[PATCH v10 28/46] richacl: Set the owner permissions to the owner mask

Andreas Gruenbacher
2015-10-11T23:02:28Z

In the write-through case, change the acl so that owner@ is granted the
permissions set in the owner mask (to match what the permission check
algorithm grants the owner).

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
---
fs/richacl_compat.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 46 insertions(+)

diff --git a/fs/richacl_compat.c b/fs/richacl_compat.c
index 7d007d7..16deeb4 100644
--- a/fs/richacl_compat.c
+++ b/fs/richacl_compat.c
@@ -416,3 +416,49 @@ richacl_propagate_everyone(struct richacl_alloc *alloc)
}
return 0;
}
+
+/**
+ * richacl_set_owner_permissions - set the owner permissions to the owner mask
+ *
+ * In the write-through case, change the acl so that owner@ is granted the
+ * permissions set in the owner mask (to match what the permission check
+ * algorithm grants the owner). This leaves at most one efective owner@ allow
+ * entry at the beginning of the acl.
+ */
+static int
+richacl_set_owner_permissions(struct richacl_alloc *alloc)
+{
+ unsigned int x = RICHACE_POSIX_ALWAYS_ALLOWED;
+ unsigned int owner_mask = alloc->acl->a_owner_mask & ~x;
+ unsigned int denied = 0;
+ struct richace *ace;
+
+ if (!((alloc->acl->a_flags & RICHACL_WRITE_THROUGH)))
+ return 0;
+
+ richacl_for_each_entry(ace, alloc->acl) {
+ if (richace_is_owner(ace)) {
+ if (richace_is_allow(ace) && !(owner_mask & denied)) {
+ richace_change_mask(alloc, &ace, owner_mask);
+ owner_mask = 0;
+ } else
+ richace_change_mask(alloc, &ace, 0);
+ } else {
+ if (richace_is_deny(ace))
+ denied |= ace->e_mask;
+ }
+ }
+
+ if (owner_mask & (denied |
+ ~alloc->acl->a_other_mask |
+ ~alloc->acl->a_group_mask)) {
+ ace = alloc->acl->a_entries;
+ if (richacl_insert_entry(alloc, &ace))
+ return -1;
+ ace->e_type = RICHACE_ACCESS_ALLOWED_ACE_TYPE;
+ ace->e_flags = RICHACE_SPECIAL_WHO;
+ ace->e_mask = owner_mask;
+ ace->e_id.special = RICHACE_OWNER_SPECIAL_ID;
+ }
+ return 0;