1 files changed, 112 insertions, 135 deletions

diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c
index d0cde541beb6..4d3dfc60a16a 100644
--- a/crypto/algif_hash.c
+++ b/crypto/algif_hash.c
@@ -1,15 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * algif_hash: User-space interface for hash algorithms
  *
  * This file provides the user-space API for hash algorithms.
  *
  * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; either version 2 of the License, or (at your option)
- * any later version.
- *
  */
 
 #include <crypto/hash.h>
@@ -68,121 +63,117 @@ static void hash_free_result(struct sock *sk, struct hash_ctx *ctx)
 static int hash_sendmsg(struct socket *sock, struct msghdr *msg,
 			size_t ignored)
 {
-	int limit = ALG_MAX_PAGES * PAGE_SIZE;
 	struct sock *sk = sock->sk;
 	struct alg_sock *ask = alg_sk(sk);
 	struct hash_ctx *ctx = ask->private;
-	long copied = 0;
+	ssize_t copied = 0;
+	size_t len, max_pages, npages;
+	bool continuing, need_init = false;
 	int err;
 
-	if (limit > sk->sk_sndbuf)
-		limit = sk->sk_sndbuf;
+	max_pages = min_t(size_t, ALG_MAX_PAGES,
+			  DIV_ROUND_UP(sk->sk_sndbuf, PAGE_SIZE));
 
 	lock_sock(sk);
-	if (!ctx->more) {
-		if ((msg->msg_flags & MSG_MORE))
-			hash_free_result(sk, ctx);
-
-		err = crypto_wait_req(crypto_ahash_init(&ctx->req), &ctx->wait);
-		if (err)
-			goto unlock;
-	}
-
-	ctx->more = 0;
-
-	while (msg_data_left(msg)) {
-		int len = msg_data_left(msg);
-
-		if (len > limit)
-			len = limit;
+	continuing = ctx->more;
 
-		len = af_alg_make_sg(&ctx->sgl, &msg->msg_iter, len);
-		if (len < 0) {
-			err = copied ? 0 : len;
-			goto unlock;
+	if (!continuing) {
+		/* Discard a previous request that wasn't marked MSG_MORE. */
+		hash_free_result(sk, ctx);
+		if (!msg_data_left(msg))
+			goto done; /* Zero-length; don't start new req */
+		need_init = true;
+	} else if (!msg_data_left(msg)) {
+		/*
+		 * No data - finalise the prev req if MSG_MORE so any error
+		 * comes out here.
+		 */
+		if (!(msg->msg_flags & MSG_MORE)) {
+			err = hash_alloc_result(sk, ctx);
+			if (err)
+				goto unlock_free_result;
+			ahash_request_set_crypt(&ctx->req, NULL,
+						ctx->result, 0);
+			err = crypto_wait_req(crypto_ahash_final(&ctx->req),
+					      &ctx->wait);
+			if (err)
+				goto unlock_free_result;
 		}
-
-		ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL, len);
-
-		err = crypto_wait_req(crypto_ahash_update(&ctx->req),
-				      &ctx->wait);
-		af_alg_free_sg(&ctx->sgl);
-		if (err)
-			goto unlock;
-
-		copied += len;
-		iov_iter_advance(&msg->msg_iter, len);
+		goto done_more;
 	}
 
-	err = 0;
+	while (msg_data_left(msg)) {
+		ctx->sgl.sgt.sgl = ctx->sgl.sgl;
+		ctx->sgl.sgt.nents = 0;
+		ctx->sgl.sgt.orig_nents = 0;
 
-	ctx->more = msg->msg_flags & MSG_MORE;
-	if (!ctx->more) {
-		err = hash_alloc_result(sk, ctx);
-		if (err)
-			goto unlock;
+		err = -EIO;
+		npages = iov_iter_npages(&msg->msg_iter, max_pages);
+		if (npages == 0)
+			goto unlock_free;
 
-		ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
-		err = crypto_wait_req(crypto_ahash_final(&ctx->req),
-				      &ctx->wait);
-	}
+		sg_init_table(ctx->sgl.sgl, npages);
 
-unlock:
-	release_sock(sk);
+		ctx->sgl.need_unpin = iov_iter_extract_will_pin(&msg->msg_iter);
 
-	return err ?: copied;
-}
-
-static ssize_t hash_sendpage(struct socket *sock, struct page *page,
-			     int offset, size_t size, int flags)
-{
-	struct sock *sk = sock->sk;
-	struct alg_sock *ask = alg_sk(sk);
-	struct hash_ctx *ctx = ask->private;
-	int err;
+		err = extract_iter_to_sg(&msg->msg_iter, LONG_MAX,
+					 &ctx->sgl.sgt, npages, 0);
+		if (err < 0)
+			goto unlock_free;
+		len = err;
+		sg_mark_end(ctx->sgl.sgt.sgl + ctx->sgl.sgt.nents - 1);
 
-	if (flags & MSG_SENDPAGE_NOTLAST)
-		flags |= MSG_MORE;
-
-	lock_sock(sk);
-	sg_init_table(ctx->sgl.sg, 1);
-	sg_set_page(ctx->sgl.sg, page, size, offset);
-
-	if (!(flags & MSG_MORE)) {
-		err = hash_alloc_result(sk, ctx);
-		if (err)
-			goto unlock;
-	} else if (!ctx->more)
-		hash_free_result(sk, ctx);
+		if (!msg_data_left(msg)) {
+			err = hash_alloc_result(sk, ctx);
+			if (err)
+				goto unlock_free;
+		}
 
-	ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, ctx->result, size);
+		ahash_request_set_crypt(&ctx->req, ctx->sgl.sgt.sgl,
+					ctx->result, len);
 
-	if (!(flags & MSG_MORE)) {
-		if (ctx->more)
-			err = crypto_ahash_finup(&ctx->req);
-		else
+		if (!msg_data_left(msg) && !continuing &&
+		    !(msg->msg_flags & MSG_MORE)) {
 			err = crypto_ahash_digest(&ctx->req);
-	} else {
-		if (!ctx->more) {
-			err = crypto_ahash_init(&ctx->req);
-			err = crypto_wait_req(err, &ctx->wait);
-			if (err)
-				goto unlock;
+		} else {
+			if (need_init) {
+				err = crypto_wait_req(
+					crypto_ahash_init(&ctx->req),
+					&ctx->wait);
+				if (err)
+					goto unlock_free;
+				need_init = false;
+			}
+
+			if (msg_data_left(msg) || (msg->msg_flags & MSG_MORE))
+				err = crypto_ahash_update(&ctx->req);
+			else
+				err = crypto_ahash_finup(&ctx->req);
+			continuing = true;
 		}
 
-		err = crypto_ahash_update(&ctx->req);
-	}
-
-	err = crypto_wait_req(err, &ctx->wait);
-	if (err)
-		goto unlock;
+		err = crypto_wait_req(err, &ctx->wait);
+		if (err)
+			goto unlock_free;
 
-	ctx->more = flags & MSG_MORE;
+		copied += len;
+		af_alg_free_sg(&ctx->sgl);
+	}
 
+done_more:
+	ctx->more = msg->msg_flags & MSG_MORE;
+done:
+	err = 0;
 unlock:
 	release_sock(sk);
+	return copied ?: err;
 
-	return err ?: size;
+unlock_free:
+	af_alg_free_sg(&ctx->sgl);
+unlock_free_result:
+	hash_free_result(sk, ctx);
+	ctx->more = false;
+	goto unlock;
 }
 
 static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
@@ -216,7 +207,7 @@ static int hash_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 	}
 
 	if (!result || ctx->more) {
-		ctx->more = 0;
+		ctx->more = false;
 		err = crypto_wait_req(crypto_ahash_final(&ctx->req),
 				      &ctx->wait);
 		if (err)
@@ -232,31 +223,38 @@ unlock:
 	return err ?: len;
 }
 
-static int hash_accept(struct socket *sock, struct socket *newsock, int flags,
-		       bool kern)
+static int hash_accept(struct socket *sock, struct socket *newsock,
+		       struct proto_accept_arg *arg)
 {
 	struct sock *sk = sock->sk;
 	struct alg_sock *ask = alg_sk(sk);
 	struct hash_ctx *ctx = ask->private;
 	struct ahash_request *req = &ctx->req;
-	char state[HASH_MAX_STATESIZE];
+	struct crypto_ahash *tfm;
 	struct sock *sk2;
 	struct alg_sock *ask2;
 	struct hash_ctx *ctx2;
+	char *state;
 	bool more;
 	int err;
 
+	tfm = crypto_ahash_reqtfm(req);
+	state = kmalloc(crypto_ahash_statesize(tfm), GFP_KERNEL);
+	err = -ENOMEM;
+	if (!state)
+		goto out;
+
 	lock_sock(sk);
 	more = ctx->more;
 	err = more ? crypto_ahash_export(req, state) : 0;
 	release_sock(sk);
 
 	if (err)
-		return err;
+		goto out_free_state;
 
-	err = af_alg_accept(ask->parent, newsock, kern);
+	err = af_alg_accept(ask->parent, newsock, arg);
 	if (err)
-		return err;
+		goto out_free_state;
 
 	sk2 = newsock->sk;
 	ask2 = alg_sk(sk2);
@@ -264,14 +262,14 @@ static int hash_accept(struct socket *sock, struct socket *newsock, int flags,
 	ctx2->more = more;
 
 	if (!more)
-		return err;
+		goto out_free_state;
 
 	err = crypto_ahash_import(&ctx2->req, state);
-	if (err) {
-		sock_orphan(sk2);
-		sock_put(sk2);
-	}
 
+out_free_state:
+	kfree_sensitive(state);
+
+out:
 	return err;
 }
 
@@ -284,14 +282,11 @@ static struct proto_ops algif_hash_ops = {
 	.ioctl		=	sock_no_ioctl,
 	.listen		=	sock_no_listen,
 	.shutdown	=	sock_no_shutdown,
-	.getsockopt	=	sock_no_getsockopt,
 	.mmap		=	sock_no_mmap,
 	.bind		=	sock_no_bind,
-	.setsockopt	=	sock_no_setsockopt,
 
 	.release	=	af_alg_release,
 	.sendmsg	=	hash_sendmsg,
-	.sendpage	=	hash_sendpage,
 	.recvmsg	=	hash_recvmsg,
 	.accept		=	hash_accept,
 };
@@ -306,7 +301,7 @@ static int hash_check_key(struct socket *sock)
 	struct alg_sock *ask = alg_sk(sk);
 
 	lock_sock(sk);
-	if (ask->refcnt)
+	if (!atomic_read(&ask->nokey_refcnt))
 		goto unlock_child;
 
 	psk = ask->parent;
@@ -318,11 +313,8 @@ static int hash_check_key(struct socket *sock)
 	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 		goto unlock;
 
-	if (!pask->refcnt++)
-		sock_hold(psk);
-
-	ask->refcnt = 1;
-	sock_put(psk);
+	atomic_dec(&pask->nokey_refcnt);
+	atomic_set(&ask->nokey_refcnt, 0);
 
 	err = 0;
 
@@ -346,18 +338,6 @@ static int hash_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
 	return hash_sendmsg(sock, msg, size);
 }
 
-static ssize_t hash_sendpage_nokey(struct socket *sock, struct page *page,
-				   int offset, size_t size, int flags)
-{
-	int err;
-
-	err = hash_check_key(sock);
-	if (err)
-		return err;
-
-	return hash_sendpage(sock, page, offset, size, flags);
-}
-
 static int hash_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
 			      size_t ignored, int flags)
 {
@@ -371,7 +351,7 @@ static int hash_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
 }
 
 static int hash_accept_nokey(struct socket *sock, struct socket *newsock,
-			     int flags, bool kern)
+			     struct proto_accept_arg *arg)
 {
 	int err;
 
@@ -379,7 +359,7 @@ static int hash_accept_nokey(struct socket *sock, struct socket *newsock,
 	if (err)
 		return err;
 
-	return hash_accept(sock, newsock, flags, kern);
+	return hash_accept(sock, newsock, arg);
 }
 
 static struct proto_ops algif_hash_ops_nokey = {
@@ -391,14 +371,11 @@ static struct proto_ops algif_hash_ops_nokey = {
 	.ioctl		=	sock_no_ioctl,
 	.listen		=	sock_no_listen,
 	.shutdown	=	sock_no_shutdown,
-	.getsockopt	=	sock_no_getsockopt,
 	.mmap		=	sock_no_mmap,
 	.bind		=	sock_no_bind,
-	.setsockopt	=	sock_no_setsockopt,
 
 	.release	=	af_alg_release,
 	.sendmsg	=	hash_sendmsg_nokey,
-	.sendpage	=	hash_sendpage_nokey,
 	.recvmsg	=	hash_recvmsg_nokey,
 	.accept		=	hash_accept_nokey,
 };
@@ -439,9 +416,8 @@ static int hash_accept_parent_nokey(void *private, struct sock *sk)
 	if (!ctx)
 		return -ENOMEM;
 
-	ctx->result = NULL;
+	memset(ctx, 0, len);
 	ctx->len = len;
-	ctx->more = 0;
 	crypto_init_wait(&ctx->wait);
 
 	ask->private = ctx;
@@ -490,4 +466,5 @@ static void __exit algif_hash_exit(void)
 
 module_init(algif_hash_init);
 module_exit(algif_hash_exit);
+MODULE_DESCRIPTION("Userspace interface for hash algorithms");
 MODULE_LICENSE("GPL");