From 4dc123500c3bcdb834a3685bc412bf7e2813ea3f Mon Sep 17 00:00:00 2001 From: Mark Pearson Date: Tue, 2 Mar 2021 09:10:03 -0500 Subject: [PATCH] ALSA: hda: ignore invalid NHLT table [ Upstream commit a14a6219996ee6f6e858d83b11affc7907633687 ] On some Lenovo systems if the microphone is disabled in the BIOS only the NHLT table header is created, with no data. This means the endpoints field is not correctly set to zero - leading to an unintialised variable and hence invalid descriptors are parsed leading to page faults. The Lenovo firmware team is addressing this, but adding a check preventing invalid tables being parsed is worthwhile. Tested on a Lenovo T14. Tested-by: Philipp Leskovitz Reported-by: Philipp Leskovitz Signed-off-by: Mark Pearson Reviewed-by: Pierre-Louis Bossart Link: https://lore.kernel.org/r/20210302141003.7342-1-markpearson@lenovo.com Signed-off-by: Takashi Iwai Signed-off-by: Sasha Levin --- sound/hda/intel-nhlt.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/sound/hda/intel-nhlt.c b/sound/hda/intel-nhlt.c index d053beccfaec..e2237239d922 100644 --- a/sound/hda/intel-nhlt.c +++ b/sound/hda/intel-nhlt.c @@ -39,6 +39,11 @@ int intel_nhlt_get_dmic_geo(struct device *dev, struct nhlt_acpi_table *nhlt) if (!nhlt) return 0; + if (nhlt->header.length <= sizeof(struct acpi_table_header)) { + dev_warn(dev, "Invalid DMIC description table\n"); + return 0; + } + for (j = 0, epnt = nhlt->desc; j < nhlt->endpoint_count; j++, epnt = (struct nhlt_endpoint *)((u8 *)epnt + epnt->length)) {