The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 4eda776c3cefcb1f01b2d85bd8753f67606282b5 Mon Sep 17 00:00:00 2001
From: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
Date: Sat, 13 Oct 2018 12:56:54 +0200
Subject: [PATCH] drm/rockchip: psr: do not dereference encoder before it is
null checked.
'encoder' is dereferenced before it is null sanity checked, hence we
potentially have a null pointer dereference bug. Instead, initialise
drm_drv from encoder->dev->dev_private after we are sure 'encoder' is
not null.
Fixes: 5182c1a556d7f ("drm/rockchip: add an common abstracted PSR driver")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@xxxxxxxxxxxxx>
Signed-off-by: Heiko Stuebner <heiko@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20181013105654.11827-1-enric.balletbo@xxxxxxxxxxxxx
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_psr.c b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c
index 79d00d861a31..01ff3c858875 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_psr.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_psr.c
@@ -189,12 +189,14 @@ EXPORT_SYMBOL(rockchip_drm_psr_flush_all);
int rockchip_drm_psr_register(struct drm_encoder *encoder,
int (*psr_set)(struct drm_encoder *, bool enable))
{
- struct rockchip_drm_private *drm_drv = encoder->dev->dev_private;
+ struct rockchip_drm_private *drm_drv;
struct psr_drv *psr;
if (!encoder || !psr_set)
return -EINVAL;
+ drm_drv = encoder->dev->dev_private;
+
psr = kzalloc(sizeof(struct psr_drv), GFP_KERNEL);
if (!psr)
return -ENOMEM;
