patch "staging: iio: frequency: ad9834: Validate frequency parameter value" added to char-misc-linus

This is a note to let you know that I've just added the patch titled

staging: iio: frequency: ad9834: Validate frequency parameter value

to my char-misc git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From b48aa991758999d4e8f9296c5bbe388f293ef465 Mon Sep 17 00:00:00 2001
From: Aleksandr Mishin <[email protected]>
Date: Wed, 3 Jul 2024 18:45:06 +0300
Subject: staging: iio: frequency: ad9834: Validate frequency parameter value

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.

---
 drivers/staging/iio/frequency/ad9834.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index a7a5cdcc6590..47e7d7e6d920 100644
@@ -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);

2.46.0