static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock,
			    struct msghdr *msg, size_t ignored, int flags)
{
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);
	struct skcipher_ctx *ctx = ask->private;
	unsigned bs = crypto_ablkcipher_blocksize(crypto_ablkcipher_reqtfm(
		&ctx->req));
	struct skcipher_sg_list *sgl;
	struct scatterlist *sg;
	unsigned long iovlen;
	struct iovec *iov;
	int err = -EAGAIN;
	int used;
	long copied = 0;

	lock_sock(sk);
	msg->msg_namelen = 0;
	for (iov = msg->msg_iov, iovlen = msg->msg_iovlen; iovlen > 0;
	     iovlen--, iov++) {
		unsigned long seglen = iov->iov_len;
		char __user *from = iov->iov_base;

		while (seglen) {
			sgl = list_first_entry(&ctx->tsgl,
					       struct skcipher_sg_list, list);
			sg = sgl->sg;

			while (!sg->length)
				sg++;

			used = ctx->used;
			if (!used) {
				err = skcipher_wait_for_data(sk, flags);
				if (err)
					goto unlock;
			}

			used = min_t(unsigned long, used, seglen);

			used = af_alg_make_sg(&ctx->rsgl, from, used, 1);
			err = used;
			if (err < 0)
				goto unlock;

			if (ctx->more || used < ctx->used)
				used -= used % bs;

			err = -EINVAL;
			if (!used)
				goto free;

			ablkcipher_request_set_crypt(&ctx->req, sg,
						     ctx->rsgl.sg, used,
						     ctx->iv);

			err = af_alg_wait_for_completion(
				ctx->enc ?
					crypto_ablkcipher_encrypt(&ctx->req) :
					crypto_ablkcipher_decrypt(&ctx->req),
				&ctx->completion);

free:
			af_alg_free_sg(&ctx->rsgl);

			if (err)
				goto unlock;

			copied += used;
			from += used;
			seglen -= used;
			skcipher_pull_sgl(sk, used);
		}
	}

	err = 0;

unlock:
	skcipher_wmem_wakeup(sk);
	release_sock(sk);

	return copied ?: err;
}
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