From d667fe301dcbcb12d1d6494fc4b8abee2cb75d90 Mon Sep 17 00:00:00 2001 From: zhenwei pi Date: Mon, 4 Sep 2023 14:10:45 +0800 Subject: [PATCH] virtio-blk: fix implicit overflow on virtio_max_dma_size [ Upstream commit fafb51a67fb883eb2dde352539df939a251851be ] The following codes have an implicit conversion from size_t to u32: (u32)max_size = (size_t)virtio_max_dma_size(vdev); This may lead overflow, Ex (size_t)4G -> (u32)0. Once virtio_max_dma_size() has a larger size than U32_MAX, use U32_MAX instead. Signed-off-by: zhenwei pi Message-Id: <20230904061045.510460-1-pizhenwei@bytedance.com> Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin --- drivers/block/virtio_blk.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 1fe0116..4a4b9ba 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -1313,6 +1313,7 @@ static int virtblk_probe(struct virtio_device *vdev) u16 min_io_size; u8 physical_block_exp, alignment_offset; unsigned int queue_depth; + size_t max_dma_size; if (!vdev->config->get) { dev_err(&vdev->dev, "%s failure: config access disabled\n", @@ -1411,7 +1412,8 @@ static int virtblk_probe(struct virtio_device *vdev) /* No real sector limit. */ blk_queue_max_hw_sectors(q, UINT_MAX); - max_size = virtio_max_dma_size(vdev); + max_dma_size = virtio_max_dma_size(vdev); + max_size = max_dma_size > U32_MAX ? U32_MAX : max_dma_size; /* Host can optionally specify maximum segment size and number of * segments. */ -- 2.7.4