CVE-2024-43825 iio: Fix the sorting functionality in iio_gts_build_avail_time_table

In the Linux kernel, the following vulnerability has been resolved:

iio: Fix the sorting functionality in iio_gts_build_avail_time_table

The sorting in iio_gts_build_avail_time_table is not working as intended.
It could result in an out-of-bounds access when the time is zero.

Here are more details:

1. When the gts->itime_table[i].time_us is zero, e.g., the time
   sequence is 3, 0, 1, the inner for-loop will not terminate and do
   out-of-bound writes. This is because once times[j] > new, the value
   new will be added in the current position and the times[j] will be
   moved to j+1 position, which makes the if-condition always hold.
   Meanwhile, idx will be added one, making the loop keep running without
   termination and out-of-bound write.
2. If none of the gts->itime_table[i].time_us is zero, the elements
   will just be copied without being sorted as described in the comment
   “Sort times from all tables to one and remove duplicates”.

For more details, please refer to
https://lore.kernel.org/all/[email protected].