Merge branch 'io_uring-7.0' into for-next

* io_uring-7.0:
  io_uring/rsrc: reject zero-length fixed buffer import
  io_uring/net: fix slab-out-of-bounds read in io_bundle_nbufs()

Author: axboe

io_uring/net.c

@@ -425,6 +425,8 @@ int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 
 	sr->done_io = 0;
 	sr->len = READ_ONCE(sqe->len);
+	if (unlikely(sr->len < 0))
+		return -EINVAL;
 	sr->flags = READ_ONCE(sqe->ioprio);
 	if (sr->flags & ~SENDMSG_FLAGS)
 		return -EINVAL;
@@ -795,6 +797,8 @@ int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 
 	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
 	sr->len = READ_ONCE(sqe->len);
+	if (unlikely(sr->len < 0))
+		return -EINVAL;
 	sr->flags = READ_ONCE(sqe->ioprio);
 	if (sr->flags & ~RECVMSG_FLAGS)
 		return -EINVAL;

io_uring/rsrc.c

@@ -1061,6 +1061,10 @@ static int io_import_fixed(int ddir, struct iov_iter *iter,
 		return ret;
 	if (!(imu->dir & (1 << ddir)))
 		return -EFAULT;
+	if (unlikely(!len)) {
+		iov_iter_bvec(iter, ddir, NULL, 0, 0);
+		return 0;
+	}
 
 	offset = buf_addr - imu->ubuf;