[PATCH 5.15 014/107] ALSA: hda: intel-nhlt: Correct the handling of fmt_config flexible array

Greg Kroah-Hartman
2022-09-06T13:46:37Z

From: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>

[ Upstream commit 2e6481a3f3ee6234ce577454e1d88aca55f51d47 ]

The struct nhlt_format's fmt_config is a flexible array, it must not be
used as normal array.
When moving to the next nhlt_fmt_cfg we need to take into account the data
behind the ->config.caps (indicated by ->config.size).

Fixes: a864e8f159b13 ("ALSA: hda: intel-nhlt: verify config type")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Jaska Uimonen <jaska.uimonen@linux.intel.com>
Link: https://lore.kernel.org/r/20220823122405.18464-1-peter.ujfalusi@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
sound/hda/intel-nhlt.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/sound/hda/intel-nhlt.c b/sound/hda/intel-nhlt.c
index 5e04fedaec49e..8714891f50b0a 100644
--- a/sound/hda/intel-nhlt.c
+++ b/sound/hda/intel-nhlt.c
@@ -55,16 +55,22 @@ int intel_nhlt_get_dmic_geo(struct device *dev, struct nhlt_acpi_table *nhlt)

/* find max number of channels based on format_configuration */
if (fmt_configs->fmt_count) {
+ struct nhlt_fmt_cfg *fmt_cfg = fmt_configs->fmt_config;
+
dev_dbg(dev, "found %d format definitions\n",
fmt_configs->fmt_count);

for (i = 0; i < fmt_configs->fmt_count; i++) {
struct wav_fmt_ext *fmt_ext;

- fmt_ext = &fmt_configs->fmt_config[i].fmt_ext;
+ fmt_ext = &fmt_cfg->fmt_ext;

if (fmt_ext->fmt.channels > max_ch)
max_ch = fmt_ext->fmt.channels;
+
+ /* Move to the next nhlt_fmt_cfg */
+ fmt_cfg = (struct nhlt_fmt_cfg *)(fmt_cfg->config.caps +
+ fmt_cfg->config.size);
}
dev_dbg(dev, "max channels found %d\n", max_ch);
} else {
--
2.35.1