From: Zichen Xie Date: Tue, 29 Oct 2024 19:42:10 +0000 (-0500) Subject: drm/msm/dpu: cast crtc_clk calculation to u64 in _dpu_core_perf_calc_clk() X-Git-Tag: v5.15.174~381 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=65aec8dc425dbcb02353f38a861a359d5fc3df3a;p=thirdparty%2Fkernel%2Fstable.git drm/msm/dpu: cast crtc_clk calculation to u64 in _dpu_core_perf_calc_clk() [ Upstream commit 20c7b42d9dbd048019bfe0af39229e3014007a98 ] There may be a potential integer overflow issue in _dpu_core_perf_calc_clk(). crtc_clk is defined as u64, while mode->vtotal, mode->hdisplay, and drm_mode_vrefresh(mode) are defined as a smaller data type. The result of the calculation will be limited to "int" in this case without correct casting. In screen with high resolution and high refresh rate, integer overflow may happen. So, we recommend adding an extra cast to prevent potential integer overflow. Fixes: c33b7c0389e1 ("drm/msm/dpu: add support for clk and bw scaling for display") Signed-off-by: Zichen Xie Reviewed-by: Abhinav Kumar Patchwork: https://patchwork.freedesktop.org/patch/622206/ Link: https://lore.kernel.org/r/20241029194209.23684-1-zichenxie0106@gmail.com Signed-off-by: Dmitry Baryshkov Signed-off-by: Sasha Levin --- diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c index 60fe06018581c..32dc298eb593e 100644 --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c @@ -80,7 +80,7 @@ static u64 _dpu_core_perf_calc_clk(struct dpu_kms *kms, mode = &state->adjusted_mode; - crtc_clk = mode->vtotal * mode->hdisplay * drm_mode_vrefresh(mode); + crtc_clk = (u64)mode->vtotal * mode->hdisplay * drm_mode_vrefresh(mode); drm_atomic_crtc_for_each_plane(plane, crtc) { pstate = to_dpu_plane_state(plane->state);