Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1620873

[PATCH v7 2/2] drm: Prevent release fb after cleanup drm_mode_config

Show all headers | View raw

We are freeing all framebuffers in drm_mode_config_cleanup without
sync the drm_file's fbs list.

So if someone try to unbind drm before release drm dev fd, the fbs
list would remain some invalid fb references. And that would cause
crash later in drm_fb_release.

Add a sanity check to prevent that.

Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>

---

Changes in v7:
Update commit message.

Changes in v6: None
Changes in v5: None
Changes in v2: None

 drivers/gpu/drm/drm_framebuffer.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
index e8f9c13..03c1632 100644
--- a/drivers/gpu/drm/drm_framebuffer.c
+++ b/drivers/gpu/drm/drm_framebuffer.c
@@ -583,6 +583,11 @@ void drm_fb_release(struct drm_file *priv)
 {
 	struct drm_framebuffer *fb, *tfb;
 	struct drm_mode_rmfb_work arg;
+	struct drm_minor *minor = priv->minor;
+	struct drm_device *dev = minor->dev;
+
+	if (WARN_ON(!dev->mode_config.num_fb && !list_empty(&priv->fbs)))
+		return;
 
 	INIT_LIST_HEAD(&arg.fbs);
 
-- 
2.1.4

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH v7 0/2] drm: rockchip: Fix rockchip drm unbind crash error Jeffy Chen <jeffy.chen@rock-chips.com> - 2017-04-11 05:40 +0200
  [PATCH v7 2/2] drm: Prevent release fb after cleanup drm_mode_config Jeffy Chen <jeffy.chen@rock-chips.com> - 2017-04-11 05:40 +0200
    Re: [PATCH v7 2/2] drm: Prevent release fb after cleanup  drm_mode_config Daniel Vetter <daniel@ffwll.ch> - 2017-04-12 08:40 +0200
      Re: [PATCH v7 2/2] drm: Prevent release fb after cleanup drm_mode_config jeffy <jeffy.chen@rock-chips.com> - 2017-04-12 10:50 +0200
  [PATCH v7 1/2] drm: Unplug drm device when unregistering it Jeffy Chen <jeffy.chen@rock-chips.com> - 2017-04-11 05:40 +0200
    Re: [PATCH v7 1/2] drm: Unplug drm device when unregistering it Daniel Vetter <daniel@ffwll.ch> - 2017-04-12 08:40 +0200
      Re: [PATCH v7 1/2] drm: Unplug drm device when unregistering it jeffy <jeffy.chen@rock-chips.com> - 2017-04-12 10:20 +0200
        Re: [PATCH v7 1/2] drm: Unplug drm device when unregistering it jeffy <jeffy.chen@rock-chips.com> - 2017-04-12 10:50 +0200

csiph-web