linux-kernel - Re: [PATCH] drm/amd/display: Fix null check for pipe_ctx->plane_state in resource_build_scaling

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <14852987-a774-4952-a166-b84880566564@amd.com>
Date: Tue, 25 Feb 2025 15:53:38 -0700
From: Alex Hung <alex.hung@....com>
To: Ma Ke <make24@...as.ac.cn>, harry.wentland@....com, sunpeng.li@....com,
 Rodrigo.Siqueira@....com, alexander.deucher@....com,
 christian.koenig@....com, Xinhui.Pan@....com, airlied@...il.com,
 simona@...ll.ch, wenjing.liu@....com, dillon.varone@....com,
 Samson.Tam@....com, yi-lchen@....com, chris.park@....com,
 aurabindo.pillai@....com, george.shen@....com, gabe.teeger@....com,
 Yihan.Zhu@....com, Tony.Cheng@....com
Cc: amd-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
 linux-kernel@...r.kernel.org, stable@...r.kernel.org
Subject: Re: [PATCH] drm/amd/display: Fix null check for pipe_ctx->plane_state
 in resource_build_scaling_params



On 2/23/25 23:32, Ma Ke wrote:
> Null pointer dereference issue could occur when pipe_ctx->plane_state
> is null. The fix adds a check to ensure 'pipe_ctx->plane_state' is not
> null before accessing. This prevents a null pointer dereference.
> 
> Found by code review.
> 
> Cc: stable@...r.kernel.org
> Fixes: 3be5262e353b ("drm/amd/display: Rename more dc_surface stuff to plane_state")
> Signed-off-by: Ma Ke <make24@...as.ac.cn>
> ---
>   drivers/gpu/drm/amd/display/dc/core/dc_resource.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
> index 520a34a42827..88e8ae63a07f 100644
> --- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
> +++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
> @@ -1452,6 +1452,9 @@ bool resource_build_scaling_params(struct pipe_ctx *pipe_ctx)
>   	struct scaling_taps temp = {0};
>   	bool res = false;
>   
> +	if (!plane_state)
> +		return false;
> +

This if statement can be merged with the following one such as below, 
and it also allows ASSERT to kick in instead of failing silently.


         DC_LOGGER_INIT(pipe_ctx->stream->ctx->logger);

         /* Invalid input */
-       if (!plane_state->dst_rect.width ||
-                       !plane_state->dst_rect.height ||
-                       !plane_state->src_rect.width ||
-                       !plane_state->src_rect.height) {
+       if (!plane_state ||
+           !plane_state->dst_rect.width ||
+           !plane_state->dst_rect.height ||
+           !plane_state->src_rect.width ||
+           !plane_state->src_rect.height) {
                 ASSERT(0);


>   	DC_LOGGER_INIT(pipe_ctx->stream->ctx->logger);
>   
>   	/* Invalid input */