ALSA: hda: intel-nhlt: Correct the handling of fmt_config flexible array

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>

diff --git a/sound/hda/intel-nhlt.c b/sound/hda/intel-nhlt.c
index 9db5ccd..13bb0cc 100644 (file)
--- 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 {