To work around a misbehavior of the compiler's ability to see into composite flexible array structs (as detailed in the coming memcpy() hardening series[1]), split the memcpy() of the header and the payload so no false positive run-time overflow warning will be generated. [1] https://lore.kernel.org/linux-hardening/20220901065914.1417829-2-keescook@xxxxxxxxxxxx Cc: Maximilian Luz <luzmaximilian@xxxxxxxxx> Cc: Hans de Goede <hdegoede@xxxxxxxxxx> Cc: Mark Gross <markgross@xxxxxxxxxx> Cc: platform-driver-x86@xxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- drivers/platform/surface/surface_acpi_notify.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/platform/surface/surface_acpi_notify.c b/drivers/platform/surface/surface_acpi_notify.c index 44e317970557..50500e562963 100644 --- a/drivers/platform/surface/surface_acpi_notify.c +++ b/drivers/platform/surface/surface_acpi_notify.c @@ -355,7 +355,8 @@ static u32 san_evt_bat_nf(struct ssam_event_notifier *nf, INIT_DELAYED_WORK(&work->work, san_evt_bat_workfn); work->dev = d->dev; - memcpy(&work->event, event, sizeof(struct ssam_event) + event->length); + work->event = *event; + memcpy(work->event.data, event->data, event->length); queue_delayed_work(san_wq, &work->work, delay); return SSAM_NOTIF_HANDLED; -- 2.34.1
