Emil Velikov
2011-Aug-21 21:48 UTC
[Nouveau] [PATCH] drm/nv50/crtc: Bail out if FB is not bound to crtc
Fixes possbile NULL pointer dereference
Resolves 'kernel crash in nv50_crtc_do_mode_set_base during shutdown'
https://bugs.freedesktop.org/show_bug.cgi?id=40005
Signed-off-by: Emil Velikov <emil.l.velikov at gmail.com>
---
drivers/gpu/drm/nouveau/nv50_crtc.c | 12 ++++++++++--
1 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nv50_crtc.c
b/drivers/gpu/drm/nouveau/nv50_crtc.c
index 636e3fb..882080e 100644
--- a/drivers/gpu/drm/nouveau/nv50_crtc.c
+++ b/drivers/gpu/drm/nouveau/nv50_crtc.c
@@ -517,12 +517,18 @@ nv50_crtc_do_mode_set_base(struct drm_crtc *crtc,
struct drm_device *dev = nv_crtc->base.dev;
struct drm_nouveau_private *dev_priv = dev->dev_private;
struct nouveau_channel *evo = nv50_display(dev)->master;
- struct drm_framebuffer *drm_fb = nv_crtc->base.fb;
- struct nouveau_framebuffer *fb = nouveau_framebuffer(drm_fb);
+ struct drm_framebuffer *drm_fb;
+ struct nouveau_framebuffer *fb;
int ret;
NV_DEBUG_KMS(dev, "index %d\n", nv_crtc->index);
+ /* no fb bound */
+ if (!atomic && !crtc->fb) {
+ NV_DEBUG_KMS(dev, "No FB bound\n");
+ return 0;
+ }
+
/* If atomic, we want to switch to the fb we were passed, so
* now we update pointers to do that. (We don't pin; just
* assume we're already pinned and update the base address.)
@@ -531,6 +537,8 @@ nv50_crtc_do_mode_set_base(struct drm_crtc *crtc,
drm_fb = passed_fb;
fb = nouveau_framebuffer(passed_fb);
} else {
+ drm_fb = crtc->fb;
+ fb = nouveau_framebuffer(crtc->fb);
/* If not atomic, we can go ahead and pin, and unpin the
* old fb we were passed.
*/
--
1.7.6