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* [PATCH 1/2] drm/msm: fix potential NULL dereference in cleanup
@ 2021-10-13  8:11 Dan Carpenter
  2021-10-13  8:13 ` [PATCH 2/2] drm/msm: uninitialized variable in msm_gem_import() Dan Carpenter
  0 siblings, 1 reply; 2+ messages in thread
From: Dan Carpenter @ 2021-10-13  8:11 UTC (permalink / raw)
  To: Rob Clark
  Cc: Sean Paul, David Airlie, Daniel Vetter, linux-arm-msm, dri-devel,
	freedreno, kernel-janitors

The "msm_obj->node" list needs to be initialized earlier so that the
list_del() in msm_gem_free_object() doesn't experience a NULL pointer
dereference.

Fixes: 6ed0897cd800 ("drm/msm: Fix debugfs deadlock")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
 drivers/gpu/drm/msm/msm_gem.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 40a9863f5951..49185d524be3 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -1132,6 +1132,7 @@ static int msm_gem_new_impl(struct drm_device *dev,
 	msm_obj->flags = flags;
 	msm_obj->madv = MSM_MADV_WILLNEED;
 
+	INIT_LIST_HEAD(&msm_obj->node);
 	INIT_LIST_HEAD(&msm_obj->vmas);
 
 	*obj = &msm_obj->base;
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* [PATCH 2/2] drm/msm: uninitialized variable in msm_gem_import()
  2021-10-13  8:11 [PATCH 1/2] drm/msm: fix potential NULL dereference in cleanup Dan Carpenter
@ 2021-10-13  8:13 ` Dan Carpenter
  0 siblings, 0 replies; 2+ messages in thread
From: Dan Carpenter @ 2021-10-13  8:13 UTC (permalink / raw)
  To: Rob Clark
  Cc: Sean Paul, David Airlie, Daniel Vetter, David Brown,
	linux-arm-msm, dri-devel, freedreno, kernel-janitors

The msm_gem_new_impl() function cleans up after itself so there is no
need to call drm_gem_object_put().  Conceptually, it does not make sense
to call a kref_put() function until after the reference counting has
been initialized which happens immediately after this call in the
drm_gem_(private_)object_init() functions.

In the msm_gem_import() function the "obj" pointer is uninitialized, so
it will lead to a crash.

Fixes: 05b849111c07 ("drm/msm: prime support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
 drivers/gpu/drm/msm/msm_gem.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 49185d524be3..0e491cd21c53 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -1167,7 +1167,7 @@ struct drm_gem_object *msm_gem_new(struct drm_device *dev, uint32_t size, uint32
 
 	ret = msm_gem_new_impl(dev, size, flags, &obj);
 	if (ret)
-		goto fail;
+		return ERR_PTR(ret);
 
 	msm_obj = to_msm_bo(obj);
 
@@ -1251,7 +1251,7 @@ struct drm_gem_object *msm_gem_import(struct drm_device *dev,
 
 	ret = msm_gem_new_impl(dev, size, MSM_BO_WC, &obj);
 	if (ret)
-		goto fail;
+		return ERR_PTR(ret);
 
 	drm_gem_private_object_init(dev, obj, size);
 
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 2+ messages in thread

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2021-10-13  8:11 [PATCH 1/2] drm/msm: fix potential NULL dereference in cleanup Dan Carpenter
2021-10-13  8:13 ` [PATCH 2/2] drm/msm: uninitialized variable in msm_gem_import() Dan Carpenter

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