From c4eb651db9b31a8c56395eb9f812bfc9d567a100 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= <philmd@linaro.org>
Date: Thu, 4 Apr 2024 20:56:35 +0200
Subject: [PATCH] hw/char/virtio-serial-bus: Protect from DMA re-entrancy
 bugs(CVE-2024-3446)
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Replace qemu_bh_new_guarded() by virtio_bh_new_guarded()
so the bus and device use the same guard. Otherwise the
DMA-reentrancy protection can be bypassed.

Fixes: CVE-2024-3446
Cc: qemu-stable@nongnu.org
Suggested-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20240409105537.18308-4-philmd@linaro.org>
Signed-off-by: liuxiangdong <liuxiangdong5@huawei.com>
---
 hw/char/virtio-serial-bus.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c
index a614810985..cb8417ee35 100644
--- a/hw/char/virtio-serial-bus.c
+++ b/hw/char/virtio-serial-bus.c
@@ -940,8 +940,7 @@ static void virtser_port_device_realize(DeviceState *dev, Error **errp)
     Error *err = NULL;
 
     port->vser = bus->vser;
-    port->bh = qemu_bh_new_guarded(flush_queued_data_bh, port,
-                                   &dev->mem_reentrancy_guard);
+    port->bh = virtio_bh_new_guarded(dev, flush_queued_data_bh, port);
 
     assert(vsc->have_data);
 
-- 
2.27.0

