1 files changed, 53 insertions, 45 deletions

diff --git a/net/bpfilter/bpfilter_kern.c b/net/bpfilter/bpfilter_kern.c
index 1905e01c3aa9..51a941b56ec3 100644
--- a/net/bpfilter/bpfilter_kern.c
+++ b/net/bpfilter/bpfilter_kern.c
@@ -15,15 +15,13 @@ extern char bpfilter_umh_end;
 
 static void shutdown_umh(void)
 {
-	struct task_struct *tsk;
+	struct umd_info *info = &bpfilter_ops.info;
+	struct pid *tgid = info->tgid;
 
-	if (bpfilter_ops.stop)
-		return;
-
-	tsk = get_pid_task(find_vpid(bpfilter_ops.info.pid), PIDTYPE_PID);
-	if (tsk) {
-		send_sig(SIGKILL, tsk, 1);
-		put_task_struct(tsk);
+	if (tgid) {
+		kill_pid(tgid, SIGKILL, 1);
+		wait_event(tgid->wait_pidfd, thread_group_exited(tgid));
+		bpfilter_umh_cleanup(info);
 	}
 }
 
@@ -33,60 +31,65 @@ static void __stop_umh(void)
 		shutdown_umh();
 }
 
-static int __bpfilter_process_sockopt(struct sock *sk, int optname,
-				      char __user *optval,
-				      unsigned int optlen, bool is_set)
+static int bpfilter_send_req(struct mbox_request *req)
 {
-	struct mbox_request req;
 	struct mbox_reply reply;
-	loff_t pos;
+	loff_t pos = 0;
 	ssize_t n;
-	int ret = -EFAULT;
-
-	req.is_set = is_set;
-	req.pid = current->pid;
-	req.cmd = optname;
-	req.addr = (long __force __user)optval;
-	req.len = optlen;
-	if (!bpfilter_ops.info.pid)
-		goto out;
-	n = kernel_write(bpfilter_ops.info.pipe_to_umh, &req, sizeof(req),
+
+	if (!bpfilter_ops.info.tgid)
+		return -EFAULT;
+	pos = 0;
+	n = kernel_write(bpfilter_ops.info.pipe_to_umh, req, sizeof(*req),
 			   &pos);
-	if (n != sizeof(req)) {
+	if (n != sizeof(*req)) {
 		pr_err("write fail %zd\n", n);
-		__stop_umh();
-		ret = -EFAULT;
-		goto out;
+		goto stop;
 	}
 	pos = 0;
 	n = kernel_read(bpfilter_ops.info.pipe_from_umh, &reply, sizeof(reply),
 			&pos);
 	if (n != sizeof(reply)) {
 		pr_err("read fail %zd\n", n);
-		__stop_umh();
-		ret = -EFAULT;
-		goto out;
+		goto stop;
 	}
-	ret = reply.status;
-out:
-	return ret;
+	return reply.status;
+stop:
+	__stop_umh();
+	return -EFAULT;
+}
+
+static int bpfilter_process_sockopt(struct sock *sk, int optname,
+				    sockptr_t optval, unsigned int optlen,
+				    bool is_set)
+{
+	struct mbox_request req = {
+		.is_set		= is_set,
+		.pid		= current->pid,
+		.cmd		= optname,
+		.addr		= (uintptr_t)optval.user,
+		.len		= optlen,
+	};
+	if (uaccess_kernel() || sockptr_is_kernel(optval)) {
+		pr_err("kernel access not supported\n");
+		return -EFAULT;
+	}
+	return bpfilter_send_req(&req);
 }
 
 static int start_umh(void)
 {
+	struct mbox_request req = { .pid = current->pid };
 	int err;
 
 	/* fork usermode process */
-	err = fork_usermode_blob(&bpfilter_umh_start,
-				 &bpfilter_umh_end - &bpfilter_umh_start,
-				 &bpfilter_ops.info);
+	err = fork_usermode_driver(&bpfilter_ops.info);
 	if (err)
 		return err;
-	bpfilter_ops.stop = false;
-	pr_info("Loaded bpfilter_umh pid %d\n", bpfilter_ops.info.pid);
+	pr_info("Loaded bpfilter_umh pid %d\n", pid_nr(bpfilter_ops.info.tgid));
 
 	/* health check that usermode process started correctly */
-	if (__bpfilter_process_sockopt(NULL, 0, NULL, 0, 0) != 0) {
+	if (bpfilter_send_req(&req) != 0) {
 		shutdown_umh();
 		return -EFAULT;
 	}
@@ -98,18 +101,21 @@ static int __init load_umh(void)
 {
 	int err;
 
+	err = umd_load_blob(&bpfilter_ops.info,
+			    &bpfilter_umh_start,
+			    &bpfilter_umh_end - &bpfilter_umh_start);
+	if (err)
+		return err;
+
 	mutex_lock(&bpfilter_ops.lock);
-	if (!bpfilter_ops.stop) {
-		err = -EFAULT;
-		goto out;
-	}
 	err = start_umh();
 	if (!err && IS_ENABLED(CONFIG_INET)) {
-		bpfilter_ops.sockopt = &__bpfilter_process_sockopt;
+		bpfilter_ops.sockopt = &bpfilter_process_sockopt;
 		bpfilter_ops.start = &start_umh;
 	}
-out:
 	mutex_unlock(&bpfilter_ops.lock);
+	if (err)
+		umd_unload_blob(&bpfilter_ops.info);
 	return err;
 }
 
@@ -122,6 +128,8 @@ static void __exit fini_umh(void)
 		bpfilter_ops.sockopt = NULL;
 	}
 	mutex_unlock(&bpfilter_ops.lock);
+
+	umd_unload_blob(&bpfilter_ops.info);
 }
 module_init(load_umh);
 module_exit(fini_umh);