CVE-2024-50195: posix-clock: Fix missing timespec64 check in pc_clock_settime()

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

posix-clock: Fix missing timespec64 check in pcclocksettime()

As Andrew pointed out, it will make sense that the PTP core checked timespec64 struct's tvsec and tvnsec range before calling ptp-info-settime64().

As the man manual of clocksettime() said, if tp.tvsec is negative or tp.tvnsec is outside the range [0..999,999,999], it should return EINVAL, which include dynamic clocks which handles PTP clock, and the condition is consistent with timespec64valid(). As Thomas suggested, timespec64valid() only check the timespec is valid, but not ensure that the time is in a valid range, so check it ahead using timespec64validstrict() in pcclocksettime() and return -EINVAL if not valid.

There are some drivers that use tp-tvsec and tp-tvnsec directly to write registers without validity checks and assume that the higher layer has checked it, which is dangerous and will benefit from this, such as hclgeptpsettime(), igbptpsettimei210(), rcargen4ptpsettime(), and some drivers can remove the checks of itself.

— IBM

This CVE was automatically created from a reference found in an email or other text. If you are reading this, then this CVE entry is probably erroneous, since this text should be replaced by the official CVE description automatically.

— Launchpad