diff options
| author | Zicheng Qu <quzicheng@huawei.com> | 2024-10-22 13:43:54 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-11-08 16:20:53 +0100 |
| commit | fcd6b59f7a774558e2525251c68aa37aff748e55 (patch) | |
| tree | b7a2f530edb244bdb152f14855b50e7c7bb289e4 | |
| parent | 9d89941e51259c2b0b8e9c10c6f1f74200d7444f (diff) | |
staging: iio: frequency: ad9832: fix division by zero in ad9832_calc_freqreg()
commit 6bd301819f8f69331a55ae2336c8b111fc933f3d upstream.
In the ad9832_write_frequency() function, clk_get_rate() might return 0.
This can lead to a division by zero when calling ad9832_calc_freqreg().
The check if (fout > (clk_get_rate(st->mclk) / 2)) does not protect
against the case when fout is 0. The ad9832_write_frequency() function
is called from ad9832_write(), and fout is derived from a text buffer,
which can contain any value.
Link: https://lore.kernel.org/all/2024100904-CVE-2024-47663-9bdc@gregkh/
Fixes: ea707584bac1 ("Staging: IIO: DDS: AD9832 / AD9835 driver")
Cc: stable@vger.kernel.org
Signed-off-by: Zicheng Qu <quzicheng@huawei.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/20241022134354.574614-1-quzicheng@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/staging/iio/frequency/ad9832.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/staging/iio/frequency/ad9832.c b/drivers/staging/iio/frequency/ad9832.c index 74308a2e72db..d4e04f439865 100644 --- a/drivers/staging/iio/frequency/ad9832.c +++ b/drivers/staging/iio/frequency/ad9832.c @@ -129,12 +129,15 @@ static unsigned long ad9832_calc_freqreg(unsigned long mclk, unsigned long fout) static int ad9832_write_frequency(struct ad9832_state *st, unsigned int addr, unsigned long fout) { + unsigned long clk_freq; unsigned long regval; - if (fout > (clk_get_rate(st->mclk) / 2)) + clk_freq = clk_get_rate(st->mclk); + + if (!clk_freq || fout > (clk_freq / 2)) return -EINVAL; - regval = ad9832_calc_freqreg(clk_get_rate(st->mclk), fout); + regval = ad9832_calc_freqreg(clk_freq, fout); st->freq_data[0] = cpu_to_be16((AD9832_CMD_FRE8BITSW << CMD_SHIFT) | (addr << ADD_SHIFT) | |