nfsd: Fix sort_pacl in fs/nfsd/nf4acl.c to actually sort groups

commit aba24d71580180dfdf6a1a83a5858a1c048fd785 upstream.

We have been doing some extensive testing of Linux support for ACLs on
NFDS v4. We have noticed that the server rejects ACLs where the groups
are out of order, for example, the following ACL is rejected:

A::OWNER@:rwaxtTcCy
A::user101@domain:rwaxtcy
A::GROUP@:rwaxtcy
A:g:group102@domain:rwaxtcy
A:g:group101@domain:rwaxtcy
A::EVERYONE@:rwaxtcy

Examining the server code, I found that after converting an NFS v4 ACL
to POSIX, sort_pacl is called to sort the user ACEs and group ACEs.
Unfortunately, a minor bug causes the group sort to be skipped.

Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/nfsd/nfs4acl.c b/fs/nfsd/nfs4acl.c
index 725d02f210e272bc3c99306c1e2400f201095fb5..6d9c6aabc85e2fe8ce458309f61880685501f02f 100644 (file)
--- a/fs/nfsd/nfs4acl.c
+++ b/fs/nfsd/nfs4acl.c
@@ -389,7 +389,7 @@ sort_pacl(struct posix_acl *pacl)
        sort_pacl_range(pacl, 1, i-1);
 
        BUG_ON(pacl->a_entries[i].e_tag != ACL_GROUP_OBJ);
-       j = i++;
+       j = ++i;
        while (pacl->a_entries[j].e_tag == ACL_GROUP)
                j++;
        sort_pacl_range(pacl, i, j-1);