[PATCH 2/3] drm/vc4: crtc: use drm managed resources

From: Danilo Krummrich
Date: Wed Jul 13 2022 - 04:55:17 EST


Allocate the crtc objects with drmm_kzalloc() in order to tie the release
action to the underlying struct drm_device, where all the userspace
visible stuff is attached to, rather than to struct device.

This can prevent potential use-after free issues on driver unload or
EPROBE_DEFERRED backoff.

Signed-off-by: Danilo Krummrich <dakr@xxxxxxxxxx>
---
drivers/gpu/drm/vc4/vc4_crtc.c | 2 +-
drivers/gpu/drm/vc4/vc4_txp.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 9355213dc883..4b0c61cc3265 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -1273,7 +1273,7 @@ static int vc4_crtc_bind(struct device *dev, struct device *master, void *data)
struct drm_plane *destroy_plane, *temp;
int ret;

- vc4_crtc = devm_kzalloc(dev, sizeof(*vc4_crtc), GFP_KERNEL);
+ vc4_crtc = drmm_kzalloc(drm, sizeof(*vc4_crtc), GFP_KERNEL);
if (!vc4_crtc)
return -ENOMEM;
crtc = &vc4_crtc->base;
diff --git a/drivers/gpu/drm/vc4/vc4_txp.c b/drivers/gpu/drm/vc4/vc4_txp.c
index 3579d487402e..ae2193fe3b29 100644
--- a/drivers/gpu/drm/vc4/vc4_txp.c
+++ b/drivers/gpu/drm/vc4/vc4_txp.c
@@ -479,7 +479,7 @@ static int vc4_txp_bind(struct device *dev, struct device *master, void *data)
if (irq < 0)
return irq;

- txp = devm_kzalloc(dev, sizeof(*txp), GFP_KERNEL);
+ txp = drmm_kzalloc(drm, sizeof(*txp), GFP_KERNEL);
if (!txp)
return -ENOMEM;
vc4_crtc = &txp->base;
--
2.36.1