Commit fb7609c4bf for qemu.org

commit fb7609c4bf74e31ea06c0d8e400dd01badcfa4c3
Author: Mohammadfaiz Bawa <mbawa@redhat.com>
Date:   Fri Jun 19 15:01:38 2026 +0530

    hw/core/platform-bus: guard platform_bus_get_mmio_addr() against NULL

    sysbus_mmio_get_region() returns NULL when a device has fewer MMIO
    regions than the requested slot index.  platform_bus_get_mmio_addr()
    passes the result directly to memory_region_is_mapped() without a
    NULL check, causing a SIGSEGV.

    Return -1 early when the region pointer is NULL, consistent with the
    existing "not mapped" path.

    Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
    Signed-off-by: Mohammadfaiz Bawa <mbawa@redhat.com>
    Link: https://lore.kernel.org/qemu-devel/20260619093140.832136-2-mbawa@redhat.com
    Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>

diff --git a/hw/core/platform-bus.c b/hw/core/platform-bus.c
index a2217a2dee..16d0ecc0f3 100644
--- a/hw/core/platform-bus.c
+++ b/hw/core/platform-bus.c
@@ -59,8 +59,7 @@ hwaddr platform_bus_get_mmio_addr(PlatformBusDevice *pbus, SysBusDevice *sbdev,
     Object *pbus_mr_obj = OBJECT(pbus_mr);
     Object *parent_mr;

-    if (!memory_region_is_mapped(sbdev_mr)) {
-        /* Region is not mapped? */
+    if (!sbdev_mr || !memory_region_is_mapped(sbdev_mr)) {
         return -1;
     }