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>
---
 include/uapi/sound/asound.h   | 4 +++-
 sound/soc/codecs/hdmi-codec.c | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/uapi/sound/asound.h b/include/uapi/sound/asound.h
index ef0cafe295b2..2d3e5df39a59 100644
--- 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 */
diff --git a/sound/soc/codecs/hdmi-codec.c b/sound/soc/codecs/hdmi-codec.c
index b61f980cabdc..b07607a9ecea 100644
--- 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[] = {
-- 
2.33.1

On Wed, 12 Jan 2022 22:50:39 +0300, Dmitry Osipenko wrote:
> 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.
> 
> 

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-linus

Thanks!

[1/1] ASoC: hdmi-codec: Fix OOB memory accesses
      commit: 06feec6005c9d9500cd286ec440aabf8b2ddd94d

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark