From: Edwin Török Date: Fri, 15 Jan 2021 19:38:58 +0000 (+0000) Subject: tools/oxenstored: mkdir conflicts were sometimes missed X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=955c60401a62bcdd0549bec958eaae4f9f17fb89;p=xen.git tools/oxenstored: mkdir conflicts were sometimes missed Due to how set_write_lowpath was used here it didn't detect create/delete conflicts. When we create an entry we must mark our parent as modified (this is what creating a new node via write does). Otherwise we can have 2 transactions one creating, and another deleting a node both succeeding depending on timing. Or one transaction reading an entry, concluding it doesn't exist, do some other work based on that information and successfully commit even if another transaction creates the node via mkdir meanwhile. Signed-off-by: Edwin Török Acked-by: Christian Lindig Release-Acked-by: Ian Jackson (cherry picked from commit 45dee7d92b493bb531e7e77a6f9c0180ab152f87) --- diff --git a/tools/ocaml/xenstored/transaction.ml b/tools/ocaml/xenstored/transaction.ml index 25bc8c3b4a..17b1bdf2ea 100644 --- a/tools/ocaml/xenstored/transaction.ml +++ b/tools/ocaml/xenstored/transaction.ml @@ -165,7 +165,7 @@ let write t perm path value = let mkdir ?(with_watch=true) t perm path = Store.mkdir t.store perm path; - set_write_lowpath t path; + set_write_lowpath t (Store.Path.get_parent path); if with_watch then add_wop t Xenbus.Xb.Op.Mkdir path