[PATCH 5.16 006/126] ASoC: hdmi-codec: Fix OOB memory accesses

Greg Kroah-Hartman
2022-02-07T12:03:24Z

From: Dmitry Osipenko <digetx@gmail.com>

commit 06feec6005c9d9500cd286ec440aabf8b2ddd94d upstream.

Correct size of iec_status array by changing it to the size of status
array of the struct snd_aes_iec958. This fixes out-of-bounds slab
read accesses made by memcpy() of the hdmi-codec driver. This problem
is reported by KASAN.

Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20220112195039.1329-1-digetx@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/uapi/sound/asound.h | 4 +++-
sound/soc/codecs/hdmi-codec.c | 2 +-
2 files changed, 4 insertions(+), 2 deletions(-)

--- a/include/uapi/sound/asound.h
+++ b/include/uapi/sound/asound.h
@@ -56,8 +56,10 @@
* *
****************************************************************************/

+#define AES_IEC958_STATUS_SIZE 24
+
struct snd_aes_iec958 {
- unsigned char status[24]; /* AES/IEC958 channel status bits */
+ unsigned char status[AES_IEC958_STATUS_SIZE]; /* AES/IEC958 channel status bits */
unsigned char subcode[147]; /* AES/IEC958 subcode bits */
unsigned char pad; /* nothing */
unsigned char dig_subframe[4]; /* AES/IEC958 subframe bits */
--- a/sound/soc/codecs/hdmi-codec.c
+++ b/sound/soc/codecs/hdmi-codec.c
@@ -277,7 +277,7 @@ struct hdmi_codec_priv {
bool busy;
struct snd_soc_jack *jack;
unsigned int jack_status;
- u8 iec_status[5];
+ u8 iec_status[AES_IEC958_STATUS_SIZE];
};

static const struct snd_soc_dapm_widget hdmi_widgets[] = {