Commit 5ada4a93 authored by Srinivasan Shanmugam's avatar Srinivasan Shanmugam Committed by Liao Chen
Browse files

drm/amd/display: Fix 'panel_cntl' could be null in 'dcn21_set_backlight_level()' 

mainline inclusion
from mainline-v6.8-rc4
commit 886571d217d7cc4e0f96f68b21238e3e25694e74
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9DNF6
CVE: CVE-2024-26661

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=886571d217d7cc4e0f96f68b21238e3e25694e74



--------------------------------

'panel_cntl' structure used to control the display panel could be null,
dereferencing it could lead to a null pointer access.

Fixes the below:
drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn21/dcn21_hwseq.c:269 dcn21_set_backlight_level() error: we previously assumed 'panel_cntl' could be null (see line 250)

Fixes: 474ac4a8 ("drm/amd/display: Implement some asic specific abm call backs.")
Cc: Yongqiang Sun <yongqiang.sun@amd.com>
Cc: Anthony Koo <Anthony.Koo@amd.com>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: default avatarSrinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: default avatarAnthony Koo <Anthony.Koo@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>

Conflicts:
	drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hwseq.c
	drivers/gpu/drm/amd/display/dc/hwss/dcn21/dcn21_hwseq.c
[lc: adjust context]
Signed-off-by: default avatarLiao Chen <liaochen4@huawei.com>
parent 08b5bb41

drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hwseq.c

+7 −1
Original line number Diff line number Diff line
@@ -205,8 +205,14 @@ bool dcn21_set_backlight_level(struct pipe_ctx *pipe_ctx, 
	union dmub_rb_cmd cmd;

	struct dc_context *dc = pipe_ctx->stream->ctx;

	struct abm *abm = pipe_ctx->stream_res.abm;

	uint32_t otg_inst = pipe_ctx->stream_res.tg->inst;

	struct timing_generator *tg = pipe_ctx->stream_res.tg;

	struct panel_cntl *panel_cntl = pipe_ctx->stream->link->panel_cntl;

	uint32_t otg_inst;



	if (!abm && !tg && !panel_cntl)

		return false;



	otg_inst = tg->inst;



	if (dc->dc->res_pool->dmcu) {

		dce110_set_backlight_level(pipe_ctx, backlight_pwm_u16_16, frame_ramp);