From: Jani Nikula Date: Thu, 25 Jun 2026 17:03:04 +0000 (+0300) Subject: drm/i915/hdcp: check streams[] bounds before overflow X-Git-Tag: v7.2-rc2~10^2~3^2~3 X-Git-Url: http://git.ipfire.org/index.cgi?a=commitdiff_plain;h=bbb15a6b042d02e5508a02b4847e02d2579ee7bc;p=thirdparty%2Flinux.git drm/i915/hdcp: check streams[] bounds before overflow The data->streams[] overflow check is done after the buffer overflow has already happened. Move the overflow check before the write. Side note, emitting a warning splat with a backtrace might be overkill here, but prefer not changing the behaviour other than not doing the overrun. Discovered using AI-assisted static analysis confirmed by Intel Product Security. Reported-by: Martin Hodo Fixes: e03187e12cae ("drm/i915/hdcp: MST streams support in hdcp port_data") Cc: stable@vger.kernel.org # v5.12+ Cc: Anshuman Gupta Cc: Suraj Kandpal Reviewed-by: Suraj Kandpal Link: https://patch.msgid.link/20260625170304.1104723-1-jani.nikula@intel.com Signed-off-by: Jani Nikula (cherry picked from commit 9284ab3b6e776c315883ac2611283d263c9460fd) Signed-off-by: Joonas Lahtinen --- diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c index e88fec24af49..521786a75c42 100644 --- a/drivers/gpu/drm/i915/display/intel_hdcp.c +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c @@ -145,6 +145,9 @@ intel_hdcp_required_content_stream(struct intel_atomic_state *state, if (!new_conn_state || !new_conn_state->crtc) continue; + if (drm_WARN_ON(display->drm, data->k >= INTEL_NUM_PIPES(display))) + return -EINVAL; + data->streams[data->k].stream_id = intel_conn_to_vcpi(state, connector); data->k++; @@ -155,7 +158,7 @@ intel_hdcp_required_content_stream(struct intel_atomic_state *state, } drm_connector_list_iter_end(&conn_iter); - if (drm_WARN_ON(display->drm, data->k > INTEL_NUM_PIPES(display) || data->k == 0)) + if (drm_WARN_ON(display->drm, !data->k)) return -EINVAL; /*