Re: [PATCH v7 11/12] vduse: Introduce VDUSE - vDPA Device in Userspace
From: Al Viro <viro@zeniv.linux.org.uk>
Date: 2021-05-20 06:28:53
Also in:
kvm, linux-fsdevel, linux-iommu, lkml, netdev
On Mon, May 17, 2021 at 05:55:12PM +0800, Xie Yongji wrote:
+ case VDUSE_IOTLB_GET_FD: {
+ struct vduse_iotlb_entry entry;
+ struct vhost_iotlb_map *map;
+ struct vdpa_map_file *map_file;
+ struct vduse_iova_domain *domain = dev->domain;
+ struct file *f = NULL;
+
+ ret = -EFAULT;
+ if (copy_from_user(&entry, argp, sizeof(entry)))
+ break;return -EFAULT; surely?
+ + ret = -EINVAL; + if (entry.start > entry.last) + break;
... and similar here, etc.
+ spin_lock(&domain->iotlb_lock);
+ map = vhost_iotlb_itree_first(domain->iotlb,
+ entry.start, entry.last);
+ if (map) {
+ map_file = (struct vdpa_map_file *)map->opaque;
+ f = get_file(map_file->file);
+ entry.offset = map_file->offset;
+ entry.start = map->start;
+ entry.last = map->last;
+ entry.perm = map->perm;
+ }
+ spin_unlock(&domain->iotlb_lock);
+ ret = -EINVAL;
+ if (!f)
+ break;
+
+ ret = -EFAULT;
+ if (copy_to_user(argp, &entry, sizeof(entry))) {
+ fput(f);
+ break;
+ }
+ ret = receive_fd(f, perm_to_file_flags(entry.perm));
+ fput(f);
+ break;IDGI. The main difference between receive_fd() and plain old get_unused_fd_flags() + fd_install() is __receive_sock() call. Which does nothing whatsoever in case of non-sockets. Can you get a socket here? IOW, why bother with that crap at all, nevermind exporting it? _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization