diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c index 4946d282a35c..9e1a98a360d4 100644 --- a/drivers/staging/android/binder.c +++ b/drivers/staging/android/binder.c @@ -386,17 +386,8 @@ 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) { - struct files_struct *files = proc->files; - struct fdtable *fdt; - - if (files == NULL) - return; - - spin_lock(&files->file_lock); - fdt = files_fdtable(files); - BUG_ON(fdt->fd[fd] != NULL); - rcu_assign_pointer(fdt->fd[fd], file); - spin_unlock(&files->file_lock); + if (proc->files) + __fd_install(proc->files, fd, file); } /* diff --git a/fs/file.c b/fs/file.c index 78cf88f2a0e8..0d1bf0515111 100644 --- a/fs/file.c +++ b/fs/file.c @@ -599,11 +599,18 @@ EXPORT_SYMBOL(put_unused_fd); * * It should never happen - if we allow dup2() do it, _really_ bad things * will follow. + * + * NOTE: __fd_install() variant is really, really low-level; don't + * use it unless you are forced to by truly lousy API shoved down + * your throat. 'files' *MUST* be either current->files or obtained + * by get_files_struct(current) done by whoever had given it to you, + * or really bad things will happen. Normally you want to use + * fd_install() instead. */ -void fd_install(unsigned int fd, struct file *file) +void __fd_install(struct files_struct *files, unsigned int fd, + struct file *file) { - struct files_struct *files = current->files; struct fdtable *fdt; spin_lock(&files->file_lock); fdt = files_fdtable(files); @@ -612,4 +619,9 @@ void fd_install(unsigned int fd, struct file *file) spin_unlock(&files->file_lock); } +void fd_install(unsigned int fd, struct file *file) +{ + __fd_install(current->files, fd, file); +} + EXPORT_SYMBOL(fd_install); diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h index 3855f4febe70..59d4fc7f10c8 100644 --- a/include/linux/fdtable.h +++ b/include/linux/fdtable.h @@ -121,6 +121,8 @@ struct files_struct *dup_fd(struct files_struct *, int *); extern int __alloc_fd(struct files_struct *files, unsigned start, unsigned end, unsigned flags); +extern void __fd_install(struct files_struct *files, + unsigned int fd, struct file *file); extern struct kmem_cache *files_cachep;