Attachment 83551 Details for Bug 67526 – Avoid the NULL deref

[patch] Avoid the NULL deref

0001-drm-i915-Do-not-dereference-NULL-crtc-or-fb-until-af.patch (text/plain), 2.38 KB, created by Chris Wilson on 2013-08-02 19:40:48 UTC

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Creator: Chris Wilson

Created: 2013-08-02 19:40:48 UTC

Size: 2.38 KB

patch

obsolete

>From 12d17f9057f1255601a566be5c0665615657921e Mon Sep 17 00:00:00 2001
>From: Chris Wilson <chris@chris-wilson.co.uk>
>Date: Fri, 2 Aug 2013 20:37:39 +0100
>Subject: [PATCH] drm/i915: Do not dereference NULL crtc or fb until after
> checking
>
>Fixes regression from
>commit 4906557eb37b7fef84fad4304acef6dedf919880
>Author: Rodrigo Vivi <rodrigo.vivi@gmail.com>
>Date:   Thu Jul 11 18:45:05 2013 -0300
>
>    drm/i915: Hook PSR functionality
>
>Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67526
>Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
>Cc: Rodrigo Vivi <rodrigo.vivi@gmail.com>
>Cc: Ben Widawsky <ben@bwidawsk.net>
>Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
>---
> drivers/gpu/drm/i915/intel_dp.c | 17 +++++++++++++----
> 1 file changed, 13 insertions(+), 4 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
>index 928b42f..7e16c6e 100644
>--- a/drivers/gpu/drm/i915/intel_dp.c
>+++ b/drivers/gpu/drm/i915/intel_dp.c
>@@ -1514,10 +1514,10 @@ static bool intel_edp_psr_match_conditions(struct intel_dp *intel_dp)
> 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> 	struct drm_device *dev = dig_port->base.base.dev;
> 	struct drm_i915_private *dev_priv = dev->dev_private;
>-	struct drm_crtc *crtc = dig_port->base.base.crtc;
>-	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
>-	struct drm_i915_gem_object *obj = to_intel_framebuffer(crtc->fb)->obj;
>-	struct intel_encoder *intel_encoder = &dp_to_dig_port(intel_dp)->base;
>+	struct drm_crtc *crtc;
>+	struct intel_crtc *intel_crtc;
>+	struct drm_i915_gem_object *obj;
>+	struct intel_encoder *intel_encoder;
> 
> 	if (!IS_HASWELL(dev)) {
> 		DRM_DEBUG_KMS("PSR not supported on this platform\n");
>@@ -1544,12 +1544,21 @@ static bool intel_edp_psr_match_conditions(struct intel_dp *intel_dp)
> 		return false;
> 	}
> 
>+	crtc = dig_port->base.base.crtc;
>+	if (crtc == NULL) {
>+		DRM_DEBUG_KMS("crtc not active for PSR\n");
>+		dev_priv->no_psr_reason = PSR_CRTC_NOT_ACTIVE;
>+		return false;
>+	}
>+
>+	intel_crtc = to_intel_crtc(crtc);
> 	if (!intel_crtc->active || !crtc->fb || !crtc->mode.clock) {
> 		DRM_DEBUG_KMS("crtc not active for PSR\n");
> 		dev_priv->no_psr_reason = PSR_CRTC_NOT_ACTIVE;
> 		return false;
> 	}
> 
>+	obj = to_intel_framebuffer(crtc->fb)->obj;
> 	if (obj->tiling_mode != I915_TILING_X ||
> 	    obj->fence_reg == I915_FENCE_REG_NONE) {
> 		DRM_DEBUG_KMS("PSR condition failed: fb not tiled or fenced\n");
>-- 
>1.8.4.rc0
>

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Attachments on bug 67526: 83281 | 83550 | 83551

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