The patch below does not apply to the 4.15-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 72a6d72c2cd03bba7b70117b63dea83d2de88057 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
(cherry picked from commit cdb3db8542d854bd678d60cd28861b042e191672)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
diff --git a/drivers/gpu/drm/i915/intel_audio.c b/drivers/gpu/drm/i915/intel_audio.c
index 522d54fecb53..4a01f62a392d 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