A well-formed NFSv4 ACL will always contain OWNER@/GROUP@/EVERYONE@
ACEs, but there is no requirement for inheritable entries for those
entities. POSIX ACLs must always have owner/group/other entries, even for a
default ACL.
nfsd builds the default ACL from inheritable ACEs, but the current code
just leaves any unspecified ACEs zeroed out. The result is that adding a
default user or group ACE to an inode can leave it with unwanted deny
entries.
For instance, a newly created directory with no acl will look something
like this:
# NFSv4 translation by server
A::OWNER@:rwaDxtTcCy
A::GROUP@:rxtcy
A::EVERYONE@:rxtcy
# POSIX ACL of underlying file
user::rwx
group::r-x
other::r-x
...if I then add new v4 ACE:
nfs4_setfacl -a A:fd:1000:rwx /mnt/local/test
...I end up with a result like this today:
user::rwx
user:1000:rwx
group::r-x
mask::rwx
other::r-x
default:user::---
default:user:1000:rwx
default:group::---
default😷:rwx
default:other::---
A::OWNER@:rwaDxtTcCy
A::1000:rwaDxtcy
A::GROUP@:rxtcy
A::EVERYONE@:rxtcy
D:fdi:OWNER@:rwaDx
A:fdi:OWNER@:tTcCy
A:fdi:1000:rwaDxtcy
A:fdi:GROUP@:tcy
A:fdi:EVERYONE@:tcy
...which is not at all expected. Adding a single inheritable allow ACE
should not result in everyone else losing access.
The setfacl command solves a silimar issue by copying owner/group/other
entries from the effective ACL when none of them are set:
"If a Default ACL entry is created, and the Default ACL contains no
owner, owning group, or others entry, a copy of the ACL owner,
owning group, or others entry is added to the Default ACL.
Having nfsd do the same provides a more sane result (with no deny ACEs
in the resulting set):
user::rwx
user:1000:rwx
group::r-x
mask::rwx
other::r-x
default:user::rwx
default:user:1000:rwx
default:group::r-x
default😷:rwx
default:other::r-x
A::OWNER@:rwaDxtTcCy
A::1000:rwaDxtcy
A::GROUP@:rxtcy
A::EVERYONE@:rxtcy
A:fdi:OWNER@:rwaDxtTcCy
A:fdi:1000:rwaDxtcy
A:fdi:GROUP@:rxtcy
A:fdi:EVERYONE@:rxtcy
Reported-by: Ondrej Valousek <ondrej.valousek@diasemi.com>
Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2136452
Suggested-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
d424797032