[PATCH] [v2] ASoC: cros_ec_codec: fix uninitialized memory read

From: Arnd Bergmann
Date: Fri Dec 04 2020 - 03:37:12 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

gcc points out a memory area that is copied to a device
but not initialized:

sound/soc/codecs/cros_ec_codec.c: In function 'i2s_rx_event':
arch/x86/include/asm/string_32.h:83:20: error: '*((void *)&p+4)' may be used uninitialized in this function [-Werror=maybe-uninitialized]
83 | *((int *)to + 1) = *((int *)from + 1);

Change the length of the command to only pass down the
part of the structure that has been initialized, as
Tzung-Bi Shih explains that only that member is meant to
be used.

Cc: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
Fixes: 727f1c71c780 ("ASoC: cros_ec_codec: refactor I2S RX")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
sound/soc/codecs/cros_ec_codec.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/codecs/cros_ec_codec.c b/sound/soc/codecs/cros_ec_codec.c
index 58894bf47514..6ec673573c70 100644
--- a/sound/soc/codecs/cros_ec_codec.c
+++ b/sound/soc/codecs/cros_ec_codec.c
@@ -348,7 +348,7 @@ static int i2s_rx_event(struct snd_soc_dapm_widget *w,
}

return send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_I2S_RX,
- (uint8_t *)&p, sizeof(p), NULL, 0);
+ &p.cmd, sizeof(p.cmd), NULL, 0);
}

static struct snd_soc_dapm_widget i2s_rx_dapm_widgets[] = {
--
2.27.0