[PATCH 1/2] ASoC: codecs: ad193x: Fix memory corruption on BE 64b systems

From: Codrin Ciubotariu
Date: Wed Jun 26 2019 - 06:50:11 EST


Since change_bit() requires unsigned long*, making this cast on an
unsigned int variable will change a wrong bit on BE platforms, causing
memory corruption. Replace this function with a simple XOR.

Fixes: 90f6e6803139 ("ASoC: codecs: ad193x: Fix frame polarity for DSP_A format")
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@xxxxxxxxxxxxx>
---
sound/soc/codecs/ad193x.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/sound/soc/codecs/ad193x.c b/sound/soc/codecs/ad193x.c
index 05f4514048e2..3ebc0524f4b2 100644
--- a/sound/soc/codecs/ad193x.c
+++ b/sound/soc/codecs/ad193x.c
@@ -240,10 +240,8 @@ static int ad193x_set_dai_fmt(struct snd_soc_dai *codec_dai,
}

/* For DSP_*, LRCLK's polarity must be inverted */
- if (fmt & SND_SOC_DAIFMT_DSP_A) {
- change_bit(ffs(AD193X_DAC_LEFT_HIGH) - 1,
- (unsigned long *)&dac_fmt);
- }
+ if (fmt & SND_SOC_DAIFMT_DSP_A)
+ dac_fmt ^= AD193X_DAC_LEFT_HIGH;

switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
case SND_SOC_DAIFMT_CBM_CFM: /* codec clk & frm master */
--
2.20.1