2019-11-15 09:50:27

by Colin King

[permalink] [raw]
Subject: [PATCH][next] drm/amdgpu/powerplay: fix dereference before null check of pointer hwmgr

From: Colin Ian King <[email protected]>

The assignment of adev dereferences pointer hwmgr before hwmgr is null
checked, hence there is a potential null pointer deference issue. Fix
this by assigning adev after the null check.

Addresses-Coverity: ("Dereference before null check")
Fixes: 0896d2f7ba4d ("drm/amdgpu/powerplay: properly set PP_GFXOFF_MASK")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c b/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c
index 443625c83ec9..d2909c91d65b 100644
--- a/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c
+++ b/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c
@@ -81,7 +81,7 @@ static void hwmgr_init_workload_prority(struct pp_hwmgr *hwmgr)

int hwmgr_early_init(struct pp_hwmgr *hwmgr)
{
- struct amdgpu_device *adev = hwmgr->adev;
+ struct amdgpu_device *adev;

if (!hwmgr)
return -EINVAL;
@@ -96,6 +96,8 @@ int hwmgr_early_init(struct pp_hwmgr *hwmgr)
hwmgr_init_workload_prority(hwmgr);
hwmgr->gfxoff_state_changed_by_workload = false;

+ adev = hwmgr->adev;
+
switch (hwmgr->chip_family) {
case AMDGPU_FAMILY_CI:
adev->pm.pp_feature &= ~PP_GFXOFF_MASK;
--
2.20.1


2019-11-18 06:58:46

by Evan Quan

[permalink] [raw]
Subject: RE: [PATCH][next] drm/amdgpu/powerplay: fix dereference before null check of pointer hwmgr

Reviewed-by: Evan Quan <[email protected]>

-----Original Message-----
From: Colin King <[email protected]>
Sent: Friday, November 15, 2019 5:48 PM
To: Rex Zhu <[email protected]>; Quan, Evan <[email protected]>; Deucher, Alexander <[email protected]>; Koenig, Christian <[email protected]>; Zhou, David(ChunMing) <[email protected]>; David Airlie <[email protected]>; Daniel Vetter <[email protected]>; [email protected]; [email protected]
Cc: [email protected]; [email protected]
Subject: [PATCH][next] drm/amdgpu/powerplay: fix dereference before null check of pointer hwmgr

From: Colin Ian King <[email protected]>

The assignment of adev dereferences pointer hwmgr before hwmgr is null checked, hence there is a potential null pointer deference issue. Fix this by assigning adev after the null check.

Addresses-Coverity: ("Dereference before null check")
Fixes: 0896d2f7ba4d ("drm/amdgpu/powerplay: properly set PP_GFXOFF_MASK")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c b/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c
index 443625c83ec9..d2909c91d65b 100644
--- a/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c
+++ b/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c
@@ -81,7 +81,7 @@ static void hwmgr_init_workload_prority(struct pp_hwmgr *hwmgr)

int hwmgr_early_init(struct pp_hwmgr *hwmgr) {
- struct amdgpu_device *adev = hwmgr->adev;
+ struct amdgpu_device *adev;

if (!hwmgr)
return -EINVAL;
@@ -96,6 +96,8 @@ int hwmgr_early_init(struct pp_hwmgr *hwmgr)
hwmgr_init_workload_prority(hwmgr);
hwmgr->gfxoff_state_changed_by_workload = false;

+ adev = hwmgr->adev;
+
switch (hwmgr->chip_family) {
case AMDGPU_FAMILY_CI:
adev->pm.pp_feature &= ~PP_GFXOFF_MASK;
--
2.20.1

2019-11-18 17:49:36

by Alex Deucher

[permalink] [raw]
Subject: Re: [PATCH][next] drm/amdgpu/powerplay: fix dereference before null check of pointer hwmgr

Applied. Thanks!

Alex

On Mon, Nov 18, 2019 at 1:56 AM Quan, Evan <[email protected]> wrote:
>
> Reviewed-by: Evan Quan <[email protected]>
>
> -----Original Message-----
> From: Colin King <[email protected]>
> Sent: Friday, November 15, 2019 5:48 PM
> To: Rex Zhu <[email protected]>; Quan, Evan <[email protected]>; Deucher, Alexander <[email protected]>; Koenig, Christian <[email protected]>; Zhou, David(ChunMing) <[email protected]>; David Airlie <[email protected]>; Daniel Vetter <[email protected]>; [email protected]; [email protected]
> Cc: [email protected]; [email protected]
> Subject: [PATCH][next] drm/amdgpu/powerplay: fix dereference before null check of pointer hwmgr
>
> From: Colin Ian King <[email protected]>
>
> The assignment of adev dereferences pointer hwmgr before hwmgr is null checked, hence there is a potential null pointer deference issue. Fix this by assigning adev after the null check.
>
> Addresses-Coverity: ("Dereference before null check")
> Fixes: 0896d2f7ba4d ("drm/amdgpu/powerplay: properly set PP_GFXOFF_MASK")
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c b/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c
> index 443625c83ec9..d2909c91d65b 100644
> --- a/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c
> +++ b/drivers/gpu/drm/amd/powerplay/hwmgr/hwmgr.c
> @@ -81,7 +81,7 @@ static void hwmgr_init_workload_prority(struct pp_hwmgr *hwmgr)
>
> int hwmgr_early_init(struct pp_hwmgr *hwmgr) {
> - struct amdgpu_device *adev = hwmgr->adev;
> + struct amdgpu_device *adev;
>
> if (!hwmgr)
> return -EINVAL;
> @@ -96,6 +96,8 @@ int hwmgr_early_init(struct pp_hwmgr *hwmgr)
> hwmgr_init_workload_prority(hwmgr);
> hwmgr->gfxoff_state_changed_by_workload = false;
>
> + adev = hwmgr->adev;
> +
> switch (hwmgr->chip_family) {
> case AMDGPU_FAMILY_CI:
> adev->pm.pp_feature &= ~PP_GFXOFF_MASK;
> --
> 2.20.1
>
> _______________________________________________
> dri-devel mailing list
> [email protected]
> https://lists.freedesktop.org/mailman/listinfo/dri-devel