diff options
| -rw-r--r-- | ipc/kdbus/connection.c | 2215 | ||||
| -rw-r--r-- | ipc/kdbus/connection.h | 257 | ||||
| -rw-r--r-- | ipc/kdbus/item.c | 339 | ||||
| -rw-r--r-- | ipc/kdbus/item.h | 64 | ||||
| -rw-r--r-- | ipc/kdbus/message.c | 616 | ||||
| -rw-r--r-- | ipc/kdbus/message.h | 133 | ||||
| -rw-r--r-- | ipc/kdbus/queue.c | 678 | ||||
| -rw-r--r-- | ipc/kdbus/queue.h | 92 | ||||
| -rw-r--r-- | ipc/kdbus/reply.c | 259 | ||||
| -rw-r--r-- | ipc/kdbus/reply.h | 68 | ||||
| -rw-r--r-- | ipc/kdbus/util.h | 2 |
11 files changed, 4722 insertions, 1 deletions
diff --git a/ipc/kdbus/connection.c b/ipc/kdbus/connection.c new file mode 100644 index 00000000000..e554f1a71aa --- /dev/null +++ b/ipc/kdbus/connection.c @@ -0,0 +1,2215 @@ +/* + * 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/audit.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/fs_struct.h> +#include <linux/hashtable.h> +#include <linux/idr.h> +#include <linux/init.h> +#include <linux/math64.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/path.h> +#include <linux/poll.h> +#include <linux/sched.h> +#include <linux/shmem_fs.h> +#include <linux/sizes.h> +#include <linux/slab.h> +#include <linux/syscalls.h> +#include <linux/uio.h> + +#include "bus.h" +#include "connection.h" +#include "endpoint.h" +#include "handle.h" +#include "match.h" +#include "message.h" +#include "metadata.h" +#include "names.h" +#include "domain.h" +#include "item.h" +#include "notify.h" +#include "policy.h" +#include "pool.h" +#include "reply.h" +#include "util.h" +#include "queue.h" + +#define KDBUS_CONN_ACTIVE_BIAS (INT_MIN + 2) +#define KDBUS_CONN_ACTIVE_NEW (INT_MIN + 1) + +static struct kdbus_conn *kdbus_conn_new(struct kdbus_ep *ep, bool privileged, + struct kdbus_cmd_hello *hello, + const char *name, + const struct kdbus_creds *creds, + const struct kdbus_pids *pids, + const char *seclabel, + const char *conn_description) +{ +#ifdef CONFIG_DEBUG_LOCK_ALLOC + static struct lock_class_key __key; +#endif + struct kdbus_pool_slice *slice = NULL; + struct kdbus_bus *bus = ep->bus; + struct kdbus_conn *conn; + u64 attach_flags_send; + u64 attach_flags_recv; + u64 items_size = 0; + bool is_policy_holder; + bool is_activator; + bool is_monitor; + struct kvec kvec; + int ret; + + struct { + u64 size; + u64 type; + struct kdbus_bloom_parameter bloom; + } bloom_item; + + is_monitor = hello->flags & KDBUS_HELLO_MONITOR; + is_activator = hello->flags & KDBUS_HELLO_ACTIVATOR; + is_policy_holder = hello->flags & KDBUS_HELLO_POLICY_HOLDER; + + if (!hello->pool_size || !IS_ALIGNED(hello->pool_size, PAGE_SIZE)) + return ERR_PTR(-EINVAL); + if (is_monitor + is_activator + is_policy_holder > 1) + return ERR_PTR(-EINVAL); + if (name && !is_activator && !is_policy_holder) + return ERR_PTR(-EINVAL); + if (!name && (is_activator || is_policy_holder)) + return ERR_PTR(-EINVAL); + if (name && !kdbus_name_is_valid(name, true)) + return ERR_PTR(-EINVAL); + if (is_monitor && ep->user) + return ERR_PTR(-EOPNOTSUPP); + if (!privileged && (is_activator || is_policy_holder || is_monitor)) + return ERR_PTR(-EPERM); + if ((creds || pids || seclabel) && !privileged) + return ERR_PTR(-EPERM); + + ret = kdbus_sanitize_attach_flags(hello->attach_flags_send, + &attach_flags_send); + if (ret < 0) + return ERR_PTR(ret); + + ret = kdbus_sanitize_attach_flags(hello->attach_flags_recv, + &attach_flags_recv); + if (ret < 0) + return ERR_PTR(ret); + + /* The attach flags must always satisfy the bus requirements. */ + if (bus->attach_flags_req & ~attach_flags_send) + return ERR_PTR(-ECONNREFUSED); + + conn = kzalloc(sizeof(*conn), GFP_KERNEL); + if (!conn) + return ERR_PTR(-ENOMEM); + + kref_init(&conn->kref); + atomic_set(&conn->active, KDBUS_CONN_ACTIVE_NEW); +#ifdef CONFIG_DEBUG_LOCK_ALLOC + lockdep_init_map(&conn->dep_map, "s_active", &__key, 0); +#endif + mutex_init(&conn->lock); + INIT_LIST_HEAD(&conn->names_list); + INIT_LIST_HEAD(&conn->names_queue_list); + INIT_LIST_HEAD(&conn->reply_list); + atomic_set(&conn->name_count, 0); + atomic_set(&conn->request_count, 0); + atomic_set(&conn->lost_count, 0); + INIT_DELAYED_WORK(&conn->work, kdbus_reply_list_scan_work); + conn->cred = get_current_cred(); + init_waitqueue_head(&conn->wait); + kdbus_queue_init(&conn->queue); + conn->privileged = privileged; + conn->ep = kdbus_ep_ref(ep); + conn->id = atomic64_inc_return(&bus->domain->last_id); + conn->flags = hello->flags; + atomic64_set(&conn->attach_flags_send, attach_flags_send); + atomic64_set(&conn->attach_flags_recv, attach_flags_recv); + INIT_LIST_HEAD(&conn->monitor_entry); + + if (conn_description) { + conn->description = kstrdup(conn_description, GFP_KERNEL); + if (!conn->description) { + ret = -ENOMEM; + goto exit_unref; + } + } + + conn->pool = kdbus_pool_new(conn->description, hello->pool_size); + if (IS_ERR(conn->pool)) { + ret = PTR_ERR(conn->pool); + conn->pool = NULL; + goto exit_unref; + } + + conn->match_db = kdbus_match_db_new(); + if (IS_ERR(conn->match_db)) { + ret = PTR_ERR(conn->match_db); + conn->match_db = NULL; + goto exit_unref; + } + + /* return properties of this connection to the caller */ + hello->bus_flags = bus->bus_flags; + hello->id = conn->id; + + BUILD_BUG_ON(sizeof(bus->id128) != sizeof(hello->id128)); + memcpy(hello->id128, bus->id128, sizeof(hello->id128)); + + conn->meta = kdbus_meta_proc_new(); + if (IS_ERR(conn->meta)) { + ret = PTR_ERR(conn->meta); + conn->meta = NULL; + goto exit_unref; + } + + /* privileged processes can impersonate somebody else */ + if (creds || pids || seclabel) { + ret = kdbus_meta_proc_fake(conn->meta, creds, pids, seclabel); + if (ret < 0) + goto exit_unref; + + conn->faked_meta = true; + } else { + ret = kdbus_meta_proc_collect(conn->meta, + KDBUS_ATTACH_CREDS | + KDBUS_ATTACH_PIDS | + KDBUS_ATTACH_AUXGROUPS | + KDBUS_ATTACH_TID_COMM | + KDBUS_ATTACH_PID_COMM | + KDBUS_ATTACH_EXE | + KDBUS_ATTACH_CMDLINE | + KDBUS_ATTACH_CGROUP | + KDBUS_ATTACH_CAPS | + KDBUS_ATTACH_SECLABEL | + KDBUS_ATTACH_AUDIT); + if (ret < 0) + goto exit_unref; + } + + /* + * Account the connection against the current user (UID), or for + * custom endpoints use the anonymous user assigned to the endpoint. + * Note that limits are always accounted against the real UID, not + * the effective UID (cred->user always points to the accounting of + * cred->uid, not cred->euid). + */ + if (ep->user) { + conn->user = kdbus_user_ref(ep->user); + } else { + conn->user = kdbus_user_lookup(ep->bus->domain, current_uid()); + if (IS_ERR(conn->user)) { + ret = PTR_ERR(conn->user); + conn->user = NULL; + goto exit_unref; + } + } + + if (atomic_inc_return(&conn->user->connections) > KDBUS_USER_MAX_CONN) { + /* decremented by destructor as conn->user is valid */ + ret = -EMFILE; + goto exit_unref; + } + + bloom_item.size = sizeof(bloom_item); + bloom_item.type = KDBUS_ITEM_BLOOM_PARAMETER; + bloom_item.bloom = bus->bloom; + kdbus_kvec_set(&kvec, &bloom_item, bloom_item.size, &items_size); + + slice = kdbus_pool_slice_alloc(conn->pool, items_size, false); + if (IS_ERR(slice)) { + ret = PTR_ERR(slice); + slice = NULL; + goto exit_unref; + } + + ret = kdbus_pool_slice_copy_kvec(slice, 0, &kvec, 1, items_size); + if (ret < 0) + goto exit_unref; + + kdbus_pool_slice_publish(slice, &hello->offset, &hello->items_size); + kdbus_pool_slice_release(slice); + + return conn; + +exit_unref: + kdbus_pool_slice_release(slice); + kdbus_conn_unref(conn); + return ERR_PTR(ret); +} + +static void __kdbus_conn_free(struct kref *kref) +{ + struct kdbus_conn *conn = container_of(kref, struct kdbus_conn, kref); + + WARN_ON(kdbus_conn_active(conn)); + WARN_ON(delayed_work_pending(&conn->work)); + WARN_ON(!list_empty(&conn->queue.msg_list)); + WARN_ON(!list_empty(&conn->names_list)); + WARN_ON(!list_empty(&conn->names_queue_list)); + WARN_ON(!list_empty(&conn->reply_list)); + + if (conn->user) { + atomic_dec(&conn->user->connections); + kdbus_user_unref(conn->user); + } + + kdbus_meta_proc_unref(conn->meta); + kdbus_match_db_free(conn->match_db); + kdbus_pool_free(conn->pool); + kdbus_ep_unref(conn->ep); + put_cred(conn->cred); + kfree(conn->description); + kfree(conn->quota); + kfree(conn); +} + +/** + * kdbus_conn_ref() - take a connection reference + * @conn: Connection, may be %NULL + * + * Return: the connection itself + */ +struct kdbus_conn *kdbus_conn_ref(struct kdbus_conn *conn) +{ + if (conn) + kref_get(&conn->kref); + return conn; +} + +/** + * kdbus_conn_unref() - drop a connection reference + * @conn: Connection (may be NULL) + * + * When the last reference is dropped, the connection's internal structure + * is freed. + * + * Return: NULL + */ +struct kdbus_conn *kdbus_conn_unref(struct kdbus_conn *conn) +{ + if (conn) + kref_put(&conn->kref, __kdbus_conn_free); + return NULL; +} + +/** + * kdbus_conn_active() - connection is not disconnected + * @conn: Connection to check + * + * Return true if the connection was not disconnected, yet. Note that a + * connection might be disconnected asynchronously, unless you hold the + * connection lock. If that's not suitable for you, see kdbus_conn_acquire() to + * suppress connection shutdown for a short period. + * + * Return: true if the connection is still active + */ +bool kdbus_conn_active(const struct kdbus_conn *conn) +{ + return atomic_read(&conn->active) >= 0; +} + +/** + * kdbus_conn_acquire() - acquire an active connection reference + * @conn: Connection + * + * Users can close a connection via KDBUS_BYEBYE (or by destroying the + * endpoint/bus/...) at any time. Whenever this happens, we should deny any + * user-visible action on this connection and signal ECONNRESET instead. + * To avoid testing for connection availability everytime you take the + * connection-lock, you can acquire a connection for short periods. + * + * By calling kdbus_conn_acquire(), you gain an "active reference" to the + * connection. You must also hold a regular reference at any time! As long as + * you hold the active-ref, the connection will not be shut down. However, if + * the connection was shut down, you can never acquire an active-ref again. + * + * kdbus_conn_disconnect() disables the connection and then waits for all active + * references to be dropped. It will also wake up any pending operation. + * However, you must not sleep for an indefinite period while holding an + * active-reference. Otherwise, kdbus_conn_disconnect() might stall. If you need + * to sleep for an indefinite period, either release the reference and try to + * acquire it again after waking up, or make kdbus_conn_disconnect() wake up + * your wait-queue. + * + * Return: 0 on success, negative error code on failure. + */ +int kdbus_conn_acquire(struct kdbus_conn *conn) +{ + if (!atomic_inc_unless_negative(&conn->active)) + return -ECONNRESET; + +#ifdef CONFIG_DEBUG_LOCK_ALLOC + rwsem_acquire_read(&conn->dep_map, 0, 1, _RET_IP_); +#endif + + return 0; +} + +/** + * kdbus_conn_release() - release an active connection reference + * @conn: Connection + * + * This releases an active reference that has been acquired via + * kdbus_conn_acquire(). If the connection was already disabled and this is the + * last active-ref that is dropped, the disconnect-waiter will be woken up and + * properly close the connection. + */ +void kdbus_conn_release(struct kdbus_conn *conn) +{ + int v; + + if (!conn) + return; + +#ifdef CONFIG_DEBUG_LOCK_ALLOC + rwsem_release(&conn->dep_map, 1, _RET_IP_); +#endif + + v = atomic_dec_return(&conn->active); + if (v != KDBUS_CONN_ACTIVE_BIAS) + return; + + wake_up_all(&conn->wait); +} + +static int kdbus_conn_connect(struct kdbus_conn *conn, const char *name) +{ + struct kdbus_ep *ep = conn->ep; + struct kdbus_bus *bus = ep->bus; + int ret; + + if (WARN_ON(atomic_read(&conn->active) != KDBUS_CONN_ACTIVE_NEW)) + return -EALREADY; + + /* make sure the ep-node is active while we add our connection */ + if (!kdbus_node_acquire(&ep->node)) + return -ESHUTDOWN; + + /* lock order: domain -> bus -> ep -> names -> conn */ + mutex_lock(&ep->lock); + down_write(&bus->conn_rwlock); + + /* link into monitor list */ + if (kdbus_conn_is_monitor(conn)) + list_add_tail(&conn->monitor_entry, &bus->monitors_list); + + /* link into bus and endpoint */ + list_add_tail(&conn->ep_entry, &ep->conn_list); + hash_add(bus->conn_hash, &conn->hentry, conn->id); + + /* enable lookups and acquire active ref */ + atomic_set(&conn->active, 1); +#ifdef CONFIG_DEBUG_LOCK_ALLOC + rwsem_acquire_read(&conn->dep_map, 0, 1, _RET_IP_); +#endif + + up_write(&bus->conn_rwlock); + mutex_unlock(&ep->lock); + + kdbus_node_release(&ep->node); + + /* + * Notify subscribers about the new active connection, unless it is + * a monitor. Monitors are invisible on the bus, can't be addressed + * directly, and won't cause any notifications. + */ + if (!kdbus_conn_is_monitor(conn)) { + ret = kdbus_notify_id_change(conn->ep->bus, KDBUS_ITEM_ID_ADD, + conn->id, conn->flags); + if (ret < 0) + goto exit_disconnect; + } + + if (kdbus_conn_is_activator(conn)) { + u64 flags = KDBUS_NAME_ACTIVATOR; + + if (WARN_ON(!name)) { + ret = -EINVAL; + goto exit_disconnect; + } + + ret = kdbus_name_acquire(bus->name_registry, conn, name, + flags, NULL); + if (ret < 0) + goto exit_disconnect; + } + + kdbus_conn_release(conn); + kdbus_notify_flush(bus); + return 0; + +exit_disconnect: + kdbus_conn_release(conn); + kdbus_conn_disconnect(conn, false); + return ret; +} + +/** + * kdbus_conn_disconnect() - disconnect a connection + * @conn: The connection to disconnect + * @ensure_queue_empty: Flag to indicate if the call should fail in + * case the connection's message list is not + * empty + * + * If @ensure_msg_list_empty is true, and the connection has pending messages, + * -EBUSY is returned. + * + * Return: 0 on success, negative errno on failure + */ +int kdbus_conn_disconnect(struct kdbus_conn *conn, bool ensure_queue_empty) +{ + struct kdbus_queue_entry *entry, *tmp; + struct kdbus_bus *bus = conn->ep->bus; + struct kdbus_reply *r, *r_tmp; + struct kdbus_conn *c; + int i, v; + + mutex_lock(&conn->lock); + v = atomic_read(&conn->active); + if (v == KDBUS_CONN_ACTIVE_NEW) { + /* was never connected */ + mutex_unlock(&conn->lock); + return 0; + } + if (v < 0) { + /* already dead */ + mutex_unlock(&conn->lock); + return -ECONNRESET; + } + if (ensure_queue_empty && !list_empty(&conn->queue.msg_list)) { + /* still busy */ + mutex_unlock(&conn->lock); + return -EBUSY; + } + + atomic_add(KDBUS_CONN_ACTIVE_BIAS, &conn->active); + mutex_unlock(&conn->lock); + + wake_up_interruptible(&conn->wait); + +#ifdef CONFIG_DEBUG_LOCK_ALLOC + rwsem_acquire(&conn->dep_map, 0, 0, _RET_IP_); + if (atomic_read(&conn->active) != KDBUS_CONN_ACTIVE_BIAS) + lock_contended(&conn->dep_map, _RET_IP_); +#endif + + wait_event(conn->wait, + atomic_read(&conn->active) == KDBUS_CONN_ACTIVE_BIAS); + +#ifdef CONFIG_DEBUG_LOCK_ALLOC + lock_acquired(&conn->dep_map, _RET_IP_); + rwsem_release(&conn->dep_map, 1, _RET_IP_); +#endif + + cancel_delayed_work_sync(&conn->work); + kdbus_policy_remove_owner(&conn->ep->bus->policy_db, conn); + + /* lock order: domain -> bus -> ep -> names -> conn */ + mutex_lock(&conn->ep->lock); + down_write(&bus->conn_rwlock); + + /* remove from bus and endpoint */ + hash_del(&conn->hentry); + list_del(&conn->monitor_entry); + list_del(&conn->ep_entry); + + up_write(&bus->conn_rwlock); + mutex_unlock(&conn->ep->lock); + + /* + * Remove all names associated with this connection; this possibly + * moves queued messages back to the activator connection. + */ + kdbus_name_release_all(bus->name_registry, conn); + + /* if we die while other connections wait for our reply, notify them */ + mutex_lock(&conn->lock); + list_for_each_entry_safe(entry, tmp, &conn->queue.msg_list, entry) { + if (entry->reply) + kdbus_notify_reply_dead(bus, + entry->reply->reply_dst->id, + entry->reply->cookie); + kdbus_queue_entry_free(entry); + } + + list_for_each_entry_safe(r, r_tmp, &conn->reply_list, entry) + kdbus_reply_unlink(r); + mutex_unlock(&conn->lock); + + /* lock order: domain -> bus -> ep -> names -> conn */ + down_read(&bus->conn_rwlock); + hash_for_each(bus->conn_hash, i, c, hentry) { + mutex_lock(&c->lock); + list_for_each_entry_safe(r, r_tmp, &c->reply_list, entry) { + if (r->reply_src == conn) { + if (r->sync) { + kdbus_sync_reply_wakeup(r, -EPIPE); + kdbus_reply_unlink(r); + continue; + } + + /* send a 'connection dead' notification */ + kdbus_notify_reply_dead(bus, c->id, r->cookie); + kdbus_reply_unlink(r); + } + } + mutex_unlock(&c->lock); + } + up_read(&bus->conn_rwlock); + + if (!kdbus_conn_is_monitor(conn)) + kdbus_notify_id_change(bus, KDBUS_ITEM_ID_REMOVE, + conn->id, conn->flags); + + kdbus_notify_flush(bus); + + return 0; +} + +/** + * kdbus_conn_has_name() - check if a connection owns a name + * @conn: Connection + * @name: Well-know name to check for + * + * The caller must hold the registry lock of conn->ep->bus. + * + * Return: true if the name is currently owned by the connection + */ +bool kdbus_conn_has_name(struct kdbus_conn *conn, const char *name) +{ + struct kdbus_name_entry *e; + + lockdep_assert_held(&conn->ep->bus->name_registry->rwlock); + + list_for_each_entry(e, &conn->names_list, conn_entry) + if (strcmp(e->name, name) == 0) + return true; + + return false; +} + +struct kdbus_quota { + uint32_t memory; + uint16_t msgs; + uint8_t fds; +}; + +/** + * kdbus_conn_quota_inc() - increase quota accounting + * @c: connection owning the quota tracking + * @u: user to account for (or NULL for kernel accounting) + * @memory: size of memory to account for + * @fds: number of FDs to account for + * + * This call manages the quotas on resource @c. That is, it's used if other + * users want to use the resources of connection @c, which so far only concerns + * the receive queue of the destination. + * + * This increases the quota-accounting for user @u by @memory bytes and @fds + * file descriptors. If the user has already reached the quota limits, this call + * will not do any accounting but return a negative error code indicating the + * failure. + * + * Return: 0 on success, negative error code on failure. + */ +int kdbus_conn_quota_inc(struct kdbus_conn *c, struct kdbus_user *u, + size_t memory, size_t fds) +{ + struct kdbus_quota *quota; + size_t available, accounted; + unsigned int id; + + /* + * Pool Layout: + * 50% of a pool is always owned by the connection. It is reserved for + * kernel queries, handling received messages and other tasks that are + * under control of the pool owner. The other 50% of the pool are used + * as incoming queue. + * As we optionally support user-space based policies, we need fair + * allocation schemes. Furthermore, resource utilization should be + * maximized, so only minimal resources stay reserved. However, we need + * to adapt to a dynamic number of users, as we cannot know how many + * users will talk to a connection. Therefore, the current allocations + * works like this: + * We limit the number of bytes in a destination's pool per sending + * user. The space available for a user is 33% of the unused pool space + * (whereas the space used by the user itself is also treated as + * 'unused'). This way, we favor users coming first, but keep enough + * pool space available for any following users. Given that messages are + * dequeued in FIFO order, this should balance nicely if the number of + * users grows. At the same time, this algorithm guarantees that the + * space available to a connection is reduced dynamically, the more + * concurrent users talk to a connection. + */ + + /* per user-accounting is expensive, so we keep state small */ + BUILD_BUG_ON(sizeof(quota->memory) != 4); + BUILD_BUG_ON(sizeof(quota->msgs) != 2); + BUILD_BUG_ON(sizeof(quota->fds) != 1); + BUILD_BUG_ON(KDBUS_CONN_MAX_MSGS > U16_MAX); + BUILD_BUG_ON(KDBUS_CONN_MAX_FDS_PER_USER > U8_MAX); + + id = u ? u->id : KDBUS_USER_KERNEL_ID; + if (id >= c->n_quota) { + unsigned int users; + + users = max(KDBUS_ALIGN8(id) + 8, id); + quota = krealloc(c->quota, users * sizeof(*quota), + GFP_KERNEL | __GFP_ZERO); + if (!quota) + return -ENOMEM; + + c->n_quota = users; + c->quota = quota; + } + + quota = &c->quota[id]; + kdbus_pool_accounted(c->pool, &available, &accounted); + + /* half the pool is _always_ reserved for the pool owner */ + available /= 2; + + /* + * Pool owner slices are un-accounted slices; they can claim more + * than 50% of the queue. However, the slice we're dealing with here + * belong to the incoming queue, hence they are 'accounted' slices + * to which the 50%-limit applies. + */ + if (available < accounted) + return -ENOBUFS; + + /* 1/3 of the remaining space (including your own memory) */ + available = (available - accounted + quota->memory) / 3; + + if (available < quota->memory || + available - quota->memory < memory || + quota->memory + memory > U32_MAX) + return -ENOBUFS; + if (quota->msgs >= KDBUS_CONN_MAX_MSGS) + return -ENOBUFS; + if (quota->fds + fds < quota->fds || + quota->fds + fds > KDBUS_CONN_MAX_FDS_PER_USER) + return -EMFILE; + + quota->memory += memory; + quota->fds += fds; + ++quota->msgs; + return 0; +} + +/** + * kdbus_conn_quota_dec() - decrease quota accounting + * @c: connection owning the quota tracking + * @u: user which was accounted for (or NULL for kernel accounting) + * @memory: size of memory which was accounted for + * @fds: number of FDs which were accounted for + * + * This does the reverse of kdbus_conn_quota_inc(). You have to release any + * accounted resources that you called kdbus_conn_quota_inc() for. However, you + * must not call kdbus_conn_quota_dec() if the accounting failed (that is, + * kdbus_conn_quota_inc() failed). + */ +void kdbus_conn_quota_dec(struct kdbus_conn *c, struct kdbus_user *u, + size_t memory, size_t fds) +{ + struct kdbus_quota *quota; + unsigned int id; + + id = u ? u->id : KDBUS_USER_KERNEL_ID; + if (WARN_ON(id >= c->n_quota)) + return; + + quota = &c->quota[id]; + + if (!WARN_ON(quota->msgs == 0)) + --quota->msgs; + if (!WARN_ON(quota->memory < memory)) + quota->memory -= memory; + if (!WARN_ON(quota->fds < fds)) + quota->fds -= fds; +} + +/** + * kdbus_conn_lost_message() - handle lost messages + * @c: connection that lost a message + * + * kdbus is reliable. That means, we try hard to never lose messages. However, + * memory is limited, so we cannot rely on transmissions to never fail. + * Therefore, we use quota-limits to let callers know if there unicast message + * cannot be transmitted to a peer. This works fine for unicasts, but for + * broadcasts we cannot make the caller handle the transmission failure. + * Instead, we must let the destination know that it couldn't receive a + * broadcast. + * As this is an unlikely scenario, we keep it simple. A single lost-counter + * remembers the number of lost messages since the last call to RECV. The next + * message retrieval will notify the connection that it lost messages since the + * last message retrieval and thus should resync its state. + */ +void kdbus_conn_lost_message(struct kdbus_conn *c) +{ + if (atomic_inc_return(&c->lost_count) == 1) + wake_up_interruptible(&c->wait); +} + +/* Callers should take the conn_dst lock */ +static struct kdbus_queue_entry * +kdbus_conn_entry_make(struct kdbus_conn *conn_dst, + const struct kdbus_kmsg *kmsg, + struct kdbus_user *user) +{ + struct kdbus_queue_entry *entry; + + /* The remote connection was disconnected */ + if (!kdbus_conn_active(conn_dst)) + return ERR_PTR(-ECONNRESET); + + /* + * If the connection does not accept file descriptors but the message + * has some attached, refuse it. + * + * If this is a monitor connection, accept the message. In that + * case, all file descriptors will be set to -1 at receive time. + */ + if (!kdbus_conn_is_monitor(conn_dst) && + !(conn_dst->flags & KDBUS_HELLO_ACCEPT_FD) && + kmsg->res && kmsg->res->fds_count > 0) + return ERR_PTR(-ECOMM); + + entry = kdbus_queue_entry_new(conn_dst, kmsg, user); + if (IS_ERR(entry)) + return entry; + + return entry; +} + +/* + * Synchronously responding to a message, allocate a queue entry + * and attach it to the reply tracking object. + * The connection's queue will never get to see it. + */ +static int kdbus_conn_entry_sync_attach(struct kdbus_conn *conn_dst, + const struct kdbus_kmsg *kmsg, + struct kdbus_reply *reply_wake) +{ + struct kdbus_queue_entry *entry; + int remote_ret; + int ret = 0; + + mutex_lock(&reply_wake->reply_dst->lock); + + /* + * If we are still waiting then proceed, allocate a queue + * entry and attach it to the reply object + */ + if (reply_wake->waiting) { + entry = kdbus_conn_entry_make(conn_dst, kmsg, + reply_wake->reply_src->user); + if (IS_ERR(entry)) + ret = PTR_ERR(entry); + else + /* Attach the entry to the reply object */ + reply_wake->queue_entry = entry; + } else { + ret = -ECONNRESET; + } + + /* + * Update the reply object and wake up remote peer only + * on appropriate return codes + * + * * -ECOMM: if the replying connection failed with -ECOMM + * then wakeup remote peer with -EREMOTEIO + * + * We do this to differenciate between -ECOMM errors + * from the original sender perspective: + * -ECOMM error during the sync send and + * -ECOMM error during the sync reply, this last + * one is rewritten to -EREMOTEIO + * + * * Wake up on all other return codes. + */ + remote_ret = ret; + + if (ret == -ECOMM) + remote_ret = -EREMOTEIO; + + kdbus_sync_reply_wakeup(reply_wake, remote_ret); + kdbus_reply_unlink(reply_wake); + mutex_unlock(&reply_wake->reply_dst->lock); + + return ret; +} + +/** + * kdbus_conn_entry_insert() - enqueue a message into the receiver's pool + * @conn_src: The sending connection + * @conn_dst: The connection to queue into + * @kmsg: The kmsg to queue + * @reply: The reply tracker to attach to the queue entry + * + * Return: 0 on success. negative error otherwise. + */ +int kdbus_conn_entry_insert(struct kdbus_conn *conn_src, + struct kdbus_conn *conn_dst, + const struct kdbus_kmsg *kmsg, + struct kdbus_reply *reply) +{ + struct kdbus_queue_entry *entry; + int ret; + + kdbus_conn_lock2(conn_src, conn_dst); + + entry = kdbus_conn_entry_make(conn_dst, kmsg, + conn_src ? conn_src->user : NULL); + if (IS_ERR(entry)) { + ret = PTR_ERR(entry); + goto exit_unlock; + } + + if (reply) { + kdbus_reply_link(reply); + if (!reply->sync) + schedule_delayed_work(&conn_src->work, 0); + } + + kdbus_queue_entry_enqueue(entry, reply); + wake_up_interruptible(&conn_dst->wait); + + ret = 0; + +exit_unlock: + kdbus_conn_unlock2(conn_src, conn_dst); + return ret; +} + +static int kdbus_conn_wait_reply(struct kdbus_conn *conn_src, + struct kdbus_cmd_send *cmd_send, + struct file *ioctl_file, + struct file *cancel_fd, + struct kdbus_reply *reply_wait, + ktime_t expire) +{ + struct kdbus_queue_entry *entry; + struct poll_wqueues pwq = {}; + int ret; + + if (WARN_ON(!reply_wait)) + return -EIO; + + /* + * Block until the reply arrives. reply_wait is left untouched + * by the timeout scans that might be conducted for other, + * asynchronous replies of conn_src. + */ + + poll_initwait(&pwq); + poll_wait(ioctl_file, &conn_src->wait, &pwq.pt); + + for (;;) { + /* + * Any of the following conditions will stop our synchronously + * blocking SEND command: + * + * a) The origin sender closed its connection + * b) The remote peer answered, setting reply_wait->waiting = 0 + * c) The cancel FD was written to + * d) A signal was received + * e) The specified timeout was reached, and none of the above + * conditions kicked in. + */ + + /* + * We have already acquired an active reference when + * entering here, but another thread may call + * KDBUS_CMD_BYEBYE which does not acquire an active + * reference, therefore kdbus_conn_disconnect() will + * not wait for us. + */ + if (!kdbus_conn_active(conn_src)) { + ret = -ECONNRESET; + break; + } + + /* + * After the replying peer unset the waiting variable + * it will wake up us. + */ + if (!reply_wait->waiting) { + ret = reply_wait->err; + break; + } + + if (cancel_fd) { + unsigned int r; + + r = cancel_fd->f_op->poll(cancel_fd, &pwq.pt); + if (r & POLLIN) { + ret = -ECANCELED; + break; + } + } + + if (signal_pending(current)) { + ret = -EINTR; + break; + } + + if (!poll_schedule_timeout(&pwq, TASK_INTERRUPTIBLE, + &expire, 0)) { + ret = -ETIMEDOUT; + break; + } + + /* + * Reset the poll worker func, so the waitqueues are not + * added to the poll table again. We just reuse what we've + * collected earlier for further iterations. + */ + init_poll_funcptr(&pwq.pt, NULL); + } + + poll_freewait(&pwq); + + if (ret == -EINTR) { + /* + * Interrupted system call. Unref the reply object, and pass + * the return value down the chain. Mark the reply as + * interrupted, so the cleanup work can remove it, but do not + * unlink it from the list. Once the syscall restarts, we'll + * pick it up and wait on it again. + */ + mutex_lock(&conn_src->lock); + reply_wait->interrupted = true; + schedule_delayed_work(&conn_src->work, 0); + mutex_unlock(&conn_src->lock); + + return -ERESTARTSYS; + } + + mutex_lock(&conn_src->lock); + reply_wait->waiting = false; + entry = reply_wait->queue_entry; + if (entry) { + ret = kdbus_queue_entry_install(entry, + &cmd_send->reply.return_flags, + true); + kdbus_pool_slice_publish(entry->slice, &cmd_send->reply.offset, + &cmd_send->reply.msg_size); + kdbus_queue_entry_free(entry); + } + kdbus_reply_unlink(reply_wait); + mutex_unlock(&conn_src->lock); + + return ret; +} + +static int kdbus_pin_dst(struct kdbus_bus *bus, + struct kdbus_kmsg *kmsg, + struct kdbus_name_entry **out_name, + struct kdbus_conn **out_dst) +{ + struct kdbus_msg_resources *res = kmsg->res; + struct kdbus_name_entry *name = NULL; + struct kdbus_conn *dst = NULL; + struct kdbus_msg *msg = &kmsg->msg; + int ret; + + if (WARN_ON(!res)) + return -EINVAL; + + lockdep_assert_held(&bus->name_registry->rwlock); + + if (!res->dst_name) { + dst = kdbus_bus_find_conn_by_id(bus, msg->dst_id); + if (!dst) + return -ENXIO; + + if (!kdbus_conn_is_ordinary(dst)) { + ret = -ENXIO; + goto error; + } + } else { + name = kdbus_name_lookup_unlocked(bus->name_registry, + res->dst_name); + if (!name) + return -ESRCH; + + /* + * If both a name and a connection ID are given as destination + * of a message, check that the currently owning connection of + * the name matches the specified ID. + * This way, we allow userspace to send the message to a + * specific connection by ID only if the connection currently + * owns the given name. + */ + if (msg->dst_id != KDBUS_DST_ID_NAME && + msg->dst_id != name->conn->id) + return -EREMCHG; + + if (!name->conn && name->activator) + dst = kdbus_conn_ref(name->activator); + else + dst = kdbus_conn_ref(name->conn); + + if ((msg->flags & KDBUS_MSG_NO_AUTO_START) && + kdbus_conn_is_activator(dst)) { + ret = -EADDRNOTAVAIL; + goto error; + } + + /* + * Record the sequence number of the registered name; it will + * be passed on to the queue, in case messages addressed to a + * name need to be moved from or to an activator. + */ + kmsg->dst_name_id = name->name_id; + } + + *out_name = name; + *out_dst = dst; + return 0; + +error: + kdbus_conn_unref(dst); + return ret; +} + +static int kdbus_conn_reply(struct kdbus_conn *src, struct kdbus_kmsg *kmsg) +{ + struct kdbus_name_entry *name = NULL; + struct kdbus_reply *reply, *wake = NULL; + struct kdbus_conn *dst = NULL; + struct kdbus_bus *bus = src->ep->bus; + u64 attach; + int ret; + + if (WARN_ON(kmsg->msg.dst_id == KDBUS_DST_ID_BROADCAST) || + WARN_ON(kmsg->msg.flags & KDBUS_MSG_EXPECT_REPLY) || + WARN_ON(kmsg->msg.flags & KDBUS_MSG_SIGNAL)) + return -EINVAL; + + /* name-registry must be locked for lookup *and* collecting data */ + down_read(&bus->name_registry->rwlock); + + /* find and pin destination */ + + ret = kdbus_pin_dst(bus, kmsg, &name, &dst); + if (ret < 0) + goto exit; + + mutex_lock(&dst->lock); + reply = kdbus_reply_find(src, dst, kmsg->msg.cookie_reply); + if (reply) { + if (reply->sync) + wake = kdbus_reply_ref(reply); + kdbus_reply_unlink(reply); + } + mutex_unlock(&dst->lock); + + if (!reply) { + ret = -EPERM; + goto exit; + } + + /* attach metadata */ + + attach = kdbus_meta_calc_attach_flags(src, dst); + + if (!src->faked_meta) { + ret = kdbus_meta_proc_collect(kmsg->proc_meta, attach); + if (ret < 0) + goto exit; + } + + ret = kdbus_meta_conn_collect(kmsg->conn_meta, kmsg, src, attach); + if (ret < 0) + goto exit; + + /* send message */ + + kdbus_bus_eavesdrop(bus, src, kmsg); + + if (wake) + ret = kdbus_conn_entry_sync_attach(dst, kmsg, wake); + else + ret = kdbus_conn_entry_insert(src, dst, kmsg, NULL); + +exit: + up_read(&bus->name_registry->rwlock); + kdbus_reply_unref(wake); + kdbus_conn_unref(dst); + return ret; +} + +static struct kdbus_reply *kdbus_conn_call(struct kdbus_conn *src, + struct kdbus_kmsg *kmsg, + ktime_t exp) +{ + struct kdbus_name_entry *name = NULL; + struct kdbus_reply *wait = NULL; + struct kdbus_conn *dst = NULL; + struct kdbus_bus *bus = src->ep->bus; + u64 attach; + int ret; + + if (WARN_ON(kmsg->msg.dst_id == KDBUS_DST_ID_BROADCAST) || + WARN_ON(kmsg->msg.flags & KDBUS_MSG_SIGNAL) || + WARN_ON(!(kmsg->msg.flags & KDBUS_MSG_EXPECT_REPLY))) + return ERR_PTR(-EINVAL); + + /* resume previous wait-context, if available */ + + mutex_lock(&src->lock); + wait = kdbus_reply_find(NULL, src, kmsg->msg.cookie); + if (wait) { + if (wait->interrupted) { + kdbus_reply_ref(wait); + wait->interrupted = false; + } else { + wait = NULL; + } + } + mutex_unlock(&src->lock); + + if (wait) + return wait; + + if (ktime_compare(ktime_get(), exp) >= 0) + return ERR_PTR(-ETIMEDOUT); + + /* name-registry must be locked for lookup *and* collecting data */ + down_read(&bus->name_registry->rwlock); + + /* find and pin destination */ + + ret = kdbus_pin_dst(bus, kmsg, &name, &dst); + if (ret < 0) + goto exit; + + if (!kdbus_conn_policy_talk(src, current_cred(), dst)) { + ret = -EPERM; + goto exit; + } + + wait = kdbus_reply_new(dst, src, &kmsg->msg, name, true); + if (IS_ERR(wait)) { + ret = PTR_ERR(wait); + wait = NULL; + goto exit; + } + + /* attach metadata */ + + attach = kdbus_meta_calc_attach_flags(src, dst); + + if (!src->faked_meta) { + ret = kdbus_meta_proc_collect(kmsg->proc_meta, attach); + if (ret < 0) + goto exit; + } + + ret = kdbus_meta_conn_collect(kmsg->conn_meta, kmsg, src, attach); + if (ret < 0) + goto exit; + + /* send message */ + + kdbus_bus_eavesdrop(bus, src, kmsg); + + ret = kdbus_conn_entry_insert(src, dst, kmsg, wait); + if (ret < 0) + goto exit; + + ret = 0; + +exit: + up_read(&bus->name_registry->rwlock); + if (ret < 0) { + kdbus_reply_unref(wait); + wait = ERR_PTR(ret); + } + kdbus_conn_unref(dst); + return wait; +} + +static int kdbus_conn_unicast(struct kdbus_conn *src, struct kdbus_kmsg *kmsg) +{ + struct kdbus_name_entry *name = NULL; + struct kdbus_reply *wait = NULL; + struct kdbus_conn *dst = NULL; + struct kdbus_bus *bus = src->ep->bus; + bool is_signal = (kmsg->msg.flags & KDBUS_MSG_SIGNAL); + u64 attach; + int ret = 0; + + if (WARN_ON(kmsg->msg.dst_id == KDBUS_DST_ID_BROADCAST) || + WARN_ON(!(kmsg->msg.flags & KDBUS_MSG_EXPECT_REPLY) && + kmsg->msg.cookie_reply != 0)) + return -EINVAL; + + /* name-registry must be locked for lookup *and* collecting data */ + down_read(&bus->name_registry->rwlock); + + /* find and pin destination */ + + ret = kdbus_pin_dst(bus, kmsg, &name, &dst); + if (ret < 0) + goto exit; + + if (is_signal) { + /* like broadcasts we eavesdrop even if the msg is dropped */ + kdbus_bus_eavesdrop(bus, src, kmsg); + + /* drop silently if peer is not interested or not privileged */ + if (!kdbus_match_db_match_kmsg(dst->match_db, src, kmsg) || + !kdbus_conn_policy_talk(dst, NULL, src)) + goto exit; + } else if (!kdbus_conn_policy_talk(src, current_cred(), dst)) { + ret = -EPERM; + goto exit; + } else if (kmsg->msg.flags & KDBUS_MSG_EXPECT_REPLY) { + wait = kdbus_reply_new(dst, src, &kmsg->msg, name, false); + if (IS_ERR(wait)) { + ret = PTR_ERR(wait); + wait = NULL; + goto exit; + } + } + + /* attach metadata */ + + attach = kdbus_meta_calc_attach_flags(src, dst); + + if (!src->faked_meta) { + ret = kdbus_meta_proc_collect(kmsg->proc_meta, attach); + if (ret < 0 && !is_signal) + goto exit; + } + + ret = kdbus_meta_conn_collect(kmsg->conn_meta, kmsg, src, attach); + if (ret < 0 && !is_signal) + goto exit; + + /* send message */ + + if (!is_signal) + kdbus_bus_eavesdrop(bus, src, kmsg); + + ret = kdbus_conn_entry_insert(src, dst, kmsg, wait); + if (ret < 0 && !is_signal) + goto exit; + + /* signals are treated like broadcasts, recv-errors are ignored */ + ret = 0; + +exit: + up_read(&bus->name_registry->rwlock); + kdbus_reply_unref(wait); + kdbus_conn_unref(dst); + return ret; +} + +/** + * kdbus_conn_move_messages() - move messages from one connection to another + * @conn_dst: Connection to copy to + * @conn_src: Connection to copy from + * @name_id: Filter for the sequence number of the registered + * name, 0 means no filtering. + * + * Move all messages from one connection to another. This is used when + * an implementer connection is taking over/giving back a well-known name + * from/to an activator connection. + */ +void kdbus_conn_move_messages(struct kdbus_conn *conn_dst, + struct kdbus_conn *conn_src, + u64 name_id) +{ + struct kdbus_queue_entry *e, *e_tmp; + struct kdbus_reply *r, *r_tmp; + struct kdbus_bus *bus; + struct kdbus_conn *c; + LIST_HEAD(msg_list); + int i, ret = 0; + + if (WARN_ON(conn_src == conn_dst)) + return; + + bus = conn_src->ep->bus; + + /* lock order: domain -> bus -> ep -> names -> conn */ + down_read(&bus->conn_rwlock); + hash_for_each(bus->conn_hash, i, c, hentry) { + if (c == conn_src || c == conn_dst) + continue; + + mutex_lock(&c->lock); + list_for_each_entry_safe(r, r_tmp, &c->reply_list, entry) { + if (r->reply_src != conn_src) + continue; + + /* filter messages for a specific name */ + if (name_id > 0 && r->name_id != name_id) + continue; + + kdbus_conn_unref(r->reply_src); + r->reply_src = kdbus_conn_ref(conn_dst); + } + mutex_unlock(&c->lock); + } + up_read(&bus->conn_rwlock); + + kdbus_conn_lock2(conn_src, conn_dst); + list_for_each_entry_safe(e, e_tmp, &conn_src->queue.msg_list, entry) { + /* filter messages for a specific name */ + if (name_id > 0 && e->dst_name_id != name_id) + continue; + + if (!(conn_dst->flags & KDBUS_HELLO_ACCEPT_FD) && + e->msg_res && e->msg_res->fds_count > 0) { + kdbus_conn_lost_message(conn_dst); + kdbus_queue_entry_free(e); + continue; + } + + ret = kdbus_queue_entry_move(e, conn_dst); + if (ret < 0) { + kdbus_conn_lost_message(conn_dst); + kdbus_queue_entry_free(e); + continue; + } + } + kdbus_conn_unlock2(conn_src, conn_dst); + + /* wake up poll() */ + wake_up_interruptible(&conn_dst->wait); +} + +/* query the policy-database for all names of @whom */ +static bool kdbus_conn_policy_query_all(struct kdbus_conn *conn, + const struct cred *conn_creds, + struct kdbus_policy_db *db, + struct kdbus_conn *whom, + unsigned int access) +{ + struct kdbus_name_entry *ne; + bool pass = false; + int res; + + lockdep_assert_held(&conn->ep->bus->name_registry->rwlock); + + down_read(&db->entries_rwlock); + mutex_lock(&whom->lock); + + list_for_each_entry(ne, &whom->names_list, conn_entry) { + res = kdbus_policy_query_unlocked(db, conn_creds ? : conn->cred, + ne->name, + kdbus_strhash(ne->name)); + if (res >= (int)access) { + pass = true; + break; + } + } + + mutex_unlock(&whom->lock); + up_read(&db->entries_rwlock); + + return pass; +} + +/** + * kdbus_conn_policy_own_name() - verify a connection can own the given name + * @conn: Connection + * @conn_creds: Credentials of @conn to use for policy check + * @name: Name + * + * This verifies that @conn is allowed to acquire the well-known name @name. + * + * Return: true if allowed, false if not. + */ +bool kdbus_conn_policy_own_name(struct kdbus_conn *conn, + const struct cred *conn_creds, + const char *name) +{ + unsigned int hash = kdbus_strhash(name); + int res; + + if (!conn_creds) + conn_creds = conn->cred; + + if (conn->ep->user) { + res = kdbus_policy_query(&conn->ep->policy_db, conn_creds, + name, hash); + if (res < KDBUS_POLICY_OWN) + return false; + } + + if (conn->privileged) + return true; + + res = kdbus_policy_query(&conn->ep->bus->policy_db, conn_creds, + name, hash); + return res >= KDBUS_POLICY_OWN; +} + +/** + * kdbus_conn_policy_talk() - verify a connection can talk to a given peer + * @conn: Connection that tries to talk + * @conn_creds: Credentials of @conn to use for policy check + * @to: Connection that is talked to + * + * This verifies that @conn is allowed to talk to @to. + * + * Return: true if allowed, false if not. + */ +bool kdbus_conn_policy_talk(struct kdbus_conn *conn, + const struct cred *conn_creds, + struct kdbus_conn *to) +{ + if (!conn_creds) + conn_creds = conn->cred; + + if (conn->ep->user && + !kdbus_conn_policy_query_all(conn, conn_creds, &conn->ep->policy_db, + to, KDBUS_POLICY_TALK)) + return false; + + if (conn->privileged) + return true; + if (uid_eq(conn_creds->euid, to->cred->uid)) + return true; + + return kdbus_conn_policy_query_all(conn, conn_creds, + &conn->ep->bus->policy_db, to, + KDBUS_POLICY_TALK); +} + +/** + * kdbus_conn_policy_see_name_unlocked() - verify a connection can see a given + * name + * @conn: Connection + * @conn_creds: Credentials of @conn to use for policy check + * @name: Name + * + * This verifies that @conn is allowed to see the well-known name @name. Caller + * must hold policy-lock. + * + * Return: true if allowed, false if not. + */ +bool kdbus_conn_policy_see_name_unlocked(struct kdbus_conn *conn, + const struct cred *conn_creds, + const char *name) +{ + int res; + + /* + * By default, all names are visible on a bus. SEE policies can only be + * installed on custom endpoints, where by default no name is visible. + */ + if (!conn->ep->user) + return true; + + res = kdbus_policy_query_unlocked(&conn->ep->policy_db, + conn_creds ? : conn->cred, + name, kdbus_strhash(name)); + return res >= KDBUS_POLICY_SEE; +} + +static bool kdbus_conn_policy_see_name(struct kdbus_conn *conn, + const struct cred *conn_creds, + const char *name) +{ + bool res; + + down_read(&conn->ep->policy_db.entries_rwlock); + res = kdbus_conn_policy_see_name_unlocked(conn, conn_creds, name); + up_read(&conn->ep->policy_db.entries_rwlock); + + return res; +} + +static bool kdbus_conn_policy_see(struct kdbus_conn *conn, + const struct cred *conn_creds, + struct kdbus_conn *whom) +{ + /* + * By default, all names are visible on a bus, so a connection can + * always see other connections. SEE policies can only be installed on + * custom endpoints, where by default no name is visible and we hide + * peers from each other, unless you see at least _one_ name of the + * peer. + */ + return !conn->ep->user || + kdbus_conn_policy_query_all(conn, conn_creds, + &conn->ep->policy_db, whom, + KDBUS_POLICY_SEE); +} + +/** + * kdbus_conn_policy_see_notification() - verify a connection is allowed to + * receive a given kernel notification + * @conn: Connection + * @conn_creds: Credentials of @conn to use for policy check + * @kmsg: The message carrying the notification + * + * This checks whether @conn is allowed to see the kernel notification @kmsg. + * + * Return: true if allowed, false if not. + */ +bool kdbus_conn_policy_see_notification(struct kdbus_conn *conn, + const struct cred *conn_creds, + const struct kdbus_kmsg *kmsg) +{ + if (WARN_ON(kmsg->msg.src_id != KDBUS_SRC_ID_KERNEL)) + return false; + + /* + * Depending on the notification type, broadcasted kernel notifications + * have to be filtered: + * + * KDBUS_ITEM_NAME_{ADD,REMOVE,CHANGE}: This notification is forwarded + * to a peer if, and only if, that peer can see the name this + * notification is for. + * + * KDBUS_ITEM_ID_{ADD,REMOVE}: As new peers cannot have names, and all + * names are dropped before a peer is removed, those notifications + * cannot be seen on custom endpoints. Thus, we only pass them + * through on default endpoints. + */ + + switch (kmsg->notify_type) { + case KDBUS_ITEM_NAME_ADD: + case KDBUS_ITEM_NAME_REMOVE: + case KDBUS_ITEM_NAME_CHANGE: + return kdbus_conn_policy_see_name(conn, conn_creds, + kmsg->notify_name); + + case KDBUS_ITEM_ID_ADD: + case KDBUS_ITEM_ID_REMOVE: + return !conn->ep->user; + + default: + WARN(1, "Invalid type for notification broadcast: %llu\n", + (unsigned long long)kmsg->notify_type); + return false; + } +} + +/** + * kdbus_cmd_hello() - handle KDBUS_CMD_HELLO + * @ep: Endpoint to operate on + * @privileged: Whether the caller is privileged + * @argp: Command payload + * + * Return: Newly created connection on success, ERR_PTR on failure. + */ +struct kdbus_conn *kdbus_cmd_hello(struct kdbus_ep *ep, bool privileged, + void __user *argp) +{ + struct kdbus_cmd_hello *cmd; + struct kdbus_conn *c = NULL; + const char *item_name; + int ret; + + struct kdbus_arg argv[] = { + { .type = KDBUS_ITEM_NEGOTIATE }, + { .type = KDBUS_ITEM_NAME }, + { .type = KDBUS_ITEM_CREDS }, + { .type = KDBUS_ITEM_PIDS }, + { .type = KDBUS_ITEM_SECLABEL }, + { .type = KDBUS_ITEM_CONN_DESCRIPTION }, + { .type = KDBUS_ITEM_POLICY_ACCESS, .multiple = true }, + }; + struct kdbus_args args = { + .allowed_flags = KDBUS_FLAG_NEGOTIATE | + KDBUS_HELLO_ACCEPT_FD | + KDBUS_HELLO_ACTIVATOR | + KDBUS_HELLO_POLICY_HOLDER | + KDBUS_HELLO_MONITOR, + .argv = argv, + .argc = ARRAY_SIZE(argv), + }; + + ret = kdbus_args_parse(&args, argp, &cmd); + if (ret < 0) + return ERR_PTR(ret); + if (ret > 0) + return NULL; + + item_name = argv[1].item ? argv[1].item->str : NULL; + + c = kdbus_conn_new(ep, privileged, cmd, item_name, + argv[2].item ? &argv[2].item->creds : NULL, + argv[3].item ? &argv[3].item->pids : NULL, + argv[4].item ? argv[4].item->str : NULL, + argv[5].item ? argv[5].item->str : NULL); + if (IS_ERR(c)) { + ret = PTR_ERR(c); + c = NULL; + goto exit; + } + + ret = kdbus_conn_connect(c, item_name); + if (ret < 0) + goto exit; + + if (kdbus_conn_is_activator(c) || kdbus_conn_is_policy_holder(c)) { + ret = kdbus_conn_acquire(c); + if (ret < 0) + goto exit; + + ret = kdbus_policy_set(&c->ep->bus->policy_db, args.items, + args.items_size, 1, + kdbus_conn_is_policy_holder(c), c); + kdbus_conn_release(c); + if (ret < 0) + goto exit; + } + + if (copy_to_user(argp, cmd, sizeof(*cmd))) + ret = -EFAULT; + +exit: + ret = kdbus_args_clear(&args, ret); + if (ret < 0) { + if (c) { + kdbus_conn_disconnect(c, false); + kdbus_conn_unref(c); + } + return ERR_PTR(ret); + } + return c; +} + +/** + * kdbus_cmd_byebye_unlocked() - handle KDBUS_CMD_BYEBYE + * @conn: connection to operate on + * @argp: command payload + * + * The caller must not hold any active reference to @conn or this will deadlock. + * + * Return: 0 on success, negative error code on failure. + */ +int kdbus_cmd_byebye_unlocked(struct kdbus_conn *conn, void __user *argp) +{ + struct kdbus_cmd *cmd; + int ret; + + struct kdbus_arg argv[] = { + { .type = KDBUS_ITEM_NEGOTIATE }, + }; + struct kdbus_args args = { + .allowed_flags = KDBUS_FLAG_NEGOTIATE, + .argv = argv, + .argc = ARRAY_SIZE(argv), + }; + + if (!kdbus_conn_is_ordinary(conn)) + return -EOPNOTSUPP; + + ret = kdbus_args_parse(&args, argp, &cmd); + if (ret != 0) + return ret; + + ret = kdbus_conn_disconnect(conn, true); + return kdbus_args_clear(&args, ret); +} + +/** + * kdbus_cmd_conn_info() - handle KDBUS_CMD_CONN_INFO + * @conn: connection to operate on + * @argp: command payload + * + * Return: 0 on success, negative error code on failure. + */ +int kdbus_cmd_conn_info(struct kdbus_conn *conn, void __user *argp) +{ + struct kdbus_meta_conn *conn_meta = NULL; + struct kdbus_pool_slice *slice = NULL; + struct kdbus_name_entry *entry = NULL; + struct kdbus_conn *owner_conn = NULL; + struct kdbus_info info = {}; + struct kdbus_cmd_info *cmd; + struct kdbus_bus *bus = conn->ep->bus; + struct kvec kvec; + size_t meta_size; + const char *name; + u64 attach_flags; + int ret; + + struct kdbus_arg argv[] = { + { .type = KDBUS_ITEM_NEGOTIATE }, + { .type = KDBUS_ITEM_NAME }, + }; + struct kdbus_args args = { + .allowed_flags = KDBUS_FLAG_NEGOTIATE, + .argv = argv, + .argc = ARRAY_SIZE(argv), + }; + + ret = kdbus_args_parse(&args, argp, &cmd); + if (ret != 0) + return ret; + + /* registry must be held throughout lookup *and* collecting data */ + down_read(&bus->name_registry->rwlock); + + ret = kdbus_sanitize_attach_flags(cmd->attach_flags, &attach_flags); + if (ret < 0) + goto exit; + + name = argv[1].item ? argv[1].item->str : NULL; + + if (name) { + entry = kdbus_name_lookup_unlocked(bus->name_registry, name); + if (!entry || !entry->conn || + !kdbus_conn_policy_see_name(conn, current_cred(), name) || + (cmd->id != 0 && entry->conn->id != cmd->id)) { + /* pretend a name doesn't exist if you cannot see it */ + ret = -ESRCH; + goto exit; + } + + owner_conn = kdbus_conn_ref(entry->conn); + } else if (cmd->id > 0) { + owner_conn = kdbus_bus_find_conn_by_id(bus, cmd->id); + if (!owner_conn || !kdbus_conn_policy_see(conn, current_cred(), + owner_conn)) { + /* pretend an id doesn't exist if you cannot see it */ + ret = -ENXIO; + goto exit; + } + } else { + ret = -EINVAL; + goto exit; + } + + info.id = owner_conn->id; + info.flags = owner_conn->flags; + kdbus_kvec_set(&kvec, &info, sizeof(info), &info.size); + + attach_flags &= atomic64_read(&owner_conn->attach_flags_send); + + conn_meta = kdbus_meta_conn_new(); + if (IS_ERR(conn_meta)) { + ret = PTR_ERR(conn_meta); + conn_meta = NULL; + goto exit; + } + + ret = kdbus_meta_conn_collect(conn_meta, NULL, owner_conn, + attach_flags); + if (ret < 0) + goto exit; + + ret = kdbus_meta_export_prepare(owner_conn->meta, conn_meta, + &attach_flags, &meta_size); + if (ret < 0) + goto exit; + + slice = kdbus_pool_slice_alloc(conn->pool, + info.size + meta_size, false); + if (IS_ERR(slice)) { + ret = PTR_ERR(slice); + slice = NULL; + goto exit; + } + + ret = kdbus_meta_export(owner_conn->meta, conn_meta, attach_flags, + slice, sizeof(info), &meta_size); + if (ret < 0) + goto exit; + + info.size += meta_size; + + ret = kdbus_pool_slice_copy_kvec(slice, 0, &kvec, 1, sizeof(info)); + if (ret < 0) + goto exit; + + kdbus_pool_slice_publish(slice, &cmd->offset, &cmd->info_size); + + if (kdbus_member_set_user(&cmd->offset, argp, typeof(*cmd), offset) || + kdbus_member_set_user(&cmd->info_size, argp, + typeof(*cmd), info_size)) { + ret = -EFAULT; + goto exit; + } + + ret = 0; + +exit: + up_read(&bus->name_registry->rwlock); + kdbus_pool_slice_release(slice); + kdbus_meta_conn_unref(conn_meta); + kdbus_conn_unref(owner_conn); + return kdbus_args_clear(&args, ret); +} + +/** + * kdbus_cmd_update() - handle KDBUS_CMD_UPDATE + * @conn: connection to operate on + * @argp: command payload + * + * Return: 0 on success, negative error code on failure. + */ +int kdbus_cmd_update(struct kdbus_conn *conn, void __user *argp) +{ + struct kdbus_bus *bus = conn->ep->bus; + struct kdbus_item *item_policy; + u64 *item_attach_send = NULL; + u64 *item_attach_recv = NULL; + struct kdbus_cmd *cmd; + u64 attach_send; + u64 attach_recv; + int ret; + + struct kdbus_arg argv[] = { + { .type = KDBUS_ITEM_NEGOTIATE }, + { .type = KDBUS_ITEM_ATTACH_FLAGS_SEND }, + { .type = KDBUS_ITEM_ATTACH_FLAGS_RECV }, + { .type = KDBUS_ITEM_NAME, .multiple = true }, + { .type = KDBUS_ITEM_POLICY_ACCESS, .multiple = true }, + }; + struct kdbus_args args = { + .allowed_flags = KDBUS_FLAG_NEGOTIATE, + .argv = argv, + .argc = ARRAY_SIZE(argv), + }; + + ret = kdbus_args_parse(&args, argp, &cmd); + if (ret != 0) + return ret; + + item_attach_send = argv[1].item ? &argv[1].item->data64[0] : NULL; + item_attach_recv = argv[2].item ? &argv[2].item->data64[0] : NULL; + item_policy = argv[3].item ? : argv[4].item; + + if (item_attach_send) { + if (!kdbus_conn_is_ordinary(conn) && + !kdbus_conn_is_monitor(conn)) { + ret = -EOPNOTSUPP; + goto exit; + } + + ret = kdbus_sanitize_attach_flags(*item_attach_send, + &attach_send); + if (ret < 0) + goto exit; + + if (bus->attach_flags_req & ~attach_send) { + ret = -EINVAL; + goto exit; + } + } + + if (item_attach_recv) { + if (!kdbus_conn_is_ordinary(conn) && + !kdbus_conn_is_monitor(conn) && + !kdbus_conn_is_activator(conn)) { + ret = -EOPNOTSUPP; + goto exit; + } + + ret = kdbus_sanitize_attach_flags(*item_attach_recv, + &attach_recv); + if (ret < 0) + goto exit; + } + + if (item_policy && !kdbus_conn_is_policy_holder(conn)) { + ret = -EOPNOTSUPP; + goto exit; + } + + /* now that we verified the input, update the connection */ + + if (item_policy) { + ret = kdbus_policy_set(&conn->ep->bus->policy_db, cmd->items, + KDBUS_ITEMS_SIZE(cmd, items), + 1, true, conn); + if (ret < 0) + goto exit; + } + + if (item_attach_send) + atomic64_set(&conn->attach_flags_send, attach_send); + + if (item_attach_recv) + atomic64_set(&conn->attach_flags_recv, attach_recv); + +exit: + return kdbus_args_clear(&args, ret); +} + +/** + * kdbus_cmd_send() - handle KDBUS_CMD_SEND + * @conn: connection to operate on + * @f: file this command was called on + * @argp: command payload + * + * Return: 0 on success, negative error code on failure. + */ +int kdbus_cmd_send(struct kdbus_conn *conn, struct file *f, void __user *argp) +{ + struct kdbus_cmd_send *cmd; + struct kdbus_kmsg *kmsg = NULL; + struct file *cancel_fd = NULL; + int ret; + + struct kdbus_arg argv[] = { + { .type = KDBUS_ITEM_NEGOTIATE }, + { .type = KDBUS_ITEM_CANCEL_FD }, + }; + struct kdbus_args args = { + .allowed_flags = KDBUS_FLAG_NEGOTIATE | + KDBUS_SEND_SYNC_REPLY, + .argv = argv, + .argc = ARRAY_SIZE(argv), + }; + + if (!kdbus_conn_is_ordinary(conn)) + return -EOPNOTSUPP; + + ret = kdbus_args_parse(&args, argp, &cmd); + if (ret != 0) + return ret; + + cmd->reply.return_flags = 0; + kdbus_pool_publish_empty(conn->pool, &cmd->reply.offset, + &cmd->reply.msg_size); + + if (argv[1].item) { + cancel_fd = fget(argv[1].item->fds[0]); + if (IS_ERR(cancel_fd)) { + ret = PTR_ERR(cancel_fd); + cancel_fd = NULL; + goto exit; + } + + if (!cancel_fd->f_op->poll) { + ret = -EINVAL; + goto exit; + } + } + + kmsg = kdbus_kmsg_new_from_cmd(conn, cmd); + if (IS_ERR(kmsg)) { + ret = PTR_ERR(kmsg); + kmsg = NULL; + goto exit; + } + + if (kmsg->msg.dst_id == KDBUS_DST_ID_BROADCAST) { + down_read(&conn->ep->bus->name_registry->rwlock); + kdbus_bus_broadcast(conn->ep->bus, conn, kmsg); + up_read(&conn->ep->bus->name_registry->rwlock); + } else if (cmd->flags & KDBUS_SEND_SYNC_REPLY) { + struct kdbus_reply *r; + ktime_t exp; + + exp = ns_to_ktime(kmsg->msg.timeout_ns); + r = kdbus_conn_call(conn, kmsg, exp); + if (IS_ERR(r)) { + ret = PTR_ERR(r); + goto exit; + } + + ret = kdbus_conn_wait_reply(conn, cmd, f, cancel_fd, r, exp); + kdbus_reply_unref(r); + if (ret < 0) + goto exit; + } else if ((kmsg->msg.flags & KDBUS_MSG_EXPECT_REPLY) || + kmsg->msg.cookie_reply == 0) { + ret = kdbus_conn_unicast(conn, kmsg); + if (ret < 0) + goto exit; + } else { + ret = kdbus_conn_reply(conn, kmsg); + if (ret < 0) + goto exit; + } + + if (kdbus_member_set_user(&cmd->reply, argp, typeof(*cmd), reply)) + ret = -EFAULT; + +exit: + if (cancel_fd) + fput(cancel_fd); + kdbus_kmsg_free(kmsg); + return kdbus_args_clear(&args, ret); +} + +/** + * kdbus_cmd_recv() - handle KDBUS_CMD_RECV + * @conn: connection to operate on + * @argp: command payload + * + * Return: 0 on success, negative error code on failure. + */ +int kdbus_cmd_recv(struct kdbus_conn *conn, void __user *argp) +{ + struct kdbus_queue_entry *entry; + struct kdbus_cmd_recv *cmd; + int ret; + + struct kdbus_arg argv[] = { + { .type = KDBUS_ITEM_NEGOTIATE }, + }; + struct kdbus_args args = { + .allowed_flags = KDBUS_FLAG_NEGOTIATE | + KDBUS_RECV_PEEK | + KDBUS_RECV_DROP | + KDBUS_RECV_USE_PRIORITY, + .argv = argv, + .argc = ARRAY_SIZE(argv), + }; + + if (!kdbus_conn_is_ordinary(conn) && + !kdbus_conn_is_monitor(conn) && + !kdbus_conn_is_activator(conn)) + return -EOPNOTSUPP; + + ret = kdbus_args_parse(&args, argp, &cmd); + if (ret != 0) + return ret; + + cmd->dropped_msgs = 0; + cmd->msg.return_flags = 0; + kdbus_pool_publish_empty(conn->pool, &cmd->msg.offset, + &cmd->msg.msg_size); + + /* DROP+priority is not realiably, so prevent it */ + if ((cmd->flags & KDBUS_RECV_DROP) && + (cmd->flags & KDBUS_RECV_USE_PRIORITY)) { + ret = -EINVAL; + goto exit; + } + + mutex_lock(&conn->lock); + + entry = kdbus_queue_peek(&conn->queue, cmd->priority, + cmd->flags & KDBUS_RECV_USE_PRIORITY); + if (!entry) { + mutex_unlock(&conn->lock); + ret = -EAGAIN; + } else if (cmd->flags & KDBUS_RECV_DROP) { + struct kdbus_reply *reply = kdbus_reply_ref(entry->reply); + + kdbus_queue_entry_free(entry); + + mutex_unlock(&conn->lock); + + if (reply) { + mutex_lock(&reply->reply_dst->lock); + if (!list_empty(&reply->entry)) { + kdbus_reply_unlink(reply); + if (reply->sync) + kdbus_sync_reply_wakeup(reply, -EPIPE); + else + kdbus_notify_reply_dead(conn->ep->bus, + reply->reply_dst->id, + reply->cookie); + } + mutex_unlock(&reply->reply_dst->lock); + kdbus_notify_flush(conn->ep->bus); + } + + kdbus_reply_unref(reply); + } else { + bool install_fds; + + /* + * PEEK just returns the location of the next message. Do not + * install FDs nor memfds nor anything else. The only + * information of interest should be the message header and + * metadata. Any FD numbers in the payload is undefined for + * PEEK'ed messages. + * Also make sure to never install fds into a connection that + * has refused to receive any. Ordinary connections will not get + * messages with FDs queued (the receiver will get -ECOMM), but + * eavesdroppers might. + */ + install_fds = (conn->flags & KDBUS_HELLO_ACCEPT_FD) && + !(cmd->flags & KDBUS_RECV_PEEK); + + ret = kdbus_queue_entry_install(entry, + &cmd->msg.return_flags, + install_fds); + if (ret < 0) { + mutex_unlock(&conn->lock); + goto exit; + } + + kdbus_pool_slice_publish(entry->slice, &cmd->msg.offset, + &cmd->msg.msg_size); + + if (!(cmd->flags & KDBUS_RECV_PEEK)) + kdbus_queue_entry_free(entry); + + mutex_unlock(&conn->lock); + } + + cmd->dropped_msgs = atomic_xchg(&conn->lost_count, 0); + if (cmd->dropped_msgs > 0) + cmd->return_flags |= KDBUS_RECV_RETURN_DROPPED_MSGS; + + if (kdbus_member_set_user(&cmd->msg, argp, typeof(*cmd), msg) || + kdbus_member_set_user(&cmd->dropped_msgs, argp, typeof(*cmd), + dropped_msgs)) + ret = -EFAULT; + +exit: + return kdbus_args_clear(&args, ret); +} + +/** + * kdbus_cmd_free() - handle KDBUS_CMD_FREE + * @conn: connection to operate on + * @argp: command payload + * + * Return: 0 on success, negative error code on failure. + */ +int kdbus_cmd_free(struct kdbus_conn *conn, void __user *argp) +{ + struct kdbus_cmd_free *cmd; + int ret; + + struct kdbus_arg argv[] = { + { .type = KDBUS_ITEM_NEGOTIATE }, + }; + struct kdbus_args args = { + .allowed_flags = KDBUS_FLAG_NEGOTIATE, + .argv = argv, + .argc = ARRAY_SIZE(argv), + }; + + if (!kdbus_conn_is_ordinary(conn) && + !kdbus_conn_is_monitor(conn) && + !kdbus_conn_is_activator(conn)) + return -EOPNOTSUPP; + + ret = kdbus_args_parse(&args, argp, &cmd); + if (ret != 0) + return ret; + + ret = kdbus_pool_release_offset(conn->pool, cmd->offset); + + return kdbus_args_clear(&args, ret); +} diff --git a/ipc/kdbus/connection.h b/ipc/kdbus/connection.h new file mode 100644 index 00000000000..d1ffe909cb3 --- /dev/null +++ b/ipc/kdbus/connection.h @@ -0,0 +1,257 @@ +/* + * 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 + * + * 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_CONNECTION_H +#define __KDBUS_CONNECTION_H + +#include <linux/atomic.h> +#include <linux/kref.h> +#include <linux/lockdep.h> +#include <linux/path.h> + +#include "limits.h" +#include "metadata.h" +#include "pool.h" +#include "queue.h" +#include "util.h" + +#define KDBUS_HELLO_SPECIAL_CONN (KDBUS_HELLO_ACTIVATOR | \ + KDBUS_HELLO_POLICY_HOLDER | \ + KDBUS_HELLO_MONITOR) + +struct kdbus_quota; +struct kdbus_kmsg; + +/** + * struct kdbus_conn - connection to a bus + * @kref: Reference count + * @active: Active references to the connection + * @id: Connection ID + * @flags: KDBUS_HELLO_* flags + * @attach_flags_send: KDBUS_ATTACH_* flags for sending + * @attach_flags_recv: KDBUS_ATTACH_* flags for receiving + * @description: Human-readable connection description, used for + * debugging. This field is only set when the + * connection is created. + * @ep: The endpoint this connection belongs to + * @lock: Connection data lock + * @hentry: Entry in ID <-> connection map + * @ep_entry: Entry in endpoint + * @monitor_entry: Entry in monitor, if the connection is a monitor + * @reply_list: List of connections this connection should + * reply to + * @work: Delayed work to handle timeouts + * activator for + * @match_db: Subscription filter to broadcast messages + * @meta: Active connection creator's metadata/credentials, + * either from the handle or from HELLO + * @pool: The user's buffer to receive messages + * @user: Owner of the connection + * @cred: The credentials of the connection at creation time + * @name_count: Number of owned well-known names + * @request_count: Number of pending requests issued by this + * connection that are waiting for replies from + * other peers + * @lost_count: Number of lost broadcast messages + * @wait: Wake up this endpoint + * @queue: The message queue associated with this connection + * @quota: Array of per-user quota indexed by user->id + * @n_quota: Number of elements in quota array + * @activator_of: Well-known name entry this connection acts as an + * @names_list: List of well-known names + * @names_queue_list: Well-known names this connection waits for + * @privileged: Whether this connection is privileged on the bus + * @faked_meta: Whether the metadata was faked on HELLO + */ +struct kdbus_conn { + struct kref kref; + atomic_t active; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif + u64 id; + u64 flags; + atomic64_t attach_flags_send; + atomic64_t attach_flags_recv; + const char *description; + struct kdbus_ep *ep; + struct mutex lock; + struct hlist_node hentry; + struct list_head ep_entry; + struct list_head monitor_entry; + struct list_head reply_list; + struct delayed_work work; + struct kdbus_match_db *match_db; + struct kdbus_meta_proc *meta; + struct kdbus_pool *pool; + struct kdbus_user *user; + const struct cred *cred; + atomic_t name_count; + atomic_t request_count; + atomic_t lost_count; + wait_queue_head_t wait; + struct kdbus_queue queue; + + struct kdbus_quota *quota; + unsigned int n_quota; + + /* protected by registry->rwlock */ + struct kdbus_name_entry *activator_of; + struct list_head names_list; + struct list_head names_queue_list; + + bool privileged:1; + bool faked_meta:1; +}; + +struct kdbus_conn *kdbus_conn_ref(struct kdbus_conn *conn); +struct kdbus_conn *kdbus_conn_unref(struct kdbus_conn *conn); +bool kdbus_conn_active(const struct kdbus_conn *conn); +int kdbus_conn_acquire(struct kdbus_conn *conn); +void kdbus_conn_release(struct kdbus_conn *conn); +int kdbus_conn_disconnect(struct kdbus_conn *conn, bool ensure_queue_empty); +bool kdbus_conn_has_name(struct kdbus_conn *conn, const char *name); +int kdbus_conn_quota_inc(struct kdbus_conn *c, struct kdbus_user *u, + size_t memory, size_t fds); +void kdbus_conn_quota_dec(struct kdbus_conn *c, struct kdbus_user *u, + size_t memory, size_t fds); +void kdbus_conn_lost_message(struct kdbus_conn *c); +int kdbus_conn_entry_insert(struct kdbus_conn *conn_src, + struct kdbus_conn *conn_dst, + const struct kdbus_kmsg *kmsg, + struct kdbus_reply *reply); +void kdbus_conn_move_messages(struct kdbus_conn *conn_dst, + struct kdbus_conn *conn_src, + u64 name_id); + +/* policy */ +bool kdbus_conn_policy_own_name(struct kdbus_conn *conn, + const struct cred *conn_creds, + const char *name); +bool kdbus_conn_policy_talk(struct kdbus_conn *conn, + const struct cred *conn_creds, + struct kdbus_conn *to); +bool kdbus_conn_policy_see_name_unlocked(struct kdbus_conn *conn, + const struct cred *curr_creds, + const char *name); +bool kdbus_conn_policy_see_notification(struct kdbus_conn *conn, + const struct cred *curr_creds, + const struct kdbus_kmsg *kmsg); + +/* command dispatcher */ +struct kdbus_conn *kdbus_cmd_hello(struct kdbus_ep *ep, bool privileged, + void __user *argp); +int kdbus_cmd_byebye_unlocked(struct kdbus_conn *conn, void __user *argp); +int kdbus_cmd_conn_info(struct kdbus_conn *conn, void __user *argp); +int kdbus_cmd_update(struct kdbus_conn *conn, void __user *argp); +int kdbus_cmd_send(struct kdbus_conn *conn, struct file *f, void __user *argp); +int kdbus_cmd_recv(struct kdbus_conn *conn, void __user *argp); +int kdbus_cmd_free(struct kdbus_conn *conn, void __user *argp); + +/** + * kdbus_conn_is_ordinary() - Check if connection is ordinary + * @conn: The connection to check + * + * Return: Non-zero if the connection is an ordinary connection + */ +static inline int kdbus_conn_is_ordinary(const struct kdbus_conn *conn) +{ + return !(conn->flags & KDBUS_HELLO_SPECIAL_CONN); +} + +/** + * kdbus_conn_is_activator() - Check if connection is an activator + * @conn: The connection to check + * + * Return: Non-zero if the connection is an activator + */ +static inline int kdbus_conn_is_activator(const struct kdbus_conn *conn) +{ + return conn->flags & KDBUS_HELLO_ACTIVATOR; +} + +/** + * kdbus_conn_is_policy_holder() - Check if connection is a policy holder + * @conn: The connection to check + * + * Return: Non-zero if the connection is a policy holder + */ +static inline int kdbus_conn_is_policy_holder(const struct kdbus_conn *conn) +{ + return conn->flags & KDBUS_HELLO_POLICY_HOLDER; +} + +/** + * kdbus_conn_is_monitor() - Check if connection is a monitor + * @conn: The connection to check + * + * Return: Non-zero if the connection is a monitor + */ +static inline int kdbus_conn_is_monitor(const struct kdbus_conn *conn) +{ + return conn->flags & KDBUS_HELLO_MONITOR; +} + +/** + * kdbus_conn_lock2() - Lock two connections + * @a: connection A to lock or NULL + * @b: connection B to lock or NULL + * + * Lock two connections at once. As we need to have a stable locking order, we + * always lock the connection with lower memory address first. + */ +static inline void kdbus_conn_lock2(struct kdbus_conn *a, struct kdbus_conn *b) +{ + if (a < b) { + if (a) + mutex_lock(&a->lock); + if (b && b != a) + mutex_lock_nested(&b->lock, !!a); + } else { + if (b) + mutex_lock(&b->lock); + if (a && a != b) + mutex_lock_nested(&a->lock, !!b); + } +} + +/** + * kdbus_conn_unlock2() - Unlock two connections + * @a: connection A to unlock or NULL + * @b: connection B to unlock or NULL + * + * Unlock two connections at once. See kdbus_conn_lock2(). + */ +static inline void kdbus_conn_unlock2(struct kdbus_conn *a, + struct kdbus_conn *b) +{ + if (a) + mutex_unlock(&a->lock); + if (b && b != a) + mutex_unlock(&b->lock); +} + +/** + * kdbus_conn_assert_active() - lockdep assert on active lock + * @conn: connection that shall be active + * + * This verifies via lockdep that the caller holds an active reference to the + * given connection. + */ +static inline void kdbus_conn_assert_active(struct kdbus_conn *conn) +{ + lockdep_assert_held(conn); +} + +#endif diff --git a/ipc/kdbus/item.c b/ipc/kdbus/item.c new file mode 100644 index 00000000000..745ad549509 --- /dev/null +++ b/ipc/kdbus/item.c @@ -0,0 +1,339 @@ +/* + * 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/ctype.h> +#include <linux/fs.h> +#include <linux/string.h> + +#include "item.h" +#include "limits.h" +#include "util.h" + +/* + * This verifies the string at position @str with size @size is properly + * zero-terminated and does not contain a 0-byte but at the end. + */ +static bool kdbus_str_valid(const char *str, size_t size) +{ + return size > 0 && memchr(str, '\0', size) == str + size - 1; +} + +/** + * kdbus_item_validate_name() - validate an item containing a name + * @item: Item to validate + * + * Return: zero on success or an negative error code on failure + */ +int kdbus_item_validate_name(const struct kdbus_item *item) +{ + const char *name = item->str; + unsigned int i; + size_t len; + + if (item->size < KDBUS_ITEM_HEADER_SIZE + 2) + return -EINVAL; + + if (item->size > KDBUS_ITEM_HEADER_SIZE + + KDBUS_SYSNAME_MAX_LEN + 1) + return -ENAMETOOLONG; + + if (!kdbus_str_valid(name, KDBUS_ITEM_PAYLOAD_SIZE(item))) + return -EINVAL; + + len = strlen(name); + if (len == 0) + return -EINVAL; + + for (i = 0; i < len; i++) { + if (isalpha(name[i])) + continue; + if (isdigit(name[i])) + continue; + if (name[i] == '_') + continue; + if (i > 0 && i + 1 < len && (name[i] == '-' || name[i] == '.')) + continue; + + return -EINVAL; + } + + return 0; +} + +/** + * kdbus_item_validate() - validate a single item + * @item: item to validate + * + * Return: 0 if item is valid, negative error code if not. + */ +int kdbus_item_validate(const struct kdbus_item *item) +{ + size_t payload_size = KDBUS_ITEM_PAYLOAD_SIZE(item); + size_t l; + int ret; + + BUILD_BUG_ON(KDBUS_ITEM_HEADER_SIZE != + sizeof(struct kdbus_item_header)); + + if (item->size < KDBUS_ITEM_HEADER_SIZE) + return -EINVAL; + + switch (item->type) { + case KDBUS_ITEM_NEGOTIATE: + if (payload_size % sizeof(u64) != 0) + return -EINVAL; + break; + + case KDBUS_ITEM_PAYLOAD_VEC: + if (payload_size != sizeof(struct kdbus_vec)) + return -EINVAL; + if (item->vec.size == 0 || item->vec.size > SIZE_MAX) + return -EINVAL; + break; + + case KDBUS_ITEM_PAYLOAD_OFF: + if (payload_size != sizeof(struct kdbus_vec)) + return -EINVAL; + if (item->vec.size == 0 || item->vec.size > SIZE_MAX) + return -EINVAL; + break; + + case KDBUS_ITEM_PAYLOAD_MEMFD: + if (payload_size != sizeof(struct kdbus_memfd)) + return -EINVAL; + if (item->memfd.size == 0 || item->memfd.size > SIZE_MAX) + return -EINVAL; + if (item->memfd.fd < 0) + return -EBADF; + break; + + case KDBUS_ITEM_FDS: + if (payload_size % sizeof(int) != 0) + return -EINVAL; + break; + + case KDBUS_ITEM_CANCEL_FD: + if (payload_size != sizeof(int)) + return -EINVAL; + break; + + case KDBUS_ITEM_BLOOM_PARAMETER: + if (payload_size != sizeof(struct kdbus_bloom_parameter)) + return -EINVAL; + break; + + case KDBUS_ITEM_BLOOM_FILTER: + /* followed by the bloom-mask, depends on the bloom-size */ + if (payload_size < sizeof(struct kdbus_bloom_filter)) + return -EINVAL; + break; + + case KDBUS_ITEM_BLOOM_MASK: + /* size depends on bloom-size of bus */ + break; + + case KDBUS_ITEM_CONN_DESCRIPTION: + case KDBUS_ITEM_MAKE_NAME: + ret = kdbus_item_validate_name(item); + if (ret < 0) + return ret; + break; + + case KDBUS_ITEM_ATTACH_FLAGS_SEND: + case KDBUS_ITEM_ATTACH_FLAGS_RECV: + case KDBUS_ITEM_ID: + if (payload_size != sizeof(u64)) + return -EINVAL; + break; + + case KDBUS_ITEM_TIMESTAMP: + if (payload_size != sizeof(struct kdbus_timestamp)) + return -EINVAL; + break; + + case KDBUS_ITEM_CREDS: + if (payload_size != sizeof(struct kdbus_creds)) + return -EINVAL; + break; + + case KDBUS_ITEM_AUXGROUPS: + if (payload_size % sizeof(u32) != 0) + return -EINVAL; + break; + + case KDBUS_ITEM_NAME: + case KDBUS_ITEM_DST_NAME: + case KDBUS_ITEM_PID_COMM: + case KDBUS_ITEM_TID_COMM: + case KDBUS_ITEM_EXE: + case KDBUS_ITEM_CMDLINE: + case KDBUS_ITEM_CGROUP: + case KDBUS_ITEM_SECLABEL: + if (!kdbus_str_valid(item->str, payload_size)) + return -EINVAL; + break; + + case KDBUS_ITEM_CAPS: + if (payload_size < sizeof(u32)) + return -EINVAL; + if (payload_size < sizeof(u32) + + 4 * CAP_TO_INDEX(item->caps.last_cap) * sizeof(u32)) + return -EINVAL; + break; + + case KDBUS_ITEM_AUDIT: + if (payload_size != sizeof(struct kdbus_audit)) + return -EINVAL; + break; + + case KDBUS_ITEM_POLICY_ACCESS: + if (payload_size != sizeof(struct kdbus_policy_access)) + return -EINVAL; + break; + + case KDBUS_ITEM_NAME_ADD: + case KDBUS_ITEM_NAME_REMOVE: + case KDBUS_ITEM_NAME_CHANGE: + if (payload_size < sizeof(struct kdbus_notify_name_change)) + return -EINVAL; + l = payload_size - offsetof(struct kdbus_notify_name_change, + name); + if (l > 0 && !kdbus_str_valid(item->name_change.name, l)) + return -EINVAL; + break; + + case KDBUS_ITEM_ID_ADD: + case KDBUS_ITEM_ID_REMOVE: + if (payload_size != sizeof(struct kdbus_notify_id_change)) + return -EINVAL; + break; + + case KDBUS_ITEM_REPLY_TIMEOUT: + case KDBUS_ITEM_REPLY_DEAD: + if (payload_size != 0) + return -EINVAL; + break; + + default: + break; + } + + return 0; +} + +/** + * kdbus_items_validate() - validate items passed by user-space + * @items: items to validate + * @items_size: number of items + * + * This verifies that the passed items pointer is consistent and valid. + * Furthermore, each item is checked for: + * - valid "size" value + * - payload is of expected type + * - payload is fully included in the item + * - string payloads are zero-terminated + * + * Return: 0 on success, negative error code on failure. + */ +int kdbus_items_validate(const struct kdbus_item *items, size_t items_size) +{ + const struct kdbus_item *item; + int ret; + + KDBUS_ITEMS_FOREACH(item, items, items_size) { + if (!KDBUS_ITEM_VALID(item, items, items_size)) + return -EINVAL; + + ret = kdbus_item_validate(item); + if (ret < 0) + return ret; + } + + if (!KDBUS_ITEMS_END(item, items, items_size)) + return -EINVAL; + + return 0; +} + +static struct kdbus_item *kdbus_items_get(const struct kdbus_item *items, + size_t items_size, + unsigned int item_type) +{ + const struct kdbus_item *iter, *found = NULL; + + KDBUS_ITEMS_FOREACH(iter, items, items_size) { + if (iter->type == item_type) { + if (found) + return ERR_PTR(-EEXIST); + found = iter; + } + } + + return (struct kdbus_item *)found ? : ERR_PTR(-EBADMSG); +} + +/** + * kdbus_items_get_str() - get string from a list of items + * @items: The items to walk + * @items_size: The size of all items + * @item_type: The item type to look for + * + * This function walks a list of items and searches for items of type + * @item_type. If it finds exactly one such item, @str_ret will be set to + * the .str member of the item. + * + * Return: the string, if the item was found exactly once, ERR_PTR(-EEXIST) + * if the item was found more than once, and ERR_PTR(-EBADMSG) if there was + * no item of the given type. + */ +const char *kdbus_items_get_str(const struct kdbus_item *items, + size_t items_size, + unsigned int item_type) +{ + const struct kdbus_item *item; + + item = kdbus_items_get(items, items_size, item_type); + return IS_ERR(item) ? ERR_CAST(item) : item->str; +} + +/** + * kdbus_item_set() - Set item content + * @item: The item to modify + * @type: The item type to set (KDBUS_ITEM_*) + * @data: Data to copy to item->data, may be %NULL + * @len: Number of bytes in @data + * + * This sets type, size and data fields of an item. If @data is NULL, the data + * memory is cleared. + * + * Note that you must align your @data memory to 8 bytes. Trailing padding (in + * case @len is not 8byte aligned) is cleared by this call. + * + * Returns: Pointer to the following item. + */ +struct kdbus_item *kdbus_item_set(struct kdbus_item *item, u64 type, + const void *data, size_t len) +{ + item->type = type; + item->size = KDBUS_ITEM_HEADER_SIZE + len; + + if (data) { + memcpy(item->data, data, len); + memset(item->data + len, 0, KDBUS_ALIGN8(len) - len); + } else { + memset(item->data, 0, KDBUS_ALIGN8(len)); + } + + return KDBUS_ITEM_NEXT(item); +} diff --git a/ipc/kdbus/item.h b/ipc/kdbus/item.h new file mode 100644 index 00000000000..eeefd8beac3 --- /dev/null +++ b/ipc/kdbus/item.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 + * 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_ITEM_H +#define __KDBUS_ITEM_H + +#include <linux/kernel.h> +#include <uapi/linux/kdbus.h> + +#include "util.h" + +/* generic access and iterators over a stream of items */ +#define KDBUS_ITEM_NEXT(_i) (typeof(_i))(((u8 *)_i) + KDBUS_ALIGN8((_i)->size)) +#define KDBUS_ITEMS_SIZE(_h, _is) ((_h)->size - offsetof(typeof(*_h), _is)) +#define KDBUS_ITEM_HEADER_SIZE offsetof(struct kdbus_item, data) +#define KDBUS_ITEM_SIZE(_s) KDBUS_ALIGN8(KDBUS_ITEM_HEADER_SIZE + (_s)) +#define KDBUS_ITEM_PAYLOAD_SIZE(_i) ((_i)->size - KDBUS_ITEM_HEADER_SIZE) + +#define KDBUS_ITEMS_FOREACH(_i, _is, _s) \ + for (_i = _is; \ + ((u8 *)(_i) < (u8 *)(_is) + (_s)) && \ + ((u8 *)(_i) >= (u8 *)(_is)); \ + _i = KDBUS_ITEM_NEXT(_i)) + +#define KDBUS_ITEM_VALID(_i, _is, _s) \ + ((_i)->size >= KDBUS_ITEM_HEADER_SIZE && \ + (u8 *)(_i) + (_i)->size > (u8 *)(_i) && \ + (u8 *)(_i) + (_i)->size <= (u8 *)(_is) + (_s) && \ + (u8 *)(_i) >= (u8 *)(_is)) + +#define KDBUS_ITEMS_END(_i, _is, _s) \ + ((u8 *)_i == ((u8 *)(_is) + KDBUS_ALIGN8(_s))) + +/** + * struct kdbus_item_header - Describes the fix part of an item + * @size: The total size of the item + * @type: The item type, one of KDBUS_ITEM_* + */ +struct kdbus_item_header { + u64 size; + u64 type; +}; + +int kdbus_item_validate_name(const struct kdbus_item *item); +int kdbus_item_validate(const struct kdbus_item *item); +int kdbus_items_validate(const struct kdbus_item *items, size_t items_size); +const char *kdbus_items_get_str(const struct kdbus_item *items, + size_t items_size, + unsigned int item_type); +struct kdbus_item *kdbus_item_set(struct kdbus_item *item, u64 type, + const void *data, size_t len); + +#endif diff --git a/ipc/kdbus/message.c b/ipc/kdbus/message.c new file mode 100644 index 00000000000..80960756a32 --- /dev/null +++ b/ipc/kdbus/message.c @@ -0,0 +1,616 @@ +/* + * 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/cgroup.h> +#include <linux/cred.h> +#include <linux/file.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/sched.h> +#include <linux/shmem_fs.h> +#include <linux/sizes.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <net/sock.h> + +#include "bus.h" +#include "connection.h" +#include "domain.h" +#include "endpoint.h" +#include "handle.h" +#include "item.h" +#include "match.h" +#include "message.h" +#include "names.h" +#include "policy.h" + +#define KDBUS_KMSG_HEADER_SIZE offsetof(struct kdbus_kmsg, msg) + +static struct kdbus_msg_resources *kdbus_msg_resources_new(void) +{ + struct kdbus_msg_resources *r; + + r = kzalloc(sizeof(*r), GFP_KERNEL); + if (!r) + return ERR_PTR(-ENOMEM); + + kref_init(&r->kref); + + return r; +} + +static void __kdbus_msg_resources_free(struct kref *kref) +{ + struct kdbus_msg_resources *r = + container_of(kref, struct kdbus_msg_resources, kref); + size_t i; + + for (i = 0; i < r->data_count; ++i) { + switch (r->data[i].type) { + case KDBUS_MSG_DATA_VEC: + /* nothing to do */ + break; + case KDBUS_MSG_DATA_MEMFD: + if (r->data[i].memfd.file) + fput(r->data[i].memfd.file); + break; + } + } + + for (i = 0; i < r->fds_count; i++) + if (r->fds[i]) + fput(r->fds[i]); + + kfree(r->dst_name); + kfree(r->data); + kfree(r->fds); + kfree(r); +} + +/** + * kdbus_msg_resources_ref() - Acquire reference to msg resources + * @r: resources to acquire ref to + * + * Return: The acquired resource + */ +struct kdbus_msg_resources * +kdbus_msg_resources_ref(struct kdbus_msg_resources *r) +{ + if (r) + kref_get(&r->kref); + return r; +} + +/** + * kdbus_msg_resources_unref() - Drop reference to msg resources + * @r: resources to drop reference of + * + * Return: NULL + */ +struct kdbus_msg_resources * +kdbus_msg_resources_unref(struct kdbus_msg_resources *r) +{ + if (r) + kref_put(&r->kref, __kdbus_msg_resources_free); + return NULL; +} + +/** + * kdbus_kmsg_free() - free allocated message + * @kmsg: Message + */ +void kdbus_kmsg_free(struct kdbus_kmsg *kmsg) +{ + if (!kmsg) + return; + + kdbus_msg_resources_unref(kmsg->res); + kdbus_meta_conn_unref(kmsg->conn_meta); + kdbus_meta_proc_unref(kmsg->proc_meta); + kfree(kmsg->iov); + kfree(kmsg); +} + +/** + * kdbus_kmsg_new() - allocate message + * @bus: Bus this message is allocated on + * @extra_size: Additional size to reserve for data + * + * Return: new kdbus_kmsg on success, ERR_PTR on failure. + */ +struct kdbus_kmsg *kdbus_kmsg_new(struct kdbus_bus *bus, size_t extra_size) +{ + struct kdbus_kmsg *m; + size_t size; + int ret; + + size = sizeof(struct kdbus_kmsg) + KDBUS_ITEM_SIZE(extra_size); + m = kzalloc(size, GFP_KERNEL); + if (!m) + return ERR_PTR(-ENOMEM); + + m->seq = atomic64_inc_return(&bus->domain->last_id); + m->msg.size = size - KDBUS_KMSG_HEADER_SIZE; + m->msg.items[0].size = KDBUS_ITEM_SIZE(extra_size); + + m->proc_meta = kdbus_meta_proc_new(); + if (IS_ERR(m->proc_meta)) { + ret = PTR_ERR(m->proc_meta); + m->proc_meta = NULL; + goto exit; + } + + m->conn_meta = kdbus_meta_conn_new(); + if (IS_ERR(m->conn_meta)) { + ret = PTR_ERR(m->conn_meta); + m->conn_meta = NULL; + goto exit; + } + + return m; + +exit: + kdbus_kmsg_free(m); + return ERR_PTR(ret); +} + +static int kdbus_handle_check_file(struct file *file) +{ + struct inode *inode = file_inode(file); + struct socket *sock; + + /* + * Don't allow file descriptors in the transport that themselves allow + * file descriptor queueing. This will eventually be allowed once both + * unix domain sockets and kdbus share a generic garbage collector. + */ + + if (file->f_op == &kdbus_handle_ops) + return -EOPNOTSUPP; + + if (!S_ISSOCK(inode->i_mode)) + return 0; + + if (file->f_mode & FMODE_PATH) + return 0; + + sock = SOCKET_I(inode); + if (sock->sk && sock->ops && sock->ops->family == PF_UNIX) + return -EOPNOTSUPP; + + return 0; +} + +static const char * const zeros = "\0\0\0\0\0\0\0"; + +/* + * kdbus_msg_scan_items() - validate incoming data and prepare parsing + * @kmsg: Message + * @bus: Bus the message is sent over + * + * Return: 0 on success, negative errno on failure. + * + * Files references in MEMFD or FDS items are pinned. + * + * On errors, the caller should drop any taken reference with + * kdbus_kmsg_free() + */ +static int kdbus_msg_scan_items(struct kdbus_kmsg *kmsg, + struct kdbus_bus *bus) +{ + struct kdbus_msg_resources *res = kmsg->res; + const struct kdbus_msg *msg = &kmsg->msg; + const struct kdbus_item *item; + size_t n, n_vecs, n_memfds; + bool has_bloom = false; + bool has_name = false; + bool has_fds = false; + bool is_broadcast; + bool is_signal; + u64 vec_size; + + is_broadcast = (msg->dst_id == KDBUS_DST_ID_BROADCAST); + is_signal = !!(msg->flags & KDBUS_MSG_SIGNAL); + + /* count data payloads */ + n_vecs = 0; + n_memfds = 0; + KDBUS_ITEMS_FOREACH(item, msg->items, KDBUS_ITEMS_SIZE(msg, items)) { + switch (item->type) { + case KDBUS_ITEM_PAYLOAD_VEC: + ++n_vecs; + break; + case KDBUS_ITEM_PAYLOAD_MEMFD: + ++n_memfds; + if (item->memfd.size % 8) + ++n_vecs; + break; + default: + break; + } + } + + n = n_vecs + n_memfds; + if (n > 0) { + res->data = kcalloc(n, sizeof(*res->data), GFP_KERNEL); + if (!res->data) + return -ENOMEM; + } + + if (n_vecs > 0) { + kmsg->iov = kcalloc(n_vecs, sizeof(*kmsg->iov), GFP_KERNEL); + if (!kmsg->iov) + return -ENOMEM; + } + + /* import data payloads */ + n = 0; + vec_size = 0; + KDBUS_ITEMS_FOREACH(item, msg->items, KDBUS_ITEMS_SIZE(msg, items)) { + size_t payload_size = KDBUS_ITEM_PAYLOAD_SIZE(item); + struct iovec *iov = kmsg->iov + kmsg->iov_count; + + if (++n > KDBUS_MSG_MAX_ITEMS) + return -E2BIG; + + switch (item->type) { + case KDBUS_ITEM_PAYLOAD_VEC: { + struct kdbus_msg_data *d = res->data + res->data_count; + void __force __user *ptr = KDBUS_PTR(item->vec.address); + size_t size = item->vec.size; + + if (vec_size + size < vec_size) + return -EMSGSIZE; + if (vec_size + size > KDBUS_MSG_MAX_PAYLOAD_VEC_SIZE) + return -EMSGSIZE; + + d->type = KDBUS_MSG_DATA_VEC; + d->size = size; + + if (ptr) { + if (unlikely(!access_ok(VERIFY_READ, ptr, + size))) + return -EFAULT; + + d->vec.off = kmsg->pool_size; + iov->iov_base = ptr; + iov->iov_len = size; + } else { + d->vec.off = ~0ULL; + iov->iov_base = (char __user *)zeros; + iov->iov_len = size % 8; + } + + if (kmsg->pool_size + iov->iov_len < kmsg->pool_size) + return -EMSGSIZE; + + kmsg->pool_size += iov->iov_len; + ++kmsg->iov_count; + ++res->vec_count; + ++res->data_count; + vec_size += size; + + break; + } + + case KDBUS_ITEM_PAYLOAD_MEMFD: { + struct kdbus_msg_data *d = res->data + res->data_count; + u64 start = item->memfd.start; + u64 size = item->memfd.size; + size_t pad = size % 8; + int seals, mask; + struct file *f; + + if (kmsg->pool_size + size % 8 < kmsg->pool_size) + return -EMSGSIZE; + if (start + size < start) + return -EMSGSIZE; + + if (item->memfd.fd < 0) + return -EBADF; + + if (res->memfd_count >= KDBUS_MSG_MAX_MEMFD_ITEMS) + return -E2BIG; + + f = fget(item->memfd.fd); + if (!f) + return -EBADF; + + if (pad) { + iov->iov_base = (char __user *)zeros; + iov->iov_len = pad; + + kmsg->pool_size += pad; + ++kmsg->iov_count; + } + + ++res->data_count; + ++res->memfd_count; + + d->type = KDBUS_MSG_DATA_MEMFD; + d->size = size; + d->memfd.start = start; + d->memfd.file = f; + + /* + * We only accept a sealed memfd file whose content + * cannot be altered by the sender or anybody else + * while it is shared or in-flight. Other files need + * to be passed with KDBUS_MSG_FDS. + */ + seals = shmem_get_seals(f); + if (seals < 0) + return -EMEDIUMTYPE; + + mask = F_SEAL_SHRINK | F_SEAL_GROW | + F_SEAL_WRITE | F_SEAL_SEAL; + if ((seals & mask) != mask) + return -ETXTBSY; + + if (start + size > (u64)i_size_read(file_inode(f))) + return -EBADF; + + break; + } + + case KDBUS_ITEM_FDS: { + unsigned int i; + unsigned int fds_count = payload_size / sizeof(int); + + /* do not allow multiple fd arrays */ + if (has_fds) + return -EEXIST; + has_fds = true; + + /* Do not allow to broadcast file descriptors */ + if (is_broadcast) + return -ENOTUNIQ; + + if (fds_count > KDBUS_CONN_MAX_FDS_PER_USER) + return -EMFILE; + + res->fds = kcalloc(fds_count, sizeof(struct file *), + GFP_KERNEL); + if (!res->fds) + return -ENOMEM; + + for (i = 0; i < fds_count; i++) { + int fd = item->fds[i]; + int ret; + + /* + * Verify the fd and increment the usage count. + * Use fget_raw() to allow passing O_PATH fds. + */ + if (fd < 0) + return -EBADF; + + res->fds[i] = fget_raw(fd); + if (!res->fds[i]) + return -EBADF; + + res->fds_count++; + + ret = kdbus_handle_check_file(res->fds[i]); + if (ret < 0) + return ret; + } + + break; + } + + case KDBUS_ITEM_BLOOM_FILTER: { + u64 bloom_size; + + /* do not allow multiple bloom filters */ + if (has_bloom) + return -EEXIST; + has_bloom = true; + + bloom_size = payload_size - + offsetof(struct kdbus_bloom_filter, data); + + /* + * Allow only bloom filter sizes of a multiple of 64bit. + */ + if (!KDBUS_IS_ALIGNED8(bloom_size)) + return -EFAULT; + + /* do not allow mismatching bloom filter sizes */ + if (bloom_size != bus->bloom.size) + return -EDOM; + + kmsg->bloom_filter = &item->bloom_filter; + break; + } + + case KDBUS_ITEM_DST_NAME: + /* do not allow multiple names */ + if (has_name) + return -EEXIST; + has_name = true; + + if (!kdbus_name_is_valid(item->str, false)) + return -EINVAL; + + res->dst_name = kstrdup(item->str, GFP_KERNEL); + if (!res->dst_name) + return -ENOMEM; + break; + + default: + return -EINVAL; + } + } + + /* name is needed if no ID is given */ + if (msg->dst_id == KDBUS_DST_ID_NAME && !has_name) + return -EDESTADDRREQ; + + if (is_broadcast) { + /* Broadcasts can't take names */ + if (has_name) + return -EBADMSG; + + /* All broadcasts have to be signals */ + if (!is_signal) + return -EBADMSG; + + /* Timeouts are not allowed for broadcasts */ + if (msg->timeout_ns > 0) + return -ENOTUNIQ; + } + + /* + * Signal messages require a bloom filter, and bloom filters are + * only valid with signals. + */ + if (is_signal ^ has_bloom) + return -EBADMSG; + + return 0; +} + +/** + * kdbus_kmsg_new_from_cmd() - create kernel message from send payload + * @conn: Connection + * @cmd_send: Payload of KDBUS_CMD_SEND + * + * Return: a new kdbus_kmsg on success, ERR_PTR on failure. + */ +struct kdbus_kmsg *kdbus_kmsg_new_from_cmd(struct kdbus_conn *conn, + struct kdbus_cmd_send *cmd_send) +{ + struct kdbus_kmsg *m; + u64 size; + int ret; + + ret = kdbus_copy_from_user(&size, KDBUS_PTR(cmd_send->msg_address), + sizeof(size)); + if (ret < 0) + return ERR_PTR(ret); + + if (size < sizeof(struct kdbus_msg) || size > KDBUS_MSG_MAX_SIZE) + return ERR_PTR(-EINVAL); + + m = kmalloc(size + KDBUS_KMSG_HEADER_SIZE, GFP_KERNEL); + if (!m) + return ERR_PTR(-ENOMEM); + + memset(m, 0, KDBUS_KMSG_HEADER_SIZE); + m->seq = atomic64_inc_return(&conn->ep->bus->domain->last_id); + + m->proc_meta = kdbus_meta_proc_new(); + if (IS_ERR(m->proc_meta)) { + ret = PTR_ERR(m->proc_meta); + m->proc_meta = NULL; + goto exit_free; + } + + m->conn_meta = kdbus_meta_conn_new(); + if (IS_ERR(m->conn_meta)) { + ret = PTR_ERR(m->conn_meta); + m->conn_meta = NULL; + goto exit_free; + } + + if (copy_from_user(&m->msg, KDBUS_PTR(cmd_send->msg_address), size)) { + ret = -EFAULT; + goto exit_free; + } + + if (m->msg.size != size) { + ret = -EINVAL; + goto exit_free; + } + + if (m->msg.flags & ~(KDBUS_MSG_EXPECT_REPLY | + KDBUS_MSG_NO_AUTO_START | + KDBUS_MSG_SIGNAL)) { + ret = -EINVAL; + goto exit_free; + } + + ret = kdbus_items_validate(m->msg.items, + KDBUS_ITEMS_SIZE(&m->msg, items)); + if (ret < 0) + goto exit_free; + + m->res = kdbus_msg_resources_new(); + if (IS_ERR(m->res)) { + ret = PTR_ERR(m->res); + m->res = NULL; + goto exit_free; + } + + /* do not accept kernel-generated messages */ + if (m->msg.payload_type == KDBUS_PAYLOAD_KERNEL) { + ret = -EINVAL; + goto exit_free; + } + + if (m->msg.flags & KDBUS_MSG_EXPECT_REPLY) { + /* requests for replies need timeout and cookie */ + if (m->msg.timeout_ns == 0 || m->msg.cookie == 0) { + ret = -EINVAL; + goto exit_free; + } + + /* replies may not be expected for broadcasts */ + if (m->msg.dst_id == KDBUS_DST_ID_BROADCAST) { + ret = -ENOTUNIQ; + goto exit_free; + } + + /* replies may not be expected for signals */ + if (m->msg.flags & KDBUS_MSG_SIGNAL) { + ret = -EINVAL; + goto exit_free; + } + } else { + /* + * KDBUS_SEND_SYNC_REPLY is only valid together with + * KDBUS_MSG_EXPECT_REPLY + */ + if (cmd_send->flags & KDBUS_SEND_SYNC_REPLY) { + ret = -EINVAL; + goto exit_free; + } + + /* replies cannot be signals */ + if (m->msg.cookie_reply && (m->msg.flags & KDBUS_MSG_SIGNAL)) { + ret = -EINVAL; + goto exit_free; + } + } + + ret = kdbus_msg_scan_items(m, conn->ep->bus); + if (ret < 0) + goto exit_free; + + /* patch-in the source of this message */ + if (m->msg.src_id > 0 && m->msg.src_id != conn->id) { + ret = -EINVAL; + goto exit_free; + } + m->msg.src_id = conn->id; + + return m; + +exit_free: + kdbus_kmsg_free(m); + return ERR_PTR(ret); +} diff --git a/ipc/kdbus/message.h b/ipc/kdbus/message.h new file mode 100644 index 00000000000..af477585023 --- /dev/null +++ b/ipc/kdbus/message.h @@ -0,0 +1,133 @@ +/* + * 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_MESSAGE_H +#define __KDBUS_MESSAGE_H + +#include "util.h" +#include "metadata.h" + +/** + * enum kdbus_msg_data_type - Type of kdbus_msg_data payloads + * @KDBUS_MSG_DATA_VEC: Data vector provided by user-space + * @KDBUS_MSG_DATA_MEMFD: Memfd payload + */ +enum kdbus_msg_data_type { + KDBUS_MSG_DATA_VEC, + KDBUS_MSG_DATA_MEMFD, +}; + +/** + * struct kdbus_msg_data - Data payload as stored by messages + * @type: Type of payload (KDBUS_MSG_DATA_*) + * @size: Size of the described payload + * @off: The offset, relative to the vec slice + * @start: Offset inside the memfd + * @file: Backing file referenced by the memfd + */ +struct kdbus_msg_data { + unsigned int type; + u64 size; + + union { + struct { + u64 off; + } vec; + struct { + u64 start; + struct file *file; + } memfd; + }; +}; + +/** + * struct kdbus_kmsg_resources - resources of a message + * @kref: Reference counter + * @dst_name: Short-cut to msg for faster lookup + * @fds: Array of file descriptors to pass + * @fds_count: Number of file descriptors to pass + * @data: Array of data payloads + * @vec_count: Number of VEC entries + * @memfd_count: Number of MEMFD entries in @data + * @data_count: Sum of @vec_count + @memfd_count + */ +struct kdbus_msg_resources { + struct kref kref; + const char *dst_name; + + struct file **fds; + unsigned int fds_count; + + struct kdbus_msg_data *data; + size_t vec_count; + size_t memfd_count; + size_t data_count; +}; + +struct kdbus_msg_resources * +kdbus_msg_resources_ref(struct kdbus_msg_resources *r); +struct kdbus_msg_resources * +kdbus_msg_resources_unref(struct kdbus_msg_resources *r); + +/** + * struct kdbus_kmsg - internal message handling data + * @seq: Domain-global message sequence number + * @notify_type: Short-cut for faster lookup + * @notify_old_id: Short-cut for faster lookup + * @notify_new_id: Short-cut for faster lookup + * @notify_name: Short-cut for faster lookup + * @dst_name_id: Short-cut to msg for faster lookup + * @bloom_filter: Bloom filter to match message properties + * @bloom_generation: Generation of bloom element set + * @notify_entry: List of kernel-generated notifications + * @iov: Array of iovec, describing the payload to copy + * @iov_count: Number of array members in @iov + * @pool_size: Overall size of inlined data referenced by @iov + * @proc_meta: Appended SCM-like metadata of the sending process + * @conn_meta: Appended SCM-like metadata of the sending connection + * @res: Message resources + * @msg: Message from or to userspace + */ +struct kdbus_kmsg { + u64 seq; + u64 notify_type; + u64 notify_old_id; + u64 notify_new_id; + const char *notify_name; + + u64 dst_name_id; + const struct kdbus_bloom_filter *bloom_filter; + u64 bloom_generation; + struct list_head notify_entry; + + struct iovec *iov; + size_t iov_count; + u64 pool_size; + + struct kdbus_meta_proc *proc_meta; + struct kdbus_meta_conn *conn_meta; + struct kdbus_msg_resources *res; + + /* variable size, must be the last member */ + struct kdbus_msg msg; +}; + +struct kdbus_bus; +struct kdbus_conn; + +struct kdbus_kmsg *kdbus_kmsg_new(struct kdbus_bus *bus, size_t extra_size); +struct kdbus_kmsg *kdbus_kmsg_new_from_cmd(struct kdbus_conn *conn, + struct kdbus_cmd_send *cmd_send); +void kdbus_kmsg_free(struct kdbus_kmsg *kmsg); + +#endif diff --git a/ipc/kdbus/queue.c b/ipc/kdbus/queue.c new file mode 100644 index 00000000000..a449464a397 --- /dev/null +++ b/ipc/kdbus/queue.c @@ -0,0 +1,678 @@ +/* + * 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/audit.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/hashtable.h> +#include <linux/idr.h> +#include <linux/init.h> +#include <linux/math64.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/poll.h> +#include <linux/sched.h> +#include <linux/sizes.h> +#include <linux/slab.h> +#include <linux/syscalls.h> +#include <linux/uio.h> + +#include "util.h" +#include "domain.h" +#include "connection.h" +#include "item.h" +#include "message.h" +#include "metadata.h" +#include "queue.h" +#include "reply.h" + +/** + * kdbus_queue_init() - initialize data structure related to a queue + * @queue: The queue to initialize + */ +void kdbus_queue_init(struct kdbus_queue *queue) +{ + INIT_LIST_HEAD(&queue->msg_list); + queue->msg_prio_queue = RB_ROOT; +} + +/** + * kdbus_queue_peek() - Retrieves an entry from a queue + * @queue: The queue + * @priority: The minimum priority of the entry to peek + * @use_priority: Boolean flag whether or not to peek by priority + * + * Look for a entry in a queue, either by priority, or the oldest one (FIFO). + * The entry is not freed, put off the queue's lists or anything else. + * + * Return: the peeked queue entry on success, NULL if no suitable msg is found + */ +struct kdbus_queue_entry *kdbus_queue_peek(struct kdbus_queue *queue, + s64 priority, bool use_priority) +{ + struct kdbus_queue_entry *e; + + if (list_empty(&queue->msg_list)) + return NULL; + + if (use_priority) { + /* get next entry with highest priority */ + e = rb_entry(queue->msg_prio_highest, + struct kdbus_queue_entry, prio_node); + + /* no entry with the requested priority */ + if (e->priority > priority) + return NULL; + } else { + /* ignore the priority, return the next entry in the entry */ + e = list_first_entry(&queue->msg_list, + struct kdbus_queue_entry, entry); + } + + return e; +} + +static void kdbus_queue_entry_link(struct kdbus_queue_entry *entry) +{ + struct kdbus_queue *queue = &entry->conn->queue; + struct rb_node **n, *pn = NULL; + bool highest = true; + + lockdep_assert_held(&entry->conn->lock); + if (WARN_ON(!list_empty(&entry->entry))) + return; + + /* sort into priority entry tree */ + n = &queue->msg_prio_queue.rb_node; + while (*n) { + struct kdbus_queue_entry *e; + + pn = *n; + e = rb_entry(pn, struct kdbus_queue_entry, prio_node); + + /* existing node for this priority, add to its list */ + if (likely(entry->priority == e->priority)) { + list_add_tail(&entry->prio_entry, &e->prio_entry); + goto prio_done; + } + + if (entry->priority < e->priority) { + n = &pn->rb_left; + } else { + n = &pn->rb_right; + highest = false; + } + } + + /* cache highest-priority entry */ + if (highest) + queue->msg_prio_highest = &entry->prio_node; + + /* new node for this priority */ + rb_link_node(&entry->prio_node, pn, n); + rb_insert_color(&entry->prio_node, &queue->msg_prio_queue); + INIT_LIST_HEAD(&entry->prio_entry); + +prio_done: + /* add to unsorted fifo list */ + list_add_tail(&entry->entry, &queue->msg_list); +} + +static void kdbus_queue_entry_unlink(struct kdbus_queue_entry *entry) +{ + struct kdbus_queue *queue = &entry->conn->queue; + + lockdep_assert_held(&entry->conn->lock); + if (list_empty(&entry->entry)) + return; + + list_del_init(&entry->entry); + + if (list_empty(&entry->prio_entry)) { + /* + * Single entry for this priority, update cached + * highest-priority entry, remove the tree node. + */ + if (queue->msg_prio_highest == &entry->prio_node) + queue->msg_prio_highest = rb_next(&entry->prio_node); + + rb_erase(&entry->prio_node, &queue->msg_prio_queue); + } else { + struct kdbus_queue_entry *q; + + /* + * Multiple entries for this priority entry, get next one in + * the list. Update cached highest-priority entry, store the + * new one as the tree node. + */ + q = list_first_entry(&entry->prio_entry, + struct kdbus_queue_entry, prio_entry); + list_del(&entry->prio_entry); + + if (queue->msg_prio_highest == &entry->prio_node) + queue->msg_prio_highest = &q->prio_node; + + rb_replace_node(&entry->prio_node, &q->prio_node, + &queue->msg_prio_queue); + } +} + +/** + * kdbus_queue_entry_new() - allocate a queue entry + * @conn_dst: destination connection + * @kmsg: kmsg object the queue entry should track + * @user: user to account message on (or NULL for kernel messages) + * + * Allocates a queue entry based on a given kmsg and allocate space for + * the message payload and the requested metadata in the connection's pool. + * The entry is not actually added to the queue's lists at this point. + * + * Return: the allocated entry on success, or an ERR_PTR on failures. + */ +struct kdbus_queue_entry *kdbus_queue_entry_new(struct kdbus_conn *conn_dst, + const struct kdbus_kmsg *kmsg, + struct kdbus_user *user) +{ + struct kdbus_msg_resources *res = kmsg->res; + const struct kdbus_msg *msg = &kmsg->msg; + struct kdbus_queue_entry *entry; + size_t memfd_cnt = 0; + struct kvec kvec[2]; + size_t meta_size; + size_t msg_size; + u64 payload_off; + u64 size = 0; + int ret = 0; + + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return ERR_PTR(-ENOMEM); + + INIT_LIST_HEAD(&entry->entry); + entry->priority = msg->priority; + entry->dst_name_id = kmsg->dst_name_id; + entry->msg_res = kdbus_msg_resources_ref(res); + entry->proc_meta = kdbus_meta_proc_ref(kmsg->proc_meta); + entry->conn_meta = kdbus_meta_conn_ref(kmsg->conn_meta); + entry->conn = kdbus_conn_ref(conn_dst); + + if (kmsg->msg.src_id == KDBUS_SRC_ID_KERNEL) + msg_size = msg->size; + else + msg_size = offsetof(struct kdbus_msg, items); + + /* sum up the size of the needed slice */ + size = msg_size; + + if (res) { + size += res->vec_count * + KDBUS_ITEM_SIZE(sizeof(struct kdbus_vec)); + + if (res->memfd_count) { + entry->memfd_offset = + kcalloc(res->memfd_count, sizeof(size_t), + GFP_KERNEL); + if (!entry->memfd_offset) { + ret = -ENOMEM; + goto exit_free_entry; + } + + size += res->memfd_count * + KDBUS_ITEM_SIZE(sizeof(struct kdbus_memfd)); + } + + if (res->fds_count) + size += KDBUS_ITEM_SIZE(sizeof(int) * res->fds_count); + + if (res->dst_name) + size += KDBUS_ITEM_SIZE(strlen(res->dst_name) + 1); + } + + /* + * Remember the offset of the metadata part, so we can override + * this part later during kdbus_queue_entry_install(). + */ + entry->meta_offset = size; + + if (entry->proc_meta || entry->conn_meta) { + entry->attach_flags = + atomic64_read(&conn_dst->attach_flags_recv); + + ret = kdbus_meta_export_prepare(entry->proc_meta, + entry->conn_meta, + &entry->attach_flags, + &meta_size); + if (ret < 0) + goto exit_free_entry; + + size += meta_size; + } + + payload_off = size; + size += kmsg->pool_size; + size = KDBUS_ALIGN8(size); + + ret = kdbus_conn_quota_inc(conn_dst, user, size, + res ? res->fds_count : 0); + if (ret < 0) + goto exit_free_entry; + + entry->slice = kdbus_pool_slice_alloc(conn_dst->pool, size, true); + if (IS_ERR(entry->slice)) { + ret = PTR_ERR(entry->slice); + entry->slice = NULL; + kdbus_conn_quota_dec(conn_dst, user, size, + res ? res->fds_count : 0); + goto exit_free_entry; + } + + /* we accounted for exactly 'size' bytes, make sure it didn't grow */ + WARN_ON(kdbus_pool_slice_size(entry->slice) != size); + entry->user = kdbus_user_ref(user); + + /* copy message header */ + kvec[0].iov_base = (char *)msg; + kvec[0].iov_len = msg_size; + + ret = kdbus_pool_slice_copy_kvec(entry->slice, 0, kvec, 1, msg_size); + if (ret < 0) + goto exit_free_entry; + + /* 'size' will now track the write position */ + size = msg_size; + + /* create message payload items */ + if (res) { + size_t dst_name_len = 0; + unsigned int i; + size_t sz = 0; + + if (res->dst_name) { + dst_name_len = strlen(res->dst_name) + 1; + sz += KDBUS_ITEM_SIZE(dst_name_len); + } + + for (i = 0; i < res->data_count; ++i) { + struct kdbus_vec v; + struct kdbus_memfd m; + + switch (res->data[i].type) { + case KDBUS_MSG_DATA_VEC: + sz += KDBUS_ITEM_SIZE(sizeof(v)); + break; + + case KDBUS_MSG_DATA_MEMFD: + sz += KDBUS_ITEM_SIZE(sizeof(m)); + break; + } + } + + if (sz) { + struct kdbus_item *items, *item; + + items = kmalloc(sz, GFP_KERNEL); + if (!items) { + ret = -ENOMEM; + goto exit_free_entry; + } + + item = items; + + if (res->dst_name) + item = kdbus_item_set(item, KDBUS_ITEM_DST_NAME, + res->dst_name, + dst_name_len); + + for (i = 0; i < res->data_count; ++i) { + struct kdbus_msg_data *d = res->data + i; + struct kdbus_memfd m = {}; + struct kdbus_vec v = {}; + + switch (d->type) { + case KDBUS_MSG_DATA_VEC: + v.size = d->size; + v.offset = d->vec.off; + if (v.offset != ~0ULL) + v.offset += payload_off; + + item = kdbus_item_set(item, + KDBUS_ITEM_PAYLOAD_OFF, + &v, sizeof(v)); + break; + + case KDBUS_MSG_DATA_MEMFD: + /* + * Remember the location of memfds, so + * we can override the content from + * kdbus_queue_entry_install(). + */ + entry->memfd_offset[memfd_cnt++] = + msg_size + + (char *)item - (char *)items + + offsetof(struct kdbus_item, + memfd); + + item = kdbus_item_set(item, + KDBUS_ITEM_PAYLOAD_MEMFD, + &m, sizeof(m)); + break; + } + } + + kvec[0].iov_base = items; + kvec[0].iov_len = sz; + + ret = kdbus_pool_slice_copy_kvec(entry->slice, size, + kvec, 1, sz); + kfree(items); + + if (ret < 0) + goto exit_free_entry; + + size += sz; + } + + /* + * Remember the location of the FD part, so we can override the + * content in kdbus_queue_entry_install(). + */ + if (res->fds_count) { + entry->fds_offset = size; + size += KDBUS_ITEM_SIZE(sizeof(int) * res->fds_count); + } + } + + /* finally, copy over the actual message payload */ + if (kmsg->iov_count) { + ret = kdbus_pool_slice_copy_iovec(entry->slice, payload_off, + kmsg->iov, + kmsg->iov_count, + kmsg->pool_size); + if (ret < 0) + goto exit_free_entry; + } + + return entry; + +exit_free_entry: + kdbus_queue_entry_free(entry); + return ERR_PTR(ret); +} + +/** + * kdbus_queue_entry_free() - free resources of an entry + * @entry: The entry to free + * + * Removes resources allocated by a queue entry, along with the entry itself. + * Note that the entry's slice is not freed at this point. + */ +void kdbus_queue_entry_free(struct kdbus_queue_entry *entry) +{ + if (!entry) + return; + + lockdep_assert_held(&entry->conn->lock); + + kdbus_queue_entry_unlink(entry); + kdbus_reply_unref(entry->reply); + + if (entry->slice) { + kdbus_conn_quota_dec(entry->conn, entry->user, + kdbus_pool_slice_size(entry->slice), + entry->msg_res ? + entry->msg_res->fds_count : 0); + kdbus_pool_slice_release(entry->slice); + kdbus_user_unref(entry->user); + } + + kdbus_msg_resources_unref(entry->msg_res); + kdbus_meta_conn_unref(entry->conn_meta); + kdbus_meta_proc_unref(entry->proc_meta); + kdbus_conn_unref(entry->conn); + kfree(entry->memfd_offset); + kfree(entry); +} + +/** + * kdbus_queue_entry_install() - install message components into the + * receiver's process + * @entry: The queue entry to install + * @return_flags: Pointer to store the return flags for userspace + * @install_fds: Whether or not to install associated file descriptors + * + * This function will create a slice to transport the message header, the + * metadata items and other items for information stored in @entry, and + * store it as entry->slice. + * + * If @install_fds is %true, file descriptors will as well be installed. + * This function must always be called from the task context of the receiver. + * + * Return: 0 on success. + */ +int kdbus_queue_entry_install(struct kdbus_queue_entry *entry, + u64 *return_flags, bool install_fds) +{ + u64 msg_size = entry->meta_offset; + struct kdbus_conn *conn_dst = entry->conn; + struct kdbus_msg_resources *res; + bool incomplete_fds = false; + struct kvec kvec[2]; + size_t memfds = 0; + int i, ret; + + lockdep_assert_held(&conn_dst->lock); + + if (entry->proc_meta || entry->conn_meta) { + size_t meta_size; + + ret = kdbus_meta_export(entry->proc_meta, + entry->conn_meta, + entry->attach_flags, + entry->slice, + entry->meta_offset, + &meta_size); + if (ret < 0) + return ret; + + msg_size += meta_size; + } + + /* Update message size at offset 0 */ + kvec[0].iov_base = &msg_size; + kvec[0].iov_len = sizeof(msg_size); + + ret = kdbus_pool_slice_copy_kvec(entry->slice, 0, kvec, 1, + sizeof(msg_size)); + if (ret < 0) + return ret; + + res = entry->msg_res; + + if (!res) + return 0; + + if (res->fds_count) { + struct kdbus_item_header hdr; + size_t off; + int *fds; + + fds = kmalloc_array(res->fds_count, sizeof(int), GFP_KERNEL); + if (!fds) + return -ENOMEM; + + for (i = 0; i < res->fds_count; i++) { + if (install_fds) { + fds[i] = get_unused_fd_flags(O_CLOEXEC); + if (fds[i] >= 0) + fd_install(fds[i], + get_file(res->fds[i])); + else + incomplete_fds = true; + } else { + fds[i] = -1; + } + } + + off = entry->fds_offset; + + hdr.type = KDBUS_ITEM_FDS; + hdr.size = KDBUS_ITEM_HEADER_SIZE + + sizeof(int) * res->fds_count; + + kvec[0].iov_base = &hdr; + kvec[0].iov_len = sizeof(hdr); + + kvec[1].iov_base = fds; + kvec[1].iov_len = sizeof(int) * res->fds_count; + + ret = kdbus_pool_slice_copy_kvec(entry->slice, off, + kvec, 2, hdr.size); + kfree(fds); + + if (ret < 0) + return ret; + } + + for (i = 0; i < res->data_count; ++i) { + struct kdbus_msg_data *d = res->data + i; + struct kdbus_memfd m; + + if (d->type != KDBUS_MSG_DATA_MEMFD) + continue; + + m.start = d->memfd.start; + m.size = d->size; + m.fd = -1; + + if (install_fds) { + m.fd = get_unused_fd_flags(O_CLOEXEC); + if (m.fd < 0) { + m.fd = -1; + incomplete_fds = true; + } else { + fd_install(m.fd, + get_file(d->memfd.file)); + } + } + + kvec[0].iov_base = &m; + kvec[0].iov_len = sizeof(m); + + ret = kdbus_pool_slice_copy_kvec(entry->slice, + entry->memfd_offset[memfds++], + kvec, 1, sizeof(m)); + if (ret < 0) + return ret; + } + + if (incomplete_fds) + *return_flags |= KDBUS_RECV_RETURN_INCOMPLETE_FDS; + + return 0; +} + +/** + * kdbus_queue_entry_enqueue() - enqueue an entry + * @entry: entry to enqueue + * @reply: reply to link to this entry (or NULL if none) + * + * This enqueues an unqueued entry into the message queue of the linked + * connection. It also binds a reply object to the entry so we can remember it + * when the message is moved. + * + * Once this call returns (and the connection lock is released), this entry can + * be dequeued by the target connection. Note that the entry will not be removed + * from the queue until it is destroyed. + */ +void kdbus_queue_entry_enqueue(struct kdbus_queue_entry *entry, + struct kdbus_reply *reply) +{ + lockdep_assert_held(&entry->conn->lock); + + if (WARN_ON(entry->reply) || WARN_ON(!list_empty(&entry->entry))) + return; + + entry->reply = kdbus_reply_ref(reply); + kdbus_queue_entry_link(entry); +} + +/** + * kdbus_queue_entry_move() - move queue entry + * @e: queue entry to move + * @dst: destination connection to queue the entry on + * + * This moves a queue entry onto a different connection. It allocates a new + * slice on the target connection and copies the message over. If the copy + * succeeded, we move the entry from @src to @dst. + * + * On failure, the entry is left untouched. + * + * The queue entry must be queued right now, and after the call succeeds it will + * be queued on the destination, but no longer on the source. + * + * The caller must hold the connection lock of the source *and* destination. + * + * Return: 0 on success, negative error code on failure. + */ +int kdbus_queue_entry_move(struct kdbus_queue_entry *e, + struct kdbus_conn *dst) +{ + struct kdbus_pool_slice *slice = NULL; + struct kdbus_conn *src = e->conn; + size_t size, fds; + int ret; + + lockdep_assert_held(&src->lock); + lockdep_assert_held(&dst->lock); + + if (WARN_ON(IS_ERR(e->user)) || WARN_ON(list_empty(&e->entry))) + return -EINVAL; + if (src == dst) + return 0; + + size = kdbus_pool_slice_size(e->slice); + fds = e->msg_res ? e->msg_res->fds_count : 0; + + ret = kdbus_conn_quota_inc(dst, e->user, size, fds); + if (ret < 0) + return ret; + + slice = kdbus_pool_slice_alloc(dst->pool, size, true); + if (IS_ERR(slice)) { + ret = PTR_ERR(slice); + slice = NULL; + goto error; + } + + ret = kdbus_pool_slice_copy(slice, e->slice); + if (ret < 0) + goto error; + + kdbus_queue_entry_unlink(e); + kdbus_conn_quota_dec(src, e->user, size, fds); + kdbus_pool_slice_release(e->slice); + kdbus_conn_unref(e->conn); + + e->slice = slice; + e->conn = kdbus_conn_ref(dst); + kdbus_queue_entry_link(e); + + return 0; + +error: + kdbus_pool_slice_release(slice); + kdbus_conn_quota_dec(dst, e->user, size, fds); + return ret; +} diff --git a/ipc/kdbus/queue.h b/ipc/kdbus/queue.h new file mode 100644 index 00000000000..7f2db96fe30 --- /dev/null +++ b/ipc/kdbus/queue.h @@ -0,0 +1,92 @@ +/* + * 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_QUEUE_H +#define __KDBUS_QUEUE_H + +struct kdbus_user; + +/** + * struct kdbus_queue - a connection's message queue + * @msg_list: List head for kdbus_queue_entry objects + * @msg_prio_queue: RB tree root for messages, sorted by priority + * @msg_prio_highest: Link to the RB node referencing the message with the + * highest priority in the tree. + */ +struct kdbus_queue { + struct list_head msg_list; + struct rb_root msg_prio_queue; + struct rb_node *msg_prio_highest; +}; + +/** + * struct kdbus_queue_entry - messages waiting to be read + * @entry: Entry in the connection's list + * @prio_node: Entry in the priority queue tree + * @prio_entry: Queue tree node entry in the list of one priority + * @slice: Slice in the receiver's pool for the message + * @attach_flags: Attach flags used during slice allocation + * @meta_offset: Offset of first metadata item in slice + * @fds_offset: Offset of FD item in slice + * @memfd_offset: Array of slice-offsets for all memfd items + * @priority: Message priority + * @dst_name_id: The sequence number of the name this message is + * addressed to, 0 for messages sent to an ID + * @msg_res: Message resources + * @proc_meta: Process metadata, captured at message arrival + * @conn_meta: Connection metadata, captured at message arrival + * @reply: The reply block if a reply to this message is expected + * @user: User used for accounting + */ +struct kdbus_queue_entry { + struct list_head entry; + struct rb_node prio_node; + struct list_head prio_entry; + + struct kdbus_pool_slice *slice; + + u64 attach_flags; + size_t meta_offset; + size_t fds_offset; + size_t *memfd_offset; + + s64 priority; + u64 dst_name_id; + + struct kdbus_msg_resources *msg_res; + struct kdbus_meta_proc *proc_meta; + struct kdbus_meta_conn *conn_meta; + struct kdbus_reply *reply; + struct kdbus_conn *conn; + struct kdbus_user *user; +}; + +struct kdbus_kmsg; + +void kdbus_queue_init(struct kdbus_queue *queue); +struct kdbus_queue_entry *kdbus_queue_peek(struct kdbus_queue *queue, + s64 priority, bool use_priority); + +struct kdbus_queue_entry *kdbus_queue_entry_new(struct kdbus_conn *conn_dst, + const struct kdbus_kmsg *kmsg, + struct kdbus_user *user); +void kdbus_queue_entry_free(struct kdbus_queue_entry *entry); +int kdbus_queue_entry_install(struct kdbus_queue_entry *entry, + u64 *return_flags, bool install_fds); +void kdbus_queue_entry_enqueue(struct kdbus_queue_entry *entry, + struct kdbus_reply *reply); +int kdbus_queue_entry_move(struct kdbus_queue_entry *entry, + struct kdbus_conn *dst); + +#endif /* __KDBUS_QUEUE_H */ diff --git a/ipc/kdbus/reply.c b/ipc/kdbus/reply.c new file mode 100644 index 00000000000..6b3bd81bbb4 --- /dev/null +++ b/ipc/kdbus/reply.c @@ -0,0 +1,259 @@ +#include <linux/init.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/uio.h> + +#include "bus.h" +#include "connection.h" +#include "endpoint.h" +#include "message.h" +#include "metadata.h" +#include "names.h" +#include "domain.h" +#include "item.h" +#include "notify.h" +#include "policy.h" +#include "reply.h" +#include "util.h" + +/** + * kdbus_reply_new() - Allocate and set up a new kdbus_reply object + * @reply_src: The connection a reply is expected from + * @reply_dst: The connection this reply object belongs to + * @msg: Message associated with the reply + * @name_entry: Name entry used to send the message + * @sync: Whether or not to make this reply synchronous + * + * Allocate and fill a new kdbus_reply object. + * + * Return: New kdbus_conn object on success, ERR_PTR on error. + */ +struct kdbus_reply *kdbus_reply_new(struct kdbus_conn *reply_src, + struct kdbus_conn *reply_dst, + const struct kdbus_msg *msg, + struct kdbus_name_entry *name_entry, + bool sync) +{ + struct kdbus_reply *r; + int ret = 0; + + if (atomic_inc_return(&reply_dst->request_count) > + KDBUS_CONN_MAX_REQUESTS_PENDING) { + ret = -EMLINK; + goto exit_dec_request_count; + } + + r = kzalloc(sizeof(*r), GFP_KERNEL); + if (!r) { + ret = -ENOMEM; + goto exit_dec_request_count; + } + + kref_init(&r->kref); + INIT_LIST_HEAD(&r->entry); + r->reply_src = kdbus_conn_ref(reply_src); + r->reply_dst = kdbus_conn_ref(reply_dst); + r->cookie = msg->cookie; + r->name_id = name_entry ? name_entry->name_id : 0; + r->deadline_ns = msg->timeout_ns; + + if (sync) { + r->sync = true; + r->waiting = true; + } + +exit_dec_request_count: + if (ret < 0) { + atomic_dec(&reply_dst->request_count); + return ERR_PTR(ret); + } + + return r; +} + +static void __kdbus_reply_free(struct kref *kref) +{ + struct kdbus_reply *reply = + container_of(kref, struct kdbus_reply, kref); + + atomic_dec(&reply->reply_dst->request_count); + kdbus_conn_unref(reply->reply_src); + kdbus_conn_unref(reply->reply_dst); + kfree(reply); +} + +/** + * kdbus_reply_ref() - Increase reference on kdbus_reply + * @r: The reply, may be %NULL + * + * Return: The reply object with an extra reference + */ +struct kdbus_reply *kdbus_reply_ref(struct kdbus_reply *r) +{ + if (r) + kref_get(&r->kref); + return r; +} + +/** + * kdbus_reply_unref() - Decrease reference on kdbus_reply + * @r: The reply, may be %NULL + * + * Return: NULL + */ +struct kdbus_reply *kdbus_reply_unref(struct kdbus_reply *r) +{ + if (r) + kref_put(&r->kref, __kdbus_reply_free); + return NULL; +} + +/** + * kdbus_reply_link() - Link reply object into target connection + * @r: Reply to link + */ +void kdbus_reply_link(struct kdbus_reply *r) +{ + if (WARN_ON(!list_empty(&r->entry))) + return; + + list_add(&r->entry, &r->reply_dst->reply_list); + kdbus_reply_ref(r); +} + +/** + * kdbus_reply_unlink() - Unlink reply object from target connection + * @r: Reply to unlink + */ +void kdbus_reply_unlink(struct kdbus_reply *r) +{ + if (!list_empty(&r->entry)) { + list_del_init(&r->entry); + kdbus_reply_unref(r); + } +} + +/** + * kdbus_sync_reply_wakeup() - Wake a synchronously blocking reply + * @reply: The reply object + * @err: Error code to set on the remote side + * + * Remove the synchronous reply object from its connection reply_list, and + * wake up remote peer (method origin) with the appropriate synchronous reply + * code. + */ +void kdbus_sync_reply_wakeup(struct kdbus_reply *reply, int err) +{ + if (WARN_ON(!reply->sync)) + return; + + reply->waiting = false; + reply->err = err; + wake_up_interruptible(&reply->reply_dst->wait); +} + +/** + * kdbus_reply_find() - Find the corresponding reply object + * @replying: The replying connection or NULL + * @reply_dst: The connection the reply will be sent to + * (method origin) + * @cookie: The cookie of the requesting message + * + * Lookup a reply object that should be sent as a reply by + * @replying to @reply_dst with the given cookie. + * + * Callers must take the @reply_dst lock. + * + * Return: the corresponding reply object or NULL if not found + */ +struct kdbus_reply *kdbus_reply_find(struct kdbus_conn *replying, + struct kdbus_conn *reply_dst, + u64 cookie) +{ + struct kdbus_reply *r, *reply = NULL; + + list_for_each_entry(r, &reply_dst->reply_list, entry) { + if (r->cookie == cookie && + (!replying || r->reply_src == replying)) { + reply = r; + break; + } + } + + return reply; +} + +/** + * kdbus_reply_list_scan_work() - Worker callback to scan the replies of a + * connection for exceeded timeouts + * @work: Work struct of the connection to scan + * + * Walk the list of replies stored with a connection and look for entries + * that have exceeded their timeout. If such an entry is found, a timeout + * notification is sent to the waiting peer, and the reply is removed from + * the list. + * + * The work is rescheduled to the nearest timeout found during the list + * iteration. + */ +void kdbus_reply_list_scan_work(struct work_struct *work) +{ + struct kdbus_conn *conn = + container_of(work, struct kdbus_conn, work.work); + struct kdbus_reply *reply, *reply_tmp; + u64 deadline = ~0ULL; + struct timespec64 ts; + u64 now; + + ktime_get_ts64(&ts); + now = timespec64_to_ns(&ts); + + mutex_lock(&conn->lock); + if (!kdbus_conn_active(conn)) { + mutex_unlock(&conn->lock); + return; + } + + list_for_each_entry_safe(reply, reply_tmp, &conn->reply_list, entry) { + /* + * If the reply block is waiting for synchronous I/O, + * the timeout is handled by wait_event_*_timeout(), + * so we don't have to care for it here. + */ + if (reply->sync && !reply->interrupted) + continue; + + WARN_ON(reply->reply_dst != conn); + + if (reply->deadline_ns > now) { + /* remember next timeout */ + if (deadline > reply->deadline_ns) + deadline = reply->deadline_ns; + + continue; + } + + /* + * A zero deadline means the connection died, was + * cleaned up already and the notification was sent. + * Don't send notifications for reply trackers that were + * left in an interrupted syscall state. + */ + if (reply->deadline_ns != 0 && !reply->interrupted) + kdbus_notify_reply_timeout(conn->ep->bus, conn->id, + reply->cookie); + + kdbus_reply_unlink(reply); + } + + /* rearm delayed work with next timeout */ + if (deadline != ~0ULL) + schedule_delayed_work(&conn->work, + nsecs_to_jiffies(deadline - now)); + + mutex_unlock(&conn->lock); + + kdbus_notify_flush(conn->ep->bus); +} diff --git a/ipc/kdbus/reply.h b/ipc/kdbus/reply.h new file mode 100644 index 00000000000..68d52321a91 --- /dev/null +++ b/ipc/kdbus/reply.h @@ -0,0 +1,68 @@ +/* + * 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_REPLY_H +#define __KDBUS_REPLY_H + +/** + * struct kdbus_reply - an entry of kdbus_conn's list of replies + * @kref: Ref-count of this object + * @entry: The entry of the connection's reply_list + * @reply_src: The connection the reply will be sent from + * @reply_dst: The connection the reply will be sent to + * @queue_entry: The queue entry item that is prepared by the replying + * connection + * @deadline_ns: The deadline of the reply, in nanoseconds + * @cookie: The cookie of the requesting message + * @name_id: ID of the well-known name the original msg was sent to + * @sync: The reply block is waiting for synchronous I/O + * @waiting: The condition to synchronously wait for + * @interrupted: The sync reply was left in an interrupted state + * @err: The error code for the synchronous reply + */ +struct kdbus_reply { + struct kref kref; + struct list_head entry; + struct kdbus_conn *reply_src; + struct kdbus_conn *reply_dst; + struct kdbus_queue_entry *queue_entry; + u64 deadline_ns; + u64 cookie; + u64 name_id; + bool sync:1; + bool waiting:1; + bool interrupted:1; + int err; +}; + +struct kdbus_reply *kdbus_reply_new(struct kdbus_conn *reply_src, + struct kdbus_conn *reply_dst, + const struct kdbus_msg *msg, + struct kdbus_name_entry *name_entry, + bool sync); + +struct kdbus_reply *kdbus_reply_ref(struct kdbus_reply *r); +struct kdbus_reply *kdbus_reply_unref(struct kdbus_reply *r); + +void kdbus_reply_link(struct kdbus_reply *r); +void kdbus_reply_unlink(struct kdbus_reply *r); + +struct kdbus_reply *kdbus_reply_find(struct kdbus_conn *replying, + struct kdbus_conn *reply_dst, + u64 cookie); + +void kdbus_sync_reply_wakeup(struct kdbus_reply *reply, int err); +void kdbus_reply_list_scan_work(struct work_struct *work); + +#endif /* __KDBUS_REPLY_H */ diff --git a/ipc/kdbus/util.h b/ipc/kdbus/util.h index 9caadb33791..740b1988098 100644 --- a/ipc/kdbus/util.h +++ b/ipc/kdbus/util.h @@ -18,7 +18,7 @@ #include <linux/dcache.h> #include <linux/ioctl.h> -#include "kdbus.h" +#include <uapi/linux/kdbus.h> /* all exported addresses are 64 bit */ #define KDBUS_PTR(addr) ((void __user *)(uintptr_t)(addr)) |