[libvirt] [PATCHv2] qemu: fix crash in migrate when migrateuri do not have a scheme

[Luyao Huang]

https://bugzilla.redhat.com/show_bug.cgi?id=1191355

When we migrate a vm with migrateuri option with a uri do not
have scheme like this:

 # virsh migrate test4 --live qemu+ssh://lhuang/system --migrateuri 127.0.0.1

target libvirtd will crashed because uri->scheme is NULL in
qemuMigrationPrepareDirect this line:

     if (STRNEQ(uri->scheme, "tcp") &&

add a value check before this line. Also fix a place like this in
doNativeMigrate.

Signed-off-by: Luyao Huang <lhuang at redhat.com>
---
 src/qemu/qemu_migration.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index 879b1bf..d4ffe6c 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -3281,6 +3281,13 @@ qemuMigrationPrepareDirect(virQEMUDriverPtr driver,
         if (!(uri = qemuMigrationParseURI(uri_in, &well_formed_uri)))
             goto cleanup;
 
+        if (uri->scheme == NULL) {
+            virReportError(VIR_ERR_INVALID_ARG,
+                           _("missing scheme in migration URI: %s"),
+                           uri_in);
+            goto cleanup;
+        }
+
         if (STRNEQ(uri->scheme, "tcp") &&
             STRNEQ(uri->scheme, "rdma")) {
             virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED,
@@ -4083,6 +4090,13 @@ static int doNativeMigrate(virQEMUDriverPtr driver,
     if (!(uribits = qemuMigrationParseURI(uri, NULL)))
         return -1;
 
+    if (uribits->scheme == NULL) {
+        virReportError(VIR_ERR_INVALID_ARG,
+                       _("missing scheme in migration URI: %s"),
+                       uri);
+        goto cleanup;
+    }
+
     if (STREQ(uribits->scheme, "rdma")) {
         if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATE_RDMA)) {
             virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
-- 
1.8.3.1