Merge tag 'devprop-4.21-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafae...

[linux.git] / fs / file.c

diff --git a/fs/file.c b/fs/file.c
index 50304c7525eae83ba9505e6994b561b5f07b8bae..3209ee271c41d15f0138164fd822e236e5125560 100644 (file)
--- a/fs/file.c
+++ b/fs/file.c
@@ -640,6 +640,35 @@ out_unlock:
 }
 EXPORT_SYMBOL(__close_fd); /* for ksys_close() */
 
+/*
+ * variant of __close_fd that gets a ref on the file for later fput
+ */
+int __close_fd_get_file(unsigned int fd, struct file **res)
+{
+       struct files_struct *files = current->files;
+       struct file *file;
+       struct fdtable *fdt;
+
+       spin_lock(&files->file_lock);
+       fdt = files_fdtable(files);
+       if (fd >= fdt->max_fds)
+               goto out_unlock;
+       file = fdt->fd[fd];
+       if (!file)
+               goto out_unlock;
+       rcu_assign_pointer(fdt->fd[fd], NULL);
+       __put_unused_fd(files, fd);
+       spin_unlock(&files->file_lock);
+       get_file(file);
+       *res = file;
+       return filp_close(file, files);
+
+out_unlock:
+       spin_unlock(&files->file_lock);
+       *res = NULL;
+       return -ENOENT;
+}
+
 void do_close_on_exec(struct files_struct *files)
 {
        unsigned i;