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linux/drivers/android/binder.c
Christian Brauner 3ad20fe393 binder: implement binderfs 
As discussed at Linux Plumbers Conference 2018 in Vancouver [1] this is the
implementation of binderfs.

/* Abstract */
binderfs is a backwards-compatible filesystem for Android's binder ipc
mechanism. Each ipc namespace will mount a new binderfs instance. Mounting
binderfs multiple times at different locations in the same ipc namespace
will not cause a new super block to be allocated and hence it will be the
same filesystem instance.
Each new binderfs mount will have its own set of binder devices only
visible in the ipc namespace it has been mounted in. All devices in a new
binderfs mount will follow the scheme binder%d and numbering will always
start at 0.

/* Backwards compatibility */
Devices requested in the Kconfig via CONFIG_ANDROID_BINDER_DEVICES for the
initial ipc namespace will work as before. They will be registered via
misc_register() and appear in the devtmpfs mount. Specifically, the
standard devices binder, hwbinder, and vndbinder will all appear in their
standard locations in /dev. Mounting or unmounting the binderfs mount in
the initial ipc namespace will have no effect on these devices, i.e. they
will neither show up in the binderfs mount nor will they disappear when the
binderfs mount is gone.

/* binder-control */
Each new binderfs instance comes with a binder-control device. No other
devices will be present at first. The binder-control device can be used to
dynamically allocate binder devices. All requests operate on the binderfs
mount the binder-control device resides in.
Assuming a new instance of binderfs has been mounted at /dev/binderfs
via mount -t binderfs binderfs /dev/binderfs. Then a request to create a
new binder device can be made as illustrated in [2].
Binderfs devices can simply be removed via unlink().

/* Implementation details */
- dynamic major number allocation:
  When binderfs is registered as a new filesystem it will dynamically
  allocate a new major number. The allocated major number will be returned
  in struct binderfs_device when a new binder device is allocated.
- global minor number tracking:
  Minor are tracked in a global idr struct that is capped at
  BINDERFS_MAX_MINOR. The minor number tracker is protected by a global
  mutex. This is the only point of contention between binderfs mounts.
- struct binderfs_info:
  Each binderfs super block has its own struct binderfs_info that tracks
  specific details about a binderfs instance:
  - ipc namespace
  - dentry of the binder-control device
  - root uid and root gid of the user namespace the binderfs instance
    was mounted in
- mountable by user namespace root:
  binderfs can be mounted by user namespace root in a non-initial user
  namespace. The devices will be owned by user namespace root.
- binderfs binder devices without misc infrastructure:
  New binder devices associated with a binderfs mount do not use the
  full misc_register() infrastructure.
  The misc_register() infrastructure can only create new devices in the
  host's devtmpfs mount. binderfs does however only make devices appear
  under its own mountpoint and thus allocates new character device nodes
  from the inode of the root dentry of the super block. This will have
  the side-effect that binderfs specific device nodes do not appear in
  sysfs. This behavior is similar to devpts allocated pts devices and
  has no effect on the functionality of the ipc mechanism itself.

[1]: https://goo.gl/JL2tfX
[2]: program to allocate a new binderfs binder device:

     #define _GNU_SOURCE
     #include <errno.h>
     #include <fcntl.h>
     #include <stdio.h>
     #include <stdlib.h>
     #include <string.h>
     #include <sys/ioctl.h>
     #include <sys/stat.h>
     #include <sys/types.h>
     #include <unistd.h>
     #include <linux/android/binder_ctl.h>

     int main(int argc, char *argv[])
     {
             int fd, ret, saved_errno;
             size_t len;
             struct binderfs_device device = { 0 };

             if (argc < 2)
                     exit(EXIT_FAILURE);

             len = strlen(argv[1]);
             if (len > BINDERFS_MAX_NAME)
                     exit(EXIT_FAILURE);

             memcpy(device.name, argv[1], len);

             fd = open("/dev/binderfs/binder-control", O_RDONLY | O_CLOEXEC);
             if (fd < 0) {
                     printf("%s - Failed to open binder-control device\n",
                            strerror(errno));
                     exit(EXIT_FAILURE);
             }

             ret = ioctl(fd, BINDER_CTL_ADD, &device);
             saved_errno = errno;
             close(fd);
             errno = saved_errno;
             if (ret < 0) {
                     printf("%s - Failed to allocate new binder device\n",
                            strerror(errno));
                     exit(EXIT_FAILURE);
             }

             printf("Allocated new binder device with major %d, minor %d, and "
                    "name %s\n", device.major, device.minor,
                    device.name);

             exit(EXIT_SUCCESS);
     }

Cc: Martijn Coenen <maco@android.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-19 09:40:13 +01:00

5941 lines
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/* binder.c
*
* Android IPC Subsystem
*
* Copyright (C) 2007-2008 Google, Inc.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
/*
* Locking overview
*
* There are 3 main spinlocks which must be acquired in the
* order shown:
*
* 1) proc->outer_lock : protects binder_ref
* binder_proc_lock() and binder_proc_unlock() are
* used to acq/rel.
* 2) node->lock : protects most fields of binder_node.
* binder_node_lock() and binder_node_unlock() are
* used to acq/rel
* 3) proc->inner_lock : protects the thread and node lists
* (proc->threads, proc->waiting_threads, proc->nodes)
* and all todo lists associated with the binder_proc
* (proc->todo, thread->todo, proc->delivered_death and
* node->async_todo), as well as thread->transaction_stack
* binder_inner_proc_lock() and binder_inner_proc_unlock()
* are used to acq/rel
*
* Any lock under procA must never be nested under any lock at the same
* level or below on procB.
*
* Functions that require a lock held on entry indicate which lock
* in the suffix of the function name:
*
* foo_olocked() : requires node->outer_lock
* foo_nlocked() : requires node->lock
* foo_ilocked() : requires proc->inner_lock
* foo_oilocked(): requires proc->outer_lock and proc->inner_lock
* foo_nilocked(): requires node->lock and proc->inner_lock
* ...
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/fdtable.h>
#include <linux/file.h>
#include <linux/freezer.h>
#include <linux/fs.h>
#include <linux/list.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/nsproxy.h>
#include <linux/poll.h>
#include <linux/debugfs.h>
#include <linux/rbtree.h>
#include <linux/sched/signal.h>
#include <linux/sched/mm.h>
#include <linux/seq_file.h>
#include <linux/uaccess.h>
#include <linux/pid_namespace.h>
#include <linux/security.h>
#include <linux/spinlock.h>
#include <linux/ratelimit.h>
#include <linux/syscalls.h>
#include <linux/task_work.h>
#include <uapi/linux/android/binder.h>
#include <asm/cacheflush.h>
#include "binder_alloc.h"
#include "binder_internal.h"
#include "binder_trace.h"
static HLIST_HEAD(binder_deferred_list);
static DEFINE_MUTEX(binder_deferred_lock);
static HLIST_HEAD(binder_devices);
static HLIST_HEAD(binder_procs);
static DEFINE_MUTEX(binder_procs_lock);
static HLIST_HEAD(binder_dead_nodes);
static DEFINE_SPINLOCK(binder_dead_nodes_lock);
static struct dentry *binder_debugfs_dir_entry_root;
static struct dentry *binder_debugfs_dir_entry_proc;
static atomic_t binder_last_id;
static int proc_show(struct seq_file *m, void *unused);
DEFINE_SHOW_ATTRIBUTE(proc);
/* This is only defined in include/asm-arm/sizes.h */
#ifndef SZ_1K
#define SZ_1K 0x400
#endif
#ifndef SZ_4M
#define SZ_4M 0x400000
#endif
#define FORBIDDEN_MMAP_FLAGS (VM_WRITE)
enum {
BINDER_DEBUG_USER_ERROR = 1U << 0,
BINDER_DEBUG_FAILED_TRANSACTION = 1U << 1,
BINDER_DEBUG_DEAD_TRANSACTION = 1U << 2,
BINDER_DEBUG_OPEN_CLOSE = 1U << 3,
BINDER_DEBUG_DEAD_BINDER = 1U << 4,
BINDER_DEBUG_DEATH_NOTIFICATION = 1U << 5,
BINDER_DEBUG_READ_WRITE = 1U << 6,
BINDER_DEBUG_USER_REFS = 1U << 7,
BINDER_DEBUG_THREADS = 1U << 8,
BINDER_DEBUG_TRANSACTION = 1U << 9,
BINDER_DEBUG_TRANSACTION_COMPLETE = 1U << 10,
BINDER_DEBUG_FREE_BUFFER = 1U << 11,
BINDER_DEBUG_INTERNAL_REFS = 1U << 12,
BINDER_DEBUG_PRIORITY_CAP = 1U << 13,
BINDER_DEBUG_SPINLOCKS = 1U << 14,
};
static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR |
BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION;
module_param_named(debug_mask, binder_debug_mask, uint, 0644);
static char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES;
module_param_named(devices, binder_devices_param, charp, 0444);
static DECLARE_WAIT_QUEUE_HEAD(binder_user_error_wait);
static int binder_stop_on_user_error;
static int binder_set_stop_on_user_error(const char *val,
const struct kernel_param *kp)
{
int ret;
ret = param_set_int(val, kp);
if (binder_stop_on_user_error < 2)
wake_up(&binder_user_error_wait);
return ret;
}
module_param_call(stop_on_user_error, binder_set_stop_on_user_error,
param_get_int, &binder_stop_on_user_error, 0644);
#define binder_debug(mask, x...) \
do { \
if (binder_debug_mask & mask) \
pr_info_ratelimited(x); \
} while (0)
#define binder_user_error(x...) \
do { \
if (binder_debug_mask & BINDER_DEBUG_USER_ERROR) \
pr_info_ratelimited(x); \
if (binder_stop_on_user_error) \
binder_stop_on_user_error = 2; \
} while (0)
#define to_flat_binder_object(hdr) \
container_of(hdr, struct flat_binder_object, hdr)
#define to_binder_fd_object(hdr) container_of(hdr, struct binder_fd_object, hdr)
#define to_binder_buffer_object(hdr) \
container_of(hdr, struct binder_buffer_object, hdr)
#define to_binder_fd_array_object(hdr) \
container_of(hdr, struct binder_fd_array_object, hdr)
enum binder_stat_types {
BINDER_STAT_PROC,
BINDER_STAT_THREAD,
BINDER_STAT_NODE,
BINDER_STAT_REF,
BINDER_STAT_DEATH,
BINDER_STAT_TRANSACTION,
BINDER_STAT_TRANSACTION_COMPLETE,
BINDER_STAT_COUNT
};
struct binder_stats {
atomic_t br[_IOC_NR(BR_FAILED_REPLY) + 1];
atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1];
atomic_t obj_created[BINDER_STAT_COUNT];
atomic_t obj_deleted[BINDER_STAT_COUNT];
};
static struct binder_stats binder_stats;
static inline void binder_stats_deleted(enum binder_stat_types type)
{
atomic_inc(&binder_stats.obj_deleted[type]);
}
static inline void binder_stats_created(enum binder_stat_types type)
{
atomic_inc(&binder_stats.obj_created[type]);
}
struct binder_transaction_log_entry {
int debug_id;
int debug_id_done;
int call_type;
int from_proc;
int from_thread;
int target_handle;
int to_proc;
int to_thread;
int to_node;
int data_size;
int offsets_size;
int return_error_line;
uint32_t return_error;
uint32_t return_error_param;
const char *context_name;
};
struct binder_transaction_log {
atomic_t cur;
bool full;
struct binder_transaction_log_entry entry[32];
};
static struct binder_transaction_log binder_transaction_log;
static struct binder_transaction_log binder_transaction_log_failed;
static struct binder_transaction_log_entry *binder_transaction_log_add(
struct binder_transaction_log *log)
{
struct binder_transaction_log_entry *e;
unsigned int cur = atomic_inc_return(&log->cur);
if (cur >= ARRAY_SIZE(log->entry))
log->full = true;
e = &log->entry[cur % ARRAY_SIZE(log->entry)];
WRITE_ONCE(e->debug_id_done, 0);
/*
* write-barrier to synchronize access to e->debug_id_done.
* We make sure the initialized 0 value is seen before
* memset() other fields are zeroed by memset.
*/
smp_wmb();
memset(e, 0, sizeof(*e));
return e;
}
/**
* struct binder_work - work enqueued on a worklist
* @entry: node enqueued on list
* @type: type of work to be performed
*
* There are separate work lists for proc, thread, and node (async).
*/
struct binder_work {
struct list_head entry;
enum {
BINDER_WORK_TRANSACTION = 1,
BINDER_WORK_TRANSACTION_COMPLETE,
BINDER_WORK_RETURN_ERROR,
BINDER_WORK_NODE,
BINDER_WORK_DEAD_BINDER,
BINDER_WORK_DEAD_BINDER_AND_CLEAR,
BINDER_WORK_CLEAR_DEATH_NOTIFICATION,
} type;
};
struct binder_error {
struct binder_work work;
uint32_t cmd;
};
/**
* struct binder_node - binder node bookkeeping
* @debug_id: unique ID for debugging
* (invariant after initialized)
* @lock: lock for node fields
* @work: worklist element for node work
* (protected by @proc->inner_lock)
* @rb_node: element for proc->nodes tree
* (protected by @proc->inner_lock)
* @dead_node: element for binder_dead_nodes list
* (protected by binder_dead_nodes_lock)
* @proc: binder_proc that owns this node
* (invariant after initialized)
* @refs: list of references on this node
* (protected by @lock)
* @internal_strong_refs: used to take strong references when
* initiating a transaction
* (protected by @proc->inner_lock if @proc
* and by @lock)
* @local_weak_refs: weak user refs from local process
* (protected by @proc->inner_lock if @proc
* and by @lock)
* @local_strong_refs: strong user refs from local process
* (protected by @proc->inner_lock if @proc
* and by @lock)
* @tmp_refs: temporary kernel refs
* (protected by @proc->inner_lock while @proc
* is valid, and by binder_dead_nodes_lock
* if @proc is NULL. During inc/dec and node release
* it is also protected by @lock to provide safety
* as the node dies and @proc becomes NULL)
* @ptr: userspace pointer for node
* (invariant, no lock needed)
* @cookie: userspace cookie for node
* (invariant, no lock needed)
* @has_strong_ref: userspace notified of strong ref
* (protected by @proc->inner_lock if @proc
* and by @lock)
* @pending_strong_ref: userspace has acked notification of strong ref
* (protected by @proc->inner_lock if @proc
* and by @lock)
* @has_weak_ref: userspace notified of weak ref
* (protected by @proc->inner_lock if @proc
* and by @lock)
* @pending_weak_ref: userspace has acked notification of weak ref
* (protected by @proc->inner_lock if @proc
* and by @lock)
* @has_async_transaction: async transaction to node in progress
* (protected by @lock)
* @accept_fds: file descriptor operations supported for node
* (invariant after initialized)
* @min_priority: minimum scheduling priority
* (invariant after initialized)
* @async_todo: list of async work items
* (protected by @proc->inner_lock)
*
* Bookkeeping structure for binder nodes.
*/
struct binder_node {
int debug_id;
spinlock_t lock;
struct binder_work work;
union {
struct rb_node rb_node;
struct hlist_node dead_node;
};
struct binder_proc *proc;
struct hlist_head refs;
int internal_strong_refs;
int local_weak_refs;
int local_strong_refs;
int tmp_refs;
binder_uintptr_t ptr;
binder_uintptr_t cookie;
struct {
/*
* bitfield elements protected by
* proc inner_lock
*/
u8 has_strong_ref:1;
u8 pending_strong_ref:1;
u8 has_weak_ref:1;
u8 pending_weak_ref:1;
};
struct {
/*
* invariant after initialization
*/
u8 accept_fds:1;
u8 min_priority;
};
bool has_async_transaction;
struct list_head async_todo;
};
struct binder_ref_death {
/**
* @work: worklist element for death notifications
* (protected by inner_lock of the proc that
* this ref belongs to)
*/
struct binder_work work;
binder_uintptr_t cookie;
};
/**
* struct binder_ref_data - binder_ref counts and id
* @debug_id: unique ID for the ref
* @desc: unique userspace handle for ref
* @strong: strong ref count (debugging only if not locked)
* @weak: weak ref count (debugging only if not locked)
*
* Structure to hold ref count and ref id information. Since
* the actual ref can only be accessed with a lock, this structure
* is used to return information about the ref to callers of
* ref inc/dec functions.
*/
struct binder_ref_data {
int debug_id;
uint32_t desc;
int strong;
int weak;
};
/**
* struct binder_ref - struct to track references on nodes
* @data: binder_ref_data containing id, handle, and current refcounts
* @rb_node_desc: node for lookup by @data.desc in proc's rb_tree
* @rb_node_node: node for lookup by @node in proc's rb_tree
* @node_entry: list entry for node->refs list in target node
* (protected by @node->lock)
* @proc: binder_proc containing ref
* @node: binder_node of target node. When cleaning up a
* ref for deletion in binder_cleanup_ref, a non-NULL
* @node indicates the node must be freed
* @death: pointer to death notification (ref_death) if requested
* (protected by @node->lock)
*
* Structure to track references from procA to target node (on procB). This
* structure is unsafe to access without holding @proc->outer_lock.
*/
struct binder_ref {
/* Lookups needed: */
/* node + proc => ref (transaction) */
/* desc + proc => ref (transaction, inc/dec ref) */
/* node => refs + procs (proc exit) */
struct binder_ref_data data;
struct rb_node rb_node_desc;
struct rb_node rb_node_node;
struct hlist_node node_entry;
struct binder_proc *proc;
struct binder_node *node;
struct binder_ref_death *death;
};
enum binder_deferred_state {
BINDER_DEFERRED_FLUSH = 0x01,
BINDER_DEFERRED_RELEASE = 0x02,
};
/**
* struct binder_proc - binder process bookkeeping
* @proc_node: element for binder_procs list
* @threads: rbtree of binder_threads in this proc
* (protected by @inner_lock)
* @nodes: rbtree of binder nodes associated with
* this proc ordered by node->ptr
* (protected by @inner_lock)
* @refs_by_desc: rbtree of refs ordered by ref->desc
* (protected by @outer_lock)
* @refs_by_node: rbtree of refs ordered by ref->node
* (protected by @outer_lock)
* @waiting_threads: threads currently waiting for proc work
* (protected by @inner_lock)
* @pid PID of group_leader of process
* (invariant after initialized)
* @tsk task_struct for group_leader of process
* (invariant after initialized)
* @deferred_work_node: element for binder_deferred_list
* (protected by binder_deferred_lock)
* @deferred_work: bitmap of deferred work to perform
* (protected by binder_deferred_lock)
* @is_dead: process is dead and awaiting free
* when outstanding transactions are cleaned up
* (protected by @inner_lock)
* @todo: list of work for this process
* (protected by @inner_lock)
* @stats: per-process binder statistics
* (atomics, no lock needed)
* @delivered_death: list of delivered death notification
* (protected by @inner_lock)
* @max_threads: cap on number of binder threads
* (protected by @inner_lock)
* @requested_threads: number of binder threads requested but not
* yet started. In current implementation, can
* only be 0 or 1.
* (protected by @inner_lock)
* @requested_threads_started: number binder threads started
* (protected by @inner_lock)
* @tmp_ref: temporary reference to indicate proc is in use
* (protected by @inner_lock)
* @default_priority: default scheduler priority
* (invariant after initialized)
* @debugfs_entry: debugfs node
* @alloc: binder allocator bookkeeping
* @context: binder_context for this proc
* (invariant after initialized)
* @inner_lock: can nest under outer_lock and/or node lock
* @outer_lock: no nesting under innor or node lock
* Lock order: 1) outer, 2) node, 3) inner
*
* Bookkeeping structure for binder processes
*/
struct binder_proc {
struct hlist_node proc_node;
struct rb_root threads;
struct rb_root nodes;
struct rb_root refs_by_desc;
struct rb_root refs_by_node;
struct list_head waiting_threads;
int pid;
struct task_struct *tsk;
struct hlist_node deferred_work_node;
int deferred_work;
bool is_dead;
struct list_head todo;
struct binder_stats stats;
struct list_head delivered_death;
int max_threads;
int requested_threads;
int requested_threads_started;
int tmp_ref;
long default_priority;
struct dentry *debugfs_entry;
struct binder_alloc alloc;
struct binder_context *context;
spinlock_t inner_lock;
spinlock_t outer_lock;
};
enum {
BINDER_LOOPER_STATE_REGISTERED = 0x01,
BINDER_LOOPER_STATE_ENTERED = 0x02,
BINDER_LOOPER_STATE_EXITED = 0x04,
BINDER_LOOPER_STATE_INVALID = 0x08,
BINDER_LOOPER_STATE_WAITING = 0x10,
BINDER_LOOPER_STATE_POLL = 0x20,
};
/**
* struct binder_thread - binder thread bookkeeping
* @proc: binder process for this thread
* (invariant after initialization)
* @rb_node: element for proc->threads rbtree
* (protected by @proc->inner_lock)
* @waiting_thread_node: element for @proc->waiting_threads list
* (protected by @proc->inner_lock)
* @pid: PID for this thread
* (invariant after initialization)
* @looper: bitmap of looping state
* (only accessed by this thread)
* @looper_needs_return: looping thread needs to exit driver
* (no lock needed)
* @transaction_stack: stack of in-progress transactions for this thread
* (protected by @proc->inner_lock)
* @todo: list of work to do for this thread
* (protected by @proc->inner_lock)
* @process_todo: whether work in @todo should be processed
* (protected by @proc->inner_lock)
* @return_error: transaction errors reported by this thread
* (only accessed by this thread)
* @reply_error: transaction errors reported by target thread
* (protected by @proc->inner_lock)
* @wait: wait queue for thread work
* @stats: per-thread statistics
* (atomics, no lock needed)
* @tmp_ref: temporary reference to indicate thread is in use
* (atomic since @proc->inner_lock cannot
* always be acquired)
* @is_dead: thread is dead and awaiting free
* when outstanding transactions are cleaned up
* (protected by @proc->inner_lock)
*
* Bookkeeping structure for binder threads.
*/
struct binder_thread {
struct binder_proc *proc;
struct rb_node rb_node;
struct list_head waiting_thread_node;
int pid;
int looper; /* only modified by this thread */
bool looper_need_return; /* can be written by other thread */
struct binder_transaction *transaction_stack;
struct list_head todo;
bool process_todo;
struct binder_error return_error;
struct binder_error reply_error;
wait_queue_head_t wait;
struct binder_stats stats;
atomic_t tmp_ref;
bool is_dead;
};
/**
* struct binder_txn_fd_fixup - transaction fd fixup list element
* @fixup_entry: list entry
* @file: struct file to be associated with new fd
* @offset: offset in buffer data to this fixup
*
* List element for fd fixups in a transaction. Since file
* descriptors need to be allocated in the context of the
* target process, we pass each fd to be processed in this
* struct.
*/
struct binder_txn_fd_fixup {
struct list_head fixup_entry;
struct file *file;
size_t offset;
};
struct binder_transaction {
int debug_id;
struct binder_work work;
struct binder_thread *from;
struct binder_transaction *from_parent;
struct binder_proc *to_proc;
struct binder_thread *to_thread;
struct binder_transaction *to_parent;
unsigned need_reply:1;
/* unsigned is_dead:1; */ /* not used at the moment */
struct binder_buffer *buffer;
unsigned int code;
unsigned int flags;
long priority;
long saved_priority;
kuid_t sender_euid;
struct list_head fd_fixups;
/**
* @lock: protects @from, @to_proc, and @to_thread
*
* @from, @to_proc, and @to_thread can be set to NULL
* during thread teardown
*/
spinlock_t lock;
};
/**
* binder_proc_lock() - Acquire outer lock for given binder_proc
* @proc: struct binder_proc to acquire
*
* Acquires proc->outer_lock. Used to protect binder_ref
* structures associated with the given proc.
*/
#define binder_proc_lock(proc) _binder_proc_lock(proc, __LINE__)
static void
_binder_proc_lock(struct binder_proc *proc, int line)
__acquires(&proc->outer_lock)
{
binder_debug(BINDER_DEBUG_SPINLOCKS,
"%s: line=%d\n", __func__, line);
spin_lock(&proc->outer_lock);
}
/**
* binder_proc_unlock() - Release spinlock for given binder_proc
* @proc: struct binder_proc to acquire
*
* Release lock acquired via binder_proc_lock()
*/
#define binder_proc_unlock(_proc) _binder_proc_unlock(_proc, __LINE__)
static void
_binder_proc_unlock(struct binder_proc *proc, int line)
__releases(&proc->outer_lock)
{
binder_debug(BINDER_DEBUG_SPINLOCKS,
"%s: line=%d\n", __func__, line);
spin_unlock(&proc->outer_lock);
}
/**
* binder_inner_proc_lock() - Acquire inner lock for given binder_proc
* @proc: struct binder_proc to acquire
*
* Acquires proc->inner_lock. Used to protect todo lists
*/
#define binder_inner_proc_lock(proc) _binder_inner_proc_lock(proc, __LINE__)
static void
_binder_inner_proc_lock(struct binder_proc *proc, int line)
__acquires(&proc->inner_lock)
{
binder_debug(BINDER_DEBUG_SPINLOCKS,
"%s: line=%d\n", __func__, line);
spin_lock(&proc->inner_lock);
}
/**
* binder_inner_proc_unlock() - Release inner lock for given binder_proc
* @proc: struct binder_proc to acquire
*
* Release lock acquired via binder_inner_proc_lock()
*/
#define binder_inner_proc_unlock(proc) _binder_inner_proc_unlock(proc, __LINE__)
static void
_binder_inner_proc_unlock(struct binder_proc *proc, int line)
__releases(&proc->inner_lock)
{
binder_debug(BINDER_DEBUG_SPINLOCKS,
"%s: line=%d\n", __func__, line);
spin_unlock(&proc->inner_lock);
}
/**
* binder_node_lock() - Acquire spinlock for given binder_node
* @node: struct binder_node to acquire
*
* Acquires node->lock. Used to protect binder_node fields
*/
#define binder_node_lock(node) _binder_node_lock(node, __LINE__)
static void
_binder_node_lock(struct binder_node *node, int line)
__acquires(&node->lock)
{
binder_debug(BINDER_DEBUG_SPINLOCKS,
"%s: line=%d\n", __func__, line);
spin_lock(&node->lock);
}
/**
* binder_node_unlock() - Release spinlock for given binder_proc
* @node: struct binder_node to acquire
*
* Release lock acquired via binder_node_lock()
*/
#define binder_node_unlock(node) _binder_node_unlock(node, __LINE__)
static void
_binder_node_unlock(struct binder_node *node, int line)
__releases(&node->lock)
{
binder_debug(BINDER_DEBUG_SPINLOCKS,
"%s: line=%d\n", __func__, line);
spin_unlock(&node->lock);
}
/**
* binder_node_inner_lock() - Acquire node and inner locks
* @node: struct binder_node to acquire
*
* Acquires node->lock. If node->proc also acquires
* proc->inner_lock. Used to protect binder_node fields
*/
#define binder_node_inner_lock(node) _binder_node_inner_lock(node, __LINE__)
static void
_binder_node_inner_lock(struct binder_node *node, int line)
__acquires(&node->lock) __acquires(&node->proc->inner_lock)
{
binder_debug(BINDER_DEBUG_SPINLOCKS,
"%s: line=%d\n", __func__, line);
spin_lock(&node->lock);
if (node->proc)
binder_inner_proc_lock(node->proc);
else
/* annotation for sparse */
__acquire(&node->proc->inner_lock);
}
/**
* binder_node_unlock() - Release node and inner locks
* @node: struct binder_node to acquire
*
* Release lock acquired via binder_node_lock()
*/
#define binder_node_inner_unlock(node) _binder_node_inner_unlock(node, __LINE__)
static void
_binder_node_inner_unlock(struct binder_node *node, int line)
__releases(&node->lock) __releases(&node->proc->inner_lock)
{
struct binder_proc *proc = node->proc;
binder_debug(BINDER_DEBUG_SPINLOCKS,
"%s: line=%d\n", __func__, line);
if (proc)
binder_inner_proc_unlock(proc);
else
/* annotation for sparse */
__release(&node->proc->inner_lock);
spin_unlock(&node->lock);
}
static bool binder_worklist_empty_ilocked(struct list_head *list)
{
return list_empty(list);
}
/**
* binder_worklist_empty() - Check if no items on the work list
* @proc: binder_proc associated with list
* @list: list to check
*
* Return: true if there are no items on list, else false
*/
static bool binder_worklist_empty(struct binder_proc *proc,
struct list_head *list)
{
bool ret;
binder_inner_proc_lock(proc);
ret = binder_worklist_empty_ilocked(list);
binder_inner_proc_unlock(proc);
return ret;
}
/**
* binder_enqueue_work_ilocked() - Add an item to the work list
* @work: struct binder_work to add to list
* @target_list: list to add work to
*
* Adds the work to the specified list. Asserts that work
* is not already on a list.
*
* Requires the proc->inner_lock to be held.
*/
static void
binder_enqueue_work_ilocked(struct binder_work *work,
struct list_head *target_list)
{
BUG_ON(target_list == NULL);
BUG_ON(work->entry.next && !list_empty(&work->entry));
list_add_tail(&work->entry, target_list);
}
/**
* binder_enqueue_deferred_thread_work_ilocked() - Add deferred thread work
* @thread: thread to queue work to
* @work: struct binder_work to add to list
*
* Adds the work to the todo list of the thread. Doesn't set the process_todo
* flag, which means that (if it wasn't already set) the thread will go to
* sleep without handling this work when it calls read.
*
* Requires the proc->inner_lock to be held.
*/
static void
binder_enqueue_deferred_thread_work_ilocked(struct binder_thread *thread,
struct binder_work *work)
{
WARN_ON(!list_empty(&thread->waiting_thread_node));
binder_enqueue_work_ilocked(work, &thread->todo);
}
/**
* binder_enqueue_thread_work_ilocked() - Add an item to the thread work list
* @thread: thread to queue work to
* @work: struct binder_work to add to list
*
* Adds the work to the todo list of the thread, and enables processing
* of the todo queue.
*
* Requires the proc->inner_lock to be held.
*/
static void
binder_enqueue_thread_work_ilocked(struct binder_thread *thread,
struct binder_work *work)
{
WARN_ON(!list_empty(&thread->waiting_thread_node));
binder_enqueue_work_ilocked(work, &thread->todo);
thread->process_todo = true;
}
/**
* binder_enqueue_thread_work() - Add an item to the thread work list
* @thread: thread to queue work to
* @work: struct binder_work to add to list
*
* Adds the work to the todo list of the thread, and enables processing
* of the todo queue.
*/
static void
binder_enqueue_thread_work(struct binder_thread *thread,
struct binder_work *work)
{
binder_inner_proc_lock(thread->proc);
binder_enqueue_thread_work_ilocked(thread, work);
binder_inner_proc_unlock(thread->proc);
}
static void
binder_dequeue_work_ilocked(struct binder_work *work)
{
list_del_init(&work->entry);
}
/**
* binder_dequeue_work() - Removes an item from the work list
* @proc: binder_proc associated with list
* @work: struct binder_work to remove from list
*
* Removes the specified work item from whatever list it is on.
* Can safely be called if work is not on any list.
*/
static void
binder_dequeue_work(struct binder_proc *proc, struct binder_work *work)
{
binder_inner_proc_lock(proc);
binder_dequeue_work_ilocked(work);
binder_inner_proc_unlock(proc);
}
static struct binder_work *binder_dequeue_work_head_ilocked(
struct list_head *list)
{
struct binder_work *w;
w = list_first_entry_or_null(list, struct binder_work, entry);
if (w)
list_del_init(&w->entry);
return w;
}
/**
* binder_dequeue_work_head() - Dequeues the item at head of list
* @proc: binder_proc associated with list
* @list: list to dequeue head
*
* Removes the head of the list if there are items on the list
*
* Return: pointer dequeued binder_work, NULL if list was empty
*/
static struct binder_work *binder_dequeue_work_head(
struct binder_proc *proc,
struct list_head *list)
{
struct binder_work *w;
binder_inner_proc_lock(proc);
w = binder_dequeue_work_head_ilocked(list);
binder_inner_proc_unlock(proc);
return w;
}
static void
binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer);
static void binder_free_thread(struct binder_thread *thread);
static void binder_free_proc(struct binder_proc *proc);
static void binder_inc_node_tmpref_ilocked(struct binder_node *node);
static bool binder_has_work_ilocked(struct binder_thread *thread,
bool do_proc_work)
{
return thread->process_todo ||
thread->looper_need_return ||
(do_proc_work &&
!binder_worklist_empty_ilocked(&thread->proc->todo));
}
static bool binder_has_work(struct binder_thread *thread, bool do_proc_work)
{
bool has_work;
binder_inner_proc_lock(thread->proc);
has_work = binder_has_work_ilocked(thread, do_proc_work);
binder_inner_proc_unlock(thread->proc);
return has_work;
}
static bool binder_available_for_proc_work_ilocked(struct binder_thread *thread)
{
return !thread->transaction_stack &&
binder_worklist_empty_ilocked(&thread->todo) &&
(thread->looper & (BINDER_LOOPER_STATE_ENTERED |
BINDER_LOOPER_STATE_REGISTERED));
}
static void binder_wakeup_poll_threads_ilocked(struct binder_proc *proc,
bool sync)
{
struct rb_node *n;
struct binder_thread *thread;
for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) {
thread = rb_entry(n, struct binder_thread, rb_node);
if (thread->looper & BINDER_LOOPER_STATE_POLL &&
binder_available_for_proc_work_ilocked(thread)) {
if (sync)
wake_up_interruptible_sync(&thread->wait);
else
wake_up_interruptible(&thread->wait);
}
}
}
/**
* binder_select_thread_ilocked() - selects a thread for doing proc work.
* @proc: process to select a thread from
*
* Note that calling this function moves the thread off the waiting_threads
* list, so it can only be woken up by the caller of this function, or a
* signal. Therefore, callers *should* always wake up the thread this function
* returns.
*
* Return: If there's a thread currently waiting for process work,
* returns that thread. Otherwise returns NULL.
*/
static struct binder_thread *
binder_select_thread_ilocked(struct binder_proc *proc)
{
struct binder_thread *thread;
assert_spin_locked(&proc->inner_lock);
thread = list_first_entry_or_null(&proc->waiting_threads,
struct binder_thread,
waiting_thread_node);
if (thread)
list_del_init(&thread->waiting_thread_node);
return thread;
}
/**
* binder_wakeup_thread_ilocked() - wakes up a thread for doing proc work.
* @proc: process to wake up a thread in
* @thread: specific thread to wake-up (may be NULL)
* @sync: whether to do a synchronous wake-up
*
* This function wakes up a thread in the @proc process.
* The caller may provide a specific thread to wake-up in
* the @thread parameter. If @thread is NULL, this function
* will wake up threads that have called poll().
*
* Note that for this function to work as expected, callers
* should first call binder_select_thread() to find a thread
* to handle the work (if they don't have a thread already),
* and pass the result into the @thread parameter.
*/
static void binder_wakeup_thread_ilocked(struct binder_proc *proc,
struct binder_thread *thread,
bool sync)
{
assert_spin_locked(&proc->inner_lock);
if (thread) {
if (sync)
wake_up_interruptible_sync(&thread->wait);
else
wake_up_interruptible(&thread->wait);
return;
}
/* Didn't find a thread waiting for proc work; this can happen
* in two scenarios:
* 1. All threads are busy handling transactions
* In that case, one of those threads should call back into
* the kernel driver soon and pick up this work.
* 2. Threads are using the (e)poll interface, in which case
* they may be blocked on the waitqueue without having been
* added to waiting_threads. For this case, we just iterate
* over all threads not handling transaction work, and
* wake them all up. We wake all because we don't know whether
* a thread that called into (e)poll is handling non-binder
* work currently.
*/
binder_wakeup_poll_threads_ilocked(proc, sync);
}
static void binder_wakeup_proc_ilocked(struct binder_proc *proc)
{
struct binder_thread *thread = binder_select_thread_ilocked(proc);
binder_wakeup_thread_ilocked(proc, thread, /* sync = */false);
}
static void binder_set_nice(long nice)
{
long min_nice;
if (can_nice(current, nice)) {
set_user_nice(current, nice);
return;
}
min_nice = rlimit_to_nice(rlimit(RLIMIT_NICE));
binder_debug(BINDER_DEBUG_PRIORITY_CAP,
"%d: nice value %ld not allowed use %ld instead\n",
current->pid, nice, min_nice);
set_user_nice(current, min_nice);
if (min_nice <= MAX_NICE)
return;
binder_user_error("%d RLIMIT_NICE not set\n", current->pid);
}
static struct binder_node *binder_get_node_ilocked(struct binder_proc *proc,
binder_uintptr_t ptr)
{
struct rb_node *n = proc->nodes.rb_node;
struct binder_node *node;
assert_spin_locked(&proc->inner_lock);
while (n) {
node = rb_entry(n, struct binder_node, rb_node);
if (ptr < node->ptr)
n = n->rb_left;
else if (ptr > node->ptr)
n = n->rb_right;
else {
/*
* take an implicit weak reference
* to ensure node stays alive until
* call to binder_put_node()
*/
binder_inc_node_tmpref_ilocked(node);
return node;
}
}
return NULL;
}
static struct binder_node *binder_get_node(struct binder_proc *proc,
binder_uintptr_t ptr)
{
struct binder_node *node;
binder_inner_proc_lock(proc);
node = binder_get_node_ilocked(proc, ptr);
binder_inner_proc_unlock(proc);
return node;
}
static struct binder_node *binder_init_node_ilocked(
struct binder_proc *proc,
struct binder_node *new_node,
struct flat_binder_object *fp)
{
struct rb_node **p = &proc->nodes.rb_node;
struct rb_node *parent = NULL;
struct binder_node *node;
binder_uintptr_t ptr = fp ? fp->binder : 0;
binder_uintptr_t cookie = fp ? fp->cookie : 0;
__u32 flags = fp ? fp->flags : 0;
assert_spin_locked(&proc->inner_lock);
while (*p) {
parent = *p;
node = rb_entry(parent, struct binder_node, rb_node);
if (ptr < node->ptr)
p = &(*p)->rb_left;
else if (ptr > node->ptr)
p = &(*p)->rb_right;
else {
/*
* A matching node is already in
* the rb tree. Abandon the init
* and return it.
*/
binder_inc_node_tmpref_ilocked(node);
return node;
}
}
node = new_node;
binder_stats_created(BINDER_STAT_NODE);
node->tmp_refs++;
rb_link_node(&node->rb_node, parent, p);
rb_insert_color(&node->rb_node, &proc->nodes);
node->debug_id = atomic_inc_return(&binder_last_id);
node->proc = proc;
node->ptr = ptr;
node->cookie = cookie;
node->work.type = BINDER_WORK_NODE;
node->min_priority = flags & FLAT_BINDER_FLAG_PRIORITY_MASK;
node->accept_fds = !!(flags & FLAT_BINDER_FLAG_ACCEPTS_FDS);
spin_lock_init(&node->lock);
INIT_LIST_HEAD(&node->work.entry);
INIT_LIST_HEAD(&node->async_todo);
binder_debug(BINDER_DEBUG_INTERNAL_REFS,
"%d:%d node %d u%016llx c%016llx created\n",
proc->pid, current->pid, node->debug_id,
(u64)node->ptr, (u64)node->cookie);
return node;
}
static struct binder_node *binder_new_node(struct binder_proc *proc,
struct flat_binder_object *fp)
{
struct binder_node *node;
struct binder_node *new_node = kzalloc(sizeof(*node), GFP_KERNEL);
if (!new_node)
return NULL;
binder_inner_proc_lock(proc);
node = binder_init_node_ilocked(proc, new_node, fp);
binder_inner_proc_unlock(proc);
if (node != new_node)
/*
* The node was already added by another thread
*/
kfree(new_node);
return node;
}
static void binder_free_node(struct binder_node *node)
{
kfree(node);
binder_stats_deleted(BINDER_STAT_NODE);
}
static int binder_inc_node_nilocked(struct binder_node *node, int strong,
int internal,
struct list_head *target_list)
{
struct binder_proc *proc = node->proc;
assert_spin_locked(&node->lock);
if (proc)
assert_spin_locked(&proc->inner_lock);
if (strong) {
if (internal) {
if (target_list == NULL &&
node->internal_strong_refs == 0 &&
!(node->proc &&
node == node->proc->context->binder_context_mgr_node &&
node->has_strong_ref)) {
pr_err("invalid inc strong node for %d\n",
node->debug_id);
return -EINVAL;
}
node->internal_strong_refs++;
} else
node->local_strong_refs++;
if (!node->has_strong_ref && target_list) {
struct binder_thread *thread = container_of(target_list,
struct binder_thread, todo);
binder_dequeue_work_ilocked(&node->work);
BUG_ON(&thread->todo != target_list);
binder_enqueue_deferred_thread_work_ilocked(thread,
&node->work);
}
} else {
if (!internal)
node->local_weak_refs++;
if (!node->has_weak_ref && list_empty(&node->work.entry)) {
if (target_list == NULL) {
pr_err("invalid inc weak node for %d\n",
node->debug_id);
return -EINVAL;
}
/*
* See comment above
*/
binder_enqueue_work_ilocked(&node->work, target_list);
}
}
return 0;
}
static int binder_inc_node(struct binder_node *node, int strong, int internal,
struct list_head *target_list)
{
int ret;
binder_node_inner_lock(node);
ret = binder_inc_node_nilocked(node, strong, internal, target_list);
binder_node_inner_unlock(node);
return ret;
}
static bool binder_dec_node_nilocked(struct binder_node *node,
int strong, int internal)
{
struct binder_proc *proc = node->proc;
assert_spin_locked(&node->lock);
if (proc)
assert_spin_locked(&proc->inner_lock);
if (strong) {
if (internal)
node->internal_strong_refs--;
else
node->local_strong_refs--;
if (node->local_strong_refs || node->internal_strong_refs)
return false;
} else {
if (!internal)
node->local_weak_refs--;
if (node->local_weak_refs || node->tmp_refs ||
!hlist_empty(&node->refs))
return false;
}
if (proc && (node->has_strong_ref || node->has_weak_ref)) {
if (list_empty(&node->work.entry)) {
binder_enqueue_work_ilocked(&node->work, &proc->todo);
binder_wakeup_proc_ilocked(proc);
}
} else {
if (hlist_empty(&node->refs) && !node->local_strong_refs &&
!node->local_weak_refs && !node->tmp_refs) {
if (proc) {
binder_dequeue_work_ilocked(&node->work);
rb_erase(&node->rb_node, &proc->nodes);
binder_debug(BINDER_DEBUG_INTERNAL_REFS,
"refless node %d deleted\n",
node->debug_id);
} else {
BUG_ON(!list_empty(&node->work.entry));
spin_lock(&binder_dead_nodes_lock);
/*
* tmp_refs could have changed so
* check it again
*/
if (node->tmp_refs) {
spin_unlock(&binder_dead_nodes_lock);
return false;
}
hlist_del(&node->dead_node);
spin_unlock(&binder_dead_nodes_lock);
binder_debug(BINDER_DEBUG_INTERNAL_REFS,
"dead node %d deleted\n",
node->debug_id);
}
return true;
}
}
return false;
}
static void binder_dec_node(struct binder_node *node, int strong, int internal)
{
bool free_node;
binder_node_inner_lock(node);
free_node = binder_dec_node_nilocked(node, strong, internal);
binder_node_inner_unlock(node);
if (free_node)
binder_free_node(node);
}
static void binder_inc_node_tmpref_ilocked(struct binder_node *node)
{
/*
* No call to binder_inc_node() is needed since we
* don't need to inform userspace of any changes to
* tmp_refs
*/
node->tmp_refs++;
}
/**
* binder_inc_node_tmpref() - take a temporary reference on node
* @node: node to reference
*
* Take reference on node to prevent the node from being freed
* while referenced only by a local variable. The inner lock is
* needed to serialize with the node work on the queue (which
* isn't needed after the node is dead). If the node is dead
* (node->proc is NULL), use binder_dead_nodes_lock to protect
* node->tmp_refs against dead-node-only cases where the node
* lock cannot be acquired (eg traversing the dead node list to
* print nodes)
*/
static void binder_inc_node_tmpref(struct binder_node *node)
{
binder_node_lock(node);
if (node->proc)
binder_inner_proc_lock(node->proc);
else
spin_lock(&binder_dead_nodes_lock);
binder_inc_node_tmpref_ilocked(node);
if (node->proc)
binder_inner_proc_unlock(node->proc);
else
spin_unlock(&binder_dead_nodes_lock);
binder_node_unlock(node);
}
/**
* binder_dec_node_tmpref() - remove a temporary reference on node
* @node: node to reference
*
* Release temporary reference on node taken via binder_inc_node_tmpref()
*/
static void binder_dec_node_tmpref(struct binder_node *node)
{
bool free_node;
binder_node_inner_lock(node);
if (!node->proc)
spin_lock(&binder_dead_nodes_lock);
else
__acquire(&binder_dead_nodes_lock);
node->tmp_refs--;
BUG_ON(node->tmp_refs < 0);
if (!node->proc)
spin_unlock(&binder_dead_nodes_lock);
else
__release(&binder_dead_nodes_lock);
/*
* Call binder_dec_node() to check if all refcounts are 0
* and cleanup is needed. Calling with strong=0 and internal=1
* causes no actual reference to be released in binder_dec_node().
* If that changes, a change is needed here too.
*/
free_node = binder_dec_node_nilocked(node, 0, 1);
binder_node_inner_unlock(node);
if (free_node)
binder_free_node(node);
}
static void binder_put_node(struct binder_node *node)
{
binder_dec_node_tmpref(node);
}
static struct binder_ref *binder_get_ref_olocked(struct binder_proc *proc,
u32 desc, bool need_strong_ref)
{
struct rb_node *n = proc->refs_by_desc.rb_node;
struct binder_ref *ref;
while (n) {
ref = rb_entry(n, struct binder_ref, rb_node_desc);
if (desc < ref->data.desc) {
n = n->rb_left;
} else if (desc > ref->data.desc) {
n = n->rb_right;
} else if (need_strong_ref && !ref->data.strong) {
binder_user_error("tried to use weak ref as strong ref\n");
return NULL;
} else {
return ref;
}
}
return NULL;
}
/**
* binder_get_ref_for_node_olocked() - get the ref associated with given node
* @proc: binder_proc that owns the ref
* @node: binder_node of target
* @new_ref: newly allocated binder_ref to be initialized or %NULL
*
* Look up the ref for the given node and return it if it exists
*
* If it doesn't exist and the caller provides a newly allocated
* ref, initialize the fields of the newly allocated ref and insert
* into the given proc rb_trees and node refs list.
*
* Return: the ref for node. It is possible that another thread
* allocated/initialized the ref first in which case the
* returned ref would be different than the passed-in
* new_ref. new_ref must be kfree'd by the caller in
* this case.
*/
static struct binder_ref *binder_get_ref_for_node_olocked(
struct binder_proc *proc,
struct binder_node *node,
struct binder_ref *new_ref)
{
struct binder_context *context = proc->context;
struct rb_node **p = &proc->refs_by_node.rb_node;
struct rb_node *parent = NULL;
struct binder_ref *ref;
struct rb_node *n;
while (*p) {
parent = *p;
ref = rb_entry(parent, struct binder_ref, rb_node_node);
if (node < ref->node)
p = &(*p)->rb_left;
else if (node > ref->node)
p = &(*p)->rb_right;
else
return ref;
}
if (!new_ref)
return NULL;
binder_stats_created(BINDER_STAT_REF);
new_ref->data.debug_id = atomic_inc_return(&binder_last_id);
new_ref->proc = proc;
new_ref->node = node;
rb_link_node(&new_ref->rb_node_node, parent, p);
rb_insert_color(&new_ref->rb_node_node, &proc->refs_by_node);
new_ref->data.desc = (node == context->binder_context_mgr_node) ? 0 : 1;
for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) {
ref = rb_entry(n, struct binder_ref, rb_node_desc);
if (ref->data.desc > new_ref->data.desc)
break;
new_ref->data.desc = ref->data.desc + 1;
}
p = &proc->refs_by_desc.rb_node;
while (*p) {
parent = *p;
ref = rb_entry(parent, struct binder_ref, rb_node_desc);
if (new_ref->data.desc < ref->data.desc)
p = &(*p)->rb_left;
else if (new_ref->data.desc > ref->data.desc)
p = &(*p)->rb_right;
else
BUG();
}
rb_link_node(&new_ref->rb_node_desc, parent, p);
rb_insert_color(&new_ref->rb_node_desc, &proc->refs_by_desc);
binder_node_lock(node);
hlist_add_head(&new_ref->node_entry, &node->refs);
binder_debug(BINDER_DEBUG_INTERNAL_REFS,
"%d new ref %d desc %d for node %d\n",
proc->pid, new_ref->data.debug_id, new_ref->data.desc,
node->debug_id);
binder_node_unlock(node);
return new_ref;
}
static void binder_cleanup_ref_olocked(struct binder_ref *ref)
{
bool delete_node = false;
binder_debug(BINDER_DEBUG_INTERNAL_REFS,
"%d delete ref %d desc %d for node %d\n",
ref->proc->pid, ref->data.debug_id, ref->data.desc,
ref->node->debug_id);
rb_erase(&ref->rb_node_desc, &ref->proc->refs_by_desc);
rb_erase(&ref->rb_node_node, &ref->proc->refs_by_node);
binder_node_inner_lock(ref->node);
if (ref->data.strong)
binder_dec_node_nilocked(ref->node, 1, 1);
hlist_del(&ref->node_entry);
delete_node = binder_dec_node_nilocked(ref->node, 0, 1);
binder_node_inner_unlock(ref->node);
/*
* Clear ref->node unless we want the caller to free the node
*/
if (!delete_node) {
/*
* The caller uses ref->node to determine
* whether the node needs to be freed. Clear
* it since the node is still alive.
*/
ref->node = NULL;
}
if (ref->death) {
binder_debug(BINDER_DEBUG_DEAD_BINDER,
"%d delete ref %d desc %d has death notification\n",
ref->proc->pid, ref->data.debug_id,
ref->data.desc);
binder_dequeue_work(ref->proc, &ref->death->work);
binder_stats_deleted(BINDER_STAT_DEATH);
}
binder_stats_deleted(BINDER_STAT_REF);
}
/**
* binder_inc_ref_olocked() - increment the ref for given handle
* @ref: ref to be incremented
* @strong: if true, strong increment, else weak
* @target_list: list to queue node work on
*
* Increment the ref. @ref->proc->outer_lock must be held on entry
*
* Return: 0, if successful, else errno
*/
static int binder_inc_ref_olocked(struct binder_ref *ref, int strong,
struct list_head *target_list)
{
int ret;
if (strong) {
if (ref->data.strong == 0) {
ret = binder_inc_node(ref->node, 1, 1, target_list);
if (ret)
return ret;
}
ref->data.strong++;
} else {
if (ref->data.weak == 0) {
ret = binder_inc_node(ref->node, 0, 1, target_list);
if (ret)
return ret;
}
ref->data.weak++;
}
return 0;
}
/**
* binder_dec_ref() - dec the ref for given handle
* @ref: ref to be decremented
* @strong: if true, strong decrement, else weak
*
* Decrement the ref.
*
* Return: true if ref is cleaned up and ready to be freed
*/
static bool binder_dec_ref_olocked(struct binder_ref *ref, int strong)
{
if (strong) {
if (ref->data.strong == 0) {
binder_user_error("%d invalid dec strong, ref %d desc %d s %d w %d\n",
ref->proc->pid, ref->data.debug_id,
ref->data.desc, ref->data.strong,
ref->data.weak);
return false;
}
ref->data.strong--;
if (ref->data.strong == 0)
binder_dec_node(ref->node, strong, 1);
} else {
if (ref->data.weak == 0) {
binder_user_error("%d invalid dec weak, ref %d desc %d s %d w %d\n",
ref->proc->pid, ref->data.debug_id,
ref->data.desc, ref->data.strong,
ref->data.weak);
return false;
}
ref->data.weak--;
}
if (ref->data.strong == 0 && ref->data.weak == 0) {
binder_cleanup_ref_olocked(ref);
return true;
}
return false;
}
/**
* binder_get_node_from_ref() - get the node from the given proc/desc
* @proc: proc containing the ref
* @desc: the handle associated with the ref
* @need_strong_ref: if true, only return node if ref is strong
* @rdata: the id/refcount data for the ref
*
* Given a proc and ref handle, return the associated binder_node
*
* Return: a binder_node or NULL if not found or not strong when strong required
*/
static struct binder_node *binder_get_node_from_ref(
struct binder_proc *proc,
u32 desc, bool need_strong_ref,
struct binder_ref_data *rdata)
{
struct binder_node *node;
struct binder_ref *ref;
binder_proc_lock(proc);
ref = binder_get_ref_olocked(proc, desc, need_strong_ref);
if (!ref)
goto err_no_ref;
node = ref->node;
/*
* Take an implicit reference on the node to ensure
* it stays alive until the call to binder_put_node()
*/
binder_inc_node_tmpref(node);
if (rdata)
*rdata = ref->data;
binder_proc_unlock(proc);
return node;
err_no_ref:
binder_proc_unlock(proc);
return NULL;
}
/**
* binder_free_ref() - free the binder_ref
* @ref: ref to free
*
* Free the binder_ref. Free the binder_node indicated by ref->node
* (if non-NULL) and the binder_ref_death indicated by ref->death.
*/
static void binder_free_ref(struct binder_ref *ref)
{
if (ref->node)
binder_free_node(ref->node);
kfree(ref->death);
kfree(ref);
}
/**
* binder_update_ref_for_handle() - inc/dec the ref for given handle
* @proc: proc containing the ref
* @desc: the handle associated with the ref
* @increment: true=inc reference, false=dec reference
* @strong: true=strong reference, false=weak reference
* @rdata: the id/refcount data for the ref
*
* Given a proc and ref handle, increment or decrement the ref
* according to "increment" arg.
*
* Return: 0 if successful, else errno
*/
static int binder_update_ref_for_handle(struct binder_proc *proc,
uint32_t desc, bool increment, bool strong,
struct binder_ref_data *rdata)
{
int ret = 0;
struct binder_ref *ref;
bool delete_ref = false;
binder_proc_lock(proc);
ref = binder_get_ref_olocked(proc, desc, strong);
if (!ref) {
ret = -EINVAL;
goto err_no_ref;
}
if (increment)
ret = binder_inc_ref_olocked(ref, strong, NULL);
else
delete_ref = binder_dec_ref_olocked(ref, strong);
if (rdata)
*rdata = ref->data;
binder_proc_unlock(proc);
if (delete_ref)
binder_free_ref(ref);
return ret;
err_no_ref:
binder_proc_unlock(proc);
return ret;
}
/**
* binder_dec_ref_for_handle() - dec the ref for given handle
* @proc: proc containing the ref
* @desc: the handle associated with the ref
* @strong: true=strong reference, false=weak reference
* @rdata: the id/refcount data for the ref
*
* Just calls binder_update_ref_for_handle() to decrement the ref.
*
* Return: 0 if successful, else errno
*/
static int binder_dec_ref_for_handle(struct binder_proc *proc,
uint32_t desc, bool strong, struct binder_ref_data *rdata)
{
return binder_update_ref_for_handle(proc, desc, false, strong, rdata);
}
/**
* binder_inc_ref_for_node() - increment the ref for given proc/node
* @proc: proc containing the ref
* @node: target node
* @strong: true=strong reference, false=weak reference
* @target_list: worklist to use if node is incremented
* @rdata: the id/refcount data for the ref
*
* Given a proc and node, increment the ref. Create the ref if it
* doesn't already exist
*
* Return: 0 if successful, else errno
*/
static int binder_inc_ref_for_node(struct binder_proc *proc,
struct binder_node *node,
bool strong,
struct list_head *target_list,
struct binder_ref_data *rdata)
{
struct binder_ref *ref;
struct binder_ref *new_ref = NULL;
int ret = 0;
binder_proc_lock(proc);
ref = binder_get_ref_for_node_olocked(proc, node, NULL);
if (!ref) {
binder_proc_unlock(proc);
new_ref = kzalloc(sizeof(*ref), GFP_KERNEL);
if (!new_ref)
return -ENOMEM;
binder_proc_lock(proc);
ref = binder_get_ref_for_node_olocked(proc, node, new_ref);
}
ret = binder_inc_ref_olocked(ref, strong, target_list);
*rdata = ref->data;
binder_proc_unlock(proc);
if (new_ref && ref != new_ref)
/*
* Another thread created the ref first so
* free the one we allocated
*/
kfree(new_ref);
return ret;
}
static void binder_pop_transaction_ilocked(struct binder_thread *target_thread,
struct binder_transaction *t)
{
BUG_ON(!target_thread);
assert_spin_locked(&target_thread->proc->inner_lock);
BUG_ON(target_thread->transaction_stack != t);
BUG_ON(target_thread->transaction_stack->from != target_thread);
target_thread->transaction_stack =
target_thread->transaction_stack->from_parent;
t->from = NULL;
}
/**
* binder_thread_dec_tmpref() - decrement thread->tmp_ref
* @thread: thread to decrement
*
* A thread needs to be kept alive while being used to create or
* handle a transaction. binder_get_txn_from() is used to safely
* extract t->from from a binder_transaction and keep the thread
* indicated by t->from from being freed. When done with that
* binder_thread, this function is called to decrement the
* tmp_ref and free if appropriate (thread has been released
* and no transaction being processed by the driver)
*/
static void binder_thread_dec_tmpref(struct binder_thread *thread)
{
/*
* atomic is used to protect the counter value while
* it cannot reach zero or thread->is_dead is false
*/
binder_inner_proc_lock(thread->proc);
atomic_dec(&thread->tmp_ref);
if (thread->is_dead && !atomic_read(&thread->tmp_ref)) {
binder_inner_proc_unlock(thread->proc);
binder_free_thread(thread);
return;
}
binder_inner_proc_unlock(thread->proc);
}
/**
* binder_proc_dec_tmpref() - decrement proc->tmp_ref
* @proc: proc to decrement
*
* A binder_proc needs to be kept alive while being used to create or
* handle a transaction. proc->tmp_ref is incremented when
* creating a new transaction or the binder_proc is currently in-use
* by threads that are being released. When done with the binder_proc,
* this function is called to decrement the counter and free the
* proc if appropriate (proc has been released, all threads have
* been released and not currenly in-use to process a transaction).
*/
static void binder_proc_dec_tmpref(struct binder_proc *proc)
{
binder_inner_proc_lock(proc);
proc->tmp_ref--;
if (proc->is_dead && RB_EMPTY_ROOT(&proc->threads) &&
!proc->tmp_ref) {
binder_inner_proc_unlock(proc);
binder_free_proc(proc);
return;
}
binder_inner_proc_unlock(proc);
}
/**
* binder_get_txn_from() - safely extract the "from" thread in transaction
* @t: binder transaction for t->from
*
* Atomically return the "from" thread and increment the tmp_ref
* count for the thread to ensure it stays alive until
* binder_thread_dec_tmpref() is called.
*
* Return: the value of t->from
*/
static struct binder_thread *binder_get_txn_from(
struct binder_transaction *t)
{
struct binder_thread *from;
spin_lock(&t->lock);
from = t->from;
if (from)
atomic_inc(&from->tmp_ref);
spin_unlock(&t->lock);
return from;
}
/**
* binder_get_txn_from_and_acq_inner() - get t->from and acquire inner lock
* @t: binder transaction for t->from
*
* Same as binder_get_txn_from() except it also acquires the proc->inner_lock
* to guarantee that the thread cannot be released while operating on it.
* The caller must call binder_inner_proc_unlock() to release the inner lock
* as well as call binder_dec_thread_txn() to release the reference.
*
* Return: the value of t->from
*/
static struct binder_thread *binder_get_txn_from_and_acq_inner(
struct binder_transaction *t)
__acquires(&t->from->proc->inner_lock)
{
struct binder_thread *from;
from = binder_get_txn_from(t);
if (!from) {
__acquire(&from->proc->inner_lock);
return NULL;
}
binder_inner_proc_lock(from->proc);
if (t->from) {
BUG_ON(from != t->from);
return from;
}
binder_inner_proc_unlock(from->proc);
__acquire(&from->proc->inner_lock);
binder_thread_dec_tmpref(from);
return NULL;
}
/**
* binder_free_txn_fixups() - free unprocessed fd fixups
* @t: binder transaction for t->from
*
* If the transaction is being torn down prior to being
* processed by the target process, free all of the
* fd fixups and fput the file structs. It is safe to
* call this function after the fixups have been
* processed -- in that case, the list will be empty.
*/
static void binder_free_txn_fixups(struct binder_transaction *t)
{
struct binder_txn_fd_fixup *fixup, *tmp;
list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
fput(fixup->file);
list_del(&fixup->fixup_entry);
kfree(fixup);
}
}
static void binder_free_transaction(struct binder_transaction *t)
{
if (t->buffer)
t->buffer->transaction = NULL;
binder_free_txn_fixups(t);
kfree(t);
binder_stats_deleted(BINDER_STAT_TRANSACTION);
}
static void binder_send_failed_reply(struct binder_transaction *t,
uint32_t error_code)
{
struct binder_thread *target_thread;
struct binder_transaction *next;
BUG_ON(t->flags & TF_ONE_WAY);
while (1) {
target_thread = binder_get_txn_from_and_acq_inner(t);
if (target_thread) {
binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
"send failed reply for transaction %d to %d:%d\n",
t->debug_id,
target_thread->proc->pid,
target_thread->pid);
binder_pop_transaction_ilocked(target_thread, t);
if (target_thread->reply_error.cmd == BR_OK) {
target_thread->reply_error.cmd = error_code;
binder_enqueue_thread_work_ilocked(
target_thread,
&target_thread->reply_error.work);
wake_up_interruptible(&target_thread->wait);
} else {
/*
* Cannot get here for normal operation, but
* we can if multiple synchronous transactions
* are sent without blocking for responses.
* Just ignore the 2nd error in this case.
*/
pr_warn("Unexpected reply error: %u\n",
target_thread->reply_error.cmd);
}
binder_inner_proc_unlock(target_thread->proc);
binder_thread_dec_tmpref(target_thread);
binder_free_transaction(t);
return;
} else {
__release(&target_thread->proc->inner_lock);
}
next = t->from_parent;
binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
"send failed reply for transaction %d, target dead\n",
t->debug_id);
binder_free_transaction(t);
if (next == NULL) {
binder_debug(BINDER_DEBUG_DEAD_BINDER,
"reply failed, no target thread at root\n");
return;
}
t = next;
binder_debug(BINDER_DEBUG_DEAD_BINDER,
"reply failed, no target thread -- retry %d\n",
t->debug_id);
}
}
/**
* binder_cleanup_transaction() - cleans up undelivered transaction
* @t: transaction that needs to be cleaned up
* @reason: reason the transaction wasn't delivered
* @error_code: error to return to caller (if synchronous call)
*/
static void binder_cleanup_transaction(struct binder_transaction *t,
const char *reason,
uint32_t error_code)
{
if (t->buffer->target_node && !(t->flags & TF_ONE_WAY)) {
binder_send_failed_reply(t, error_code);
} else {
binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
"undelivered transaction %d, %s\n",
t->debug_id, reason);
binder_free_transaction(t);
}
}
/**
* binder_validate_object() - checks for a valid metadata object in a buffer.
* @buffer: binder_buffer that we're parsing.
* @offset: offset in the buffer at which to validate an object.
*
* Return: If there's a valid metadata object at @offset in @buffer, the
* size of that object. Otherwise, it returns zero.
*/
static size_t binder_validate_object(struct binder_buffer *buffer, u64 offset)
{
/* Check if we can read a header first */
struct binder_object_header *hdr;
size_t object_size = 0;
if (buffer->data_size < sizeof(*hdr) ||
offset > buffer->data_size - sizeof(*hdr) ||
!IS_ALIGNED(offset, sizeof(u32)))
return 0;
/* Ok, now see if we can read a complete object. */
hdr = (struct binder_object_header *)(buffer->data + offset);
switch (hdr->type) {
case BINDER_TYPE_BINDER:
case BINDER_TYPE_WEAK_BINDER:
case BINDER_TYPE_HANDLE:
case BINDER_TYPE_WEAK_HANDLE:
object_size = sizeof(struct flat_binder_object);
break;
case BINDER_TYPE_FD:
object_size = sizeof(struct binder_fd_object);
break;
case BINDER_TYPE_PTR:
object_size = sizeof(struct binder_buffer_object);
break;
case BINDER_TYPE_FDA:
object_size = sizeof(struct binder_fd_array_object);
break;
default:
return 0;
}
if (offset <= buffer->data_size - object_size &&
buffer->data_size >= object_size)
return object_size;
else
return 0;
}
/**
* binder_validate_ptr() - validates binder_buffer_object in a binder_buffer.
* @b: binder_buffer containing the object
* @index: index in offset array at which the binder_buffer_object is
* located
* @start: points to the start of the offset array
* @num_valid: the number of valid offsets in the offset array
*
* Return: If @index is within the valid range of the offset array
* described by @start and @num_valid, and if there's a valid
* binder_buffer_object at the offset found in index @index
* of the offset array, that object is returned. Otherwise,
* %NULL is returned.
* Note that the offset found in index @index itself is not
* verified; this function assumes that @num_valid elements
* from @start were previously verified to have valid offsets.
*/
static struct binder_buffer_object *binder_validate_ptr(struct binder_buffer *b,
binder_size_t index,
binder_size_t *start,
binder_size_t num_valid)
{
struct binder_buffer_object *buffer_obj;
binder_size_t *offp;
if (index >= num_valid)
return NULL;
offp = start + index;
buffer_obj = (struct binder_buffer_object *)(b->data + *offp);
if (buffer_obj->hdr.type != BINDER_TYPE_PTR)
return NULL;
return buffer_obj;
}
/**
* binder_validate_fixup() - validates pointer/fd fixups happen in order.
* @b: transaction buffer
* @objects_start start of objects buffer
* @buffer: binder_buffer_object in which to fix up
* @offset: start offset in @buffer to fix up
* @last_obj: last binder_buffer_object that we fixed up in
* @last_min_offset: minimum fixup offset in @last_obj
*
* Return: %true if a fixup in buffer @buffer at offset @offset is
* allowed.
*
* For safety reasons, we only allow fixups inside a buffer to happen
* at increasing offsets; additionally, we only allow fixup on the last
* buffer object that was verified, or one of its parents.
*
* Example of what is allowed:
*
* A
* B (parent = A, offset = 0)
* C (parent = A, offset = 16)
* D (parent = C, offset = 0)
* E (parent = A, offset = 32) // min_offset is 16 (C.parent_offset)
*
* Examples of what is not allowed:
*
* Decreasing offsets within the same parent:
* A
* C (parent = A, offset = 16)
* B (parent = A, offset = 0) // decreasing offset within A
*
* Referring to a parent that wasn't the last object or any of its parents:
* A
* B (parent = A, offset = 0)
* C (parent = A, offset = 0)
* C (parent = A, offset = 16)
* D (parent = B, offset = 0) // B is not A or any of A's parents
*/
static bool binder_validate_fixup(struct binder_buffer *b,
binder_size_t *objects_start,
struct binder_buffer_object *buffer,
binder_size_t fixup_offset,
struct binder_buffer_object *last_obj,
binder_size_t last_min_offset)
{
if (!last_obj) {
/* Nothing to fix up in */
return false;
}
while (last_obj != buffer) {
/*
* Safe to retrieve the parent of last_obj, since it
* was already previously verified by the driver.
*/
if ((last_obj->flags & BINDER_BUFFER_FLAG_HAS_PARENT) == 0)
return false;
last_min_offset = last_obj->parent_offset + sizeof(uintptr_t);
last_obj = (struct binder_buffer_object *)
(b->data + *(objects_start + last_obj->parent));
}
return (fixup_offset >= last_min_offset);
}
/**
* struct binder_task_work_cb - for deferred close
*
* @twork: callback_head for task work
* @fd: fd to close
*
* Structure to pass task work to be handled after
* returning from binder_ioctl() via task_work_add().
*/
struct binder_task_work_cb {
struct callback_head twork;
struct file *file;
};
/**
* binder_do_fd_close() - close list of file descriptors
* @twork: callback head for task work
*
* It is not safe to call ksys_close() during the binder_ioctl()
* function if there is a chance that binder's own file descriptor
* might be closed. This is to meet the requirements for using
* fdget() (see comments for __fget_light()). Therefore use
* task_work_add() to schedule the close operation once we have
* returned from binder_ioctl(). This function is a callback
* for that mechanism and does the actual ksys_close() on the
* given file descriptor.
*/
static void binder_do_fd_close(struct callback_head *twork)
{
struct binder_task_work_cb *twcb = container_of(twork,
struct binder_task_work_cb, twork);
fput(twcb->file);
kfree(twcb);
}
/**
* binder_deferred_fd_close() - schedule a close for the given file-descriptor
* @fd: file-descriptor to close
*
* See comments in binder_do_fd_close(). This function is used to schedule
* a file-descriptor to be closed after returning from binder_ioctl().
*/
static void binder_deferred_fd_close(int fd)
{
struct binder_task_work_cb *twcb;
twcb = kzalloc(sizeof(*twcb), GFP_KERNEL);
if (!twcb)
return;
init_task_work(&twcb->twork, binder_do_fd_close);
__close_fd_get_file(fd, &twcb->file);
if (twcb->file)
task_work_add(current, &twcb->twork, true);
else
kfree(twcb);
}
static void binder_transaction_buffer_release(struct binder_proc *proc,
struct binder_buffer *buffer,
binder_size_t *failed_at)
{
binder_size_t *offp, *off_start, *off_end;
int debug_id = buffer->debug_id;
binder_debug(BINDER_DEBUG_TRANSACTION,
"%d buffer release %d, size %zd-%zd, failed at %pK\n",
proc->pid, buffer->debug_id,
buffer->data_size, buffer->offsets_size, failed_at);
if (buffer->target_node)
binder_dec_node(buffer->target_node, 1, 0);
off_start = (binder_size_t *)(buffer->data +
ALIGN(buffer->data_size, sizeof(void *)));
if (failed_at)
off_end = failed_at;
else
off_end = (void *)off_start + buffer->offsets_size;
for (offp = off_start; offp < off_end; offp++) {
struct binder_object_header *hdr;
size_t object_size = binder_validate_object(buffer, *offp);
if (object_size == 0) {
pr_err("transaction release %d bad object at offset %lld, size %zd\n",
debug_id, (u64)*offp, buffer->data_size);
continue;
}
hdr = (struct binder_object_header *)(buffer->data + *offp);
switch (hdr->type) {
case BINDER_TYPE_BINDER:
case BINDER_TYPE_WEAK_BINDER: {
struct flat_binder_object *fp;
struct binder_node *node;
fp = to_flat_binder_object(hdr);
node = binder_get_node(proc, fp->binder);
if (node == NULL) {
pr_err("transaction release %d bad node %016llx\n",
debug_id, (u64)fp->binder);
break;
}
binder_debug(BINDER_DEBUG_TRANSACTION,
" node %d u%016llx\n",
node->debug_id, (u64)node->ptr);
binder_dec_node(node, hdr->type == BINDER_TYPE_BINDER,
0);
binder_put_node(node);
} break;
case BINDER_TYPE_HANDLE:
case BINDER_TYPE_WEAK_HANDLE: {
struct flat_binder_object *fp;
struct binder_ref_data rdata;
int ret;
fp = to_flat_binder_object(hdr);
ret = binder_dec_ref_for_handle(proc, fp->handle,
hdr->type == BINDER_TYPE_HANDLE, &rdata);
if (ret) {
pr_err("transaction release %d bad handle %d, ret = %d\n",
debug_id, fp->handle, ret);
break;
}
binder_debug(BINDER_DEBUG_TRANSACTION,
" ref %d desc %d\n",
rdata.debug_id, rdata.desc);
} break;
case BINDER_TYPE_FD: {
/*
* No need to close the file here since user-space
* closes it for for successfully delivered
* transactions. For transactions that weren't
* delivered, the new fd was never allocated so
* there is no need to close and the fput on the
* file is done when the transaction is torn
* down.
*/
WARN_ON(failed_at &&
proc->tsk == current->group_leader);
} break;
case BINDER_TYPE_PTR:
/*
* Nothing to do here, this will get cleaned up when the
* transaction buffer gets freed
*/
break;
case BINDER_TYPE_FDA: {
struct binder_fd_array_object *fda;
struct binder_buffer_object *parent;
uintptr_t parent_buffer;
u32 *fd_array;
size_t fd_index;
binder_size_t fd_buf_size;
if (proc->tsk != current->group_leader) {
/*
* Nothing to do if running in sender context
* The fd fixups have not been applied so no
* fds need to be closed.
*/
continue;
}
fda = to_binder_fd_array_object(hdr);
parent = binder_validate_ptr(buffer, fda->parent,
off_start,
offp - off_start);
if (!parent) {
pr_err("transaction release %d bad parent offset\n",
debug_id);
continue;
}
/*
* Since the parent was already fixed up, convert it
* back to kernel address space to access it
*/
parent_buffer = parent->buffer -
binder_alloc_get_user_buffer_offset(
&proc->alloc);
fd_buf_size = sizeof(u32) * fda->num_fds;
if (fda->num_fds >= SIZE_MAX / sizeof(u32)) {
pr_err("transaction release %d invalid number of fds (%lld)\n",
debug_id, (u64)fda->num_fds);
continue;
}
if (fd_buf_size > parent->length ||
fda->parent_offset > parent->length - fd_buf_size) {
/* No space for all file descriptors here. */
pr_err("transaction release %d not enough space for %lld fds in buffer\n",
debug_id, (u64)fda->num_fds);
continue;
}
fd_array = (u32 *)(parent_buffer + (uintptr_t)fda->parent_offset);
for (fd_index = 0; fd_index < fda->num_fds; fd_index++)
binder_deferred_fd_close(fd_array[fd_index]);
} break;
default:
pr_err("transaction release %d bad object type %x\n",
debug_id, hdr->type);
break;
}
}
}
static int binder_translate_binder(struct flat_binder_object *fp,
struct binder_transaction *t,
struct binder_thread *thread)
{
struct binder_node *node;
struct binder_proc *proc = thread->proc;
struct binder_proc *target_proc = t->to_proc;
struct binder_ref_data rdata;
int ret = 0;
node = binder_get_node(proc, fp->binder);
if (!node) {
node = binder_new_node(proc, fp);
if (!node)
return -ENOMEM;
}
if (fp->cookie != node->cookie) {
binder_user_error("%d:%d sending u%016llx node %d, cookie mismatch %016llx != %016llx\n",
proc->pid, thread->pid, (u64)fp->binder,
node->debug_id, (u64)fp->cookie,
(u64)node->cookie);
ret = -EINVAL;
goto done;
}
if (security_binder_transfer_binder(proc->tsk, target_proc->tsk)) {
ret = -EPERM;
goto done;
}
ret = binder_inc_ref_for_node(target_proc, node,
fp->hdr.type == BINDER_TYPE_BINDER,
&thread->todo, &rdata);
if (ret)
goto done;
if (fp->hdr.type == BINDER_TYPE_BINDER)
fp->hdr.type = BINDER_TYPE_HANDLE;
else
fp->hdr.type = BINDER_TYPE_WEAK_HANDLE;
fp->binder = 0;
fp->handle = rdata.desc;
fp->cookie = 0;
trace_binder_transaction_node_to_ref(t, node, &rdata);
binder_debug(BINDER_DEBUG_TRANSACTION,
" node %d u%016llx -> ref %d desc %d\n",
node->debug_id, (u64)node->ptr,
rdata.debug_id, rdata.desc);
done:
binder_put_node(node);
return ret;
}
static int binder_translate_handle(struct flat_binder_object *fp,
struct binder_transaction *t,
struct binder_thread *thread)
{
struct binder_proc *proc = thread->proc;
struct binder_proc *target_proc = t->to_proc;
struct binder_node *node;
struct binder_ref_data src_rdata;
int ret = 0;
node = binder_get_node_from_ref(proc, fp->handle,
fp->hdr.type == BINDER_TYPE_HANDLE, &src_rdata);
if (!node) {
binder_user_error("%d:%d got transaction with invalid handle, %d\n",
proc->pid, thread->pid, fp->handle);
return -EINVAL;
}
if (security_binder_transfer_binder(proc->tsk, target_proc->tsk)) {
ret = -EPERM;
goto done;
}
binder_node_lock(node);
if (node->proc == target_proc) {
if (fp->hdr.type == BINDER_TYPE_HANDLE)
fp->hdr.type = BINDER_TYPE_BINDER;
else
fp->hdr.type = BINDER_TYPE_WEAK_BINDER;
fp->binder = node->ptr;
fp->cookie = node->cookie;
if (node->proc)
binder_inner_proc_lock(node->proc);
else
__acquire(&node->proc->inner_lock);
binder_inc_node_nilocked(node,
fp->hdr.type == BINDER_TYPE_BINDER,
0, NULL);
if (node->proc)
binder_inner_proc_unlock(node->proc);
else
__release(&node->proc->inner_lock);
trace_binder_transaction_ref_to_node(t, node, &src_rdata);
binder_debug(BINDER_DEBUG_TRANSACTION,
" ref %d desc %d -> node %d u%016llx\n",
src_rdata.debug_id, src_rdata.desc, node->debug_id,
(u64)node->ptr);
binder_node_unlock(node);
} else {
struct binder_ref_data dest_rdata;
binder_node_unlock(node);
ret = binder_inc_ref_for_node(target_proc, node,
fp->hdr.type == BINDER_TYPE_HANDLE,
NULL, &dest_rdata);
if (ret)
goto done;
fp->binder = 0;
fp->handle = dest_rdata.desc;
fp->cookie = 0;
trace_binder_transaction_ref_to_ref(t, node, &src_rdata,
&dest_rdata);
binder_debug(BINDER_DEBUG_TRANSACTION,
" ref %d desc %d -> ref %d desc %d (node %d)\n",
src_rdata.debug_id, src_rdata.desc,
dest_rdata.debug_id, dest_rdata.desc,
node->debug_id);
}
done:
binder_put_node(node);
return ret;
}
static int binder_translate_fd(u32 *fdp,
struct binder_transaction *t,
struct binder_thread *thread,
struct binder_transaction *in_reply_to)
{
struct binder_proc *proc = thread->proc;
struct binder_proc *target_proc = t->to_proc;
struct binder_txn_fd_fixup *fixup;
struct file *file;
int ret = 0;
bool target_allows_fd;
int fd = *fdp;
if (in_reply_to)
target_allows_fd = !!(in_reply_to->flags & TF_ACCEPT_FDS);
else
target_allows_fd = t->buffer->target_node->accept_fds;
if (!target_allows_fd) {
binder_user_error("%d:%d got %s with fd, %d, but target does not allow fds\n",
proc->pid, thread->pid,
in_reply_to ? "reply" : "transaction",
fd);
ret = -EPERM;
goto err_fd_not_accepted;
}
file = fget(fd);
if (!file) {
binder_user_error("%d:%d got transaction with invalid fd, %d\n",
proc->pid, thread->pid, fd);
ret = -EBADF;
goto err_fget;
}
ret = security_binder_transfer_file(proc->tsk, target_proc->tsk, file);
if (ret < 0) {
ret = -EPERM;
goto err_security;
}
/*
* Add fixup record for this transaction. The allocation
* of the fd in the target needs to be done from a
* target thread.
*/
fixup = kzalloc(sizeof(*fixup), GFP_KERNEL);
if (!fixup) {
ret = -ENOMEM;
goto err_alloc;
}
fixup->file = file;
fixup->offset = (uintptr_t)fdp - (uintptr_t)t->buffer->data;
trace_binder_transaction_fd_send(t, fd, fixup->offset);
list_add_tail(&fixup->fixup_entry, &t->fd_fixups);
return ret;
err_alloc:
err_security:
fput(file);
err_fget:
err_fd_not_accepted:
return ret;
}
static int binder_translate_fd_array(struct binder_fd_array_object *fda,
struct binder_buffer_object *parent,
struct binder_transaction *t,
struct binder_thread *thread,
struct binder_transaction *in_reply_to)
{
binder_size_t fdi, fd_buf_size;
uintptr_t parent_buffer;
u32 *fd_array;
struct binder_proc *proc = thread->proc;
struct binder_proc *target_proc = t->to_proc;
fd_buf_size = sizeof(u32) * fda->num_fds;
if (fda->num_fds >= SIZE_MAX / sizeof(u32)) {
binder_user_error("%d:%d got transaction with invalid number of fds (%lld)\n",
proc->pid, thread->pid, (u64)fda->num_fds);
return -EINVAL;
}
if (fd_buf_size > parent->length ||
fda->parent_offset > parent->length - fd_buf_size) {
/* No space for all file descriptors here. */
binder_user_error("%d:%d not enough space to store %lld fds in buffer\n",
proc->pid, thread->pid, (u64)fda->num_fds);
return -EINVAL;
}
/*
* Since the parent was already fixed up, convert it
* back to the kernel address space to access it
*/
parent_buffer = parent->buffer -
binder_alloc_get_user_buffer_offset(&target_proc->alloc);
fd_array = (u32 *)(parent_buffer + (uintptr_t)fda->parent_offset);
if (!IS_ALIGNED((unsigned long)fd_array, sizeof(u32))) {
binder_user_error("%d:%d parent offset not aligned correctly.\n",
proc->pid, thread->pid);
return -EINVAL;
}
for (fdi = 0; fdi < fda->num_fds; fdi++) {
int ret = binder_translate_fd(&fd_array[fdi], t, thread,
in_reply_to);
if (ret < 0)
return ret;
}
return 0;
}
static int binder_fixup_parent(struct binder_transaction *t,
struct binder_thread *thread,
struct binder_buffer_object *bp,
binder_size_t *off_start,
binder_size_t num_valid,
struct binder_buffer_object *last_fixup_obj,
binder_size_t last_fixup_min_off)
{
struct binder_buffer_object *parent;
u8 *parent_buffer;
struct binder_buffer *b = t->buffer;
struct binder_proc *proc = thread->proc;
struct binder_proc *target_proc = t->to_proc;
if (!(bp->flags & BINDER_BUFFER_FLAG_HAS_PARENT))
return 0;
parent = binder_validate_ptr(b, bp->parent, off_start, num_valid);
if (!parent) {
binder_user_error("%d:%d got transaction with invalid parent offset or type\n",
proc->pid, thread->pid);
return -EINVAL;
}
if (!binder_validate_fixup(b, off_start,
parent, bp->parent_offset,
last_fixup_obj,
last_fixup_min_off)) {
binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n",
proc->pid, thread->pid);
return -EINVAL;
}
if (parent->length < sizeof(binder_uintptr_t) ||
bp->parent_offset > parent->length - sizeof(binder_uintptr_t)) {
/* No space for a pointer here! */
binder_user_error("%d:%d got transaction with invalid parent offset\n",
proc->pid, thread->pid);
return -EINVAL;
}
parent_buffer = (u8 *)((uintptr_t)parent->buffer -
binder_alloc_get_user_buffer_offset(
&target_proc->alloc));
*(binder_uintptr_t *)(parent_buffer + bp->parent_offset) = bp->buffer;
return 0;
}
/**
* binder_proc_transaction() - sends a transaction to a process and wakes it up
* @t: transaction to send
* @proc: process to send the transaction to
* @thread: thread in @proc to send the transaction to (may be NULL)
*
* This function queues a transaction to the specified process. It will try
* to find a thread in the target process to handle the transaction and
* wake it up. If no thread is found, the work is queued to the proc
* waitqueue.
*
* If the @thread parameter is not NULL, the transaction is always queued
* to the waitlist of that specific thread.
*
* Return: true if the transactions was successfully queued
* false if the target process or thread is dead
*/
static bool binder_proc_transaction(struct binder_transaction *t,
struct binder_proc *proc,
struct binder_thread *thread)
{
struct binder_node *node = t->buffer->target_node;
bool oneway = !!(t->flags & TF_ONE_WAY);
bool pending_async = false;
BUG_ON(!node);
binder_node_lock(node);
if (oneway) {
BUG_ON(thread);
if (node->has_async_transaction) {
pending_async = true;
} else {
node->has_async_transaction = true;
}
}
binder_inner_proc_lock(proc);
if (proc->is_dead || (thread && thread->is_dead)) {
binder_inner_proc_unlock(proc);
binder_node_unlock(node);
return false;
}
if (!thread && !pending_async)
thread = binder_select_thread_ilocked(proc);
if (thread)
binder_enqueue_thread_work_ilocked(thread, &t->work);
else if (!pending_async)
binder_enqueue_work_ilocked(&t->work, &proc->todo);
else
binder_enqueue_work_ilocked(&t->work, &node->async_todo);
if (!pending_async)
binder_wakeup_thread_ilocked(proc, thread, !oneway /* sync */);
binder_inner_proc_unlock(proc);
binder_node_unlock(node);
return true;
}
/**
* binder_get_node_refs_for_txn() - Get required refs on node for txn
* @node: struct binder_node for which to get refs
* @proc: returns @node->proc if valid
* @error: if no @proc then returns BR_DEAD_REPLY
*
* User-space normally keeps the node alive when creating a transaction
* since it has a reference to the target. The local strong ref keeps it
* alive if the sending process dies before the target process processes
* the transaction. If the source process is malicious or has a reference
* counting bug, relying on the local strong ref can fail.
*
* Since user-space can cause the local strong ref to go away, we also take
* a tmpref on the node to ensure it survives while we are constructing
* the transaction. We also need a tmpref on the proc while we are
* constructing the transaction, so we take that here as well.
*
* Return: The target_node with refs taken or NULL if no @node->proc is NULL.
* Also sets @proc if valid. If the @node->proc is NULL indicating that the
* target proc has died, @error is set to BR_DEAD_REPLY
*/
static struct binder_node *binder_get_node_refs_for_txn(
struct binder_node *node,
struct binder_proc **procp,
uint32_t *error)
{
struct binder_node *target_node = NULL;
binder_node_inner_lock(node);
if (node->proc) {
target_node = node;
binder_inc_node_nilocked(node, 1, 0, NULL);
binder_inc_node_tmpref_ilocked(node);
node->proc->tmp_ref++;
*procp = node->proc;
} else
*error = BR_DEAD_REPLY;
binder_node_inner_unlock(node);
return target_node;
}
static void binder_transaction(struct binder_proc *proc,
struct binder_thread *thread,
struct binder_transaction_data *tr, int reply,
binder_size_t extra_buffers_size)
{
int ret;
struct binder_transaction *t;
struct binder_work *w;
struct binder_work *tcomplete;
binder_size_t *offp, *off_end, *off_start;
binder_size_t off_min;
u8 *sg_bufp, *sg_buf_end;
struct binder_proc *target_proc = NULL;
struct binder_thread *target_thread = NULL;
struct binder_node *target_node = NULL;
struct binder_transaction *in_reply_to = NULL;
struct binder_transaction_log_entry *e;
uint32_t return_error = 0;
uint32_t return_error_param = 0;
uint32_t return_error_line = 0;
struct binder_buffer_object *last_fixup_obj = NULL;
binder_size_t last_fixup_min_off = 0;
struct binder_context *context = proc->context;
int t_debug_id = atomic_inc_return(&binder_last_id);
e = binder_transaction_log_add(&binder_transaction_log);
e->debug_id = t_debug_id;
e->call_type = reply ? 2 : !!(tr->flags & TF_ONE_WAY);
e->from_proc = proc->pid;
e->from_thread = thread->pid;
e->target_handle = tr->target.handle;
e->data_size = tr->data_size;
e->offsets_size = tr->offsets_size;
e->context_name = proc->context->name;
if (reply) {
binder_inner_proc_lock(proc);
in_reply_to = thread->transaction_stack;
if (in_reply_to == NULL) {
binder_inner_proc_unlock(proc);
binder_user_error("%d:%d got reply transaction with no transaction stack\n",
proc->pid, thread->pid);
return_error = BR_FAILED_REPLY;
return_error_param = -EPROTO;
return_error_line = __LINE__;
goto err_empty_call_stack;
}
if (in_reply_to->to_thread != thread) {
spin_lock(&in_reply_to->lock);
binder_user_error("%d:%d got reply transaction with bad transaction stack, transaction %d has target %d:%d\n",
proc->pid, thread->pid, in_reply_to->debug_id,
in_reply_to->to_proc ?
in_reply_to->to_proc->pid : 0,
in_reply_to->to_thread ?
in_reply_to->to_thread->pid : 0);
spin_unlock(&in_reply_to->lock);
binder_inner_proc_unlock(proc);
return_error = BR_FAILED_REPLY;
return_error_param = -EPROTO;
return_error_line = __LINE__;
in_reply_to = NULL;
goto err_bad_call_stack;
}
thread->transaction_stack = in_reply_to->to_parent;
binder_inner_proc_unlock(proc);
binder_set_nice(in_reply_to->saved_priority);
target_thread = binder_get_txn_from_and_acq_inner(in_reply_to);
if (target_thread == NULL) {
/* annotation for sparse */
__release(&target_thread->proc->inner_lock);
return_error = BR_DEAD_REPLY;
return_error_line = __LINE__;
goto err_dead_binder;
}
if (target_thread->transaction_stack != in_reply_to) {
binder_user_error("%d:%d got reply transaction with bad target transaction stack %d, expected %d\n",
proc->pid, thread->pid,
target_thread->transaction_stack ?
target_thread->transaction_stack->debug_id : 0,
in_reply_to->debug_id);
binder_inner_proc_unlock(target_thread->proc);
return_error = BR_FAILED_REPLY;
return_error_param = -EPROTO;
return_error_line = __LINE__;
in_reply_to = NULL;
target_thread = NULL;
goto err_dead_binder;
}
target_proc = target_thread->proc;
target_proc->tmp_ref++;
binder_inner_proc_unlock(target_thread->proc);
} else {
if (tr->target.handle) {
struct binder_ref *ref;
/*
* There must already be a strong ref
* on this node. If so, do a strong
* increment on the node to ensure it
* stays alive until the transaction is
* done.
*/
binder_proc_lock(proc);
ref = binder_get_ref_olocked(proc, tr->target.handle,
true);
if (ref) {
target_node = binder_get_node_refs_for_txn(
ref->node, &target_proc,
&return_error);
} else {
binder_user_error("%d:%d got transaction to invalid handle\n",
proc->pid, thread->pid);
return_error = BR_FAILED_REPLY;
}
binder_proc_unlock(proc);
} else {
mutex_lock(&context->context_mgr_node_lock);
target_node = context->binder_context_mgr_node;
if (target_node)
target_node = binder_get_node_refs_for_txn(
target_node, &target_proc,
&return_error);
else
return_error = BR_DEAD_REPLY;
mutex_unlock(&context->context_mgr_node_lock);
if (target_node && target_proc == proc) {
binder_user_error("%d:%d got transaction to context manager from process owning it\n",
proc->pid, thread->pid);
return_error = BR_FAILED_REPLY;
return_error_param = -EINVAL;
return_error_line = __LINE__;
goto err_invalid_target_handle;
}
}
if (!target_node) {
/*
* return_error is set above
*/
return_error_param = -EINVAL;
return_error_line = __LINE__;
goto err_dead_binder;
}
e->to_node = target_node->debug_id;
if (security_binder_transaction(proc->tsk,
target_proc->tsk) < 0) {
return_error = BR_FAILED_REPLY;
return_error_param = -EPERM;
return_error_line = __LINE__;
goto err_invalid_target_handle;
}
binder_inner_proc_lock(proc);
w = list_first_entry_or_null(&thread->todo,
struct binder_work, entry);
if (!(tr->flags & TF_ONE_WAY) && w &&
w->type == BINDER_WORK_TRANSACTION) {
/*
* Do not allow new outgoing transaction from a
* thread that has a transaction at the head of
* its todo list. Only need to check the head
* because binder_select_thread_ilocked picks a
* thread from proc->waiting_threads to enqueue
* the transaction, and nothing is queued to the
* todo list while the thread is on waiting_threads.
*/
binder_user_error("%d:%d new transaction not allowed when there is a transaction on thread todo\n",
proc->pid, thread->pid);
binder_inner_proc_unlock(proc);
return_error = BR_FAILED_REPLY;
return_error_param = -EPROTO;
return_error_line = __LINE__;
goto err_bad_todo_list;
}
if (!(tr->flags & TF_ONE_WAY) && thread->transaction_stack) {
struct binder_transaction *tmp;
tmp = thread->transaction_stack;
if (tmp->to_thread != thread) {
spin_lock(&tmp->lock);
binder_user_error("%d:%d got new transaction with bad transaction stack, transaction %d has target %d:%d\n",
proc->pid, thread->pid, tmp->debug_id,
tmp->to_proc ? tmp->to_proc->pid : 0,
tmp->to_thread ?
tmp->to_thread->pid : 0);
spin_unlock(&tmp->lock);
binder_inner_proc_unlock(proc);
return_error = BR_FAILED_REPLY;
return_error_param = -EPROTO;
return_error_line = __LINE__;
goto err_bad_call_stack;
}
while (tmp) {
struct binder_thread *from;
spin_lock(&tmp->lock);
from = tmp->from;
if (from && from->proc == target_proc) {
atomic_inc(&from->tmp_ref);
target_thread = from;
spin_unlock(&tmp->lock);
break;
}
spin_unlock(&tmp->lock);
tmp = tmp->from_parent;
}
}
binder_inner_proc_unlock(proc);
}
if (target_thread)
e->to_thread = target_thread->pid;
e->to_proc = target_proc->pid;
/* TODO: reuse incoming transaction for reply */
t = kzalloc(sizeof(*t), GFP_KERNEL);
if (t == NULL) {
return_error = BR_FAILED_REPLY;
return_error_param = -ENOMEM;
return_error_line = __LINE__;
goto err_alloc_t_failed;
}
INIT_LIST_HEAD(&t->fd_fixups);
binder_stats_created(BINDER_STAT_TRANSACTION);
spin_lock_init(&t->lock);
tcomplete = kzalloc(sizeof(*tcomplete), GFP_KERNEL);
if (tcomplete == NULL) {
return_error = BR_FAILED_REPLY;
return_error_param = -ENOMEM;
return_error_line = __LINE__;
goto err_alloc_tcomplete_failed;
}
binder_stats_created(BINDER_STAT_TRANSACTION_COMPLETE);
t->debug_id = t_debug_id;
if (reply)
binder_debug(BINDER_DEBUG_TRANSACTION,
"%d:%d BC_REPLY %d -> %d:%d, data %016llx-%016llx size %lld-%lld-%lld\n",
proc->pid, thread->pid, t->debug_id,
target_proc->pid, target_thread->pid,
(u64)tr->data.ptr.buffer,
(u64)tr->data.ptr.offsets,
(u64)tr->data_size, (u64)tr->offsets_size,
(u64)extra_buffers_size);
else
binder_debug(BINDER_DEBUG_TRANSACTION,
"%d:%d BC_TRANSACTION %d -> %d - node %d, data %016llx-%016llx size %lld-%lld-%lld\n",
proc->pid, thread->pid, t->debug_id,
target_proc->pid, target_node->debug_id,
(u64)tr->data.ptr.buffer,
(u64)tr->data.ptr.offsets,
(u64)tr->data_size, (u64)tr->offsets_size,
(u64)extra_buffers_size);
if (!reply && !(tr->flags & TF_ONE_WAY))
t->from = thread;
else
t->from = NULL;
t->sender_euid = task_euid(proc->tsk);
t->to_proc = target_proc;
t->to_thread = target_thread;
t->code = tr->code;
t->flags = tr->flags;
t->priority = task_nice(current);
trace_binder_transaction(reply, t, target_node);
t->buffer = binder_alloc_new_buf(&target_proc->alloc, tr->data_size,
tr->offsets_size, extra_buffers_size,
!reply && (t->flags & TF_ONE_WAY));
if (IS_ERR(t->buffer)) {
/*
* -ESRCH indicates VMA cleared. The target is dying.
*/
return_error_param = PTR_ERR(t->buffer);
return_error = return_error_param == -ESRCH ?
BR_DEAD_REPLY : BR_FAILED_REPLY;
return_error_line = __LINE__;
t->buffer = NULL;
goto err_binder_alloc_buf_failed;
}
t->buffer->debug_id = t->debug_id;
t->buffer->transaction = t;
t->buffer->target_node = target_node;
trace_binder_transaction_alloc_buf(t->buffer);
off_start = (binder_size_t *)(t->buffer->data +
ALIGN(tr->data_size, sizeof(void *)));
offp = off_start;
if (copy_from_user(t->buffer->data, (const void __user *)(uintptr_t)
tr->data.ptr.buffer, tr->data_size)) {
binder_user_error("%d:%d got transaction with invalid data ptr\n",
proc->pid, thread->pid);
return_error = BR_FAILED_REPLY;
return_error_param = -EFAULT;
return_error_line = __LINE__;
goto err_copy_data_failed;
}
if (copy_from_user(offp, (const void __user *)(uintptr_t)
tr->data.ptr.offsets, tr->offsets_size)) {
binder_user_error("%d:%d got transaction with invalid offsets ptr\n",
proc->pid, thread->pid);
return_error = BR_FAILED_REPLY;
return_error_param = -EFAULT;
return_error_line = __LINE__;
goto err_copy_data_failed;
}
if (!IS_ALIGNED(tr->offsets_size, sizeof(binder_size_t))) {
binder_user_error("%d:%d got transaction with invalid offsets size, %lld\n",
proc->pid, thread->pid, (u64)tr->offsets_size);
return_error = BR_FAILED_REPLY;
return_error_param = -EINVAL;
return_error_line = __LINE__;
goto err_bad_offset;
}
if (!IS_ALIGNED(extra_buffers_size, sizeof(u64))) {
binder_user_error("%d:%d got transaction with unaligned buffers size, %lld\n",
proc->pid, thread->pid,
(u64)extra_buffers_size);
return_error = BR_FAILED_REPLY;
return_error_param = -EINVAL;
return_error_line = __LINE__;
goto err_bad_offset;
}
off_end = (void *)off_start + tr->offsets_size;
sg_bufp = (u8 *)(PTR_ALIGN(off_end, sizeof(void *)));
sg_buf_end = sg_bufp + extra_buffers_size;
off_min = 0;
for (; offp < off_end; offp++) {
struct binder_object_header *hdr;
size_t object_size = binder_validate_object(t->buffer, *offp);
if (object_size == 0 || *offp < off_min) {
binder_user_error("%d:%d got transaction with invalid offset (%lld, min %lld max %lld) or object.\n",
proc->pid, thread->pid, (u64)*offp,
(u64)off_min,
(u64)t->buffer->data_size);
return_error = BR_FAILED_REPLY;
return_error_param = -EINVAL;
return_error_line = __LINE__;
goto err_bad_offset;
}
hdr = (struct binder_object_header *)(t->buffer->data + *offp);
off_min = *offp + object_size;
switch (hdr->type) {
case BINDER_TYPE_BINDER:
case BINDER_TYPE_WEAK_BINDER: {
struct flat_binder_object *fp;
fp = to_flat_binder_object(hdr);
ret = binder_translate_binder(fp, t, thread);
if (ret < 0) {
return_error = BR_FAILED_REPLY;
return_error_param = ret;
return_error_line = __LINE__;
goto err_translate_failed;
}
} break;
case BINDER_TYPE_HANDLE:
case BINDER_TYPE_WEAK_HANDLE: {
struct flat_binder_object *fp;
fp = to_flat_binder_object(hdr);
ret = binder_translate_handle(fp, t, thread);
if (ret < 0) {
return_error = BR_FAILED_REPLY;
return_error_param = ret;
return_error_line = __LINE__;
goto err_translate_failed;
}
} break;
case BINDER_TYPE_FD: {
struct binder_fd_object *fp = to_binder_fd_object(hdr);
int ret = binder_translate_fd(&fp->fd, t, thread,
in_reply_to);
if (ret < 0) {
return_error = BR_FAILED_REPLY;
return_error_param = ret;
return_error_line = __LINE__;
goto err_translate_failed;
}
fp->pad_binder = 0;
} break;
case BINDER_TYPE_FDA: {
struct binder_fd_array_object *fda =
to_binder_fd_array_object(hdr);
struct binder_buffer_object *parent =
binder_validate_ptr(t->buffer, fda->parent,
off_start,
offp - off_start);
if (!parent) {
binder_user_error("%d:%d got transaction with invalid parent offset or type\n",
proc->pid, thread->pid);
return_error = BR_FAILED_REPLY;
return_error_param = -EINVAL;
return_error_line = __LINE__;
goto err_bad_parent;
}
if (!binder_validate_fixup(t->buffer, off_start,
parent, fda->parent_offset,
last_fixup_obj,
last_fixup_min_off)) {
binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n",
proc->pid, thread->pid);
return_error = BR_FAILED_REPLY;
return_error_param = -EINVAL;
return_error_line = __LINE__;
goto err_bad_parent;
}
ret = binder_translate_fd_array(fda, parent, t, thread,
in_reply_to);
if (ret < 0) {
return_error = BR_FAILED_REPLY;
return_error_param = ret;
return_error_line = __LINE__;
goto err_translate_failed;
}
last_fixup_obj = parent;
last_fixup_min_off =
fda->parent_offset + sizeof(u32) * fda->num_fds;
} break;
case BINDER_TYPE_PTR: {
struct binder_buffer_object *bp =
to_binder_buffer_object(hdr);
size_t buf_left = sg_buf_end - sg_bufp;
if (bp->length > buf_left) {
binder_user_error("%d:%d got transaction with too large buffer\n",
proc->pid, thread->pid);
return_error = BR_FAILED_REPLY;
return_error_param = -EINVAL;
return_error_line = __LINE__;
goto err_bad_offset;
}
if (copy_from_user(sg_bufp,
(const void __user *)(uintptr_t)
bp->buffer, bp->length)) {
binder_user_error("%d:%d got transaction with invalid offsets ptr\n",
proc->pid, thread->pid);
return_error_param = -EFAULT;
return_error = BR_FAILED_REPLY;
return_error_line = __LINE__;
goto err_copy_data_failed;
}
/* Fixup buffer pointer to target proc address space */
bp->buffer = (uintptr_t)sg_bufp +
binder_alloc_get_user_buffer_offset(
&target_proc->alloc);
sg_bufp += ALIGN(bp->length, sizeof(u64));
ret = binder_fixup_parent(t, thread, bp, off_start,
offp - off_start,
last_fixup_obj,
last_fixup_min_off);
if (ret < 0) {
return_error = BR_FAILED_REPLY;
return_error_param = ret;
return_error_line = __LINE__;
goto err_translate_failed;
}
last_fixup_obj = bp;
last_fixup_min_off = 0;
} break;
default:
binder_user_error("%d:%d got transaction with invalid object type, %x\n",
proc->pid, thread->pid, hdr->type);
return_error = BR_FAILED_REPLY;
return_error_param = -EINVAL;
return_error_line = __LINE__;
goto err_bad_object_type;
}
}
tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE;
t->work.type = BINDER_WORK_TRANSACTION;
if (reply) {
binder_enqueue_thread_work(thread, tcomplete);
binder_inner_proc_lock(target_proc);
if (target_thread->is_dead) {
binder_inner_proc_unlock(target_proc);
goto err_dead_proc_or_thread;
}
BUG_ON(t->buffer->async_transaction != 0);
binder_pop_transaction_ilocked(target_thread, in_reply_to);
binder_enqueue_thread_work_ilocked(target_thread, &t->work);
binder_inner_proc_unlock(target_proc);
wake_up_interruptible_sync(&target_thread->wait);
binder_free_transaction(in_reply_to);
} else if (!(t->flags & TF_ONE_WAY)) {
BUG_ON(t->buffer->async_transaction != 0);
binder_inner_proc_lock(proc);
/*
* Defer the TRANSACTION_COMPLETE, so we don't return to
* userspace immediately; this allows the target process to
* immediately start processing this transaction, reducing
* latency. We will then return the TRANSACTION_COMPLETE when
* the target replies (or there is an error).
*/
binder_enqueue_deferred_thread_work_ilocked(thread, tcomplete);
t->need_reply = 1;
t->from_parent = thread->transaction_stack;
thread->transaction_stack = t;
binder_inner_proc_unlock(proc);
if (!binder_proc_transaction(t, target_proc, target_thread)) {
binder_inner_proc_lock(proc);
binder_pop_transaction_ilocked(thread, t);
binder_inner_proc_unlock(proc);
goto err_dead_proc_or_thread;
}
} else {
BUG_ON(target_node == NULL);
BUG_ON(t->buffer->async_transaction != 1);
binder_enqueue_thread_work(thread, tcomplete);
if (!binder_proc_transaction(t, target_proc, NULL))
goto err_dead_proc_or_thread;
}
if (target_thread)
binder_thread_dec_tmpref(target_thread);
binder_proc_dec_tmpref(target_proc);
if (target_node)
binder_dec_node_tmpref(target_node);
/*
* write barrier to synchronize with initialization
* of log entry
*/
smp_wmb();
WRITE_ONCE(e->debug_id_done, t_debug_id);
return;
err_dead_proc_or_thread:
return_error = BR_DEAD_REPLY;
return_error_line = __LINE__;
binder_dequeue_work(proc, tcomplete);
err_translate_failed:
err_bad_object_type:
err_bad_offset:
err_bad_parent:
err_copy_data_failed:
binder_free_txn_fixups(t);
trace_binder_transaction_failed_buffer_release(t->buffer);
binder_transaction_buffer_release(target_proc, t->buffer, offp);
if (target_node)
binder_dec_node_tmpref(target_node);
target_node = NULL;
t->buffer->transaction = NULL;
binder_alloc_free_buf(&target_proc->alloc, t->buffer);
err_binder_alloc_buf_failed:
kfree(tcomplete);
binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
err_alloc_tcomplete_failed:
kfree(t);
binder_stats_deleted(BINDER_STAT_TRANSACTION);
err_alloc_t_failed:
err_bad_todo_list:
err_bad_call_stack:
err_empty_call_stack:
err_dead_binder:
err_invalid_target_handle:
if (target_thread)
binder_thread_dec_tmpref(target_thread);
if (target_proc)
binder_proc_dec_tmpref(target_proc);
if (target_node) {
binder_dec_node(target_node, 1, 0);
binder_dec_node_tmpref(target_node);
}
binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
"%d:%d transaction failed %d/%d, size %lld-%lld line %d\n",
proc->pid, thread->pid, return_error, return_error_param,
(u64)tr->data_size, (u64)tr->offsets_size,
return_error_line);
{
struct binder_transaction_log_entry *fe;
e->return_error = return_error;
e->return_error_param = return_error_param;
e->return_error_line = return_error_line;
fe = binder_transaction_log_add(&binder_transaction_log_failed);
*fe = *e;
/*
* write barrier to synchronize with initialization
* of log entry
*/
smp_wmb();
WRITE_ONCE(e->debug_id_done, t_debug_id);
WRITE_ONCE(fe->debug_id_done, t_debug_id);
}
BUG_ON(thread->return_error.cmd != BR_OK);
if (in_reply_to) {
thread->return_error.cmd = BR_TRANSACTION_COMPLETE;
binder_enqueue_thread_work(thread, &thread->return_error.work);
binder_send_failed_reply(in_reply_to, return_error);
} else {
thread->return_error.cmd = return_error;
binder_enqueue_thread_work(thread, &thread->return_error.work);
}
}
/**
* binder_free_buf() - free the specified buffer
* @proc: binder proc that owns buffer
* @buffer: buffer to be freed
*
* If buffer for an async transaction, enqueue the next async
* transaction from the node.
*
* Cleanup buffer and free it.
*/
static void
binder_free_buf(struct binder_proc *proc, struct binder_buffer *buffer)
{
if (buffer->transaction) {
buffer->transaction->buffer = NULL;
buffer->transaction = NULL;
}
if (buffer->async_transaction && buffer->target_node) {
struct binder_node *buf_node;
struct binder_work *w;
buf_node = buffer->target_node;
binder_node_inner_lock(buf_node);
BUG_ON(!buf_node->has_async_transaction);
BUG_ON(buf_node->proc != proc);
w = binder_dequeue_work_head_ilocked(
&buf_node->async_todo);
if (!w) {
buf_node->has_async_transaction = false;
} else {
binder_enqueue_work_ilocked(
w, &proc->todo);
binder_wakeup_proc_ilocked(proc);
}
binder_node_inner_unlock(buf_node);
}
trace_binder_transaction_buffer_release(buffer);
binder_transaction_buffer_release(proc, buffer, NULL);
binder_alloc_free_buf(&proc->alloc, buffer);
}
static int binder_thread_write(struct binder_proc *proc,
struct binder_thread *thread,
binder_uintptr_t binder_buffer, size_t size,
binder_size_t *consumed)
{
uint32_t cmd;
struct binder_context *context = proc->context;
void __user *buffer = (void __user *)(uintptr_t)binder_buffer;
void __user *ptr = buffer + *consumed;
void __user *end = buffer + size;
while (ptr < end && thread->return_error.cmd == BR_OK) {
int ret;
if (get_user(cmd, (uint32_t __user *)ptr))
return -EFAULT;
ptr += sizeof(uint32_t);
trace_binder_command(cmd);
if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.bc)) {
atomic_inc(&binder_stats.bc[_IOC_NR(cmd)]);
atomic_inc(&proc->stats.bc[_IOC_NR(cmd)]);
atomic_inc(&thread->stats.bc[_IOC_NR(cmd)]);
}
switch (cmd) {
case BC_INCREFS:
case BC_ACQUIRE:
case BC_RELEASE:
case BC_DECREFS: {
uint32_t target;
const char *debug_string;
bool strong = cmd == BC_ACQUIRE || cmd == BC_RELEASE;
bool increment = cmd == BC_INCREFS || cmd == BC_ACQUIRE;
struct binder_ref_data rdata;
if (get_user(target, (uint32_t __user *)ptr))
return -EFAULT;
ptr += sizeof(uint32_t);
ret = -1;
if (increment && !target) {
struct binder_node *ctx_mgr_node;
mutex_lock(&context->context_mgr_node_lock);
ctx_mgr_node = context->binder_context_mgr_node;
if (ctx_mgr_node)
ret = binder_inc_ref_for_node(
proc, ctx_mgr_node,
strong, NULL, &rdata);
mutex_unlock(&context->context_mgr_node_lock);
}
if (ret)
ret = binder_update_ref_for_handle(
proc, target, increment, strong,
&rdata);
if (!ret && rdata.desc != target) {
binder_user_error("%d:%d tried to acquire reference to desc %d, got %d instead\n",
proc->pid, thread->pid,
target, rdata.desc);
}
switch (cmd) {
case BC_INCREFS:
debug_string = "IncRefs";
break;
case BC_ACQUIRE:
debug_string = "Acquire";
break;
case BC_RELEASE:
debug_string = "Release";
break;
case BC_DECREFS:
default:
debug_string = "DecRefs";
break;
}
if (ret) {
binder_user_error("%d:%d %s %d refcount change on invalid ref %d ret %d\n",
proc->pid, thread->pid, debug_string,
strong, target, ret);
break;
}
binder_debug(BINDER_DEBUG_USER_REFS,
"%d:%d %s ref %d desc %d s %d w %d\n",
proc->pid, thread->pid, debug_string,
rdata.debug_id, rdata.desc, rdata.strong,
rdata.weak);
break;
}
case BC_INCREFS_DONE:
case BC_ACQUIRE_DONE: {
binder_uintptr_t node_ptr;
binder_uintptr_t cookie;
struct binder_node *node;
bool free_node;
if (get_user(node_ptr, (binder_uintptr_t __user *)ptr))
return -EFAULT;
ptr += sizeof(binder_uintptr_t);
if (get_user(cookie, (binder_uintptr_t __user *)ptr))
return -EFAULT;
ptr += sizeof(binder_uintptr_t);
node = binder_get_node(proc, node_ptr);
if (node == NULL) {
binder_user_error("%d:%d %s u%016llx no match\n",
proc->pid, thread->pid,
cmd == BC_INCREFS_DONE ?
"BC_INCREFS_DONE" :
"BC_ACQUIRE_DONE",
(u64)node_ptr);
break;
}
if (cookie != node->cookie) {
binder_user_error("%d:%d %s u%016llx node %d cookie mismatch %016llx != %016llx\n",
proc->pid, thread->pid,
cmd == BC_INCREFS_DONE ?
"BC_INCREFS_DONE" : "BC_ACQUIRE_DONE",
(u64)node_ptr, node->debug_id,
(u64)cookie, (u64)node->cookie);
binder_put_node(node);
break;
}
binder_node_inner_lock(node);
if (cmd == BC_ACQUIRE_DONE) {
if (node->pending_strong_ref == 0) {
binder_user_error("%d:%d BC_ACQUIRE_DONE node %d has no pending acquire request\n",
proc->pid, thread->pid,
node->debug_id);
binder_node_inner_unlock(node);
binder_put_node(node);
break;
}
node->pending_strong_ref = 0;
} else {
if (node->pending_weak_ref == 0) {
binder_user_error("%d:%d BC_INCREFS_DONE node %d has no pending increfs request\n",
proc->pid, thread->pid,
node->debug_id);
binder_node_inner_unlock(node);
binder_put_node(node);
break;
}
node->pending_weak_ref = 0;
}
free_node = binder_dec_node_nilocked(node,
cmd == BC_ACQUIRE_DONE, 0);
WARN_ON(free_node);
binder_debug(BINDER_DEBUG_USER_REFS,
"%d:%d %s node %d ls %d lw %d tr %d\n",
proc->pid, thread->pid,
cmd == BC_INCREFS_DONE ? "BC_INCREFS_DONE" : "BC_ACQUIRE_DONE",
node->debug_id, node->local_strong_refs,
node->local_weak_refs, node->tmp_refs);
binder_node_inner_unlock(node);
binder_put_node(node);
break;
}
case BC_ATTEMPT_ACQUIRE:
pr_err("BC_ATTEMPT_ACQUIRE not supported\n");
return -EINVAL;
case BC_ACQUIRE_RESULT:
pr_err("BC_ACQUIRE_RESULT not supported\n");
return -EINVAL;
case BC_FREE_BUFFER: {
binder_uintptr_t data_ptr;
struct binder_buffer *buffer;
if (get_user(data_ptr, (binder_uintptr_t __user *)ptr))
return -EFAULT;
ptr += sizeof(binder_uintptr_t);
buffer = binder_alloc_prepare_to_free(&proc->alloc,
data_ptr);
if (IS_ERR_OR_NULL(buffer)) {
if (PTR_ERR(buffer) == -EPERM) {
binder_user_error(
"%d:%d BC_FREE_BUFFER u%016llx matched unreturned or currently freeing buffer\n",
proc->pid, thread->pid,
(u64)data_ptr);
} else {
binder_user_error(
"%d:%d BC_FREE_BUFFER u%016llx no match\n",
proc->pid, thread->pid,
(u64)data_ptr);
}
break;
}
binder_debug(BINDER_DEBUG_FREE_BUFFER,
"%d:%d BC_FREE_BUFFER u%016llx found buffer %d for %s transaction\n",
proc->pid, thread->pid, (u64)data_ptr,
buffer->debug_id,
buffer->transaction ? "active" : "finished");
binder_free_buf(proc, buffer);
break;
}
case BC_TRANSACTION_SG:
case BC_REPLY_SG: {
struct binder_transaction_data_sg tr;
if (copy_from_user(&tr, ptr, sizeof(tr)))
return -EFAULT;
ptr += sizeof(tr);
binder_transaction(proc, thread, &tr.transaction_data,
cmd == BC_REPLY_SG, tr.buffers_size);
break;
}
case BC_TRANSACTION:
case BC_REPLY: {
struct binder_transaction_data tr;
if (copy_from_user(&tr, ptr, sizeof(tr)))
return -EFAULT;
ptr += sizeof(tr);
binder_transaction(proc, thread, &tr,
cmd == BC_REPLY, 0);
break;
}
case BC_REGISTER_LOOPER:
binder_debug(BINDER_DEBUG_THREADS,
"%d:%d BC_REGISTER_LOOPER\n",
proc->pid, thread->pid);
binder_inner_proc_lock(proc);
if (thread->looper & BINDER_LOOPER_STATE_ENTERED) {
thread->looper |= BINDER_LOOPER_STATE_INVALID;
binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called after BC_ENTER_LOOPER\n",
proc->pid, thread->pid);
} else if (proc->requested_threads == 0) {
thread->looper |= BINDER_LOOPER_STATE_INVALID;
binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called without request\n",
proc->pid, thread->pid);
} else {
proc->requested_threads--;
proc->requested_threads_started++;
}
thread->looper |= BINDER_LOOPER_STATE_REGISTERED;
binder_inner_proc_unlock(proc);
break;
case BC_ENTER_LOOPER:
binder_debug(BINDER_DEBUG_THREADS,
"%d:%d BC_ENTER_LOOPER\n",
proc->pid, thread->pid);
if (thread->looper & BINDER_LOOPER_STATE_REGISTERED) {
thread->looper |= BINDER_LOOPER_STATE_INVALID;
binder_user_error("%d:%d ERROR: BC_ENTER_LOOPER called after BC_REGISTER_LOOPER\n",
proc->pid, thread->pid);
}
thread->looper |= BINDER_LOOPER_STATE_ENTERED;
break;
case BC_EXIT_LOOPER:
binder_debug(BINDER_DEBUG_THREADS,
"%d:%d BC_EXIT_LOOPER\n",
proc->pid, thread->pid);
thread->looper |= BINDER_LOOPER_STATE_EXITED;
break;
case BC_REQUEST_DEATH_NOTIFICATION:
case BC_CLEAR_DEATH_NOTIFICATION: {
uint32_t target;
binder_uintptr_t cookie;
struct binder_ref *ref;
struct binder_ref_death *death = NULL;
if (get_user(target, (uint32_t __user *)ptr))
return -EFAULT;
ptr += sizeof(uint32_t);
if (get_user(cookie, (binder_uintptr_t __user *)ptr))
return -EFAULT;
ptr += sizeof(binder_uintptr_t);
if (cmd == BC_REQUEST_DEATH_NOTIFICATION) {
/*
* Allocate memory for death notification
* before taking lock
*/
death = kzalloc(sizeof(*death), GFP_KERNEL);
if (death == NULL) {
WARN_ON(thread->return_error.cmd !=
BR_OK);
thread->return_error.cmd = BR_ERROR;
binder_enqueue_thread_work(
thread,
&thread->return_error.work);
binder_debug(
BINDER_DEBUG_FAILED_TRANSACTION,
"%d:%d BC_REQUEST_DEATH_NOTIFICATION failed\n",
proc->pid, thread->pid);
break;
}
}
binder_proc_lock(proc);
ref = binder_get_ref_olocked(proc, target, false);
if (ref == NULL) {
binder_user_error("%d:%d %s invalid ref %d\n",
proc->pid, thread->pid,
cmd == BC_REQUEST_DEATH_NOTIFICATION ?
"BC_REQUEST_DEATH_NOTIFICATION" :
"BC_CLEAR_DEATH_NOTIFICATION",
target);
binder_proc_unlock(proc);
kfree(death);
break;
}
binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION,
"%d:%d %s %016llx ref %d desc %d s %d w %d for node %d\n",
proc->pid, thread->pid,
cmd == BC_REQUEST_DEATH_NOTIFICATION ?
"BC_REQUEST_DEATH_NOTIFICATION" :
"BC_CLEAR_DEATH_NOTIFICATION",
(u64)cookie, ref->data.debug_id,
ref->data.desc, ref->data.strong,
ref->data.weak, ref->node->debug_id);
binder_node_lock(ref->node);
if (cmd == BC_REQUEST_DEATH_NOTIFICATION) {
if (ref->death) {
binder_user_error("%d:%d BC_REQUEST_DEATH_NOTIFICATION death notification already set\n",
proc->pid, thread->pid);
binder_node_unlock(ref->node);
binder_proc_unlock(proc);
kfree(death);
break;
}
binder_stats_created(BINDER_STAT_DEATH);
INIT_LIST_HEAD(&death->work.entry);
death->cookie = cookie;
ref->death = death;
if (ref->node->proc == NULL) {
ref->death->work.type = BINDER_WORK_DEAD_BINDER;
binder_inner_proc_lock(proc);
binder_enqueue_work_ilocked(
&ref->death->work, &proc->todo);
binder_wakeup_proc_ilocked(proc);
binder_inner_proc_unlock(proc);
}
} else {
if (ref->death == NULL) {
binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification not active\n",
proc->pid, thread->pid);
binder_node_unlock(ref->node);
binder_proc_unlock(proc);
break;
}
death = ref->death;
if (death->cookie != cookie) {
binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification cookie mismatch %016llx != %016llx\n",
proc->pid, thread->pid,
(u64)death->cookie,
(u64)cookie);
binder_node_unlock(ref->node);
binder_proc_unlock(proc);
break;
}
ref->death = NULL;
binder_inner_proc_lock(proc);
if (list_empty(&death->work.entry)) {
death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION;
if (thread->looper &
(BINDER_LOOPER_STATE_REGISTERED |
BINDER_LOOPER_STATE_ENTERED))
binder_enqueue_thread_work_ilocked(
thread,
&death->work);
else {
binder_enqueue_work_ilocked(
&death->work,
&proc->todo);
binder_wakeup_proc_ilocked(
proc);
}
} else {
BUG_ON(death->work.type != BINDER_WORK_DEAD_BINDER);
death->work.type = BINDER_WORK_DEAD_BINDER_AND_CLEAR;
}
binder_inner_proc_unlock(proc);
}
binder_node_unlock(ref->node);
binder_proc_unlock(proc);
} break;
case BC_DEAD_BINDER_DONE: {
struct binder_work *w;
binder_uintptr_t cookie;
struct binder_ref_death *death = NULL;
if (get_user(cookie, (binder_uintptr_t __user *)ptr))
return -EFAULT;
ptr += sizeof(cookie);
binder_inner_proc_lock(proc);
list_for_each_entry(w, &proc->delivered_death,
entry) {
struct binder_ref_death *tmp_death =
container_of(w,
struct binder_ref_death,
work);
if (tmp_death->cookie == cookie) {
death = tmp_death;
break;
}
}
binder_debug(BINDER_DEBUG_DEAD_BINDER,
"%d:%d BC_DEAD_BINDER_DONE %016llx found %pK\n",
proc->pid, thread->pid, (u64)cookie,
death);
if (death == NULL) {
binder_user_error("%d:%d BC_DEAD_BINDER_DONE %016llx not found\n",
proc->pid, thread->pid, (u64)cookie);
binder_inner_proc_unlock(proc);
break;
}
binder_dequeue_work_ilocked(&death->work);
if (death->work.type == BINDER_WORK_DEAD_BINDER_AND_CLEAR) {
death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION;
if (thread->looper &
(BINDER_LOOPER_STATE_REGISTERED |
BINDER_LOOPER_STATE_ENTERED))
binder_enqueue_thread_work_ilocked(
thread, &death->work);
else {
binder_enqueue_work_ilocked(
&death->work,
&proc->todo);
binder_wakeup_proc_ilocked(proc);
}
}
binder_inner_proc_unlock(proc);
} break;
default:
pr_err("%d:%d unknown command %d\n",
proc->pid, thread->pid, cmd);
return -EINVAL;
}
*consumed = ptr - buffer;
}
return 0;
}
static void binder_stat_br(struct binder_proc *proc,
struct binder_thread *thread, uint32_t cmd)
{
trace_binder_return(cmd);
if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.br)) {
atomic_inc(&binder_stats.br[_IOC_NR(cmd)]);
atomic_inc(&proc->stats.br[_IOC_NR(cmd)]);
atomic_inc(&thread->stats.br[_IOC_NR(cmd)]);
}
}
static int binder_put_node_cmd(struct binder_proc *proc,
struct binder_thread *thread,
void __user **ptrp,
binder_uintptr_t node_ptr,
binder_uintptr_t node_cookie,
int node_debug_id,
uint32_t cmd, const char *cmd_name)
{
void __user *ptr = *ptrp;
if (put_user(cmd, (uint32_t __user *)ptr))
return -EFAULT;
ptr += sizeof(uint32_t);
if (put_user(node_ptr, (binder_uintptr_t __user *)ptr))
return -EFAULT;
ptr += sizeof(binder_uintptr_t);
if (put_user(node_cookie, (binder_uintptr_t __user *)ptr))
return -EFAULT;
ptr += sizeof(binder_uintptr_t);
binder_stat_br(proc, thread, cmd);
binder_debug(BINDER_DEBUG_USER_REFS, "%d:%d %s %d u%016llx c%016llx\n",
proc->pid, thread->pid, cmd_name, node_debug_id,
(u64)node_ptr, (u64)node_cookie);
*ptrp = ptr;
return 0;
}
static int binder_wait_for_work(struct binder_thread *thread,
bool do_proc_work)
{
DEFINE_WAIT(wait);
struct binder_proc *proc = thread->proc;
int ret = 0;
freezer_do_not_count();
binder_inner_proc_lock(proc);
for (;;) {
prepare_to_wait(&thread->wait, &wait, TASK_INTERRUPTIBLE);
if (binder_has_work_ilocked(thread, do_proc_work))
break;
if (do_proc_work)
list_add(&thread->waiting_thread_node,
&proc->waiting_threads);
binder_inner_proc_unlock(proc);
schedule();
binder_inner_proc_lock(proc);
list_del_init(&thread->waiting_thread_node);
if (signal_pending(current)) {
ret = -ERESTARTSYS;
break;
}
}
finish_wait(&thread->wait, &wait);
binder_inner_proc_unlock(proc);
freezer_count();
return ret;
}
/**
* binder_apply_fd_fixups() - finish fd translation
* @t: binder transaction with list of fd fixups
*
* Now that we are in the context of the transaction target
* process, we can allocate and install fds. Process the
* list of fds to translate and fixup the buffer with the
* new fds.
*
* If we fail to allocate an fd, then free the resources by
* fput'ing files that have not been processed and ksys_close'ing
* any fds that have already been allocated.
*/
static int binder_apply_fd_fixups(struct binder_transaction *t)
{
struct binder_txn_fd_fixup *fixup, *tmp;
int ret = 0;
list_for_each_entry(fixup, &t->fd_fixups, fixup_entry) {
int fd = get_unused_fd_flags(O_CLOEXEC);
u32 *fdp;
if (fd < 0) {
binder_debug(BINDER_DEBUG_TRANSACTION,
"failed fd fixup txn %d fd %d\n",
t->debug_id, fd);
ret = -ENOMEM;
break;
}
binder_debug(BINDER_DEBUG_TRANSACTION,
"fd fixup txn %d fd %d\n",
t->debug_id, fd);
trace_binder_transaction_fd_recv(t, fd, fixup->offset);
fd_install(fd, fixup->file);
fixup->file = NULL;
fdp = (u32 *)(t->buffer->data + fixup->offset);
/*
* This store can cause problems for CPUs with a
* VIVT cache (eg ARMv5) since the cache cannot
* detect virtual aliases to the same physical cacheline.
* To support VIVT, this address and the user-space VA
* would both need to be flushed. Since this kernel
* VA is not constructed via page_to_virt(), we can't
* use flush_dcache_page() on it, so we'd have to use
* an internal function. If devices with VIVT ever
* need to run Android, we'll either need to go back
* to patching the translated fd from the sender side
* (using the non-standard kernel functions), or rework
* how the kernel uses the buffer to use page_to_virt()
* addresses instead of allocating in our own vm area.
*
* For now, we disable compilation if CONFIG_CPU_CACHE_VIVT.
*/
*fdp = fd;
}
list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
if (fixup->file) {
fput(fixup->file);
} else if (ret) {
u32 *fdp = (u32 *)(t->buffer->data + fixup->offset);
binder_deferred_fd_close(*fdp);
}
list_del(&fixup->fixup_entry);
kfree(fixup);
}
return ret;
}
static int binder_thread_read(struct binder_proc *proc,
struct binder_thread *thread,
binder_uintptr_t binder_buffer, size_t size,
binder_size_t *consumed, int non_block)
{
void __user *buffer = (void __user *)(uintptr_t)binder_buffer;
void __user *ptr = buffer + *consumed;
void __user *end = buffer + size;
int ret = 0;
int wait_for_proc_work;
if (*consumed == 0) {
if (put_user(BR_NOOP, (uint32_t __user *)ptr))
return -EFAULT;
ptr += sizeof(uint32_t);
}
retry:
binder_inner_proc_lock(proc);
wait_for_proc_work = binder_available_for_proc_work_ilocked(thread);
binder_inner_proc_unlock(proc);
thread->looper |= BINDER_LOOPER_STATE_WAITING;
trace_binder_wait_for_work(wait_for_proc_work,
!!thread->transaction_stack,
!binder_worklist_empty(proc, &thread->todo));
if (wait_for_proc_work) {
if (!(thread->looper & (BINDER_LOOPER_STATE_REGISTERED |
BINDER_LOOPER_STATE_ENTERED))) {
binder_user_error("%d:%d ERROR: Thread waiting for process work before calling BC_REGISTER_LOOPER or BC_ENTER_LOOPER (state %x)\n",
proc->pid, thread->pid, thread->looper);
wait_event_interruptible(binder_user_error_wait,
binder_stop_on_user_error < 2);
}
binder_set_nice(proc->default_priority);
}
if (non_block) {
if (!binder_has_work(thread, wait_for_proc_work))
ret = -EAGAIN;
} else {
ret = binder_wait_for_work(thread, wait_for_proc_work);
}
thread->looper &= ~BINDER_LOOPER_STATE_WAITING;
if (ret)
return ret;
while (1) {
uint32_t cmd;
struct binder_transaction_data tr;
struct binder_work *w = NULL;
struct list_head *list = NULL;
struct binder_transaction *t = NULL;
struct binder_thread *t_from;
binder_inner_proc_lock(proc);
if (!binder_worklist_empty_ilocked(&thread->todo))
list = &thread->todo;
else if (!binder_worklist_empty_ilocked(&proc->todo) &&
wait_for_proc_work)
list = &proc->todo;
else {
binder_inner_proc_unlock(proc);
/* no data added */
if (ptr - buffer == 4 && !thread->looper_need_return)
goto retry;
break;
}
if (end - ptr < sizeof(tr) + 4) {
binder_inner_proc_unlock(proc);
break;
}
w = binder_dequeue_work_head_ilocked(list);
if (binder_worklist_empty_ilocked(&thread->todo))
thread->process_todo = false;
switch (w->type) {
case BINDER_WORK_TRANSACTION: {
binder_inner_proc_unlock(proc);
t = container_of(w, struct binder_transaction, work);
} break;
case BINDER_WORK_RETURN_ERROR: {
struct binder_error *e = container_of(
w, struct binder_error, work);
WARN_ON(e->cmd == BR_OK);
binder_inner_proc_unlock(proc);
if (put_user(e->cmd, (uint32_t __user *)ptr))
return -EFAULT;
cmd = e->cmd;
e->cmd = BR_OK;
ptr += sizeof(uint32_t);
binder_stat_br(proc, thread, cmd);
} break;
case BINDER_WORK_TRANSACTION_COMPLETE: {
binder_inner_proc_unlock(proc);
cmd = BR_TRANSACTION_COMPLETE;
if (put_user(cmd, (uint32_t __user *)ptr))
return -EFAULT;
ptr += sizeof(uint32_t);
binder_stat_br(proc, thread, cmd);
binder_debug(BINDER_DEBUG_TRANSACTION_COMPLETE,
"%d:%d BR_TRANSACTION_COMPLETE\n",
proc->pid, thread->pid);
kfree(w);
binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
} break;
case BINDER_WORK_NODE: {
struct binder_node *node = container_of(w, struct binder_node, work);
int strong, weak;
binder_uintptr_t node_ptr = node->ptr;
binder_uintptr_t node_cookie = node->cookie;
int node_debug_id = node->debug_id;
int has_weak_ref;
int has_strong_ref;
void __user *orig_ptr = ptr;
BUG_ON(proc != node->proc);
strong = node->internal_strong_refs ||
node->local_strong_refs;
weak = !hlist_empty(&node->refs) ||
node->local_weak_refs ||
node->tmp_refs || strong;
has_strong_ref = node->has_strong_ref;
has_weak_ref = node->has_weak_ref;
if (weak && !has_weak_ref) {
node->has_weak_ref = 1;
node->pending_weak_ref = 1;
node->local_weak_refs++;
}
if (strong && !has_strong_ref) {
node->has_strong_ref = 1;
node->pending_strong_ref = 1;
node->local_strong_refs++;
}
if (!strong && has_strong_ref)
node->has_strong_ref = 0;
if (!weak && has_weak_ref)
node->has_weak_ref = 0;
if (!weak && !strong) {
binder_debug(BINDER_DEBUG_INTERNAL_REFS,
"%d:%d node %d u%016llx c%016llx deleted\n",
proc->pid, thread->pid,
node_debug_id,
(u64)node_ptr,
(u64)node_cookie);
rb_erase(&node->rb_node, &proc->nodes);
binder_inner_proc_unlock(proc);
binder_node_lock(node);
/*
* Acquire the node lock before freeing the
* node to serialize with other threads that
* may have been holding the node lock while
* decrementing this node (avoids race where
* this thread frees while the other thread
* is unlocking the node after the final
* decrement)
*/
binder_node_unlock(node);
binder_free_node(node);
} else
binder_inner_proc_unlock(proc);
if (weak && !has_weak_ref)
ret = binder_put_node_cmd(
proc, thread, &ptr, node_ptr,
node_cookie, node_debug_id,
BR_INCREFS, "BR_INCREFS");
if (!ret && strong && !has_strong_ref)
ret = binder_put_node_cmd(
proc, thread, &ptr, node_ptr,
node_cookie, node_debug_id,
BR_ACQUIRE, "BR_ACQUIRE");
if (!ret && !strong && has_strong_ref)
ret = binder_put_node_cmd(
proc, thread, &ptr, node_ptr,
node_cookie, node_debug_id,
BR_RELEASE, "BR_RELEASE");
if (!ret && !weak && has_weak_ref)
ret = binder_put_node_cmd(
proc, thread, &ptr, node_ptr,
node_cookie, node_debug_id,
BR_DECREFS, "BR_DECREFS");
if (orig_ptr == ptr)
binder_debug(BINDER_DEBUG_INTERNAL_REFS,
"%d:%d node %d u%016llx c%016llx state unchanged\n",
proc->pid, thread->pid,
node_debug_id,
(u64)node_ptr,
(u64)node_cookie);
if (ret)
return ret;
} break;
case BINDER_WORK_DEAD_BINDER:
case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: {
struct binder_ref_death *death;
uint32_t cmd;
binder_uintptr_t cookie;
death = container_of(w, struct binder_ref_death, work);
if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION)
cmd = BR_CLEAR_DEATH_NOTIFICATION_DONE;
else
cmd = BR_DEAD_BINDER;
cookie = death->cookie;
binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION,
"%d:%d %s %016llx\n",
proc->pid, thread->pid,
cmd == BR_DEAD_BINDER ?
"BR_DEAD_BINDER" :
"BR_CLEAR_DEATH_NOTIFICATION_DONE",
(u64)cookie);
if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION) {
binder_inner_proc_unlock(proc);
kfree(death);
binder_stats_deleted(BINDER_STAT_DEATH);
} else {
binder_enqueue_work_ilocked(
w, &proc->delivered_death);
binder_inner_proc_unlock(proc);
}
if (put_user(cmd, (uint32_t __user *)ptr))
return -EFAULT;
ptr += sizeof(uint32_t);
if (put_user(cookie,
(binder_uintptr_t __user *)ptr))
return -EFAULT;
ptr += sizeof(binder_uintptr_t);
binder_stat_br(proc, thread, cmd);
if (cmd == BR_DEAD_BINDER)
goto done; /* DEAD_BINDER notifications can cause transactions */
} break;
default:
binder_inner_proc_unlock(proc);
pr_err("%d:%d: bad work type %d\n",
proc->pid, thread->pid, w->type);
break;
}
if (!t)
continue;
BUG_ON(t->buffer == NULL);
if (t->buffer->target_node) {
struct binder_node *target_node = t->buffer->target_node;
tr.target.ptr = target_node->ptr;
tr.cookie = target_node->cookie;
t->saved_priority = task_nice(current);
if (t->priority < target_node->min_priority &&
!(t->flags & TF_ONE_WAY))
binder_set_nice(t->priority);
else if (!(t->flags & TF_ONE_WAY) ||
t->saved_priority > target_node->min_priority)
binder_set_nice(target_node->min_priority);
cmd = BR_TRANSACTION;
} else {
tr.target.ptr = 0;
tr.cookie = 0;
cmd = BR_REPLY;
}
tr.code = t->code;
tr.flags = t->flags;
tr.sender_euid = from_kuid(current_user_ns(), t->sender_euid);
t_from = binder_get_txn_from(t);
if (t_from) {
struct task_struct *sender = t_from->proc->tsk;
tr.sender_pid = task_tgid_nr_ns(sender,
task_active_pid_ns(current));
} else {
tr.sender_pid = 0;
}
ret = binder_apply_fd_fixups(t);
if (ret) {
struct binder_buffer *buffer = t->buffer;
bool oneway = !!(t->flags & TF_ONE_WAY);
int tid = t->debug_id;
if (t_from)
binder_thread_dec_tmpref(t_from);
buffer->transaction = NULL;
binder_cleanup_transaction(t, "fd fixups failed",
BR_FAILED_REPLY);
binder_free_buf(proc, buffer);
binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
"%d:%d %stransaction %d fd fixups failed %d/%d, line %d\n",
proc->pid, thread->pid,
oneway ? "async " :
(cmd == BR_REPLY ? "reply " : ""),
tid, BR_FAILED_REPLY, ret, __LINE__);
if (cmd == BR_REPLY) {
cmd = BR_FAILED_REPLY;
if (put_user(cmd, (uint32_t __user *)ptr))
return -EFAULT;
ptr += sizeof(uint32_t);
binder_stat_br(proc, thread, cmd);
break;
}
continue;
}
tr.data_size = t->buffer->data_size;
tr.offsets_size = t->buffer->offsets_size;
tr.data.ptr.buffer = (binder_uintptr_t)
((uintptr_t)t->buffer->data +
binder_alloc_get_user_buffer_offset(&proc->alloc));
tr.data.ptr.offsets = tr.data.ptr.buffer +
ALIGN(t->buffer->data_size,
sizeof(void *));
if (put_user(cmd, (uint32_t __user *)ptr)) {
if (t_from)
binder_thread_dec_tmpref(t_from);
binder_cleanup_transaction(t, "put_user failed",
BR_FAILED_REPLY);
return -EFAULT;
}
ptr += sizeof(uint32_t);
if (copy_to_user(ptr, &tr, sizeof(tr))) {
if (t_from)
binder_thread_dec_tmpref(t_from);
binder_cleanup_transaction(t, "copy_to_user failed",
BR_FAILED_REPLY);
return -EFAULT;
}
ptr += sizeof(tr);
trace_binder_transaction_received(t);
binder_stat_br(proc, thread, cmd);
binder_debug(BINDER_DEBUG_TRANSACTION,
"%d:%d %s %d %d:%d, cmd %d size %zd-%zd ptr %016llx-%016llx\n",
proc->pid, thread->pid,
(cmd == BR_TRANSACTION) ? "BR_TRANSACTION" :
"BR_REPLY",
t->debug_id, t_from ? t_from->proc->pid : 0,
t_from ? t_from->pid : 0, cmd,
t->buffer->data_size, t->buffer->offsets_size,
(u64)tr.data.ptr.buffer, (u64)tr.data.ptr.offsets);
if (t_from)
binder_thread_dec_tmpref(t_from);
t->buffer->allow_user_free = 1;
if (cmd == BR_TRANSACTION && !(t->flags & TF_ONE_WAY)) {
binder_inner_proc_lock(thread->proc);
t->to_parent = thread->transaction_stack;
t->to_thread = thread;
thread->transaction_stack = t;
binder_inner_proc_unlock(thread->proc);
} else {
binder_free_transaction(t);
}
break;
}
done:
*consumed = ptr - buffer;
binder_inner_proc_lock(proc);
if (proc->requested_threads == 0 &&
list_empty(&thread->proc->waiting_threads) &&
proc->requested_threads_started < proc->max_threads &&
(thread->looper & (BINDER_LOOPER_STATE_REGISTERED |
BINDER_LOOPER_STATE_ENTERED)) /* the user-space code fails to */
/*spawn a new thread if we leave this out */) {
proc->requested_threads++;
binder_inner_proc_unlock(proc);
binder_debug(BINDER_DEBUG_THREADS,
"%d:%d BR_SPAWN_LOOPER\n",
proc->pid, thread->pid);
if (put_user(BR_SPAWN_LOOPER, (uint32_t __user *)buffer))
return -EFAULT;
binder_stat_br(proc, thread, BR_SPAWN_LOOPER);
} else
binder_inner_proc_unlock(proc);
return 0;
}
static void binder_release_work(struct binder_proc *proc,
struct list_head *list)
{
struct binder_work *w;
while (1) {
w = binder_dequeue_work_head(proc, list);
if (!w)
return;
switch (w->type) {
case BINDER_WORK_TRANSACTION: {
struct binder_transaction *t;
t = container_of(w, struct binder_transaction, work);
binder_cleanup_transaction(t, "process died.",
BR_DEAD_REPLY);
} break;
case BINDER_WORK_RETURN_ERROR: {
struct binder_error *e = container_of(
w, struct binder_error, work);
binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
"undelivered TRANSACTION_ERROR: %u\n",
e->cmd);
} break;
case BINDER_WORK_TRANSACTION_COMPLETE: {
binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
"undelivered TRANSACTION_COMPLETE\n");
kfree(w);
binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
} break;
case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: {
struct binder_ref_death *death;
death = container_of(w, struct binder_ref_death, work);
binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
"undelivered death notification, %016llx\n",
(u64)death->cookie);
kfree(death);
binder_stats_deleted(BINDER_STAT_DEATH);
} break;
default:
pr_err("unexpected work type, %d, not freed\n",
w->type);
break;
}
}
}
static struct binder_thread *binder_get_thread_ilocked(
struct binder_proc *proc, struct binder_thread *new_thread)
{
struct binder_thread *thread = NULL;
struct rb_node *parent = NULL;
struct rb_node **p = &proc->threads.rb_node;
while (*p) {
parent = *p;
thread = rb_entry(parent, struct binder_thread, rb_node);
if (current->pid < thread->pid)
p = &(*p)->rb_left;
else if (current->pid > thread->pid)
p = &(*p)->rb_right;
else
return thread;
}
if (!new_thread)
return NULL;
thread = new_thread;
binder_stats_created(BINDER_STAT_THREAD);
thread->proc = proc;
thread->pid = current->pid;
atomic_set(&thread->tmp_ref, 0);
init_waitqueue_head(&thread->wait);
INIT_LIST_HEAD(&thread->todo);
rb_link_node(&thread->rb_node, parent, p);
rb_insert_color(&thread->rb_node, &proc->threads);
thread->looper_need_return = true;
thread->return_error.work.type = BINDER_WORK_RETURN_ERROR;
thread->return_error.cmd = BR_OK;
thread->reply_error.work.type = BINDER_WORK_RETURN_ERROR;
thread->reply_error.cmd = BR_OK;
INIT_LIST_HEAD(&new_thread->waiting_thread_node);
return thread;
}
static struct binder_thread *binder_get_thread(struct binder_proc *proc)
{
struct binder_thread *thread;
struct binder_thread *new_thread;
binder_inner_proc_lock(proc);
thread = binder_get_thread_ilocked(proc, NULL);
binder_inner_proc_unlock(proc);
if (!thread) {
new_thread = kzalloc(sizeof(*thread), GFP_KERNEL);
if (new_thread == NULL)
return NULL;
binder_inner_proc_lock(proc);
thread = binder_get_thread_ilocked(proc, new_thread);
binder_inner_proc_unlock(proc);
if (thread != new_thread)
kfree(new_thread);
}
return thread;
}
static void binder_free_proc(struct binder_proc *proc)
{
BUG_ON(!list_empty(&proc->todo));
BUG_ON(!list_empty(&proc->delivered_death));
binder_alloc_deferred_release(&proc->alloc);
put_task_struct(proc->tsk);
binder_stats_deleted(BINDER_STAT_PROC);
kfree(proc);
}
static void binder_free_thread(struct binder_thread *thread)
{
BUG_ON(!list_empty(&thread->todo));
binder_stats_deleted(BINDER_STAT_THREAD);
binder_proc_dec_tmpref(thread->proc);
kfree(thread);
}
static int binder_thread_release(struct binder_proc *proc,
struct binder_thread *thread)
{
struct binder_transaction *t;
struct binder_transaction *send_reply = NULL;
int active_transactions = 0;
struct binder_transaction *last_t = NULL;
binder_inner_proc_lock(thread->proc);
/*
* take a ref on the proc so it survives
* after we remove this thread from proc->threads.
* The corresponding dec is when we actually
* free the thread in binder_free_thread()
*/
proc->tmp_ref++;
/*
* take a ref on this thread to ensure it
* survives while we are releasing it
*/
atomic_inc(&thread->tmp_ref);
rb_erase(&thread->rb_node, &proc->threads);
t = thread->transaction_stack;
if (t) {
spin_lock(&t->lock);
if (t->to_thread == thread)
send_reply = t;
} else {
__acquire(&t->lock);
}
thread->is_dead = true;
while (t) {
last_t = t;
active_transactions++;
binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
"release %d:%d transaction %d %s, still active\n",
proc->pid, thread->pid,
t->debug_id,
(t->to_thread == thread) ? "in" : "out");
if (t->to_thread == thread) {
t->to_proc = NULL;
t->to_thread = NULL;
if (t->buffer) {
t->buffer->transaction = NULL;
t->buffer = NULL;
}
t = t->to_parent;
} else if (t->from == thread) {
t->from = NULL;
t = t->from_parent;
} else
BUG();
spin_unlock(&last_t->lock);
if (t)
spin_lock(&t->lock);
else
__acquire(&t->lock);
}
/* annotation for sparse, lock not acquired in last iteration above */
__release(&t->lock);
/*
* If this thread used poll, make sure we remove the waitqueue
* from any epoll data structures holding it with POLLFREE.
* waitqueue_active() is safe to use here because we're holding
* the inner lock.
*/
if ((thread->looper & BINDER_LOOPER_STATE_POLL) &&
waitqueue_active(&thread->wait)) {
wake_up_poll(&thread->wait, EPOLLHUP | POLLFREE);
}
binder_inner_proc_unlock(thread->proc);
/*
* This is needed to avoid races between wake_up_poll() above and
* and ep_remove_waitqueue() called for other reasons (eg the epoll file
* descriptor being closed); ep_remove_waitqueue() holds an RCU read
* lock, so we can be sure it's done after calling synchronize_rcu().
*/
if (thread->looper & BINDER_LOOPER_STATE_POLL)
synchronize_rcu();
if (send_reply)
binder_send_failed_reply(send_reply, BR_DEAD_REPLY);
binder_release_work(proc, &thread->todo);
binder_thread_dec_tmpref(thread);
return active_transactions;
}
static __poll_t binder_poll(struct file *filp,
struct poll_table_struct *wait)
{
struct binder_proc *proc = filp->private_data;
struct binder_thread *thread = NULL;
bool wait_for_proc_work;
thread = binder_get_thread(proc);
if (!thread)
return POLLERR;
binder_inner_proc_lock(thread->proc);
thread->looper |= BINDER_LOOPER_STATE_POLL;
wait_for_proc_work = binder_available_for_proc_work_ilocked(thread);
binder_inner_proc_unlock(thread->proc);
poll_wait(filp, &thread->wait, wait);
if (binder_has_work(thread, wait_for_proc_work))
return EPOLLIN;
return 0;
}
static int binder_ioctl_write_read(struct file *filp,
unsigned int cmd, unsigned long arg,
struct binder_thread *thread)
{
int ret = 0;
struct binder_proc *proc = filp->private_data;
unsigned int size = _IOC_SIZE(cmd);
void __user *ubuf = (void __user *)arg;
struct binder_write_read bwr;
if (size != sizeof(struct binder_write_read)) {
ret = -EINVAL;
goto out;
}
if (copy_from_user(&bwr, ubuf, sizeof(bwr))) {
ret = -EFAULT;
goto out;
}
binder_debug(BINDER_DEBUG_READ_WRITE,
"%d:%d write %lld at %016llx, read %lld at %016llx\n",
proc->pid, thread->pid,
(u64)bwr.write_size, (u64)bwr.write_buffer,
(u64)bwr.read_size, (u64)bwr.read_buffer);
if (bwr.write_size > 0) {
ret = binder_thread_write(proc, thread,
bwr.write_buffer,
bwr.write_size,
&bwr.write_consumed);
trace_binder_write_done(ret);
if (ret < 0) {
bwr.read_consumed = 0;
if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
ret = -EFAULT;
goto out;
}
}
if (bwr.read_size > 0) {
ret = binder_thread_read(proc, thread, bwr.read_buffer,
bwr.read_size,
&bwr.read_consumed,
filp->f_flags & O_NONBLOCK);
trace_binder_read_done(ret);
binder_inner_proc_lock(proc);
if (!binder_worklist_empty_ilocked(&proc->todo))
binder_wakeup_proc_ilocked(proc);
binder_inner_proc_unlock(proc);
if (ret < 0) {
if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
ret = -EFAULT;
goto out;
}
}
binder_debug(BINDER_DEBUG_READ_WRITE,
"%d:%d wrote %lld of %lld, read return %lld of %lld\n",
proc->pid, thread->pid,
(u64)bwr.write_consumed, (u64)bwr.write_size,
(u64)bwr.read_consumed, (u64)bwr.read_size);
if (copy_to_user(ubuf, &bwr, sizeof(bwr))) {
ret = -EFAULT;
goto out;
}
out:
return ret;
}
static int binder_ioctl_set_ctx_mgr(struct file *filp)
{
int ret = 0;
struct binder_proc *proc = filp->private_data;
struct binder_context *context = proc->context;
struct binder_node *new_node;
kuid_t curr_euid = current_euid();
mutex_lock(&context->context_mgr_node_lock);
if (context->binder_context_mgr_node) {
pr_err("BINDER_SET_CONTEXT_MGR already set\n");
ret = -EBUSY;
goto out;
}
ret = security_binder_set_context_mgr(proc->tsk);
if (ret < 0)
goto out;
if (uid_valid(context->binder_context_mgr_uid)) {
if (!uid_eq(context->binder_context_mgr_uid, curr_euid)) {
pr_err("BINDER_SET_CONTEXT_MGR bad uid %d != %d\n",
from_kuid(&init_user_ns, curr_euid),
from_kuid(&init_user_ns,
context->binder_context_mgr_uid));
ret = -EPERM;
goto out;
}
} else {
context->binder_context_mgr_uid = curr_euid;
}
new_node = binder_new_node(proc, NULL);
if (!new_node) {
ret = -ENOMEM;
goto out;
}
binder_node_lock(new_node);
new_node->local_weak_refs++;
new_node->local_strong_refs++;
new_node->has_strong_ref = 1;
new_node->has_weak_ref = 1;
context->binder_context_mgr_node = new_node;
binder_node_unlock(new_node);
binder_put_node(new_node);
out:
mutex_unlock(&context->context_mgr_node_lock);
return ret;
}
static int binder_ioctl_get_node_info_for_ref(struct binder_proc *proc,
struct binder_node_info_for_ref *info)
{
struct binder_node *node;
struct binder_context *context = proc->context;
__u32 handle = info->handle;
if (info->strong_count || info->weak_count || info->reserved1 ||
info->reserved2 || info->reserved3) {
binder_user_error("%d BINDER_GET_NODE_INFO_FOR_REF: only handle may be non-zero.",
proc->pid);
return -EINVAL;
}
/* This ioctl may only be used by the context manager */
mutex_lock(&context->context_mgr_node_lock);
if (!context->binder_context_mgr_node ||
context->binder_context_mgr_node->proc != proc) {
mutex_unlock(&context->context_mgr_node_lock);
return -EPERM;
}
mutex_unlock(&context->context_mgr_node_lock);
node = binder_get_node_from_ref(proc, handle, true, NULL);
if (!node)
return -EINVAL;
info->strong_count = node->local_strong_refs +
node->internal_strong_refs;
info->weak_count = node->local_weak_refs;
binder_put_node(node);
return 0;
}
static int binder_ioctl_get_node_debug_info(struct binder_proc *proc,
struct binder_node_debug_info *info)
{
struct rb_node *n;
binder_uintptr_t ptr = info->ptr;
memset(info, 0, sizeof(*info));
binder_inner_proc_lock(proc);
for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) {
struct binder_node *node = rb_entry(n, struct binder_node,
rb_node);
if (node->ptr > ptr) {
info->ptr = node->ptr;
info->cookie = node->cookie;
info->has_strong_ref = node->has_strong_ref;
info->has_weak_ref = node->has_weak_ref;
break;
}
}
binder_inner_proc_unlock(proc);
return 0;
}
static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
int ret;
struct binder_proc *proc = filp->private_data;
struct binder_thread *thread;
unsigned int size = _IOC_SIZE(cmd);
void __user *ubuf = (void __user *)arg;
/*pr_info("binder_ioctl: %d:%d %x %lx\n",
proc->pid, current->pid, cmd, arg);*/
binder_selftest_alloc(&proc->alloc);
trace_binder_ioctl(cmd, arg);
ret = wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
if (ret)
goto err_unlocked;
thread = binder_get_thread(proc);
if (thread == NULL) {
ret = -ENOMEM;
goto err;
}
switch (cmd) {
case BINDER_WRITE_READ:
ret = binder_ioctl_write_read(filp, cmd, arg, thread);
if (ret)
goto err;
break;
case BINDER_SET_MAX_THREADS: {
int max_threads;
if (copy_from_user(&max_threads, ubuf,
sizeof(max_threads))) {
ret = -EINVAL;
goto err;
}
binder_inner_proc_lock(proc);
proc->max_threads = max_threads;
binder_inner_proc_unlock(proc);
break;
}
case BINDER_SET_CONTEXT_MGR:
ret = binder_ioctl_set_ctx_mgr(filp);
if (ret)
goto err;
break;
case BINDER_THREAD_EXIT:
binder_debug(BINDER_DEBUG_THREADS, "%d:%d exit\n",
proc->pid, thread->pid);
binder_thread_release(proc, thread);
thread = NULL;
break;
case BINDER_VERSION: {
struct binder_version __user *ver = ubuf;
if (size != sizeof(struct binder_version)) {
ret = -EINVAL;
goto err;
}
if (put_user(BINDER_CURRENT_PROTOCOL_VERSION,
&ver->protocol_version)) {
ret = -EINVAL;
goto err;
}
break;
}
case BINDER_GET_NODE_INFO_FOR_REF: {
struct binder_node_info_for_ref info;
if (copy_from_user(&info, ubuf, sizeof(info))) {
ret = -EFAULT;
goto err;
}
ret = binder_ioctl_get_node_info_for_ref(proc, &info);
if (ret < 0)
goto err;
if (copy_to_user(ubuf, &info, sizeof(info))) {
ret = -EFAULT;
goto err;
}
break;
}
case BINDER_GET_NODE_DEBUG_INFO: {
struct binder_node_debug_info info;
if (copy_from_user(&info, ubuf, sizeof(info))) {
ret = -EFAULT;
goto err;
}
ret = binder_ioctl_get_node_debug_info(proc, &info);
if (ret < 0)
goto err;
if (copy_to_user(ubuf, &info, sizeof(info))) {
ret = -EFAULT;
goto err;
}
break;
}
default:
ret = -EINVAL;
goto err;
}
ret = 0;
err:
if (thread)
thread->looper_need_return = false;
wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
if (ret && ret != -ERESTARTSYS)
pr_info("%d:%d ioctl %x %lx returned %d\n", proc->pid, current->pid, cmd, arg, ret);
err_unlocked:
trace_binder_ioctl_done(ret);
return ret;
}
static void binder_vma_open(struct vm_area_struct *vma)
{
struct binder_proc *proc = vma->vm_private_data;
binder_debug(BINDER_DEBUG_OPEN_CLOSE,
"%d open vm area %lx-%lx (%ld K) vma %lx pagep %lx\n",
proc->pid, vma->vm_start, vma->vm_end,
(vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
(unsigned long)pgprot_val(vma->vm_page_prot));
}
static void binder_vma_close(struct vm_area_struct *vma)
{
struct binder_proc *proc = vma->vm_private_data;
binder_debug(BINDER_DEBUG_OPEN_CLOSE,
"%d close vm area %lx-%lx (%ld K) vma %lx pagep %lx\n",
proc->pid, vma->vm_start, vma->vm_end,
(vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
(unsigned long)pgprot_val(vma->vm_page_prot));
binder_alloc_vma_close(&proc->alloc);
}
static vm_fault_t binder_vm_fault(struct vm_fault *vmf)
{
return VM_FAULT_SIGBUS;
}
static const struct vm_operations_struct binder_vm_ops = {
.open = binder_vma_open,
.close = binder_vma_close,
.fault = binder_vm_fault,
};
static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
{
int ret;
struct binder_proc *proc = filp->private_data;
const char *failure_string;
if (proc->tsk != current->group_leader)
return -EINVAL;
if ((vma->vm_end - vma->vm_start) > SZ_4M)
vma->vm_end = vma->vm_start + SZ_4M;
binder_debug(BINDER_DEBUG_OPEN_CLOSE,
"%s: %d %lx-%lx (%ld K) vma %lx pagep %lx\n",
__func__, proc->pid, vma->vm_start, vma->vm_end,
(vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
(unsigned long)pgprot_val(vma->vm_page_prot));
if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) {
ret = -EPERM;
failure_string = "bad vm_flags";
goto err_bad_arg;
}
vma->vm_flags |= VM_DONTCOPY | VM_MIXEDMAP;
vma->vm_flags &= ~VM_MAYWRITE;
vma->vm_ops = &binder_vm_ops;
vma->vm_private_data = proc;
ret = binder_alloc_mmap_handler(&proc->alloc, vma);
if (ret)
return ret;
return 0;
err_bad_arg:
pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
proc->pid, vma->vm_start, vma->vm_end, failure_string, ret);
return ret;
}
static int binder_open(struct inode *nodp, struct file *filp)
{
struct binder_proc *proc;
struct binder_device *binder_dev;
binder_debug(BINDER_DEBUG_OPEN_CLOSE, "%s: %d:%d\n", __func__,
current->group_leader->pid, current->pid);
proc = kzalloc(sizeof(*proc), GFP_KERNEL);
if (proc == NULL)
return -ENOMEM;
spin_lock_init(&proc->inner_lock);
spin_lock_init(&proc->outer_lock);
get_task_struct(current->group_leader);
proc->tsk = current->group_leader;
INIT_LIST_HEAD(&proc->todo);
proc->default_priority = task_nice(current);
/* binderfs stashes devices in i_private */
if (is_binderfs_device(nodp))
binder_dev = nodp->i_private;
else
binder_dev = container_of(filp->private_data,
struct binder_device, miscdev);
proc->context = &binder_dev->context;
binder_alloc_init(&proc->alloc);
binder_stats_created(BINDER_STAT_PROC);
proc->pid = current->group_leader->pid;
INIT_LIST_HEAD(&proc->delivered_death);
INIT_LIST_HEAD(&proc->waiting_threads);
filp->private_data = proc;
mutex_lock(&binder_procs_lock);
hlist_add_head(&proc->proc_node, &binder_procs);
mutex_unlock(&binder_procs_lock);
if (binder_debugfs_dir_entry_proc) {
char strbuf[11];
snprintf(strbuf, sizeof(strbuf), "%u", proc->pid);
/*
* proc debug entries are shared between contexts, so
* this will fail if the process tries to open the driver
* again with a different context. The priting code will
* anyway print all contexts that a given PID has, so this
* is not a problem.
*/
proc->debugfs_entry = debugfs_create_file(strbuf, 0444,
binder_debugfs_dir_entry_proc,
(void *)(unsigned long)proc->pid,
&proc_fops);
}
return 0;
}
static int binder_flush(struct file *filp, fl_owner_t id)
{
struct binder_proc *proc = filp->private_data;
binder_defer_work(proc, BINDER_DEFERRED_FLUSH);
return 0;
}
static void binder_deferred_flush(struct binder_proc *proc)
{
struct rb_node *n;
int wake_count = 0;
binder_inner_proc_lock(proc);
for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) {
struct binder_thread *thread = rb_entry(n, struct binder_thread, rb_node);
thread->looper_need_return = true;
if (thread->looper & BINDER_LOOPER_STATE_WAITING) {
wake_up_interruptible(&thread->wait);
wake_count++;
}
}
binder_inner_proc_unlock(proc);
binder_debug(BINDER_DEBUG_OPEN_CLOSE,
"binder_flush: %d woke %d threads\n", proc->pid,
wake_count);
}
static int binder_release(struct inode *nodp, struct file *filp)
{
struct binder_proc *proc = filp->private_data;
debugfs_remove(proc->debugfs_entry);
binder_defer_work(proc, BINDER_DEFERRED_RELEASE);
return 0;
}
static int binder_node_release(struct binder_node *node, int refs)
{
struct binder_ref *ref;
int death = 0;
struct binder_proc *proc = node->proc;
binder_release_work(proc, &node->async_todo);
binder_node_lock(node);
binder_inner_proc_lock(proc);
binder_dequeue_work_ilocked(&node->work);
/*
* The caller must have taken a temporary ref on the node,
*/
BUG_ON(!node->tmp_refs);
if (hlist_empty(&node->refs) && node->tmp_refs == 1) {
binder_inner_proc_unlock(proc);
binder_node_unlock(node);
binder_free_node(node);
return refs;
}
node->proc = NULL;
node->local_strong_refs = 0;
node->local_weak_refs = 0;
binder_inner_proc_unlock(proc);
spin_lock(&binder_dead_nodes_lock);
hlist_add_head(&node->dead_node, &binder_dead_nodes);
spin_unlock(&binder_dead_nodes_lock);
hlist_for_each_entry(ref, &node->refs, node_entry) {
refs++;
/*
* Need the node lock to synchronize
* with new notification requests and the
* inner lock to synchronize with queued
* death notifications.
*/
binder_inner_proc_lock(ref->proc);
if (!ref->death) {
binder_inner_proc_unlock(ref->proc);
continue;
}
death++;
BUG_ON(!list_empty(&ref->death->work.entry));
ref->death->work.type = BINDER_WORK_DEAD_BINDER;
binder_enqueue_work_ilocked(&ref->death->work,
&ref->proc->todo);
binder_wakeup_proc_ilocked(ref->proc);
binder_inner_proc_unlock(ref->proc);
}
binder_debug(BINDER_DEBUG_DEAD_BINDER,
"node %d now dead, refs %d, death %d\n",
node->debug_id, refs, death);
binder_node_unlock(node);
binder_put_node(node);
return refs;
}
static void binder_deferred_release(struct binder_proc *proc)
{
struct binder_context *context = proc->context;
struct rb_node *n;
int threads, nodes, incoming_refs, outgoing_refs, active_transactions;
mutex_lock(&binder_procs_lock);
hlist_del(&proc->proc_node);
mutex_unlock(&binder_procs_lock);
mutex_lock(&context->context_mgr_node_lock);
if (context->binder_context_mgr_node &&
context->binder_context_mgr_node->proc == proc) {
binder_debug(BINDER_DEBUG_DEAD_BINDER,
"%s: %d context_mgr_node gone\n",
__func__, proc->pid);
context->binder_context_mgr_node = NULL;
}
mutex_unlock(&context->context_mgr_node_lock);
binder_inner_proc_lock(proc);
/*
* Make sure proc stays alive after we
* remove all the threads
*/
proc->tmp_ref++;
proc->is_dead = true;
threads = 0;
active_transactions = 0;
while ((n = rb_first(&proc->threads))) {
struct binder_thread *thread;
thread = rb_entry(n, struct binder_thread, rb_node);
binder_inner_proc_unlock(proc);
threads++;
active_transactions += binder_thread_release(proc, thread);
binder_inner_proc_lock(proc);
}
nodes = 0;
incoming_refs = 0;
while ((n = rb_first(&proc->nodes))) {
struct binder_node *node;
node = rb_entry(n, struct binder_node, rb_node);
nodes++;
/*
* take a temporary ref on the node before
* calling binder_node_release() which will either
* kfree() the node or call binder_put_node()
*/
binder_inc_node_tmpref_ilocked(node);
rb_erase(&node->rb_node, &proc->nodes);
binder_inner_proc_unlock(proc);
incoming_refs = binder_node_release(node, incoming_refs);
binder_inner_proc_lock(proc);
}
binder_inner_proc_unlock(proc);
outgoing_refs = 0;
binder_proc_lock(proc);
while ((n = rb_first(&proc->refs_by_desc))) {
struct binder_ref *ref;
ref = rb_entry(n, struct binder_ref, rb_node_desc);
outgoing_refs++;
binder_cleanup_ref_olocked(ref);
binder_proc_unlock(proc);
binder_free_ref(ref);
binder_proc_lock(proc);
}
binder_proc_unlock(proc);
binder_release_work(proc, &proc->todo);
binder_release_work(proc, &proc->delivered_death);
binder_debug(BINDER_DEBUG_OPEN_CLOSE,
"%s: %d threads %d, nodes %d (ref %d), refs %d, active transactions %d\n",
__func__, proc->pid, threads, nodes, incoming_refs,
outgoing_refs, active_transactions);
binder_proc_dec_tmpref(proc);
}
static void binder_deferred_func(struct work_struct *work)
{
struct binder_proc *proc;
int defer;
do {
mutex_lock(&binder_deferred_lock);
if (!hlist_empty(&binder_deferred_list)) {
proc = hlist_entry(binder_deferred_list.first,
struct binder_proc, deferred_work_node);
hlist_del_init(&proc->deferred_work_node);
defer = proc->deferred_work;
proc->deferred_work = 0;
} else {
proc = NULL;
defer = 0;
}
mutex_unlock(&binder_deferred_lock);
if (defer & BINDER_DEFERRED_FLUSH)
binder_deferred_flush(proc);
if (defer & BINDER_DEFERRED_RELEASE)
binder_deferred_release(proc); /* frees proc */
} while (proc);
}
static DECLARE_WORK(binder_deferred_work, binder_deferred_func);
static void
binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer)
{
mutex_lock(&binder_deferred_lock);
proc->deferred_work |= defer;
if (hlist_unhashed(&proc->deferred_work_node)) {
hlist_add_head(&proc->deferred_work_node,
&binder_deferred_list);
schedule_work(&binder_deferred_work);
}
mutex_unlock(&binder_deferred_lock);
}
static void print_binder_transaction_ilocked(struct seq_file *m,
struct binder_proc *proc,
const char *prefix,
struct binder_transaction *t)
{
struct binder_proc *to_proc;
struct binder_buffer *buffer = t->buffer;
spin_lock(&t->lock);
to_proc = t->to_proc;
seq_printf(m,
"%s %d: %pK from %d:%d to %d:%d code %x flags %x pri %ld r%d",
prefix, t->debug_id, t,
t->from ? t->from->proc->pid : 0,
t->from ? t->from->pid : 0,
to_proc ? to_proc->pid : 0,
t->to_thread ? t->to_thread->pid : 0,
t->code, t->flags, t->priority, t->need_reply);
spin_unlock(&t->lock);
if (proc != to_proc) {
/*
* Can only safely deref buffer if we are holding the
* correct proc inner lock for this node
*/
seq_puts(m, "\n");
return;
}
if (buffer == NULL) {
seq_puts(m, " buffer free\n");
return;
}
if (buffer->target_node)
seq_printf(m, " node %d", buffer->target_node->debug_id);
seq_printf(m, " size %zd:%zd data %pK\n",
buffer->data_size, buffer->offsets_size,
buffer->data);
}
static void print_binder_work_ilocked(struct seq_file *m,
struct binder_proc *proc,
const char *prefix,
const char *transaction_prefix,
struct binder_work *w)
{
struct binder_node *node;
struct binder_transaction *t;
switch (w->type) {
case BINDER_WORK_TRANSACTION:
t = container_of(w, struct binder_transaction, work);
print_binder_transaction_ilocked(
m, proc, transaction_prefix, t);
break;
case BINDER_WORK_RETURN_ERROR: {
struct binder_error *e = container_of(
w, struct binder_error, work);
seq_printf(m, "%stransaction error: %u\n",
prefix, e->cmd);
} break;
case BINDER_WORK_TRANSACTION_COMPLETE:
seq_printf(m, "%stransaction complete\n", prefix);
break;
case BINDER_WORK_NODE:
node = container_of(w, struct binder_node, work);
seq_printf(m, "%snode work %d: u%016llx c%016llx\n",
prefix, node->debug_id,
(u64)node->ptr, (u64)node->cookie);
break;
case BINDER_WORK_DEAD_BINDER:
seq_printf(m, "%shas dead binder\n", prefix);
break;
case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
seq_printf(m, "%shas cleared dead binder\n", prefix);
break;
case BINDER_WORK_CLEAR_DEATH_NOTIFICATION:
seq_printf(m, "%shas cleared death notification\n", prefix);
break;
default:
seq_printf(m, "%sunknown work: type %d\n", prefix, w->type);
break;
}
}
static void print_binder_thread_ilocked(struct seq_file *m,
struct binder_thread *thread,
int print_always)
{
struct binder_transaction *t;
struct binder_work *w;
size_t start_pos = m->count;
size_t header_pos;
seq_printf(m, " thread %d: l %02x need_return %d tr %d\n",
thread->pid, thread->looper,
thread->looper_need_return,
atomic_read(&thread->tmp_ref));
header_pos = m->count;
t = thread->transaction_stack;
while (t) {
if (t->from == thread) {
print_binder_transaction_ilocked(m, thread->proc,
" outgoing transaction", t);
t = t->from_parent;
} else if (t->to_thread == thread) {
print_binder_transaction_ilocked(m, thread->proc,
" incoming transaction", t);
t = t->to_parent;
} else {
print_binder_transaction_ilocked(m, thread->proc,
" bad transaction", t);
t = NULL;
}
}
list_for_each_entry(w, &thread->todo, entry) {
print_binder_work_ilocked(m, thread->proc, " ",
" pending transaction", w);
}
if (!print_always && m->count == header_pos)
m->count = start_pos;
}
static void print_binder_node_nilocked(struct seq_file *m,
struct binder_node *node)
{
struct binder_ref *ref;
struct binder_work *w;
int count;
count = 0;
hlist_for_each_entry(ref, &node->refs, node_entry)
count++;
seq_printf(m, " node %d: u%016llx c%016llx hs %d hw %d ls %d lw %d is %d iw %d tr %d",
node->debug_id, (u64)node->ptr, (u64)node->cookie,
node->has_strong_ref, node->has_weak_ref,
node->local_strong_refs, node->local_weak_refs,
node->internal_strong_refs, count, node->tmp_refs);
if (count) {
seq_puts(m, " proc");
hlist_for_each_entry(ref, &node->refs, node_entry)
seq_printf(m, " %d", ref->proc->pid);
}
seq_puts(m, "\n");
if (node->proc) {
list_for_each_entry(w, &node->async_todo, entry)
print_binder_work_ilocked(m, node->proc, " ",
" pending async transaction", w);
}
}
static void print_binder_ref_olocked(struct seq_file *m,
struct binder_ref *ref)
{
binder_node_lock(ref->node);
seq_printf(m, " ref %d: desc %d %snode %d s %d w %d d %pK\n",
ref->data.debug_id, ref->data.desc,
ref->node->proc ? "" : "dead ",
ref->node->debug_id, ref->data.strong,
ref->data.weak, ref->death);
binder_node_unlock(ref->node);
}
static void print_binder_proc(struct seq_file *m,
struct binder_proc *proc, int print_all)
{
struct binder_work *w;
struct rb_node *n;
size_t start_pos = m->count;
size_t header_pos;
struct binder_node *last_node = NULL;
seq_printf(m, "proc %d\n", proc->pid);
seq_printf(m, "context %s\n", proc->context->name);
header_pos = m->count;
binder_inner_proc_lock(proc);
for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n))
print_binder_thread_ilocked(m, rb_entry(n, struct binder_thread,
rb_node), print_all);
for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) {
struct binder_node *node = rb_entry(n, struct binder_node,
rb_node);
if (!print_all && !node->has_async_transaction)
continue;
/*
* take a temporary reference on the node so it
* survives and isn't removed from the tree
* while we print it.
*/
binder_inc_node_tmpref_ilocked(node);
/* Need to drop inner lock to take node lock */
binder_inner_proc_unlock(proc);
if (last_node)
binder_put_node(last_node);
binder_node_inner_lock(node);
print_binder_node_nilocked(m, node);
binder_node_inner_unlock(node);
last_node = node;
binder_inner_proc_lock(proc);
}
binder_inner_proc_unlock(proc);
if (last_node)
binder_put_node(last_node);
if (print_all) {
binder_proc_lock(proc);
for (n = rb_first(&proc->refs_by_desc);
n != NULL;
n = rb_next(n))
print_binder_ref_olocked(m, rb_entry(n,
struct binder_ref,
rb_node_desc));
binder_proc_unlock(proc);
}
binder_alloc_print_allocated(m, &proc->alloc);
binder_inner_proc_lock(proc);
list_for_each_entry(w, &proc->todo, entry)
print_binder_work_ilocked(m, proc, " ",
" pending transaction", w);
list_for_each_entry(w, &proc->delivered_death, entry) {
seq_puts(m, " has delivered dead binder\n");
break;
}
binder_inner_proc_unlock(proc);
if (!print_all && m->count == header_pos)
m->count = start_pos;
}
static const char * const binder_return_strings[] = {
"BR_ERROR",
"BR_OK",
"BR_TRANSACTION",
"BR_REPLY",
"BR_ACQUIRE_RESULT",
"BR_DEAD_REPLY",
"BR_TRANSACTION_COMPLETE",
"BR_INCREFS",
"BR_ACQUIRE",
"BR_RELEASE",
"BR_DECREFS",
"BR_ATTEMPT_ACQUIRE",
"BR_NOOP",
"BR_SPAWN_LOOPER",
"BR_FINISHED",
"BR_DEAD_BINDER",
"BR_CLEAR_DEATH_NOTIFICATION_DONE",
"BR_FAILED_REPLY"
};
static const char * const binder_command_strings[] = {
"BC_TRANSACTION",
"BC_REPLY",
"BC_ACQUIRE_RESULT",
"BC_FREE_BUFFER",
"BC_INCREFS",
"BC_ACQUIRE",
"BC_RELEASE",
"BC_DECREFS",
"BC_INCREFS_DONE",
"BC_ACQUIRE_DONE",
"BC_ATTEMPT_ACQUIRE",
"BC_REGISTER_LOOPER",
"BC_ENTER_LOOPER",
"BC_EXIT_LOOPER",
"BC_REQUEST_DEATH_NOTIFICATION",
"BC_CLEAR_DEATH_NOTIFICATION",
"BC_DEAD_BINDER_DONE",
"BC_TRANSACTION_SG",
"BC_REPLY_SG",
};
static const char * const binder_objstat_strings[] = {
"proc",
"thread",
"node",
"ref",
"death",
"transaction",
"transaction_complete"
};
static void print_binder_stats(struct seq_file *m, const char *prefix,
struct binder_stats *stats)
{
int i;
BUILD_BUG_ON(ARRAY_SIZE(stats->bc) !=
ARRAY_SIZE(binder_command_strings));
for (i = 0; i < ARRAY_SIZE(stats->bc); i++) {
int temp = atomic_read(&stats->bc[i]);
if (temp)
seq_printf(m, "%s%s: %d\n", prefix,
binder_command_strings[i], temp);
}
BUILD_BUG_ON(ARRAY_SIZE(stats->br) !=
ARRAY_SIZE(binder_return_strings));
for (i = 0; i < ARRAY_SIZE(stats->br); i++) {
int temp = atomic_read(&stats->br[i]);
if (temp)
seq_printf(m, "%s%s: %d\n", prefix,
binder_return_strings[i], temp);
}
BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) !=
ARRAY_SIZE(binder_objstat_strings));
BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) !=
ARRAY_SIZE(stats->obj_deleted));
for (i = 0; i < ARRAY_SIZE(stats->obj_created); i++) {
int created = atomic_read(&stats->obj_created[i]);
int deleted = atomic_read(&stats->obj_deleted[i]);
if (created || deleted)
seq_printf(m, "%s%s: active %d total %d\n",
prefix,
binder_objstat_strings[i],
created - deleted,
created);
}
}
static void print_binder_proc_stats(struct seq_file *m,
struct binder_proc *proc)
{
struct binder_work *w;
struct binder_thread *thread;
struct rb_node *n;
int count, strong, weak, ready_threads;
size_t free_async_space =
binder_alloc_get_free_async_space(&proc->alloc);
seq_printf(m, "proc %d\n", proc->pid);
seq_printf(m, "context %s\n", proc->context->name);
count = 0;
ready_threads = 0;
binder_inner_proc_lock(proc);
for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n))
count++;
list_for_each_entry(thread, &proc->waiting_threads, waiting_thread_node)
ready_threads++;
seq_printf(m, " threads: %d\n", count);
seq_printf(m, " requested threads: %d+%d/%d\n"
" ready threads %d\n"
" free async space %zd\n", proc->requested_threads,
proc->requested_threads_started, proc->max_threads,
ready_threads,
free_async_space);
count = 0;
for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n))
count++;
binder_inner_proc_unlock(proc);
seq_printf(m, " nodes: %d\n", count);
count = 0;
strong = 0;
weak = 0;
binder_proc_lock(proc);
for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) {
struct binder_ref *ref = rb_entry(n, struct binder_ref,
rb_node_desc);
count++;
strong += ref->data.strong;
weak += ref->data.weak;
}
binder_proc_unlock(proc);
seq_printf(m, " refs: %d s %d w %d\n", count, strong, weak);
count = binder_alloc_get_allocated_count(&proc->alloc);
seq_printf(m, " buffers: %d\n", count);
binder_alloc_print_pages(m, &proc->alloc);
count = 0;
binder_inner_proc_lock(proc);
list_for_each_entry(w, &proc->todo, entry) {
if (w->type == BINDER_WORK_TRANSACTION)
count++;
}
binder_inner_proc_unlock(proc);
seq_printf(m, " pending transactions: %d\n", count);
print_binder_stats(m, " ", &proc->stats);
}
static int state_show(struct seq_file *m, void *unused)
{
struct binder_proc *proc;
struct binder_node *node;
struct binder_node *last_node = NULL;
seq_puts(m, "binder state:\n");
spin_lock(&binder_dead_nodes_lock);
if (!hlist_empty(&binder_dead_nodes))
seq_puts(m, "dead nodes:\n");
hlist_for_each_entry(node, &binder_dead_nodes, dead_node) {
/*
* take a temporary reference on the node so it
* survives and isn't removed from the list
* while we print it.
*/
node->tmp_refs++;
spin_unlock(&binder_dead_nodes_lock);
if (last_node)
binder_put_node(last_node);
binder_node_lock(node);
print_binder_node_nilocked(m, node);
binder_node_unlock(node);
last_node = node;
spin_lock(&binder_dead_nodes_lock);
}
spin_unlock(&binder_dead_nodes_lock);
if (last_node)
binder_put_node(last_node);
mutex_lock(&binder_procs_lock);
hlist_for_each_entry(proc, &binder_procs, proc_node)
print_binder_proc(m, proc, 1);
mutex_unlock(&binder_procs_lock);
return 0;
}
static int stats_show(struct seq_file *m, void *unused)
{
struct binder_proc *proc;
seq_puts(m, "binder stats:\n");
print_binder_stats(m, "", &binder_stats);
mutex_lock(&binder_procs_lock);
hlist_for_each_entry(proc, &binder_procs, proc_node)
print_binder_proc_stats(m, proc);
mutex_unlock(&binder_procs_lock);
return 0;
}
static int transactions_show(struct seq_file *m, void *unused)
{
struct binder_proc *proc;
seq_puts(m, "binder transactions:\n");
mutex_lock(&binder_procs_lock);
hlist_for_each_entry(proc, &binder_procs, proc_node)
print_binder_proc(m, proc, 0);
mutex_unlock(&binder_procs_lock);
return 0;
}
static int proc_show(struct seq_file *m, void *unused)
{
struct binder_proc *itr;
int pid = (unsigned long)m->private;
mutex_lock(&binder_procs_lock);
hlist_for_each_entry(itr, &binder_procs, proc_node) {
if (itr->pid == pid) {
seq_puts(m, "binder proc state:\n");
print_binder_proc(m, itr, 1);
}
}
mutex_unlock(&binder_procs_lock);
return 0;
}
static void print_binder_transaction_log_entry(struct seq_file *m,
struct binder_transaction_log_entry *e)
{
int debug_id = READ_ONCE(e->debug_id_done);
/*
* read barrier to guarantee debug_id_done read before
* we print the log values
*/
smp_rmb();
seq_printf(m,
"%d: %s from %d:%d to %d:%d context %s node %d handle %d size %d:%d ret %d/%d l=%d",
e->debug_id, (e->call_type == 2) ? "reply" :
((e->call_type == 1) ? "async" : "call "), e->from_proc,
e->from_thread, e->to_proc, e->to_thread, e->context_name,
e->to_node, e->target_handle, e->data_size, e->offsets_size,
e->return_error, e->return_error_param,
e->return_error_line);
/*
* read-barrier to guarantee read of debug_id_done after
* done printing the fields of the entry
*/
smp_rmb();
seq_printf(m, debug_id && debug_id == READ_ONCE(e->debug_id_done) ?
"\n" : " (incomplete)\n");
}
static int transaction_log_show(struct seq_file *m, void *unused)
{
struct binder_transaction_log *log = m->private;
unsigned int log_cur = atomic_read(&log->cur);
unsigned int count;
unsigned int cur;
int i;
count = log_cur + 1;
cur = count < ARRAY_SIZE(log->entry) && !log->full ?
0 : count % ARRAY_SIZE(log->entry);
if (count > ARRAY_SIZE(log->entry) || log->full)
count = ARRAY_SIZE(log->entry);
for (i = 0; i < count; i++) {
unsigned int index = cur++ % ARRAY_SIZE(log->entry);
print_binder_transaction_log_entry(m, &log->entry[index]);
}
return 0;
}
const struct file_operations binder_fops = {
.owner = THIS_MODULE,
.poll = binder_poll,
.unlocked_ioctl = binder_ioctl,
.compat_ioctl = binder_ioctl,
.mmap = binder_mmap,
.open = binder_open,
.flush = binder_flush,
.release = binder_release,
};
DEFINE_SHOW_ATTRIBUTE(state);
DEFINE_SHOW_ATTRIBUTE(stats);
DEFINE_SHOW_ATTRIBUTE(transactions);
DEFINE_SHOW_ATTRIBUTE(transaction_log);
static int __init init_binder_device(const char *name)
{
int ret;
struct binder_device *binder_device;
binder_device = kzalloc(sizeof(*binder_device), GFP_KERNEL);
if (!binder_device)
return -ENOMEM;
binder_device->miscdev.fops = &binder_fops;
binder_device->miscdev.minor = MISC_DYNAMIC_MINOR;
binder_device->miscdev.name = name;
binder_device->context.binder_context_mgr_uid = INVALID_UID;
binder_device->context.name = name;
mutex_init(&binder_device->context.context_mgr_node_lock);
ret = misc_register(&binder_device->miscdev);
if (ret < 0) {
kfree(binder_device);
return ret;
}
hlist_add_head(&binder_device->hlist, &binder_devices);
return ret;
}
static int __init binder_init(void)
{
int ret;
char *device_name, *device_names, *device_tmp;
struct binder_device *device;
struct hlist_node *tmp;
ret = binder_alloc_shrinker_init();
if (ret)
return ret;
atomic_set(&binder_transaction_log.cur, ~0U);
atomic_set(&binder_transaction_log_failed.cur, ~0U);
binder_debugfs_dir_entry_root = debugfs_create_dir("binder", NULL);
if (binder_debugfs_dir_entry_root)
binder_debugfs_dir_entry_proc = debugfs_create_dir("proc",
binder_debugfs_dir_entry_root);
if (binder_debugfs_dir_entry_root) {
debugfs_create_file("state",
0444,
binder_debugfs_dir_entry_root,
NULL,
&state_fops);
debugfs_create_file("stats",
0444,
binder_debugfs_dir_entry_root,
NULL,
&stats_fops);
debugfs_create_file("transactions",
0444,
binder_debugfs_dir_entry_root,
NULL,
&transactions_fops);
debugfs_create_file("transaction_log",
0444,
binder_debugfs_dir_entry_root,
&binder_transaction_log,
&transaction_log_fops);
debugfs_create_file("failed_transaction_log",
0444,
binder_debugfs_dir_entry_root,
&binder_transaction_log_failed,
&transaction_log_fops);
}
/*
* Copy the module_parameter string, because we don't want to
* tokenize it in-place.
*/
device_names = kstrdup(binder_devices_param, GFP_KERNEL);
if (!device_names) {
ret = -ENOMEM;
goto err_alloc_device_names_failed;
}
device_tmp = device_names;
while ((device_name = strsep(&device_tmp, ","))) {
ret = init_binder_device(device_name);
if (ret)
goto err_init_binder_device_failed;
}
return ret;
err_init_binder_device_failed:
hlist_for_each_entry_safe(device, tmp, &binder_devices, hlist) {
misc_deregister(&device->miscdev);
hlist_del(&device->hlist);
kfree(device);
}
kfree(device_names);
err_alloc_device_names_failed:
debugfs_remove_recursive(binder_debugfs_dir_entry_root);
return ret;
}
device_initcall(binder_init);
#define CREATE_TRACE_POINTS
#include "binder_trace.h"
MODULE_LICENSE("GPL v2");
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