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: 950a7388f02b ("rpmsg: Turn name service into a stand alone driver")
Fixes: c0cdc19f84a4 ("rpmsg: Driver for user space endpoint interface")
Cc: <[email protected]>
Signed-off-by: Krzysztof Kozlowski <[email protected]>
---
drivers/rpmsg/rpmsg_core.c | 3 ++-
drivers/rpmsg/rpmsg_internal.h | 13 +++++++++++--
drivers/rpmsg/rpmsg_ns.c | 14 ++++++++++++--
include/linux/rpmsg.h | 6 ++++--
4 files changed, 29 insertions(+), 7 deletions(-)
diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
index d9e612f4f0f2..6e2bf2742973 100644
--- a/drivers/rpmsg/rpmsg_core.c
+++ b/drivers/rpmsg/rpmsg_core.c
@@ -397,7 +397,8 @@ field##_store(struct device *dev, struct device_attribute *attr, \
const char *buf, size_t sz) \
{ \
struct rpmsg_device *rpdev = to_rpmsg_device(dev); \
- char *new, *old; \
+ const char *old; \
+ char *new; \
\
new = kstrndup(buf, sz, GFP_KERNEL); \
if (!new) \
diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
index b1245d3ed7c6..31345d6e9a7e 100644
--- a/drivers/rpmsg/rpmsg_internal.h
+++ b/drivers/rpmsg/rpmsg_internal.h
@@ -92,10 +92,19 @@ int rpmsg_release_channel(struct rpmsg_device *rpdev,
*/
static inline int rpmsg_chrdev_register_device(struct rpmsg_device *rpdev)
{
+ int ret;
+
strcpy(rpdev->id.name, "rpmsg_chrdev");
- rpdev->driver_override = "rpmsg_chrdev";
+ ret = driver_set_override(&rpdev->dev, &rpdev->driver_override,
+ "rpmsg_chrdev", strlen("rpmsg_chrdev"));
+ if (ret)
+ return ret;
+
+ ret = rpmsg_register_device(rpdev);
+ if (ret)
+ kfree(rpdev->driver_override);
- return rpmsg_register_device(rpdev);
+ return ret;
}
#endif
diff --git a/drivers/rpmsg/rpmsg_ns.c b/drivers/rpmsg/rpmsg_ns.c
index 762ff1ae279f..95a51543f5ad 100644
--- a/drivers/rpmsg/rpmsg_ns.c
+++ b/drivers/rpmsg/rpmsg_ns.c
@@ -20,12 +20,22 @@
*/
int rpmsg_ns_register_device(struct rpmsg_device *rpdev)
{
+ int ret;
+
strcpy(rpdev->id.name, "rpmsg_ns");
- rpdev->driver_override = "rpmsg_ns";
+ ret = driver_set_override(&rpdev->dev, &rpdev->driver_override,
+ "rpmsg_ns", strlen("rpmsg_ns"));
+ if (ret)
+ return ret;
+
rpdev->src = RPMSG_NS_ADDR;
rpdev->dst = RPMSG_NS_ADDR;
- return rpmsg_register_device(rpdev);
+ ret = rpmsg_register_device(rpdev);
+ if (ret)
+ kfree(rpdev->driver_override);
+
+ return ret;
}
EXPORT_SYMBOL(rpmsg_ns_register_device);
diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
index 02fa9116cd60..20c8cd1cde21 100644
--- a/include/linux/rpmsg.h
+++ b/include/linux/rpmsg.h
@@ -41,7 +41,9 @@ struct rpmsg_channel_info {
* rpmsg_device - device that belong to the rpmsg bus
* @dev: the device struct
* @id: device id (used to match between rpmsg drivers and devices)
- * @driver_override: driver name to force a match
+ * @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.
* @src: local address
* @dst: destination address
* @ept: the rpmsg endpoint of this channel
@@ -51,7 +53,7 @@ struct rpmsg_channel_info {
struct rpmsg_device {
struct device dev;
struct rpmsg_device_id id;
- char *driver_override;
+ const char *driver_override;
u32 src;
u32 dst;
struct rpmsg_endpoint *ept;
--
2.32.0
On Sun 27 Feb 07:53 CST 2022, 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: 950a7388f02b ("rpmsg: Turn name service into a stand alone driver")
> Fixes: c0cdc19f84a4 ("rpmsg: Driver for user space endpoint interface")
> Cc: <[email protected]>
> Signed-off-by: Krzysztof Kozlowski <[email protected]>
Reviewed-by: Bjorn Andersson <[email protected]>
Regards,
Bjorn
> ---
> drivers/rpmsg/rpmsg_core.c | 3 ++-
> drivers/rpmsg/rpmsg_internal.h | 13 +++++++++++--
> drivers/rpmsg/rpmsg_ns.c | 14 ++++++++++++--
> include/linux/rpmsg.h | 6 ++++--
> 4 files changed, 29 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
> index d9e612f4f0f2..6e2bf2742973 100644
> --- a/drivers/rpmsg/rpmsg_core.c
> +++ b/drivers/rpmsg/rpmsg_core.c
> @@ -397,7 +397,8 @@ field##_store(struct device *dev, struct device_attribute *attr, \
> const char *buf, size_t sz) \
> { \
> struct rpmsg_device *rpdev = to_rpmsg_device(dev); \
> - char *new, *old; \
> + const char *old; \
> + char *new; \
> \
> new = kstrndup(buf, sz, GFP_KERNEL); \
> if (!new) \
> diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
> index b1245d3ed7c6..31345d6e9a7e 100644
> --- a/drivers/rpmsg/rpmsg_internal.h
> +++ b/drivers/rpmsg/rpmsg_internal.h
> @@ -92,10 +92,19 @@ int rpmsg_release_channel(struct rpmsg_device *rpdev,
> */
> static inline int rpmsg_chrdev_register_device(struct rpmsg_device *rpdev)
> {
> + int ret;
> +
> strcpy(rpdev->id.name, "rpmsg_chrdev");
> - rpdev->driver_override = "rpmsg_chrdev";
> + ret = driver_set_override(&rpdev->dev, &rpdev->driver_override,
> + "rpmsg_chrdev", strlen("rpmsg_chrdev"));
> + if (ret)
> + return ret;
> +
> + ret = rpmsg_register_device(rpdev);
> + if (ret)
> + kfree(rpdev->driver_override);
>
> - return rpmsg_register_device(rpdev);
> + return ret;
> }
>
> #endif
> diff --git a/drivers/rpmsg/rpmsg_ns.c b/drivers/rpmsg/rpmsg_ns.c
> index 762ff1ae279f..95a51543f5ad 100644
> --- a/drivers/rpmsg/rpmsg_ns.c
> +++ b/drivers/rpmsg/rpmsg_ns.c
> @@ -20,12 +20,22 @@
> */
> int rpmsg_ns_register_device(struct rpmsg_device *rpdev)
> {
> + int ret;
> +
> strcpy(rpdev->id.name, "rpmsg_ns");
> - rpdev->driver_override = "rpmsg_ns";
> + ret = driver_set_override(&rpdev->dev, &rpdev->driver_override,
> + "rpmsg_ns", strlen("rpmsg_ns"));
> + if (ret)
> + return ret;
> +
> rpdev->src = RPMSG_NS_ADDR;
> rpdev->dst = RPMSG_NS_ADDR;
>
> - return rpmsg_register_device(rpdev);
> + ret = rpmsg_register_device(rpdev);
> + if (ret)
> + kfree(rpdev->driver_override);
> +
> + return ret;
> }
> EXPORT_SYMBOL(rpmsg_ns_register_device);
>
> diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
> index 02fa9116cd60..20c8cd1cde21 100644
> --- a/include/linux/rpmsg.h
> +++ b/include/linux/rpmsg.h
> @@ -41,7 +41,9 @@ struct rpmsg_channel_info {
> * rpmsg_device - device that belong to the rpmsg bus
> * @dev: the device struct
> * @id: device id (used to match between rpmsg drivers and devices)
> - * @driver_override: driver name to force a match
> + * @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.
> * @src: local address
> * @dst: destination address
> * @ept: the rpmsg endpoint of this channel
> @@ -51,7 +53,7 @@ struct rpmsg_channel_info {
> struct rpmsg_device {
> struct device dev;
> struct rpmsg_device_id id;
> - char *driver_override;
> + const char *driver_override;
> u32 src;
> u32 dst;
> struct rpmsg_endpoint *ept;
> --
> 2.32.0
>