From ee8a41cd30a99b39bd5d46280cc778e275cd2390 Mon Sep 17 00:00:00 2001 From: Fred Oh Date: Mon, 22 Jun 2020 10:13:48 -0500 Subject: [PATCH] ASoC: rt1011: fix KASAN out-of-bounds bug in find_next_bit() KASAN throws the following warning in rt1011.c: [ 170.777603] BUG: KASAN: stack-out-of-bounds in _find_next_bit.constprop.0+0x3e/0xf0 find_next_bit() relies on unsigned long pointer arguments, but this driver uses a type cast that generates the KASAN warning. Replace find_next_bit() and find_last_bit() with __ffs() and __fls() to pass the value and avoid casting pointers to make the warning go away. Signed-off-by: Fred Oh Signed-off-by: Pierre-Louis Bossart Reviewed-by: Guennadi Liakhovetski Link: https://lore.kernel.org/r/20200622151348.28063-1-pierre-louis.bossart@linux.intel.com Signed-off-by: Mark Brown --- sound/soc/codecs/rt1011.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/sound/soc/codecs/rt1011.c b/sound/soc/codecs/rt1011.c index dec5638060c3..098ecf13814d 100644 --- a/sound/soc/codecs/rt1011.c +++ b/sound/soc/codecs/rt1011.c @@ -1849,13 +1849,13 @@ static int rt1011_set_tdm_slot(struct snd_soc_dai *dai, /* Rx slot configuration */ rx_slotnum = hweight_long(rx_mask); - first_bit = find_next_bit((unsigned long *)&rx_mask, 32, 0); - if (rx_slotnum > 1 || rx_slotnum == 0) { + if (rx_slotnum > 1 || !rx_slotnum) { ret = -EINVAL; - dev_dbg(component->dev, "too many rx slots or zero slot\n"); + dev_err(component->dev, "too many rx slots or zero slot\n"); goto _set_tdm_err_; } + first_bit = __ffs(rx_mask); switch (first_bit) { case 0: case 2: @@ -1892,11 +1892,17 @@ static int rt1011_set_tdm_slot(struct snd_soc_dai *dai, /* Tx slot configuration */ tx_slotnum = hweight_long(tx_mask); - first_bit = find_next_bit((unsigned long *)&tx_mask, 32, 0); - last_bit = find_last_bit((unsigned long *)&tx_mask, 32); - if (tx_slotnum > 2 || (last_bit-first_bit) > 1) { + if (tx_slotnum > 2 || !tx_slotnum) { ret = -EINVAL; - dev_dbg(component->dev, "too many tx slots or tx slot location error\n"); + dev_err(component->dev, "too many tx slots or zero slot\n"); + goto _set_tdm_err_; + } + + first_bit = __ffs(tx_mask); + last_bit = __fls(tx_mask); + if (last_bit - first_bit > 1) { + ret = -EINVAL; + dev_err(component->dev, "tx slot location error\n"); goto _set_tdm_err_; } -- 2.11.0