Re: [PATCH v3 10/11] slimbus: qcom-ngd: Fix kfree() of static memory on setting driver_override

From: Srinivas Kandagatla
Date: Tue Mar 01 2022 - 12:28:32 EST




On 27/02/2022 13:53, Krzysztof Kozlowski wrote:
The driver_override field from platform driver should not be initialized
from static memory (string literal) because the core later kfree() it,
for example when driver_override is set via sysfs.

Use dedicated helper to set driver_override properly.

Fixes: 917809e2280b ("slimbus: ngd: Add qcom SLIMBus NGD driver")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>

LGTM,

Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>

---
drivers/slimbus/qcom-ngd-ctrl.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/slimbus/qcom-ngd-ctrl.c b/drivers/slimbus/qcom-ngd-ctrl.c
index 7040293c2ee8..e5d9fdb81eb0 100644
--- a/drivers/slimbus/qcom-ngd-ctrl.c
+++ b/drivers/slimbus/qcom-ngd-ctrl.c
@@ -1434,6 +1434,7 @@ static int of_qcom_slim_ngd_register(struct device *parent,
const struct of_device_id *match;
struct device_node *node;
u32 id;
+ int ret;
match = of_match_node(qcom_slim_ngd_dt_match, parent->of_node);
data = match->data;
@@ -1455,7 +1456,17 @@ static int of_qcom_slim_ngd_register(struct device *parent,
}
ngd->id = id;
ngd->pdev->dev.parent = parent;
- ngd->pdev->driver_override = QCOM_SLIM_NGD_DRV_NAME;
+
+ ret = driver_set_override(&ngd->pdev->dev,
+ &ngd->pdev->driver_override,
+ QCOM_SLIM_NGD_DRV_NAME,
+ strlen(QCOM_SLIM_NGD_DRV_NAME));
+ if (ret) {
+ platform_device_put(ngd->pdev);
+ kfree(ngd);
+ of_node_put(node);
+ return ret;
+ }
ngd->pdev->dev.of_node = node;
ctrl->ngd = ngd;