The patch below does not apply to the 4.16-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From cdb3db8542d854bd678d60cd28861b042e191672 Mon Sep 17 00:00:00 2001 From: Jani Nikula <jani.nikula@xxxxxxxxx> Date: Wed, 14 Feb 2018 19:38:40 +0200 Subject: [PATCH] drm/i915/audio: fix check for av_enc_map overflow Turns out -1 >= ARRAY_SIZE() is always true. Move the bounds check where we know pipe >= 0 and next to the array indexing where it makes most sense. Fixes: 9965db26ac05 ("drm/i915: Check for fused or unused pipes") Fixes: 0b7029b7e43f ("drm/i915: Check for fused or unused pipes") Cc: <stable@xxxxxxxxxxxxxxx> # v4.10+ Cc: Mika Kahola <mika.kahola@xxxxxxxxx> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@xxxxxxxxx> Reviewed-by: Mika Kahola <mika.kahola@xxxxxxxxx> Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20180214173840.25360-1-jani.nikula@xxxxxxxxx diff --git a/drivers/gpu/drm/i915/intel_audio.c b/drivers/gpu/drm/i915/intel_audio.c index ff455c724775..709d6ca68074 100644 --- a/drivers/gpu/drm/i915/intel_audio.c +++ b/drivers/gpu/drm/i915/intel_audio.c @@ -779,11 +779,11 @@ static struct intel_encoder *get_saved_enc(struct drm_i915_private *dev_priv, { struct intel_encoder *encoder; - if (WARN_ON(pipe >= ARRAY_SIZE(dev_priv->av_enc_map))) - return NULL; - /* MST */ if (pipe >= 0) { + if (WARN_ON(pipe >= ARRAY_SIZE(dev_priv->av_enc_map))) + return NULL; + encoder = dev_priv->av_enc_map[pipe]; /* * when bootup, audio driver may not know it is