From 39cb8280a47bfeaf493a9e8433f6e18429c0a9ba Mon Sep 17 00:00:00 2001 From: Alex Hung Date: Sat, 4 Jan 2025 17:09:56 +0800 Subject: [PATCH] drm/amd/display: Check null pointers before using dc->clk_mgr stable inclusion from stable-v5.10.227 commit 8d54001f8dccd56146973f23f3ab2ba037a21251 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAZVX4 CVE: CVE-2024-49907 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=8d54001f8dccd56146973f23f3ab2ba037a21251 -------------------------------- [ Upstream commit 95d9e0803e51d5a24276b7643b244c7477daf463 ] [WHY & HOW] dc->clk_mgr is null checked previously in the same function, indicating it might be null. Passing "dc" to "dc->hwss.apply_idle_power_optimizations", which dereferences null "dc->clk_mgr". (The function pointer resolves to "dcn35_apply_idle_power_optimizations".) This fixes 1 FORWARD_NULL issue reported by Coverity. Reviewed-by: Rodrigo Siqueira Signed-off-by: Alex Hung Signed-off-by: Tom Chung Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin Signed-off-by: Guo Mengqi --- drivers/gpu/drm/amd/display/dc/core/dc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c index 287a5b15cec9..3ecc4561a43e 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc.c @@ -3077,7 +3077,8 @@ void dc_allow_idle_optimizations(struct dc *dc, bool allow) if (allow == dc->idle_optimizations_allowed) return; - if (dc->hwss.apply_idle_power_optimizations && dc->hwss.apply_idle_power_optimizations(dc, allow)) + if (dc->hwss.apply_idle_power_optimizations && dc->clk_mgr != NULL && + dc->hwss.apply_idle_power_optimizations(dc, allow)) dc->idle_optimizations_allowed = allow; } -- Gitee