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x86_64-redhat-linux-gnu) MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: Fb6qiBjhLYGdzzlrX7AT-U8S50dIosaT5HclIEgTJ7k_1759180673 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: E87ADA001A X-Stat-Signature: 5fwcrbpwsqjs94xpe7gc3ngkn3j7inf8 X-Rspam-User: X-HE-Tag: 1759180678-657283 X-HE-Meta: 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 zsPaM3pT 1wQ2wBECPwPCSdaKbyY8iXawy0t8q/fyFz1JDr8bk6NxA7Cpq1KrodUNjHymE5j0gIFV+skH7TXibhS8DLaa4nuMLdGdl3fXK0yrgiBDOiMc/kCPWnmIQAbd3ITksakYP5VQMQiQmFKGI0l5CrNJn8Zbr42ORu+Uj+JcvntD/JPdKdCYO1xAXKDe+awOjuCN8SzyoPovbVYebhpLfNYB13K4M3Hy4C2KtftHcXhO/4hbOZ7N3yqTn+pMSauaDwuukBt0nUbV8IYPECrEIdm2zUftIWHYhK2C3d8mGAFZ36VqkWZmrmg+EcPxk7FdLJCyv8LcVhdb2FZ2AhDCvJqdevMErs/o3Q43dJO1Z0WcY3B7+5BwTfyQzQqay7A== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sun, 28 Sep 2025 17:50:20 +0300 Leon Romanovsky wrote: > +static int validate_dmabuf_input(struct vfio_pci_core_device *vdev, > + struct vfio_device_feature_dma_buf *dma_buf, > + struct vfio_region_dma_range *dma_ranges, > + struct p2pdma_provider **provider) > +{ > + struct pci_dev *pdev = vdev->pdev; > + u32 bar = dma_buf->region_index; > + resource_size_t bar_size; > + u64 sum; > + int i; > + > + if (dma_buf->flags) > + return -EINVAL; > + /* > + * For PCI the region_index is the BAR number like everything else. > + */ > + if (bar >= VFIO_PCI_ROM_REGION_INDEX) > + return -ENODEV; > + > + *provider = pcim_p2pdma_provider(pdev, bar); > + if (!provider) This needs to be IS_ERR_OR_NULL() or the function needs to settle on a consistent error return value regardless of CONFIG_PCI_P2PDMA. > + return -EINVAL; > + > + bar_size = pci_resource_len(pdev, bar); We get to this feature via vfio_pci_core_ioctl_feature(), which is used by several variant drivers, some of which mangle the BAR size exposed to the user, ex. hisi_acc. I'm afraid this might actually be giving dmabuf access to a portion of the BAR that isn't exposed otherwise. > + for (i = 0; i < dma_buf->nr_ranges; i++) { > + u64 offset = dma_ranges[i].offset; > + u64 len = dma_ranges[i].length; > + > + if (!PAGE_ALIGNED(offset) || !PAGE_ALIGNED(len)) > + return -EINVAL; > + > + if (check_add_overflow(offset, len, &sum) || sum > bar_size) > + return -EINVAL; > + } > + > + return 0; > +} > + > +int vfio_pci_core_feature_dma_buf(struct vfio_pci_core_device *vdev, u32 flags, > + struct vfio_device_feature_dma_buf __user *arg, > + size_t argsz) > +{ > + struct vfio_device_feature_dma_buf get_dma_buf = {}; > + struct vfio_region_dma_range *dma_ranges; > + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); > + struct p2pdma_provider *provider; > + struct vfio_pci_dma_buf *priv; > + int ret; > + > + ret = vfio_check_feature(flags, argsz, VFIO_DEVICE_FEATURE_GET, > + sizeof(get_dma_buf)); > + if (ret != 1) > + return ret; > + > + if (copy_from_user(&get_dma_buf, arg, sizeof(get_dma_buf))) > + return -EFAULT; > + > + if (!get_dma_buf.nr_ranges) > + return -EINVAL; > + > + dma_ranges = memdup_array_user(&arg->dma_ranges, get_dma_buf.nr_ranges, > + sizeof(*dma_ranges)); > + if (IS_ERR(dma_ranges)) > + return PTR_ERR(dma_ranges); > + > + ret = validate_dmabuf_input(vdev, &get_dma_buf, dma_ranges, &provider); > + if (ret) > + return ret; goto err_free_ranges; Thanks, Alex