qemu: Don't update physical storage size of empty drives

Previously the code called virStorageSourceUpdateBlockPhysicalSize which
did not do anything on empty drives since it worked only on block
devices. After the refactor in c5f6151390 it's called for all devices
and thus attempts to deref the NULL path of empty drives.

Add a check that skips the update of the physical size if the storage
source is empty.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1420718

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 6e1e3d40888e67aa7b260bc00c97197378cddbd0..77d81755a3b45c73cad58460a184ff8c16547b95 100644 (file)
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -11336,6 +11336,9 @@ qemuDomainStorageUpdatePhysical(virQEMUDriverPtr driver,
     int fd = -1;
     struct stat sb;
 
+    if (virStorageSourceIsEmpty(src))
+        return 0;
+
     if (qemuDomainStorageOpenStat(driver, cfg, vm, src, &fd, &sb) < 0)
         return -1;