From 33eaebe48e9215da6bc7d5bd426593821cc18cb9 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Fri, 6 Apr 2012 10:32:07 -0600 Subject: [PATCH] snapshot: sanity check when reusing file for snapshot The snapshot code when reusing an existing file had hard-to-read logic, as well as a missing sanity check: REUSE_EXT should require the destination to already be present. * src/qemu/qemu_driver.c (qemuDomainSnapshotDiskPrepare): Require destination on REUSE_EXT, rename variable for legibility. --- src/qemu/qemu_driver.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index d1dc2b8051..8af316fd71 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -10705,12 +10705,12 @@ qemuDomainSnapshotDiskPrepare(virDomainObjPtr vm, virDomainSnapshotDefPtr def, bool found = false; bool active = virDomainObjIsActive(vm); struct stat st; - bool allow_reuse = (*flags & VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT) != 0; + bool reuse = (*flags & VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT) != 0; bool atomic = (*flags & VIR_DOMAIN_SNAPSHOT_CREATE_ATOMIC) != 0; int external = 0; qemuDomainObjPrivatePtr priv = vm->privateData; - if (allow_reuse && !qemuCapsGet(priv->caps, QEMU_CAPS_TRANSACTION)) { + if (reuse && !qemuCapsGet(priv->caps, QEMU_CAPS_TRANSACTION)) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", _("reuse is not supported with this QEMU binary")); goto cleanup; @@ -10759,8 +10759,13 @@ qemuDomainSnapshotDiskPrepare(virDomainObjPtr vm, virDomainSnapshotDefPtr def, _("unable to stat for disk %s: %s"), disk->name, disk->file); goto cleanup; + } else if (reuse) { + virReportSystemError(errno, + _("missing existing file for disk %s: %s"), + disk->name, disk->file); + goto cleanup; } - } else if (!(S_ISBLK(st.st_mode) || !st.st_size || allow_reuse)) { + } else if (!S_ISBLK(st.st_mode) && st.st_size && !reuse) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, _("external snapshot file for disk %s already " "exists and is not a block device: %s"), -- 2.39.5