https://codeberg.org/guix/guix/issues/3925 raised the inabilityy of the
subordinate IDs service of handling externally managed sub{u,g}id file
entries. This patch relaxes the checks in place for existing ranges,
by allowing subid-range records lower than %subordinate-id-min, leaving
all the space from subid 0 to %subordinate-id-min - 1 to external
users. Generic ranges are still allocated within %subordinate-id-min and
%subordinate-id-max.
* gnu/build/accounts.scm (<unused-id-range>)[min]: Change default value
to 0, allowing subid-ranges with a start lesser than
%subordinate-id-min.
(allocate-generic-range): Allocate generic ranges starting from
%subordinate-id-min, leaving ranges starting before %subordinate-id-min.
(allocate-specific-range): Move bounds check to...
(allocate-subids): ...here. Now bound validation is applied only to user
provided ranges.
* tests/accounts.scm: Test new behavior.
Fixes: guix/guix#3925
Change-Id: Id923b122c97a20f148684f5fb144fd9422810612
Signed-off-by: Ludovic Courtès <ludo@gnu.org>
Merges: #4235
fdb46ae7b1