[PATCH 1/3] tools/oxenstored: Fix quota calculation for mkdir EEXIST

[Andrew Cooper <andrew.cooper3@citrix.com>]

From: Edwin Török <edvin.torok@citrix.com>

We increment the domain's quota on mkdir even when the node already exists.
This results in a quota inconsistency after live update, where reconstructing
the tree from scratch results in a different quota.

Not a security issue because the domain uses up quota faster, so it will only
get a Quota error sooner than it should.

Found by the structured fuzzer.

Signed-off-by: Edwin Török <edvin.torok@citrix.com>
---
CC: Christian Lindig <christian.lindig@citrix.com>
CC: Ian Jackson <iwj@xenproject.org>
CC: Wei Liu <wl@xen.org>
---
 tools/ocaml/xenstored/store.ml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/ocaml/xenstored/store.ml b/tools/ocaml/xenstored/store.ml
index 1bd0c81f6f..20e67b1427 100644
--- a/tools/ocaml/xenstored/store.ml
+++ b/tools/ocaml/xenstored/store.ml
@@ -419,6 +419,7 @@ let mkdir store perm path =
 	(* It's upt to the mkdir logic to decide what to do with existing path *)
 	if not (existing || (Perms.Connection.is_dom0 perm)) then Quota.check store.quota owner 0;
 	store.root <- path_mkdir store perm path;
+	if not existing then
 	Quota.add_entry store.quota owner
 
 let rm store perm path =
-- 
2.11.0