nfs_common: Update the translation between nfsv3 acls linux posix acls

- Use kuid_t and kgit in struct nfsacl_encode_desc.
- Convert from kuids and kgids when generating on the wire values.
- Convert on the wire values to kuids and kgids when read.
- Modify cmp_acl_entry to be type safe comparison on posix acls.
  Only acls with type ACL_USER and ACL_GROUP can appear more
  than once and as such need to compare more than their tag.
- The e_id field is being removed from posix acls so don't initialize it.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

diff --git a/fs/nfs_common/nfsacl.c b/fs/nfs_common/nfsacl.c
index 6940439..ed628f7 100644 (file)
--- a/fs/nfs_common/nfsacl.c
+++ b/fs/nfs_common/nfsacl.c
@@ -38,8 +38,8 @@ struct nfsacl_encode_desc {
        unsigned int count;
        struct posix_acl *acl;
        int typeflag;
-       uid_t uid;
-       gid_t gid;
+       kuid_t uid;
+       kgid_t gid;
 };
 
 struct nfsacl_simple_acl {
@@ -60,14 +60,16 @@ xdr_nfsace_encode(struct xdr_array2_desc *desc, void *elem)
        *p++ = htonl(entry->e_tag | nfsacl_desc->typeflag);
        switch(entry->e_tag) {
                case ACL_USER_OBJ:
-                       *p++ = htonl(nfsacl_desc->uid);
+                       *p++ = htonl(from_kuid(&init_user_ns, nfsacl_desc->uid));
                        break;
                case ACL_GROUP_OBJ:
-                       *p++ = htonl(nfsacl_desc->gid);
+                       *p++ = htonl(from_kgid(&init_user_ns, nfsacl_desc->gid));
                        break;
                case ACL_USER:
+                       *p++ = htonl(from_kuid(&init_user_ns, entry->e_uid));
+                       break;
                case ACL_GROUP:
-                       *p++ = htonl(entry->e_id);
+                       *p++ = htonl(from_kgid(&init_user_ns, entry->e_gid));
                        break;
                default:  /* Solaris depends on that! */
                        *p++ = 0;
@@ -148,6 +150,7 @@ xdr_nfsace_decode(struct xdr_array2_desc *desc, void *elem)
                (struct nfsacl_decode_desc *) desc;
        __be32 *p = elem;
        struct posix_acl_entry *entry;
+       unsigned int id;
 
        if (!nfsacl_desc->acl) {
                if (desc->array_len > NFS_ACL_MAX_ENTRIES)
@@ -160,14 +163,22 @@ xdr_nfsace_decode(struct xdr_array2_desc *desc, void *elem)
 
        entry = &nfsacl_desc->acl->a_entries[nfsacl_desc->count++];
        entry->e_tag = ntohl(*p++) & ~NFS_ACL_DEFAULT;
-       entry->e_id = ntohl(*p++);
+       id = ntohl(*p++);
        entry->e_perm = ntohl(*p++);
 
        switch(entry->e_tag) {
-               case ACL_USER_OBJ:
                case ACL_USER:
-               case ACL_GROUP_OBJ:
+                       entry->e_uid = make_kuid(&init_user_ns, id);
+                       if (!uid_valid(entry->e_uid))
+                               return -EINVAL;
+                       break;
                case ACL_GROUP:
+                       entry->e_gid = make_kgid(&init_user_ns, id);
+                       if (!gid_valid(entry->e_gid))
+                               return -EINVAL;
+                       break;
+               case ACL_USER_OBJ:
+               case ACL_GROUP_OBJ:
                case ACL_OTHER:
                        if (entry->e_perm & ~S_IRWXO)
                                return -EINVAL;
@@ -190,9 +201,13 @@ cmp_acl_entry(const void *x, const void *y)
 
        if (a->e_tag != b->e_tag)
                return a->e_tag - b->e_tag;
-       else if (a->e_id > b->e_id)
+       else if ((a->e_tag == ACL_USER) && uid_gt(a->e_uid, b->e_uid))
+               return 1;
+       else if ((a->e_tag == ACL_USER) && uid_lt(a->e_uid, b->e_uid))
+               return -1;
+       else if ((a->e_tag == ACL_GROUP) && gid_gt(a->e_gid, b->e_gid))
                return 1;
-       else if (a->e_id < b->e_id)
+       else if ((a->e_tag == ACL_GROUP) && gid_lt(a->e_gid, b->e_gid))
                return -1;
        else
                return 0;
@@ -213,22 +228,18 @@ posix_acl_from_nfsacl(struct posix_acl *acl)
        sort(acl->a_entries, acl->a_count, sizeof(struct posix_acl_entry),
             cmp_acl_entry, NULL);
 
-       /* Clear undefined identifier fields and find the ACL_GROUP_OBJ
-          and ACL_MASK entries. */
+       /* Find the ACL_GROUP_OBJ and ACL_MASK entries. */
        FOREACH_ACL_ENTRY(pa, acl, pe) {
                switch(pa->e_tag) {
                        case ACL_USER_OBJ:
-                               pa->e_id = ACL_UNDEFINED_ID;
                                break;
                        case ACL_GROUP_OBJ:
-                               pa->e_id = ACL_UNDEFINED_ID;
                                group_obj = pa;
                                break;
                        case ACL_MASK:
                                mask = pa;
                                /* fall through */
                        case ACL_OTHER:
-                               pa->e_id = ACL_UNDEFINED_ID;
                                break;
                }
        }