1.8 KiB
CVE-2024-58099
Description
In the Linux kernel, the following vulnerability has been resolved:vmxnet3: Fix packet corruption in vmxnet3_xdp_xmit_frameAndrew and Nikolay reported connectivity issues with Cilium's serviceload-balancing in case of vmxnet3.If a BPF program for native XDP adds an encapsulation header such asIPIP and transmits the packet out the same interface, then in caseof vmxnet3 a corrupted packet is being sent and subsequently droppedon the path.vmxnet3_xdp_xmit_frame() which is called e.g. via vmxnet3_run_xdp()through vmxnet3_xdp_xmit_back() calculates an incorrect DMA address: page = virt_to_page(xdpf->data); tbi->dma_addr = page_pool_get_dma_addr(page) + VMXNET3_XDP_HEADROOM; dma_sync_single_for_device(&adapter->pdev->dev, tbi->dma_addr, buf_size, DMA_TO_DEVICE);The above assumes a fixed offset (VMXNET3_XDP_HEADROOM), but the XDPBPF program could have moved xdp->data. While the passed buf_size iscorrect (xdpf->len), the dma_addr needs to have a dynamic offset whichcan be calculated as xdpf->data - (void *)xdpf, that is, xdp->data -xdp->data_hard_start.
POC
Reference
No PoCs from references.