driver name to force a match; do not set directly,
* because core frees it; use driver_set_override() to
* set or clear it.

kfree(rpdev);
}
@@ -1697,6 +1698,7 @@ static void qcom_glink_device_release(struct device *dev)
/* Release qcom_glink_alloc_channel() reference */
kref_put(&channel->refcount, qcom_glink_channel_release);
+ kfree(rpdev->driver_override);
kfree(rpdev);
}