staging: iio: frequency: ad9832: fix division by zero in ad9832_calc_freqreg()

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: staging: iio: frequency: ad9832: fix division by zero in ad9832_calc_freqreg() 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.

References

• https://git.kernel.org/stable/c/fcd6b59f7a774558e2525251c68aa37aff748e55
• https://git.kernel.org/stable/c/442f786c5bff8cfd756ebdeaa4aadbf05c22aa5a
• https://git.kernel.org/stable/c/2f39548f45693d86e950647012a214da6917dc9f
• https://git.kernel.org/stable/c/ccbc10647aafe2b7506edb4b10e19c6c2416c162
• https://git.kernel.org/stable/c/adfbc08b94e7df08b9ed5fa26b969cc1b54c84ec
• https://git.kernel.org/stable/c/dd9e1cf619c945f320e686dcaf13e37ef0b05fdd
• https://git.kernel.org/stable/c/6bd301819f8f69331a55ae2336c8b111fc933f3d