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author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-01-02 14:46:35 +0100 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-01-02 14:46:35 +0100 |
commit | b6a09416e83ffe4eccfb4ef1b91b3b66483fa810 (patch) | |
tree | b30f266e85047244dcdb47d5afc134e76aec530d /drivers/android/binder.c | |
parent | db809859c8cee415293b830e67178f526d1eb2be (diff) | |
parent | 30a7acd573899fd8b8ac39236eff6468b195ac7d (diff) | |
download | linux-stable-b6a09416e83ffe4eccfb4ef1b91b3b66483fa810.tar.gz linux-stable-b6a09416e83ffe4eccfb4ef1b91b3b66483fa810.tar.bz2 linux-stable-b6a09416e83ffe4eccfb4ef1b91b3b66483fa810.zip |
Merge 4.15-rc6 into char-misc-next
We want the fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/android/binder.c')
-rw-r--r-- | drivers/android/binder.c | 44 |
1 files changed, 31 insertions, 13 deletions
diff --git a/drivers/android/binder.c b/drivers/android/binder.c index a54a0f1f69a9..778caed570c6 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -482,7 +482,8 @@ enum binder_deferred_state { * @tsk task_struct for group_leader of process * (invariant after initialized) * @files files_struct for process - * (invariant after initialized) + * (protected by @files_lock) + * @files_lock mutex to protect @files * @deferred_work_node: element for binder_deferred_list * (protected by binder_deferred_lock) * @deferred_work: bitmap of deferred work to perform @@ -530,6 +531,7 @@ struct binder_proc { int pid; struct task_struct *tsk; struct files_struct *files; + struct mutex files_lock; struct hlist_node deferred_work_node; int deferred_work; bool is_dead; @@ -924,20 +926,26 @@ static void binder_inc_node_tmpref_ilocked(struct binder_node *node); static int task_get_unused_fd_flags(struct binder_proc *proc, int flags) { - struct files_struct *files = proc->files; unsigned long rlim_cur; unsigned long irqs; + int ret; - if (files == NULL) - return -ESRCH; - - if (!lock_task_sighand(proc->tsk, &irqs)) - return -EMFILE; - + mutex_lock(&proc->files_lock); + if (proc->files == NULL) { + ret = -ESRCH; + goto err; + } + if (!lock_task_sighand(proc->tsk, &irqs)) { + ret = -EMFILE; + goto err; + } rlim_cur = task_rlimit(proc->tsk, RLIMIT_NOFILE); unlock_task_sighand(proc->tsk, &irqs); - return __alloc_fd(files, 0, rlim_cur, flags); + ret = __alloc_fd(proc->files, 0, rlim_cur, flags); +err: + mutex_unlock(&proc->files_lock); + return ret; } /* @@ -946,8 +954,10 @@ static int task_get_unused_fd_flags(struct binder_proc *proc, int flags) static void task_fd_install( struct binder_proc *proc, unsigned int fd, struct file *file) { + mutex_lock(&proc->files_lock); if (proc->files) __fd_install(proc->files, fd, file); + mutex_unlock(&proc->files_lock); } /* @@ -957,9 +967,11 @@ static long task_close_fd(struct binder_proc *proc, unsigned int fd) { int retval; - if (proc->files == NULL) - return -ESRCH; - + mutex_lock(&proc->files_lock); + if (proc->files == NULL) { + retval = -ESRCH; + goto err; + } retval = __close_fd(proc->files, fd); /* can't restart close syscall because file table entry was cleared */ if (unlikely(retval == -ERESTARTSYS || @@ -967,7 +979,8 @@ static long task_close_fd(struct binder_proc *proc, unsigned int fd) retval == -ERESTARTNOHAND || retval == -ERESTART_RESTARTBLOCK)) retval = -EINTR; - +err: + mutex_unlock(&proc->files_lock); return retval; } @@ -4690,7 +4703,9 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma) ret = binder_alloc_mmap_handler(&proc->alloc, vma); if (ret) return ret; + mutex_lock(&proc->files_lock); proc->files = get_files_struct(current); + mutex_unlock(&proc->files_lock); return 0; err_bad_arg: @@ -4714,6 +4729,7 @@ static int binder_open(struct inode *nodp, struct file *filp) spin_lock_init(&proc->outer_lock); get_task_struct(current->group_leader); proc->tsk = current->group_leader; + mutex_init(&proc->files_lock); INIT_LIST_HEAD(&proc->todo); proc->default_priority = task_nice(current); binder_dev = container_of(filp->private_data, struct binder_device, @@ -4966,9 +4982,11 @@ static void binder_deferred_func(struct work_struct *work) files = NULL; if (defer & BINDER_DEFERRED_PUT_FILES) { + mutex_lock(&proc->files_lock); files = proc->files; if (files) proc->files = NULL; + mutex_unlock(&proc->files_lock); } if (defer & BINDER_DEFERRED_FLUSH) |