kern/60801: hfs confuses ctime with birthtime

["campbell+netbsd%mumble.net@localhost via gnats" <gnats-admin%NetBSD.org@localhost>]

>Number:         60801
>Category:       kern
>Synopsis:       hfs confuses ctime with birthtime
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Sep 26 15:10:00 +0000 2026
>Originator:     Taylor R Campbell
>Release:        current, 11, 10, ...
>Organization:
The NetHFS+ Foundabug, Inctime.
>Environment:
>Description:

	hfs reports `date_created' as ctime, and doesn't report
	birthtime:

    612 		hfs_time_to_timespec(f->date_created, &vap->va_ctime);
    613 		hfs_time_to_timespec(f->date_content_mod, &vap->va_mtime);
    614 		hfs_time_to_timespec(f->date_accessed, &vap->va_atime);

	https://nxr.netbsd.org/xref/src/sys/fs/hfs/hfs_vnops.c?r=1.40#612

	(Likewise for directories.)

	But presumably `date_created' is supposed to mean birthtime,
	not file attribute change time, i.e., ctime.  These appear to
	be recorded separately in HFS:

    363 	uint32_t		date_created;
    364 	uint32_t		date_content_mod;
    365 	uint32_t		date_attrib_mod;
    366 	uint32_t		date_accessed;
    367 	uint32_t		date_backedup;

	https://nxr.netbsd.org/xref/src/sys/fs/hfs/libhfs.h?r=1.9#363

>How-To-Repeat:

	code inspection

>Fix:

	Yes, please!