8:28 a.m.
See patch 1/2 for justification. Patch 2 is a test case.
Peter Krempa (2):
storage_file: Refuse qcow2 images with empty string as 'data_file'
virstoragetest: Add case for qcow2 image with empty string as
'data_file'
src/storage_file/storage_source.c | 10 ++++++++++
tests/virstoragetest.c | 5 +++++
.../images/datafile-emptystr.qcow2 | Bin 0 -> 327680 bytes
3 files changed, 15 insertions(+)
create mode 100644 tests/virstoragetestdata/images/datafile-emptystr.qcow2
--
2.47.1
8:28 a.m.
New subject: [PATCH 1/2] storage_file: Refuse qcow2 images with empty string as 'data_file'
In certain buggy conditions qemu can create an image which has empty
string stored as 'data_file'. While probing libvirt would consider the
empty string as a relative file name and construct the path using the
path of the parent image stripping the last component and appending the
empty string. This results into attempting to using a directory as an
image and thus the following error when attempting to start VM with such
an image:
error: unsupported configuration: storage type 'dir' requires use of storage
format 'fat'
Reject empty strings passed in as 'data_file'.
Note that we do not have the same problem with 'backing store' as an
empty string there is interpreted as no backing file both by qemu and
libvirt.
Resolves: https://issues.redhat.com/browse/RHEL-70627
Signed-off-by: Peter Krempa <pkrempa(a)redhat.com>
---
src/storage_file/storage_source.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/src/storage_file/storage_source.c b/src/storage_file/storage_source.c
index 4612e710b0..fa59949cf2 100644
--- a/src/storage_file/storage_source.c
+++ b/src/storage_file/storage_source.c
@@ -557,6 +557,16 @@ virStorageSourceNewFromDataFile(virStorageSource *parent)
g_autoptr(virStorageSource) dataFile = NULL;
int rc;
+ /* 'qemu-img' records an empty string as 'data_file' field in certain
buggy
+ * cases. Note that it can't happen for 'backing store' as absence of
the
+ * string equals to no backing store. */
+ if (STREQ(parent->dataFileRaw, "")) {
+ virReportError(VIR_ERR_OPERATION_FAILED,
+ _("invalid empty data-file definition in
'%1$s'"),
+ NULLSTR(parent->path));
+ return NULL;
+ }
+
if ((rc = virStorageSourceNewFromChild(parent,
parent->dataFileRaw,
&dataFile)) < 0)
--
2.47.1
8:28 a.m.
New subject: [PATCH 2/2] virstoragetest: Add case for qcow2 image with empty string as 'data_file'
Add an example image formatted by:
qemu-img create -f qcow2 -o
data_file=nbd+unix:///datafile?socket=/tmp/nbd,data_file_raw=true /tmp/nbddatastore.qcow2
10M -u
serving as an example when qemu records an empty string as the
'data_file' field.
Signed-off-by: Peter Krempa <pkrempa(a)redhat.com>
---
tests/virstoragetest.c | 5 +++++
.../images/datafile-emptystr.qcow2 | Bin 0 -> 327680 bytes
2 files changed, 5 insertions(+)
create mode 100644 tests/virstoragetestdata/images/datafile-emptystr.qcow2
diff --git a/tests/virstoragetest.c b/tests/virstoragetest.c
index 4ec837eefb..78dc644637 100644
--- a/tests/virstoragetest.c
+++ b/tests/virstoragetest.c
@@ -494,6 +494,11 @@ mymain(void)
abs_srcdir
"/virstoragetestdata/images/qcow2datafile-datafile.qcow2",
VIR_STORAGE_FILE_QCOW2, EXP_PASS);
+ /* broken qcow2 with a 'data_file' which is an empty string */
+ TEST_CHAIN("qcow2-datafile-broken",
+ abs_srcdir
"/virstoragetestdata/images/datafile-emptystr.qcow2",
+ VIR_STORAGE_FILE_QCOW2, EXP_FAIL);
+
/* Test various combinations of qcow2 images with missing 'backing_format'
*/
TEST_CHAIN("qcow2-qcow2_qcow2-qcow2_qcow2-auto",
abs_srcdir
"/virstoragetestdata/images/qcow2_qcow2-qcow2_qcow2-auto.qcow2",
diff --git a/tests/virstoragetestdata/images/datafile-emptystr.qcow2
b/tests/virstoragetestdata/images/datafile-emptystr.qcow2
new file mode 100644
index 0000000000000000000000000000000000000000..18fae8740b4d650252d9a20629ca6e4d04653692
GIT binary patch
literal 327680
zcmeIuK}y3w6b9f)+5>omoWUCuL=fBvg6p(NG0>(VouYNsV+(F1sS&bCUEA*q4D;Un
znPKMX{^2WxFbiWh=Q16-Nk17<=juF;&BtZGLDy@B{@vnv(am3HpD!UKrx1#&jmK<R
z#UU~+S?${P(8Ry~k(TeVZ0mfJ6?x3Fb+suc516fX+omn|`)XHb@z_kKLzs8_*F{-m
zkGEM_$F?f>69*(=lYbnuwp_1vhdNG0dudo!aho?6gFn)w&EK-oorfg=0000000000
z00000000000000000000000000000000000000000000000000000000000000000
z0D#NV%Mkzo0000000000000000000000000000000000000000000000000000000
z000000000000000000000RFk;_X7X`00000000000000000000000000000000000
z0000000000000000000000000000000000000000;EJ8PyU(xq0RR910000000000
z00000000000000000000000000000000000000000000000000000000000000000
z=$*U+000000000000000000000000000000000000000000000000000000000000
V0000000000000000000Xgm1%)GK2sC
literal 0
HcmV?d00001
--
2.47.1
5:48 a.m.
New subject: [PATCH 0/2] storage_file: Refuse qcow2 images with empty string
as 'data_file'
On 1/9/25 15:28, Peter Krempa wrote:
See patch 1/2 for justification. Patch 2 is a test case.
Peter Krempa (2):
storage_file: Refuse qcow2 images with empty string as 'data_file'
virstoragetest: Add case for qcow2 image with empty string as
'data_file'
src/storage_file/storage_source.c | 10 ++++++++++
tests/virstoragetest.c | 5 +++++
.../images/datafile-emptystr.qcow2 | Bin 0 -> 327680 bytes
3 files changed, 15 insertions(+)
create mode 100644 tests/virstoragetestdata/images/datafile-emptystr.qcow2
Reviewed-by: Michal Privoznik <mprivozn(a)redhat.com>
Michal
18
days inactive
22
days old
3 comments
2 participants
participants (2)
-
Michal Prívozník -
Peter Krempa