On 06/26/2014 07:51 AM, Eric Blake wrote:
From: Peter Krempa <pkrempa(a)redhat.com>
When creating a new disk mirror the new struct is stored in a separate
variable until everything went well. The removed hunk would actually
remove existing mirror information for example when the api would be run
if a mirror still exists.
(cherry picked from commit 02b364e186d487f54ed410c01af042f23e812d42)
This fixes a regression introduced in commit ff5f30b.
Signed-off-by: Eric Blake <eblake(a)redhat.com>
Conflicts:
src/qemu/qemu_driver.c - no refactoring of commit 7b7bf001
---
As Peter's patch resolves a regression, I'd like to backport it to
the maint branches; however, that means redoing the patch.
src/qemu/qemu_driver.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 59185c6..591864f 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -15203,6 +15203,7 @@ qemuDomainBlockCopy(virDomainObjPtr vm,
struct stat st;
bool need_unlink = false;
char *mirror = NULL;
+ int mirrorFormat;
Uninitialized...
virQEMUDriverConfigPtr cfg = NULL;
/* Preliminaries: find the disk we are editing, sanity checks */
@@ -15290,10 +15291,10 @@ qemuDomainBlockCopy(virDomainObjPtr vm,
goto endjob;
VIR_FORCE_CLOSE(fd);
if (!format)
- disk->mirrorFormat = disk->src.format;
+ mirrorFormat = disk->src.format;
but here, if the user did not request reusing a file but DID request
raw, mirrorFormat is still uninitialized...
} else if (format) {
- disk->mirrorFormat = virStorageFileFormatTypeFromString(format);
- if (disk->mirrorFormat <= 0) {
+ mirrorFormat = virStorageFileFormatTypeFromString(format);
+ if (mirrorFormat <= 0) {
virReportError(VIR_ERR_INVALID_ARG, _("unrecognized format
'%s'"),
format);
goto endjob;
@@ -15303,11 +15304,11 @@ qemuDomainBlockCopy(virDomainObjPtr vm,
* also passed the RAW flag (and format is non-NULL), or it is
* safe for us to probe the format from the file that we will
* be using. */
- disk->mirrorFormat = virStorageFileProbeFormat(dest, cfg->user,
- cfg->group);
+ mirrorFormat = virStorageFileProbeFormat(dest, cfg->user,
+ cfg->group);
}
- if (!format && disk->mirrorFormat > 0)
- format = virStorageFileFormatTypeToString(disk->mirrorFormat);
+ if (!format && mirrorFormat > 0)
+ format = virStorageFileFormatTypeToString(mirrorFormat);
and here we are using the uninitialized value :(
It looks like this has been broken ever since v1.0.0 (when blockcopy was
first introduced), so it is not a regression that we have been
mishandling 'virsh blockcopy $dom vda /path/to/file --raw', but
disk->mirrorFormat was at least initialized to 0 compared to my patch
using an uninitialized value. Peter will be proposing a patch soon,
which must make it into 1.2.6.
--
Eric Blake eblake redhat com +1-919-301-3266
Libvirt virtualization library
http://libvirt.org