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-rw-r--r--Documentation/ioctl/ioctl-number.txt1
-rw-r--r--ipc/kdbus/handle.c617
-rw-r--r--ipc/kdbus/handle.h85
-rw-r--r--ipc/kdbus/limits.h64
-rw-r--r--ipc/kdbus/main.c125
-rw-r--r--ipc/kdbus/util.c201
-rw-r--r--ipc/kdbus/util.h74
7 files changed, 1167 insertions, 0 deletions
diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt
index 51f4221657bf..ec7c81b4f941 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -292,6 +292,7 @@ Code Seq#(hex) Include File Comments
0x92 00-0F drivers/usb/mon/mon_bin.c
0x93 60-7F linux/auto_fs.h
0x94 all fs/btrfs/ioctl.h
+0x95 all uapi/linux/kdbus.h kdbus IPC driver
0x97 00-7F fs/ceph/ioctl.h Ceph file system
0x99 00-0F 537-Addinboard driver
<mailto:buk@buks.ipn.de>
diff --git a/ipc/kdbus/handle.c b/ipc/kdbus/handle.c
new file mode 100644
index 000000000000..f72dbe513b4a
--- /dev/null
+++ b/ipc/kdbus/handle.c
@@ -0,0 +1,617 @@
+/*
+ * 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/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;
+
+ for (i = 0; i < args->argc; ++i)
+ if (args->argv[i].mandatory && !args->argv[i].item)
+ 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
+ * @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.
+ *
+ * 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, void __user *argp,
+ size_t type_size, size_t items_offset, void **out)
+{
+ int ret;
+
+ args->cmd = kdbus_memdup_user(argp, type_size, KDBUS_CMD_MAX_SIZE);
+ if (IS_ERR(args->cmd))
+ return PTR_ERR(args->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;
+
+ 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;
+
+ *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 (put_user(args->cmd->return_flags,
+ &args->user->return_flags))
+ ret = -EFAULT;
+ 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
+ * @rwlock: 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
+ * @privileged: Flag to mark a handle as privileged
+ */
+struct kdbus_handle {
+ struct rw_semaphore rwlock;
+
+ enum kdbus_handle_type type;
+ union {
+ struct kdbus_bus *bus_owner;
+ struct kdbus_ep *ep_owner;
+ struct kdbus_conn *conn;
+ };
+
+ bool privileged:1;
+};
+
+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;
+ }
+
+ init_rwsem(&handle->rwlock);
+ handle->type = KDBUS_HANDLE_NONE;
+
+ if (node->type == KDBUS_NODE_ENDPOINT) {
+ struct kdbus_ep *ep = kdbus_ep_from_node(node);
+ struct kdbus_bus *bus = ep->bus;
+
+ /*
+ * A connection is privileged if it is opened on an endpoint
+ * without custom policy and either:
+ * * the user has CAP_IPC_OWNER in the domain user namespace
+ * or
+ * * the callers euid matches the uid of the bus creator
+ */
+ if (!ep->user &&
+ (ns_capable(bus->domain->user_namespace, CAP_IPC_OWNER) ||
+ uid_eq(file->f_cred->euid, bus->node.uid)))
+ handle->privileged = true;
+ }
+
+ 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_deactivate(&handle->bus_owner->node);
+ kdbus_bus_unref(handle->bus_owner);
+ }
+ break;
+ case KDBUS_HANDLE_EP_OWNER:
+ if (handle->ep_owner) {
+ kdbus_node_deactivate(&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->type = KDBUS_HANDLE_BUS_OWNER;
+ handle->bus_owner = bus;
+ 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_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 (!handle->privileged) {
+ ret = -EPERM;
+ break;
+ }
+
+ ep = kdbus_cmd_ep_make(file_ep->bus, buf);
+ if (IS_ERR_OR_NULL(ep)) {
+ ret = PTR_ERR_OR_ZERO(ep);
+ break;
+ }
+
+ handle->type = KDBUS_HANDLE_EP_OWNER;
+ handle->ep_owner = ep;
+ break;
+
+ case KDBUS_CMD_HELLO:
+ conn = kdbus_cmd_hello(file_ep, handle->privileged, buf);
+ if (IS_ERR_OR_NULL(conn)) {
+ ret = PTR_ERR_OR_ZERO(conn);
+ break;
+ }
+
+ handle->type = KDBUS_HANDLE_CONNECTED;
+ handle->conn = conn;
+ 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:
+ /* bail out early if already typed */
+ if (handle->type != KDBUS_HANDLE_NONE)
+ break;
+
+ down_write(&handle->rwlock);
+ 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);
+ }
+ up_write(&handle->rwlock);
+ 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:
+ down_read(&handle->rwlock);
+ if (handle->type == KDBUS_HANDLE_EP_OWNER)
+ ret = kdbus_handle_ioctl_ep_owner(file, cmd, argp);
+ else if (handle->type == KDBUS_HANDLE_CONNECTED)
+ ret = kdbus_handle_ioctl_connected(file, cmd, argp);
+ up_read(&handle->rwlock);
+ 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;
+ unsigned int mask = POLLOUT | POLLWRNORM;
+ int ret;
+
+ /* Only a connected endpoint can read/write data */
+ down_read(&handle->rwlock);
+ if (handle->type != KDBUS_HANDLE_CONNECTED) {
+ up_read(&handle->rwlock);
+ return POLLERR | POLLHUP;
+ }
+ up_read(&handle->rwlock);
+
+ ret = kdbus_conn_acquire(handle->conn);
+ if (ret < 0)
+ return POLLERR | POLLHUP;
+
+ poll_wait(file, &handle->conn->wait, wait);
+
+ if (!list_empty(&handle->conn->queue.msg_list) ||
+ atomic_read(&handle->conn->lost_count) > 0)
+ mask |= POLLIN | POLLRDNORM;
+
+ kdbus_conn_release(handle->conn);
+
+ return mask;
+}
+
+static int kdbus_handle_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct kdbus_handle *handle = file->private_data;
+ int ret = -EBADFD;
+
+ if (down_read_trylock(&handle->rwlock)) {
+ if (handle->type == KDBUS_HANDLE_CONNECTED)
+ ret = kdbus_pool_mmap(handle->conn->pool, vma);
+ up_read(&handle->rwlock);
+ }
+ 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
+};
diff --git a/ipc/kdbus/handle.h b/ipc/kdbus/handle.h
new file mode 100644
index 000000000000..93a372d554a2
--- /dev/null
+++ b/ipc/kdbus/handle.h
@@ -0,0 +1,85 @@
+/*
+ * 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
+ *
+ * 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.
+ */
+
+#ifndef __KDBUS_HANDLE_H
+#define __KDBUS_HANDLE_H
+
+#include <linux/fs.h>
+#include <uapi/linux/kdbus.h>
+
+extern const struct file_operations kdbus_handle_ops;
+
+/**
+ * kdbus_arg - information and state of a single ioctl command item
+ * @type: item type
+ * @item: set by the parser to the first found item of this type
+ * @multiple: whether multiple items of this type are allowed
+ * @mandatory: whether at least one item of this type is required
+ *
+ * This structure describes a single item in an ioctl command payload. The
+ * caller has to pre-fill the type and flags, the parser will then use this
+ * information to verify the ioctl payload. @item is set by the parser to point
+ * to the first occurrence of the item.
+ */
+struct kdbus_arg {
+ u64 type;
+ struct kdbus_item *item;
+ bool multiple : 1;
+ bool mandatory : 1;
+};
+
+/**
+ * kdbus_args - information and state of ioctl command parser
+ * @allowed_flags: set of flags this command supports
+ * @argc: number of items in @argv
+ * @argv: array of items this command supports
+ * @user: set by parser to user-space location of current command
+ * @cmd: set by parser to kernel copy of command payload
+ * @items: points to item array in @cmd
+ * @items_size: size of @items in bytes
+ *
+ * This structure is used to parse ioctl command payloads on each invocation.
+ * The ioctl handler has to pre-fill the flags and allowed items before passing
+ * the object to kdbus_args_parse(). The parser will copy the command payload
+ * into kernel-space and verify the correctness of the data.
+ */
+struct kdbus_args {
+ u64 allowed_flags;
+ size_t argc;
+ struct kdbus_arg *argv;
+
+ struct kdbus_cmd __user *user;
+ struct kdbus_cmd *cmd;
+
+ struct kdbus_item *items;
+ size_t items_size;
+};
+
+int __kdbus_args_parse(struct kdbus_args *args, void __user *argp,
+ size_t type_size, size_t items_offset, void **out);
+int kdbus_args_clear(struct kdbus_args *args, int ret);
+
+#define kdbus_args_parse(_args, _argp, _v) \
+ ({ \
+ BUILD_BUG_ON(offsetof(typeof(**(_v)), size) != \
+ offsetof(struct kdbus_cmd, size)); \
+ BUILD_BUG_ON(offsetof(typeof(**(_v)), flags) != \
+ offsetof(struct kdbus_cmd, flags)); \
+ BUILD_BUG_ON(offsetof(typeof(**(_v)), return_flags) != \
+ offsetof(struct kdbus_cmd, return_flags)); \
+ __kdbus_args_parse((_args), (_argp), sizeof(**(_v)), \
+ offsetof(typeof(**(_v)), items), \
+ (void **)(_v)); \
+ })
+
+#endif
diff --git a/ipc/kdbus/limits.h b/ipc/kdbus/limits.h
new file mode 100644
index 000000000000..6450f58cffcf
--- /dev/null
+++ b/ipc/kdbus/limits.h
@@ -0,0 +1,64 @@
+/*
+ * 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
+ *
+ * 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.
+ */
+
+#ifndef __KDBUS_DEFAULTS_H
+#define __KDBUS_DEFAULTS_H
+
+#include <linux/kernel.h>
+
+/* maximum size of message header and items */
+#define KDBUS_MSG_MAX_SIZE SZ_8K
+
+/* maximum number of message items */
+#define KDBUS_MSG_MAX_ITEMS 128
+
+/* maximum number of memfd items per message */
+#define KDBUS_MSG_MAX_MEMFD_ITEMS 16
+
+/* max size of ioctl command data */
+#define KDBUS_CMD_MAX_SIZE SZ_32K
+
+/* maximum number of inflight fds in a target queue per user */
+#define KDBUS_CONN_MAX_FDS_PER_USER 16
+
+/* maximum message payload size */
+#define KDBUS_MSG_MAX_PAYLOAD_VEC_SIZE SZ_2M
+
+/* maximum size of bloom bit field in bytes */
+#define KDBUS_BUS_BLOOM_MAX_SIZE SZ_4K
+
+/* maximum length of well-known bus name */
+#define KDBUS_NAME_MAX_LEN 255
+
+/* maximum length of bus, domain, ep name */
+#define KDBUS_SYSNAME_MAX_LEN 63
+
+/* maximum number of matches per connection */
+#define KDBUS_MATCH_MAX 256
+
+/* maximum number of queued messages from the same individual user */
+#define KDBUS_CONN_MAX_MSGS 256
+
+/* maximum number of well-known names per connection */
+#define KDBUS_CONN_MAX_NAMES 256
+
+/* maximum number of queued requests waiting for a reply */
+#define KDBUS_CONN_MAX_REQUESTS_PENDING 128
+
+/* maximum number of connections per user in one domain */
+#define KDBUS_USER_MAX_CONN 1024
+
+/* maximum number of buses per user in one domain */
+#define KDBUS_USER_MAX_BUSES 16
+
+#endif
diff --git a/ipc/kdbus/main.c b/ipc/kdbus/main.c
new file mode 100644
index 000000000000..785f529d98b7
--- /dev/null
+++ b/ipc/kdbus/main.c
@@ -0,0 +1,125 @@
+/*
+ * 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
+ *
+ * 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+
+#include "util.h"
+#include "fs.h"
+#include "handle.h"
+#include "metadata.h"
+#include "node.h"
+
+/*
+ * This is a simplified outline of the internal kdbus object relations, for
+ * those interested in the inner life of the driver implementation.
+ *
+ * From a mount point's (domain's) perspective:
+ *
+ * struct kdbus_domain
+ * |» struct kdbus_user *user (many, owned)
+ * '» struct kdbus_node node (embedded)
+ * |» struct kdbus_node children (many, referenced)
+ * |» struct kdbus_node *parent (pinned)
+ * '» struct kdbus_bus (many, pinned)
+ * |» struct kdbus_node node (embedded)
+ * '» struct kdbus_ep (many, pinned)
+ * |» struct kdbus_node node (embedded)
+ * |» struct kdbus_bus *bus (pinned)
+ * |» struct kdbus_conn conn_list (many, pinned)
+ * | |» struct kdbus_ep *ep (pinned)
+ * | |» struct kdbus_name_entry *activator_of (owned)
+ * | |» struct kdbus_match_db *match_db (owned)
+ * | |» struct kdbus_meta *meta (owned)
+ * | |» struct kdbus_match_db *match_db (owned)
+ * | | '» struct kdbus_match_entry (many, owned)
+ * | |
+ * | |» struct kdbus_pool *pool (owned)
+ * | | '» struct kdbus_pool_slice *slices (many, owned)
+ * | | '» struct kdbus_pool *pool (pinned)
+ * | |
+ * | |» struct kdbus_user *user (pinned)
+ * | `» struct kdbus_queue_entry entries (many, embedded)
+ * | |» struct kdbus_pool_slice *slice (pinned)
+ * | |» struct kdbus_conn_reply *reply (owned)
+ * | '» struct kdbus_user *user (pinned)
+ * |
+ * '» struct kdbus_user *user (pinned)
+ * '» struct kdbus_policy_db policy_db (embedded)
+ * |» struct kdbus_policy_db_entry (many, owned)
+ * | |» struct kdbus_conn (pinned)
+ * | '» struct kdbus_ep (pinned)
+ * |
+ * '» struct kdbus_policy_db_cache_entry (many, owned)
+ * '» struct kdbus_conn (pinned)
+ *
+ * For the life-time of a file descriptor derived from calling open() on a file
+ * inside the mount point:
+ *
+ * struct kdbus_handle
+ * |» struct kdbus_meta *meta (owned)
+ * |» struct kdbus_ep *ep (pinned)
+ * |» struct kdbus_conn *conn (owned)
+ * '» struct kdbus_ep *ep (owned)
+ */
+
+/* kdbus mount-point /sys/fs/kdbus */
+static struct kobject *kdbus_dir;
+
+/* global module option to apply a mask to exported metadata */
+unsigned long long kdbus_meta_attach_mask = KDBUS_ATTACH_TIMESTAMP |
+ KDBUS_ATTACH_CREDS |
+ KDBUS_ATTACH_PIDS |
+ KDBUS_ATTACH_AUXGROUPS |
+ KDBUS_ATTACH_NAMES |
+ KDBUS_ATTACH_SECLABEL |
+ KDBUS_ATTACH_CONN_DESCRIPTION;
+MODULE_PARM_DESC(attach_flags_mask, "Attach-flags mask for exported metadata");
+module_param_named(attach_flags_mask, kdbus_meta_attach_mask, ullong, 0644);
+
+static int __init kdbus_init(void)
+{
+ int ret;
+
+ kdbus_dir = kobject_create_and_add(KBUILD_MODNAME, fs_kobj);
+ if (!kdbus_dir)
+ return -ENOMEM;
+
+ ret = kdbus_fs_init();
+ if (ret < 0) {
+ pr_err("cannot register filesystem: %d\n", ret);
+ goto exit_dir;
+ }
+
+ pr_info("initialized\n");
+ return 0;
+
+exit_dir:
+ kobject_put(kdbus_dir);
+ return ret;
+}
+
+static void __exit kdbus_exit(void)
+{
+ kdbus_fs_exit();
+ kobject_put(kdbus_dir);
+}
+
+module_init(kdbus_init);
+module_exit(kdbus_exit);
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("D-Bus, powerful, easy to use interprocess communication");
+MODULE_ALIAS_FS(KBUILD_MODNAME "fs");
diff --git a/ipc/kdbus/util.c b/ipc/kdbus/util.c
new file mode 100644
index 000000000000..eaa806a27997
--- /dev/null
+++ b/ipc/kdbus/util.c
@@ -0,0 +1,201 @@
+/*
+ * 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/capability.h>
+#include <linux/cred.h>
+#include <linux/ctype.h>
+#include <linux/err.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <linux/uio.h>
+#include <linux/user_namespace.h>
+
+#include "limits.h"
+#include "util.h"
+
+/**
+ * kdbus_copy_from_user() - copy aligned data from user-space
+ * @dest: target buffer in kernel memory
+ * @user_ptr: user-provided source buffer
+ * @size: memory size to copy from user
+ *
+ * This copies @size bytes from @user_ptr into the kernel, just like
+ * copy_from_user() does. But we enforce an 8-byte alignment and reject any
+ * unaligned user-space pointers.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int kdbus_copy_from_user(void *dest, void __user *user_ptr, size_t size)
+{
+ if (!KDBUS_IS_ALIGNED8((uintptr_t)user_ptr))
+ return -EFAULT;
+
+ if (copy_from_user(dest, user_ptr, size))
+ return -EFAULT;
+
+ return 0;
+}
+
+/**
+ * kdbus_memdup_user() - copy dynamically sized object from user-space
+ * @user_ptr: user-provided source buffer
+ * @sz_min: minimum object size
+ * @sz_max: maximum object size
+ *
+ * This copies a dynamically sized object from user-space into kernel-space. We
+ * require the object to have a 64bit size field at offset 0. We read it out
+ * first, allocate a suitably sized buffer and then copy all data.
+ *
+ * The @sz_min and @sz_max parameters define possible min and max object sizes
+ * so user-space cannot trigger un-bound kernel-space allocations.
+ *
+ * The same alignment-restrictions as described in kdbus_copy_from_user() apply.
+ *
+ * Return: pointer to dynamically allocated copy, or ERR_PTR() on failure.
+ */
+void *kdbus_memdup_user(void __user *user_ptr, size_t sz_min, size_t sz_max)
+{
+ void *ptr;
+ u64 size;
+ int ret;
+
+ ret = kdbus_copy_from_user(&size, user_ptr, sizeof(size));
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ if (size < sz_min)
+ return ERR_PTR(-EINVAL);
+
+ if (size > sz_max)
+ return ERR_PTR(-EMSGSIZE);
+
+ ptr = memdup_user(user_ptr, size);
+ if (IS_ERR(ptr))
+ return ptr;
+
+ if (*(u64 *)ptr != size) {
+ kfree(ptr);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return ptr;
+}
+
+/**
+ * kdbus_verify_uid_prefix() - verify UID prefix of a user-supplied name
+ * @name: user-supplied name to verify
+ * @user_ns: user-namespace to act in
+ * @kuid: Kernel internal uid of user
+ *
+ * This verifies that the user-supplied name @name has their UID as prefix. This
+ * is the default name-spacing policy we enforce on user-supplied names for
+ * public kdbus entities like buses and endpoints.
+ *
+ * The user must supply names prefixed with "<UID>-", whereas the UID is
+ * interpreted in the user-namespace of the domain. If the user fails to supply
+ * such a prefixed name, we reject it.
+ *
+ * Return: 0 on success, negative error code on failure
+ */
+int kdbus_verify_uid_prefix(const char *name, struct user_namespace *user_ns,
+ kuid_t kuid)
+{
+ uid_t uid;
+ char prefix[16];
+
+ /*
+ * The kuid must have a mapping into the userns of the domain
+ * otherwise do not allow creation of buses nor endpoints.
+ */
+ uid = from_kuid(user_ns, kuid);
+ if (uid == (uid_t) -1)
+ return -EINVAL;
+
+ snprintf(prefix, sizeof(prefix), "%u-", uid);
+ if (strncmp(name, prefix, strlen(prefix)) != 0)
+ return -EINVAL;
+
+ return 0;
+}
+
+/**
+ * kdbus_sanitize_attach_flags() - Sanitize attach flags from user-space
+ * @flags: Attach flags provided by userspace
+ * @attach_flags: A pointer where to store the valid attach flags
+ *
+ * Convert attach-flags provided by user-space into a valid mask. If the mask
+ * is invalid, an error is returned. The sanitized attach flags are stored in
+ * the output parameter.
+ *
+ * Return: 0 on success, negative error on failure.
+ */
+int kdbus_sanitize_attach_flags(u64 flags, u64 *attach_flags)
+{
+ /* 'any' degrades to 'all' for compatibility */
+ if (flags == _KDBUS_ATTACH_ANY)
+ flags = _KDBUS_ATTACH_ALL;
+
+ /* reject unknown attach flags */
+ if (flags & ~_KDBUS_ATTACH_ALL)
+ return -EINVAL;
+
+ *attach_flags = flags;
+ return 0;
+}
+
+/**
+ * kdbus_kvec_set - helper utility to assemble kvec arrays
+ * @kvec: kvec entry to use
+ * @src: Source address to set in @kvec
+ * @len: Number of bytes in @src
+ * @total_len: Pointer to total length variable
+ *
+ * Set @src and @len in @kvec, and increase @total_len by @len.
+ */
+void kdbus_kvec_set(struct kvec *kvec, void *src, size_t len, u64 *total_len)
+{
+ kvec->iov_base = src;
+ kvec->iov_len = len;
+ *total_len += len;
+}
+
+static const char * const zeros = "\0\0\0\0\0\0\0";
+
+/**
+ * kdbus_kvec_pad - conditionally write a padding kvec
+ * @kvec: kvec entry to use
+ * @len: Total length used for kvec array
+ *
+ * Check if the current total byte length of the array in @len is aligned to
+ * 8 bytes. If it isn't, fill @kvec with padding information and increase @len
+ * by the number of bytes stored in @kvec.
+ *
+ * Return: the number of added padding bytes.
+ */
+size_t kdbus_kvec_pad(struct kvec *kvec, u64 *len)
+{
+ size_t pad = KDBUS_ALIGN8(*len) - *len;
+
+ if (!pad)
+ return 0;
+
+ kvec->iov_base = (void *)zeros;
+ kvec->iov_len = pad;
+
+ *len += pad;
+
+ return pad;
+}
diff --git a/ipc/kdbus/util.h b/ipc/kdbus/util.h
new file mode 100644
index 000000000000..9caadb337912
--- /dev/null
+++ b/ipc/kdbus/util.h
@@ -0,0 +1,74 @@
+/*
+ * 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.
+ */
+
+#ifndef __KDBUS_UTIL_H
+#define __KDBUS_UTIL_H
+
+#include <linux/dcache.h>
+#include <linux/ioctl.h>
+
+#include "kdbus.h"
+
+/* all exported addresses are 64 bit */
+#define KDBUS_PTR(addr) ((void __user *)(uintptr_t)(addr))
+
+/* all exported sizes are 64 bit and data aligned to 64 bit */
+#define KDBUS_ALIGN8(s) ALIGN((s), 8)
+#define KDBUS_IS_ALIGNED8(s) (IS_ALIGNED(s, 8))
+
+/**
+ * kdbus_member_set_user - write a structure member to user memory
+ * @_s: Variable to copy from
+ * @_b: Buffer to write to
+ * @_t: Structure type
+ * @_m: Member name in the passed structure
+ *
+ * Return: the result of copy_to_user()
+ */
+#define kdbus_member_set_user(_s, _b, _t, _m) \
+({ \
+ u64 __user *_sz = \
+ (void __user *)((u8 __user *)(_b) + offsetof(_t, _m)); \
+ copy_to_user(_sz, _s, sizeof(((_t *)0)->_m)); \
+})
+
+/**
+ * kdbus_strhash - calculate a hash
+ * @str: String
+ *
+ * Return: hash value
+ */
+static inline unsigned int kdbus_strhash(const char *str)
+{
+ unsigned long hash = init_name_hash();
+
+ while (*str)
+ hash = partial_name_hash(*str++, hash);
+
+ return end_name_hash(hash);
+}
+
+int kdbus_verify_uid_prefix(const char *name, struct user_namespace *user_ns,
+ kuid_t kuid);
+int kdbus_sanitize_attach_flags(u64 flags, u64 *attach_flags);
+
+int kdbus_copy_from_user(void *dest, void __user *user_ptr, size_t size);
+void *kdbus_memdup_user(void __user *user_ptr, size_t sz_min, size_t sz_max);
+
+struct kvec;
+
+void kdbus_kvec_set(struct kvec *kvec, void *src, size_t len, u64 *total_len);
+size_t kdbus_kvec_pad(struct kvec *kvec, u64 *len);
+
+#endif
generated by cgit v1.2.3 (git 2.39.1) at 2025-12-08 16:46:02 +0000