From 6cf3ab38b0d53d41f00fe594b2986849bdf994ae Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Thu, 8 Oct 2026 11:51:22 +0300 Subject: [PATCH] ALSA: hda/hdmi: clamp num_cvts against cvt_nids[] in hdmi_read_pin_conn hdmi_add_cvt() stores each converter's NID into the fixed-size spec->cvt_nids[] array (used only by the Intel Haswell pin-connection fixup), but only when spec->num_cvts is still within ARRAY_SIZE(cvt_nids); the num_cvts counter itself is incremented unconditionally regardless of whether the store happened. A codec that reports more converters than cvt_nids[] can hold therefore ends up with num_cvts > ARRAY_SIZE(cvt_nids). hdmi_read_pin_conn(), on the intel_hsw_fixup path, copies num_cvts elements from cvt_nids[] with memcpy(), so once num_cvts exceeds the array size this reads past cvt_nids[] and writes the resulting garbage NIDs into per_pin->mux_nids[]. Clamp the copy length to the actual size of cvt_nids[] instead of trusting num_cvts, which is also used unbounded as the size of the separate, dynamically-sized spec->cvts array and must not be truncated at the source. Fixes: bce0d2a80e42 ("ALSA: hda - Allow unlimited pins and converters in patch_hdmi.c") Cc: stable@vger.kernel.org Signed-off-by: Peter Ujfalusi Link: https://patch.msgid.link/20261008085122.9442-1-peter.ujfalusi@linux.intel.com Signed-off-by: Takashi Iwai --- sound/hda/codecs/hdmi/hdmi.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/sound/hda/codecs/hdmi/hdmi.c b/sound/hda/codecs/hdmi/hdmi.c index a8aac0b36c73..355fd3e73183 100644 --- a/sound/hda/codecs/hdmi/hdmi.c +++ b/sound/hda/codecs/hdmi/hdmi.c @@ -983,7 +983,8 @@ static int hdmi_read_pin_conn(struct hda_codec *codec, int pin_idx) snd_hda_set_dev_select(codec, pin_nid, dev_id); if (spec->intel_hsw_fixup) { - conns = spec->num_cvts; + /* spec->cvt_nids[] only has ARRAY_SIZE(spec->cvt_nids) slots */ + conns = min_t(int, spec->num_cvts, ARRAY_SIZE(spec->cvt_nids)); memcpy(per_pin->mux_nids, spec->cvt_nids, sizeof(hda_nid_t) * conns); } else {