v4l2_async_notifier_add_subdev() requires the asd to be allocated
dynamically, but the max9286 driver embeds it in the max9286_source
structure. This causes memory corruption when the notifier is destroyed
at remove time with v4l2_async_notifier_cleanup().
Fix this issue by registering the asd with
v4l2_async_notifier_add_fwnode_subdev(), which allocates it dynamically
internally. A new max9286_asd structure is introduced, to store a
pointer to the corresonding max9286_source that needs to be accessed
from bound and unbind callbacks. There's no need to take an extra
explicit reference to the fwnode anymore as
v4l2_async_notifier_add_fwnode_subdev() does so internally.
While at it, use %u instead of %d to print the unsigned index in the
error message from the v4l2_async_notifier_add_fwnode_subdev() error
path.
Fixes: 66d8c9d2422d ("media: i2c: Add MAX9286 driver")
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
---
drivers/media/i2c/max9286.c | 38 +++++++++++++++++++------------------
1 file changed, 20 insertions(+), 18 deletions(-)
diff --git a/drivers/media/i2c/max9286.c b/drivers/media/i2c/max9286.c
index 47f280518fdb..5d890dddb376 100644
--- a/drivers/media/i2c/max9286.c
+++ b/drivers/media/i2c/max9286.c
@@ -135,13 +135,19 @@
#define MAX9286_SRC_PAD 4
struct max9286_source {
- struct v4l2_async_subdev asd;
struct v4l2_subdev *sd;
struct fwnode_handle *fwnode;
};
-#define asd_to_max9286_source(_asd) \
- container_of(_asd, struct max9286_source, asd)
+struct max9286_asd {
+ struct v4l2_async_subdev base;
+ struct max9286_source *source;
+};
+
+static inline struct max9286_asd *to_max9286_asd(struct v4l2_async_subdev *asd)
+{
+ return container_of(asd, struct max9286_asd, base);
+}
struct max9286_priv {
struct i2c_client *client;
@@ -480,7 +486,7 @@ static int max9286_notify_bound(struct v4l2_async_notifier *notifier,
struct v4l2_async_subdev *asd)
{
struct max9286_priv *priv = sd_to_max9286(notifier->sd);
- struct max9286_source *source = asd_to_max9286_source(asd);
+ struct max9286_source *source = to_max9286_asd(asd)->source;
unsigned int index = to_index(priv, source);
unsigned int src_pad;
int ret;
@@ -544,7 +550,7 @@ static void max9286_notify_unbind(struct v4l2_async_notifier *notifier,
struct v4l2_async_subdev *asd)
{
struct max9286_priv *priv = sd_to_max9286(notifier->sd);
- struct max9286_source *source = asd_to_max9286_source(asd);
+ struct max9286_source *source = to_max9286_asd(asd)->source;
unsigned int index = to_index(priv, source);
source->sd = NULL;
@@ -569,23 +575,19 @@ static int max9286_v4l2_notifier_register(struct max9286_priv *priv)
for_each_source(priv, source) {
unsigned int i = to_index(priv, source);
+ struct v4l2_async_subdev *asd;
- source->asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
- source->asd.match.fwnode = source->fwnode;
-
- ret = v4l2_async_notifier_add_subdev(&priv->notifier,
- &source->asd);
- if (ret) {
- dev_err(dev, "Failed to add subdev for source %d", i);
+ asd = v4l2_async_notifier_add_fwnode_subdev(&priv->notifier,
+ source->fwnode,
+ sizeof(*asd));
+ if (IS_ERR(asd)) {
+ dev_err(dev, "Failed to add subdev for source %u: %ld",
+ i, PTR_ERR(asd));
v4l2_async_notifier_cleanup(&priv->notifier);
- return ret;
+ return PTR_ERR(asd);
}
- /*
- * Balance the reference counting handled through
- * v4l2_async_notifier_cleanup()
- */
- fwnode_handle_get(source->fwnode);
+ to_max9286_asd(asd)->source = source;
}
priv->notifier.ops = &max9286_notify_ops;
--
Regards,
Laurent Pinchart
