4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Aleksandr Mishin <amishin@xxxxxxxxxx>
[ Upstream commit b48aa991758999d4e8f9296c5bbe388f293ef465 ]
In ad9834_write_frequency() clk_get_rate() can return 0. In such case
ad9834_calc_freqreg() call will lead to division by zero. Checking
'if (fout > (clk_freq / 2))' doesn't protect in case of 'fout' is 0.
ad9834_write_frequency() is called from ad9834_write(), where fout is
taken from text buffer, which can contain any value.
Modify parameters checking.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 12b9d5bf76bf ("Staging: IIO: DDS: AD9833 / AD9834 driver")
Suggested-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Aleksandr Mishin <amishin@xxxxxxxxxx>
Reviewed-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Link: https://patch.msgid.link/20240703154506.25584-1-amishin@xxxxxxxxxx
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/staging/iio/frequency/ad9834.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/staging/iio/frequency/ad9834.c b/drivers/staging/iio/frequency/ad9834.c
index 5e98ee5dfbdc..3eb089dc220e 100644
--- a/drivers/staging/iio/frequency/ad9834.c
+++ b/drivers/staging/iio/frequency/ad9834.c
@@ -116,7 +116,7 @@ static int ad9834_write_frequency(struct ad9834_state *st,
clk_freq = clk_get_rate(st->mclk);
- if (fout > (clk_freq / 2))
+ if (!clk_freq || fout > (clk_freq / 2))
return -EINVAL;
regval = ad9834_calc_freqreg(clk_freq, fout);
--
2.43.0
