From: Igor Mammedov <imamm...@redhat.com> If host_memory_backend_get_memory() were to return error and NULL MemoryRegion, pc_dimm_check_memdev_is_busy() would crash dereferencing NULL pointer in memory_region_is_mapped(). But if error is set and non NULL MemoryRegion is returned then error_setg() will fail with "error already set" assertion in error_setv()
To avoid above issues use typical error handling pattern for property setters: Error *local_error = NULL; ... error_propagate(errp, local_err); Reported-by: Markus Armbruster <arm...@redhat.com> Signed-off-by: Igor Mammedov <imamm...@redhat.com> Reviewed-by: Markus Armbruster <arm...@redhat.com> Reviewed-by: Michael S. Tsirkin <m...@redhat.com> Signed-off-by: Michael S. Tsirkin <m...@redhat.com> --- hw/mem/pc-dimm.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c index 650f0f8..973bf20 100644 --- a/hw/mem/pc-dimm.c +++ b/hw/mem/pc-dimm.c @@ -364,15 +364,22 @@ static void pc_dimm_check_memdev_is_busy(Object *obj, const char *name, Object *val, Error **errp) { MemoryRegion *mr; + Error *local_err = NULL; - mr = host_memory_backend_get_memory(MEMORY_BACKEND(val), errp); + mr = host_memory_backend_get_memory(MEMORY_BACKEND(val), &local_err); + if (local_err) { + goto out; + } if (memory_region_is_mapped(mr)) { char *path = object_get_canonical_path_component(val); - error_setg(errp, "can't use already busy memdev: %s", path); + error_setg(&local_err, "can't use already busy memdev: %s", path); g_free(path); } else { - qdev_prop_allow_set_link_before_realize(obj, name, val, errp); + qdev_prop_allow_set_link_before_realize(obj, name, val, &local_err); } + +out: + error_propagate(errp, local_err); } static void pc_dimm_init(Object *obj) -- MST