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| author |   Charles Keepax <ckeepax@opensource.wolfsonmicro.com> | 2015-02-17 17:14:41 +0000 |
|---|---|---|
| committer |   Inki Dae <inki.dae@samsung.com> | 2015-03-18 20:41:18 +0900 |
| commit | 995fdfb9c8e9cf9707966c6936eb6ea1a8b68194 (patch) | |
| tree | 4ac3d9d7239baeb20098f86dea85154e106207c8 /drivers/gpu | |
| parent | drm/exynos: IS_ERR() vs NULL bug (diff) | |
| download | linux-dev-995fdfb9c8e9cf9707966c6936eb6ea1a8b68194.tar.xz linux-dev-995fdfb9c8e9cf9707966c6936eb6ea1a8b68194.zip | |
drm/exynos: Check for NULL dereference of crtc
The commit "drm/exynos: remove exynos_plane_dpms" (d9ea6256) removed the
use of the enabled flag, which means that the code may attempt to call
win_enable on a NULL crtc. This results in the following oops on
Arndale:
[ 1.673479] Unable to handle kernel NULL pointer dereference at virtual address 00000368
[ 1.681500] pgd = c0004000
[ 1.684154] [00000368] *pgd=00000000
[ 1.687713] Internal error: Oops: 5 [#1] PREEMPT SMP ARM
[ 1.693012] Modules linked in:
[ 1.696045] CPU: 1 PID: 1 Comm: swapper/0 Not tainted
3.19.0-07545-g57485fa #1907
[ 1.703524] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
(....)
[ 2.014803] [<c02f9cfc>] (exynos_plane_destroy) from [<c02e61b4>] (drm_mode_config_cleanup+0x168/0x20c)
[ 2.024178] [<c02e61b4>] (drm_mode_config_cleanup) from [<c02f66fc>] (exynos_drm_load+0xac/0x12c)
This patch adds in a check to ensure exynos_crtc is not NULL before it
is dereferenced.
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/exynos/exynos_drm_plane.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/gpu/drm/exynos/exynos_drm_plane.c b/drivers/gpu/drm/exynos/exynos_drm_plane.c index a5616872eee7..8ad5b7294eb4 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_plane.c +++ b/drivers/gpu/drm/exynos/exynos_drm_plane.c @@ -175,7 +175,7 @@ static int exynos_disable_plane(struct drm_plane *plane) struct exynos_drm_plane *exynos_plane = to_exynos_plane(plane); struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(plane->crtc); - if (exynos_crtc->ops->win_disable) + if (exynos_crtc && exynos_crtc->ops->win_disable) exynos_crtc->ops->win_disable(exynos_crtc, exynos_plane->zpos); |