This is a note to let you know that I've just added the patch titled virtio-blk: fix implicit overflow on virtio_max_dma_size to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: virtio-blk-fix-implicit-overflow-on-virtio_max_dma_s.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit bca31ff5bc45b85b2081a424b1095dd57cef0f18 Author: zhenwei pi <pizhenwei@xxxxxxxxxxxxx> Date: Mon Sep 4 14:10:45 2023 +0800 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 <pizhenwei@xxxxxxxxxxxxx> Message-Id: <20230904061045.510460-1-pizhenwei@xxxxxxxxxxxxx> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index d2ba849bb8d19..affeca0dbc7ea 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -743,6 +743,7 @@ 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", @@ -844,7 +845,8 @@ static int virtblk_probe(struct virtio_device *vdev) /* No real sector limit. */ blk_queue_max_hw_sectors(q, -1U); - 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. */