linux-kernel - Re: [PATCH][next] drm/amdgpu/powerplay: fix dereference before null check of pointer hwmgr

Open Source and information security mailing list archives

Message-ID: <CADnq5_ODJOk3vV1QBQRQkMxZTa5reBqsPy-Q+1rrEBw4dJEtoQ@mail.gmail.com>
Date:   Mon, 18 Nov 2019 12:47:49 -0500
From:   Alex Deucher <alexdeucher@...il.com>
To:     "Quan, Evan" <Evan.Quan@....com>
Cc:     Colin King <colin.king@...onical.com>, Rex Zhu <rex.zhu@....com>,
        "Deucher, Alexander" <Alexander.Deucher@....com>,
        "Koenig, Christian" <Christian.Koenig@....com>,
        "Zhou, David(ChunMing)" <David1.Zhou@....com>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>,
        "amd-gfx@...ts.freedesktop.org" <amd-gfx@...ts.freedesktop.org>,
        "dri-devel@...ts.freedesktop.org" <dri-devel@...ts.freedesktop.org>,
        "kernel-janitors@...r.kernel.org" <kernel-janitors@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
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 <Evan.Quan@....com> wrote:
>
> Reviewed-by: Evan Quan <evan.quan@....com>
>
> -----Original Message-----
> From: Colin King <colin.king@...onical.com>
> Sent: Friday, November 15, 2019 5:48 PM
> To: Rex Zhu <rex.zhu@....com>; Quan, Evan <Evan.Quan@....com>; Deucher, Alexander <Alexander.Deucher@....com>; Koenig, Christian <Christian.Koenig@....com>; Zhou, David(ChunMing) <David1.Zhou@....com>; David Airlie <airlied@...ux.ie>; Daniel Vetter <daniel@...ll.ch>; amd-gfx@...ts.freedesktop.org; dri-devel@...ts.freedesktop.org
> Cc: kernel-janitors@...r.kernel.org; linux-kernel@...r.kernel.org
> Subject: [PATCH][next] drm/amdgpu/powerplay: fix dereference before null check of pointer hwmgr
>
> From: Colin Ian King <colin.king@...onical.com>
>
> 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 <colin.king@...onical.com>
> ---
>  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
> dri-devel@...ts.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives