[Qemu-devel] [PATCH for-2.6] ivshmem: fix crash with ivshmem-plain

[marcandre.lureau@redhat.com]

From: Marc-André Lureau <marcandre.lureau@redhat.com>

"qemu -device ivshmem-plain" will crash, because it doesn't check that
'memdev' was provided.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 hw/misc/ivshmem.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
index 08bf5c6..fae4d08 100644
--- a/hw/misc/ivshmem.c
+++ b/hw/misc/ivshmem.c
@@ -868,7 +868,7 @@ static void ivshmem_common_realize(PCIDevice *dev, Error **errp)
 
         s->ivshmem_bar2 = host_memory_backend_get_memory(s->hostmem,
                                                          &error_abort);
-    } else {
+    } else if (s->server_chr) {
         IVSHMEM_DPRINTF("using shared memory server (socket = %s)\n",
                         s->server_chr->filename);
 
@@ -899,6 +899,8 @@ static void ivshmem_common_realize(PCIDevice *dev, Error **errp)
             error_setg(errp, "failed to initialize interrupts");
             return;
         }
+    } else {
+        g_assert_not_reached();
     }
 
     vmstate_register_ram(s->ivshmem_bar2, DEVICE(s));
@@ -1048,10 +1050,25 @@ static void ivshmem_plain_init(Object *obj)
                              &error_abort);
 }
 
+static void ivshmem_plain_realize(PCIDevice *dev, Error **errp)
+{
+    IVShmemState *s = IVSHMEM_COMMON(dev);
+
+    if (!s->hostmem) {
+        error_setg(errp, "You must specify a 'memdev'");
+        return;
+    }
+
+    ivshmem_common_realize(dev, errp);
+}
+
+
 static void ivshmem_plain_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
+    PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
 
+    k->realize = ivshmem_plain_realize;
     dc->props = ivshmem_plain_properties;
     dc->vmsd = &ivshmem_plain_vmsd;
 }
-- 
2.5.5