From d8b09a5edc4a634373158c1a405491de3c52e58a Mon Sep 17 00:00:00 2001 From: Aleksandr Mishin Date: Wed, 3 Jul 2024 18:45:06 +0300 Subject: [PATCH] staging: iio: frequency: ad9834: Validate frequency parameter value commit b48aa991758999d4e8f9296c5bbe388f293ef465 upstream. 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 Signed-off-by: Aleksandr Mishin Reviewed-by: Dan Carpenter Link: https://patch.msgid.link/20240703154506.25584-1-amishin@t-argos.ru Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- 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 94b131ef8a22..d78454deedd9 100644 --- a/drivers/staging/iio/frequency/ad9834.c +++ b/drivers/staging/iio/frequency/ad9834.c @@ -114,7 +114,7 @@ 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);