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-rw-r--r--ipc/kdbus/handle.c691
1 files changed, 0 insertions, 691 deletions
diff --git a/ipc/kdbus/handle.c b/ipc/kdbus/handle.c
deleted file mode 100644
index 2f82c2a32..000000000
--- a/ipc/kdbus/handle.c
+++ /dev/null
@@ -1,691 +0,0 @@
-/*
- * Copyright (C) 2013-2015 Kay Sievers
- * Copyright (C) 2013-2015 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- * Copyright (C) 2013-2015 Daniel Mack <daniel@zonque.org>
- * Copyright (C) 2013-2015 David Herrmann <dh.herrmann@gmail.com>
- * Copyright (C) 2013-2015 Linux Foundation
- * Copyright (C) 2014-2015 Djalal Harouni <tixxdz@opendz.org>
- *
- * kdbus is free software; you can redistribute it and/or modify it under
- * the terms of the GNU Lesser General Public License as published by the
- * Free Software Foundation; either version 2.1 of the License, or (at
- * your option) any later version.
- */
-
-#include <linux/file.h>
-#include <linux/fs.h>
-#include <linux/idr.h>
-#include <linux/init.h>
-#include <linux/kdev_t.h>
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/poll.h>
-#include <linux/rwsem.h>
-#include <linux/sched.h>
-#include <linux/sizes.h>
-#include <linux/slab.h>
-#include <linux/uaccess.h>
-#include <linux/syscalls.h>
-
-#include "bus.h"
-#include "connection.h"
-#include "endpoint.h"
-#include "fs.h"
-#include "handle.h"
-#include "item.h"
-#include "match.h"
-#include "message.h"
-#include "names.h"
-#include "domain.h"
-#include "policy.h"
-
-static int kdbus_args_verify(struct kdbus_args *args)
-{
- struct kdbus_item *item;
- size_t i;
- int ret;
-
- KDBUS_ITEMS_FOREACH(item, args->items, args->items_size) {
- struct kdbus_arg *arg = NULL;
-
- if (!KDBUS_ITEM_VALID(item, args->items, args->items_size))
- return -EINVAL;
-
- for (i = 0; i < args->argc; ++i)
- if (args->argv[i].type == item->type)
- break;
- if (i >= args->argc)
- return -EINVAL;
-
- arg = &args->argv[i];
-
- ret = kdbus_item_validate(item);
- if (ret < 0)
- return ret;
-
- if (arg->item && !arg->multiple)
- return -EINVAL;
-
- arg->item = item;
- }
-
- if (!KDBUS_ITEMS_END(item, args->items, args->items_size))
- return -EINVAL;
-
- return 0;
-}
-
-static int kdbus_args_negotiate(struct kdbus_args *args)
-{
- struct kdbus_item __user *user;
- struct kdbus_item *negotiation;
- size_t i, j, num;
-
- /*
- * If KDBUS_FLAG_NEGOTIATE is set, we overwrite the flags field with
- * the set of supported flags. Furthermore, if an KDBUS_ITEM_NEGOTIATE
- * item is passed, we iterate its payload (array of u64, each set to an
- * item type) and clear all unsupported item-types to 0.
- * The caller might do this recursively, if other flags or objects are
- * embedded in the payload itself.
- */
-
- if (args->cmd->flags & KDBUS_FLAG_NEGOTIATE) {
- if (put_user(args->allowed_flags & ~KDBUS_FLAG_NEGOTIATE,
- &args->user->flags))
- return -EFAULT;
- }
-
- if (args->argc < 1 || args->argv[0].type != KDBUS_ITEM_NEGOTIATE ||
- !args->argv[0].item)
- return 0;
-
- negotiation = args->argv[0].item;
- user = (struct kdbus_item __user *)
- ((u8 __user *)args->user +
- ((u8 *)negotiation - (u8 *)args->cmd));
- num = KDBUS_ITEM_PAYLOAD_SIZE(negotiation) / sizeof(u64);
-
- for (i = 0; i < num; ++i) {
- for (j = 0; j < args->argc; ++j)
- if (negotiation->data64[i] == args->argv[j].type)
- break;
-
- if (j < args->argc)
- continue;
-
- /* this item is not supported, clear it out */
- negotiation->data64[i] = 0;
- if (put_user(negotiation->data64[i], &user->data64[i]))
- return -EFAULT;
- }
-
- return 0;
-}
-
-/**
- * __kdbus_args_parse() - parse payload of kdbus command
- * @args: object to parse data into
- * @is_cmd: whether this is a command or msg payload
- * @argp: user-space location of command payload to parse
- * @type_size: overall size of command payload to parse
- * @items_offset: offset of items array in command payload
- * @out: output variable to store pointer to copied payload
- *
- * This parses the ioctl payload at user-space location @argp into @args. @args
- * must be pre-initialized by the caller to reflect the supported flags and
- * items of this command. This parser will then copy the command payload into
- * kernel-space, verify correctness and consistency and cache pointers to parsed
- * items and other data in @args.
- *
- * If this function succeeded, you must call kdbus_args_clear() to release
- * allocated resources before destroying @args.
- *
- * This can also be used to import kdbus_msg objects. In that case, @is_cmd must
- * be set to 'false' and the 'return_flags' field will not be touched (as it
- * doesn't exist on kdbus_msg).
- *
- * Return: On failure a negative error code is returned. Otherwise, 1 is
- * returned if negotiation was requested, 0 if not.
- */
-int __kdbus_args_parse(struct kdbus_args *args, bool is_cmd, void __user *argp,
- size_t type_size, size_t items_offset, void **out)
-{
- u64 user_size;
- int ret, i;
-
- ret = kdbus_copy_from_user(&user_size, argp, sizeof(user_size));
- if (ret < 0)
- return ret;
-
- if (user_size < type_size)
- return -EINVAL;
- if (user_size > KDBUS_CMD_MAX_SIZE)
- return -EMSGSIZE;
-
- if (user_size <= sizeof(args->cmd_buf)) {
- if (copy_from_user(args->cmd_buf, argp, user_size))
- return -EFAULT;
- args->cmd = (void*)args->cmd_buf;
- } else {
- args->cmd = memdup_user(argp, user_size);
- if (IS_ERR(args->cmd))
- return PTR_ERR(args->cmd);
- }
-
- if (args->cmd->size != user_size) {
- ret = -EINVAL;
- goto error;
- }
-
- if (is_cmd)
- args->cmd->return_flags = 0;
- args->user = argp;
- args->items = (void *)((u8 *)args->cmd + items_offset);
- args->items_size = args->cmd->size - items_offset;
- args->is_cmd = is_cmd;
-
- if (args->cmd->flags & ~args->allowed_flags) {
- ret = -EINVAL;
- goto error;
- }
-
- ret = kdbus_args_verify(args);
- if (ret < 0)
- goto error;
-
- ret = kdbus_args_negotiate(args);
- if (ret < 0)
- goto error;
-
- /* mandatory items must be given (but not on negotiation) */
- if (!(args->cmd->flags & KDBUS_FLAG_NEGOTIATE)) {
- for (i = 0; i < args->argc; ++i)
- if (args->argv[i].mandatory && !args->argv[i].item) {
- ret = -EINVAL;
- goto error;
- }
- }
-
- *out = args->cmd;
- return !!(args->cmd->flags & KDBUS_FLAG_NEGOTIATE);
-
-error:
- return kdbus_args_clear(args, ret);
-}
-
-/**
- * kdbus_args_clear() - release allocated command resources
- * @args: object to release resources of
- * @ret: return value of this command
- *
- * This frees all allocated resources on @args and copies the command result
- * flags into user-space. @ret is usually returned unchanged by this function,
- * so it can be used in the final 'return' statement of the command handler.
- *
- * Return: -EFAULT if return values cannot be copied into user-space, otherwise
- * @ret is returned unchanged.
- */
-int kdbus_args_clear(struct kdbus_args *args, int ret)
-{
- if (!args)
- return ret;
-
- if (!IS_ERR_OR_NULL(args->cmd)) {
- if (args->is_cmd && put_user(args->cmd->return_flags,
- &args->user->return_flags))
- ret = -EFAULT;
- if (args->cmd != (void*)args->cmd_buf)
- kfree(args->cmd);
- args->cmd = NULL;
- }
-
- return ret;
-}
-
-/**
- * enum kdbus_handle_type - type an handle can be of
- * @KDBUS_HANDLE_NONE: no type set, yet
- * @KDBUS_HANDLE_BUS_OWNER: bus owner
- * @KDBUS_HANDLE_EP_OWNER: endpoint owner
- * @KDBUS_HANDLE_CONNECTED: endpoint connection after HELLO
- */
-enum kdbus_handle_type {
- KDBUS_HANDLE_NONE,
- KDBUS_HANDLE_BUS_OWNER,
- KDBUS_HANDLE_EP_OWNER,
- KDBUS_HANDLE_CONNECTED,
-};
-
-/**
- * struct kdbus_handle - handle to the kdbus system
- * @lock: handle lock
- * @type: type of this handle (KDBUS_HANDLE_*)
- * @bus_owner: bus this handle owns
- * @ep_owner: endpoint this handle owns
- * @conn: connection this handle owns
- */
-struct kdbus_handle {
- struct mutex lock;
-
- enum kdbus_handle_type type;
- union {
- struct kdbus_bus *bus_owner;
- struct kdbus_ep *ep_owner;
- struct kdbus_conn *conn;
- };
-};
-
-static int kdbus_handle_open(struct inode *inode, struct file *file)
-{
- struct kdbus_handle *handle;
- struct kdbus_node *node;
- int ret;
-
- node = kdbus_node_from_inode(inode);
- if (!kdbus_node_acquire(node))
- return -ESHUTDOWN;
-
- handle = kzalloc(sizeof(*handle), GFP_KERNEL);
- if (!handle) {
- ret = -ENOMEM;
- goto exit;
- }
-
- mutex_init(&handle->lock);
- handle->type = KDBUS_HANDLE_NONE;
-
- file->private_data = handle;
- ret = 0;
-
-exit:
- kdbus_node_release(node);
- return ret;
-}
-
-static int kdbus_handle_release(struct inode *inode, struct file *file)
-{
- struct kdbus_handle *handle = file->private_data;
-
- switch (handle->type) {
- case KDBUS_HANDLE_BUS_OWNER:
- if (handle->bus_owner) {
- kdbus_node_drain(&handle->bus_owner->node);
- kdbus_bus_unref(handle->bus_owner);
- }
- break;
- case KDBUS_HANDLE_EP_OWNER:
- if (handle->ep_owner) {
- kdbus_node_drain(&handle->ep_owner->node);
- kdbus_ep_unref(handle->ep_owner);
- }
- break;
- case KDBUS_HANDLE_CONNECTED:
- kdbus_conn_disconnect(handle->conn, false);
- kdbus_conn_unref(handle->conn);
- break;
- case KDBUS_HANDLE_NONE:
- /* nothing to clean up */
- break;
- }
-
- kfree(handle);
-
- return 0;
-}
-
-static long kdbus_handle_ioctl_control(struct file *file, unsigned int cmd,
- void __user *argp)
-{
- struct kdbus_handle *handle = file->private_data;
- struct kdbus_node *node = file_inode(file)->i_private;
- struct kdbus_domain *domain;
- int ret = 0;
-
- if (!kdbus_node_acquire(node))
- return -ESHUTDOWN;
-
- /*
- * The parent of control-nodes is always a domain, make sure to pin it
- * so the parent is actually valid.
- */
- domain = kdbus_domain_from_node(node->parent);
- if (!kdbus_node_acquire(&domain->node)) {
- kdbus_node_release(node);
- return -ESHUTDOWN;
- }
-
- switch (cmd) {
- case KDBUS_CMD_BUS_MAKE: {
- struct kdbus_bus *bus;
-
- bus = kdbus_cmd_bus_make(domain, argp);
- if (IS_ERR_OR_NULL(bus)) {
- ret = PTR_ERR_OR_ZERO(bus);
- break;
- }
-
- handle->bus_owner = bus;
- ret = KDBUS_HANDLE_BUS_OWNER;
- break;
- }
-
- default:
- ret = -EBADFD;
- break;
- }
-
- kdbus_node_release(&domain->node);
- kdbus_node_release(node);
- return ret;
-}
-
-static long kdbus_handle_ioctl_ep(struct file *file, unsigned int cmd,
- void __user *buf)
-{
- struct kdbus_handle *handle = file->private_data;
- struct kdbus_node *node = file_inode(file)->i_private;
- struct kdbus_ep *ep, *file_ep = kdbus_ep_from_node(node);
- struct kdbus_bus *bus = file_ep->bus;
- struct kdbus_conn *conn;
- int ret = 0;
-
- if (!kdbus_node_acquire(node))
- return -ESHUTDOWN;
-
- switch (cmd) {
- case KDBUS_CMD_ENDPOINT_MAKE: {
- /* creating custom endpoints is a privileged operation */
- if (!kdbus_ep_is_owner(file_ep, file)) {
- ret = -EPERM;
- break;
- }
-
- ep = kdbus_cmd_ep_make(bus, buf);
- if (IS_ERR_OR_NULL(ep)) {
- ret = PTR_ERR_OR_ZERO(ep);
- break;
- }
-
- handle->ep_owner = ep;
- ret = KDBUS_HANDLE_EP_OWNER;
- break;
- }
-
- case KDBUS_CMD_HELLO:
- conn = kdbus_cmd_hello(file_ep, file, buf);
- if (IS_ERR_OR_NULL(conn)) {
- ret = PTR_ERR_OR_ZERO(conn);
- break;
- }
-
- handle->conn = conn;
- ret = KDBUS_HANDLE_CONNECTED;
- break;
-
- default:
- ret = -EBADFD;
- break;
- }
-
- kdbus_node_release(node);
- return ret;
-}
-
-static long kdbus_handle_ioctl_ep_owner(struct file *file, unsigned int command,
- void __user *buf)
-{
- struct kdbus_handle *handle = file->private_data;
- struct kdbus_ep *ep = handle->ep_owner;
- int ret;
-
- if (!kdbus_node_acquire(&ep->node))
- return -ESHUTDOWN;
-
- switch (command) {
- case KDBUS_CMD_ENDPOINT_UPDATE:
- ret = kdbus_cmd_ep_update(ep, buf);
- break;
- default:
- ret = -EBADFD;
- break;
- }
-
- kdbus_node_release(&ep->node);
- return ret;
-}
-
-static long kdbus_handle_ioctl_connected(struct file *file,
- unsigned int command, void __user *buf)
-{
- struct kdbus_handle *handle = file->private_data;
- struct kdbus_conn *conn = handle->conn;
- struct kdbus_conn *release_conn = NULL;
- int ret;
-
- release_conn = conn;
- ret = kdbus_conn_acquire(release_conn);
- if (ret < 0)
- return ret;
-
- switch (command) {
- case KDBUS_CMD_BYEBYE:
- /*
- * BYEBYE is special; we must not acquire a connection when
- * calling into kdbus_conn_disconnect() or we will deadlock,
- * because kdbus_conn_disconnect() will wait for all acquired
- * references to be dropped.
- */
- kdbus_conn_release(release_conn);
- release_conn = NULL;
- ret = kdbus_cmd_byebye_unlocked(conn, buf);
- break;
- case KDBUS_CMD_NAME_ACQUIRE:
- ret = kdbus_cmd_name_acquire(conn, buf);
- break;
- case KDBUS_CMD_NAME_RELEASE:
- ret = kdbus_cmd_name_release(conn, buf);
- break;
- case KDBUS_CMD_LIST:
- ret = kdbus_cmd_list(conn, buf);
- break;
- case KDBUS_CMD_CONN_INFO:
- ret = kdbus_cmd_conn_info(conn, buf);
- break;
- case KDBUS_CMD_BUS_CREATOR_INFO:
- ret = kdbus_cmd_bus_creator_info(conn, buf);
- break;
- case KDBUS_CMD_UPDATE:
- ret = kdbus_cmd_update(conn, buf);
- break;
- case KDBUS_CMD_MATCH_ADD:
- ret = kdbus_cmd_match_add(conn, buf);
- break;
- case KDBUS_CMD_MATCH_REMOVE:
- ret = kdbus_cmd_match_remove(conn, buf);
- break;
- case KDBUS_CMD_SEND:
- ret = kdbus_cmd_send(conn, file, buf);
- break;
- case KDBUS_CMD_RECV:
- ret = kdbus_cmd_recv(conn, buf);
- break;
- case KDBUS_CMD_FREE:
- ret = kdbus_cmd_free(conn, buf);
- break;
- default:
- ret = -EBADFD;
- break;
- }
-
- kdbus_conn_release(release_conn);
- return ret;
-}
-
-static long kdbus_handle_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- struct kdbus_handle *handle = file->private_data;
- struct kdbus_node *node = kdbus_node_from_inode(file_inode(file));
- void __user *argp = (void __user *)arg;
- long ret = -EBADFD;
-
- switch (cmd) {
- case KDBUS_CMD_BUS_MAKE:
- case KDBUS_CMD_ENDPOINT_MAKE:
- case KDBUS_CMD_HELLO:
- mutex_lock(&handle->lock);
- if (handle->type == KDBUS_HANDLE_NONE) {
- if (node->type == KDBUS_NODE_CONTROL)
- ret = kdbus_handle_ioctl_control(file, cmd,
- argp);
- else if (node->type == KDBUS_NODE_ENDPOINT)
- ret = kdbus_handle_ioctl_ep(file, cmd, argp);
-
- if (ret > 0) {
- /*
- * The data given via open() is not sufficient
- * to setup a kdbus handle. Hence, we require
- * the user to perform a setup ioctl. This setup
- * can only be performed once and defines the
- * type of the handle. The different setup
- * ioctls are locked against each other so they
- * cannot race. Once the handle type is set,
- * the type-dependent ioctls are enabled. To
- * improve performance, we don't lock those via
- * handle->lock. Instead, we issue a
- * write-barrier before performing the
- * type-change, which pairs with smp_rmb() in
- * all handlers that access the type field. This
- * guarantees the handle is fully setup, if
- * handle->type is set. If handle->type is
- * unset, you must not make any assumptions
- * without taking handle->lock.
- * Note that handle->type is only set once. It
- * will never change afterwards.
- */
- smp_wmb();
- handle->type = ret;
- }
- }
- mutex_unlock(&handle->lock);
- break;
-
- case KDBUS_CMD_ENDPOINT_UPDATE:
- case KDBUS_CMD_BYEBYE:
- case KDBUS_CMD_NAME_ACQUIRE:
- case KDBUS_CMD_NAME_RELEASE:
- case KDBUS_CMD_LIST:
- case KDBUS_CMD_CONN_INFO:
- case KDBUS_CMD_BUS_CREATOR_INFO:
- case KDBUS_CMD_UPDATE:
- case KDBUS_CMD_MATCH_ADD:
- case KDBUS_CMD_MATCH_REMOVE:
- case KDBUS_CMD_SEND:
- case KDBUS_CMD_RECV:
- case KDBUS_CMD_FREE: {
- enum kdbus_handle_type type;
-
- /*
- * This read-barrier pairs with smp_wmb() of the handle setup.
- * it guarantees the handle is fully written, in case the
- * type has been set. It allows us to access the handle without
- * taking handle->lock, given the guarantee that the type is
- * only ever set once, and stays constant afterwards.
- * Furthermore, the handle object itself is not modified in any
- * way after the type is set. That is, the type-field is the
- * last field that is written on any handle. If it has not been
- * set, we must not access the handle here.
- */
- type = handle->type;
- smp_rmb();
-
- if (type == KDBUS_HANDLE_EP_OWNER)
- ret = kdbus_handle_ioctl_ep_owner(file, cmd, argp);
- else if (type == KDBUS_HANDLE_CONNECTED)
- ret = kdbus_handle_ioctl_connected(file, cmd, argp);
-
- break;
- }
- default:
- ret = -ENOTTY;
- break;
- }
-
- return ret < 0 ? ret : 0;
-}
-
-static unsigned int kdbus_handle_poll(struct file *file,
- struct poll_table_struct *wait)
-{
- struct kdbus_handle *handle = file->private_data;
- enum kdbus_handle_type type;
- unsigned int mask = POLLOUT | POLLWRNORM;
-
- /*
- * This pairs with smp_wmb() during handle setup. It guarantees that
- * _iff_ the handle type is set, handle->conn is valid. Furthermore,
- * _iff_ the type is set, the handle object is constant and never
- * changed again. If it's not set, we must not access the handle but
- * bail out. We also must assume no setup has taken place, yet.
- */
- type = handle->type;
- smp_rmb();
-
- /* Only a connected endpoint can read/write data */
- if (type != KDBUS_HANDLE_CONNECTED)
- return POLLERR | POLLHUP;
-
- poll_wait(file, &handle->conn->wait, wait);
-
- /*
- * Verify the connection hasn't been deactivated _after_ adding the
- * wait-queue. This guarantees, that if the connection is deactivated
- * after we checked it, the waitqueue is signaled and we're called
- * again.
- */
- if (!kdbus_conn_active(handle->conn))
- return POLLERR | POLLHUP;
-
- if (!list_empty(&handle->conn->queue.msg_list) ||
- atomic_read(&handle->conn->lost_count) > 0)
- mask |= POLLIN | POLLRDNORM;
-
- return mask;
-}
-
-static int kdbus_handle_mmap(struct file *file, struct vm_area_struct *vma)
-{
- struct kdbus_handle *handle = file->private_data;
- enum kdbus_handle_type type;
- int ret = -EBADFD;
-
- /*
- * This pairs with smp_wmb() during handle setup. It guarantees that
- * _iff_ the handle type is set, handle->conn is valid. Furthermore,
- * _iff_ the type is set, the handle object is constant and never
- * changed again. If it's not set, we must not access the handle but
- * bail out. We also must assume no setup has taken place, yet.
- */
- type = handle->type;
- smp_rmb();
-
- /* Only connected handles have a pool we can map */
- if (type == KDBUS_HANDLE_CONNECTED)
- ret = kdbus_pool_mmap(handle->conn->pool, vma);
-
- return ret;
-}
-
-const struct file_operations kdbus_handle_ops = {
- .owner = THIS_MODULE,
- .open = kdbus_handle_open,
- .release = kdbus_handle_release,
- .poll = kdbus_handle_poll,
- .llseek = noop_llseek,
- .unlocked_ioctl = kdbus_handle_ioctl,
- .mmap = kdbus_handle_mmap,
-#ifdef CONFIG_COMPAT
- .compat_ioctl = kdbus_handle_ioctl,
-#endif
-};
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