Hi Laurent,
Le lun. 18 janv. 2021 à 11:43, Laurent Pinchart
<laurent.pinchart@xxxxxxxxxxxxxxxx> a écrit :
Hi Paul,
Thank you for the patch.
On Sun, Jan 17, 2021 at 11:26:45AM +0000, Paul Cercueil wrote:
Since the encoders have been devm-allocated, they will be freed way
before drm_mode_config_cleanup() is called. To avoid use-after-free
conditions, we then must ensure that drm_encoder_cleanup() is called
before the encoders are freed.
How about allocating the encoder with drmm_encoder_alloc() instead ?
That would work, but it is not yet in drm-misc-fixes :(
-Paul
Fixes: c369cb27c267 ("drm/ingenic: Support multiple panels/bridges")
Cc: <stable@xxxxxxxxxxxxxxx> # 5.8+
Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
index 368bfef8b340..d23a3292a0e0 100644
--- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
+++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
@@ -803,6 +803,11 @@ static void __maybe_unused
ingenic_drm_release_rmem(void *d)
of_reserved_mem_device_release(d);
}
+static void ingenic_drm_encoder_cleanup(void *encoder)
+{
+ drm_encoder_cleanup(encoder);
+}
+
static int ingenic_drm_bind(struct device *dev, bool
has_components)
{
struct platform_device *pdev = to_platform_device(dev);
@@ -1011,6 +1016,11 @@ static int ingenic_drm_bind(struct device
*dev, bool has_components)
return ret;
}
+ ret = devm_add_action_or_reset(dev, ingenic_drm_encoder_cleanup,
+ encoder);
+ if (ret)
+ return ret;
+
ret = drm_bridge_attach(encoder, bridge, NULL, 0);
if (ret) {
dev_err(dev, "Unable to attach bridge\n");
--
Regards,
Laurent Pinchart
