[libvirt] [PATCH] qemu: snapshot: Do ACL check prior to checkpoint interlocking

[Peter Krempa]

Commit 7efe930ec3c introduced interlock of snapshots and checkpoints,
but the check is executed prior to the snapshot API ACL check. This
means that an unauthorized user can see whether a VM exists if it has a
checkpoint.

Move the checks to proper places.

Signed-off-by: Peter Krempa <pkrempa at redhat.com>
---

Given that currently checkpoints by themselves are not very useful I
doubt that there are users which could hit this. Thus I'm sending it
also directly to the public mailing list for faster turnaround.

 src/qemu/qemu_driver.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 0753904472..f7f059b6d6 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -15902,18 +15902,18 @@ qemuDomainSnapshotCreateXML(virDomainPtr domain,
     if (!(vm = qemuDomObjFromDomain(domain)))
         goto cleanup;

-    if (virDomainListCheckpoints(vm->checkpoints, NULL, domain, NULL, 0) > 0) {
-        virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
-                       _("cannot create snapshot while checkpoint exists"));
-        goto cleanup;
-    }
-
     priv = vm->privateData;
     cfg = virQEMUDriverGetConfig(driver);

     if (virDomainSnapshotCreateXMLEnsureACL(domain->conn, vm->def, flags) < 0)
         goto cleanup;

+    if (virDomainListCheckpoints(vm->checkpoints, NULL, domain, NULL, 0) > 0) {
+        virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
+                       _("cannot create snapshot while checkpoint exists"));
+        goto cleanup;
+    }
+
     if (!(caps = virQEMUDriverGetCapabilities(driver, false)))
         goto cleanup;

-- 
2.21.0