From 18d5838ad6cdac6f27a7a57e36a52bcf8678e31e Mon Sep 17 00:00:00 2001
From: Colin Ian King <colin.king@canonical.com>
Date: Mon, 16 Dec 2019 16:21:36 +0000
Subject: drm/gma500: fix null dereference of pointer fb before null check
Git-commit: 7da5492739db745d935a7044288a7307a0fb7f29
Patch-mainline: v5.6-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
Pointer fb is being dereferenced when assigning dev before it
is null checked. Fix this by only dereferencing dev after the
null check.
Fixes: 6b7ce2c4161a ("drm/gma500: Remove struct psb_fbdev")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191216162136.270114-1-colin.king@canonical.com
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/gma500/accel_2d.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/gma500/accel_2d.c b/drivers/gpu/drm/gma500/accel_2d.c
index b9e5a38632f7..adc0507545bf 100644
--- a/drivers/gpu/drm/gma500/accel_2d.c
+++ b/drivers/gpu/drm/gma500/accel_2d.c
@@ -228,8 +228,8 @@ static void psbfb_copyarea_accel(struct fb_info *info,
{
struct drm_fb_helper *fb_helper = info->par;
struct drm_framebuffer *fb = fb_helper->fb;
- struct drm_device *dev = fb->dev;
- struct drm_psb_private *dev_priv = dev->dev_private;
+ struct drm_device *dev;
+ struct drm_psb_private *dev_priv;
uint32_t offset;
uint32_t stride;
uint32_t src_format;
@@ -238,6 +238,8 @@ static void psbfb_copyarea_accel(struct fb_info *info,
if (!fb)
return;
+ dev = fb->dev;
+ dev_priv = dev->dev_private;
offset = to_gtt_range(fb->obj[0])->offset;
stride = fb->pitches[0];
--
2.28.0