K 10
svn:author
V 3
kib
K 8
svn:date
V 27
2019-02-08T04:18:17.443185Z
K 7
svn:log
V 685
Fix renameat(2) for CAPABILITIES kernels.

When renameat(2) is used with:
- absolute path for to;
- tofd not set to AT_FDCWD;
- the target exists
kern_renameat() requires CAP_UNLINK capability on tofd, but
corresponding namei ni_filecap is not initialized at all because the
lookup is absolute.  As result, the check was done against empty filecap
and syscall fails erronously.

Fix it by creating a return flags namei member and reporting if the
lookup was absolute, then do not touch to.ni_filecaps at all.

PR:	222258
Reviewed by:	jilles, ngie
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
X-MFC-note:	KBI breakage
Differential revision:	https://reviews.freebsd.org/D19096

END