[PATCH] sanitize unshare_files/reset_files_struct

* let unshare_files() give caller the displaced files_struct
* don't bother with grabbing reference only to drop it in the
  caller if it hadn't been shared in the first place
* in that form unshare_files() is trivially implemented via
  unshare_fd(), so we eliminate the duplicate logics in fork.c
* reset_files_struct() is not just only called for current;
  it will break the system if somebody ever calls it for anything
  else (we can't modify ->files of somebody else).  Lose the
  task_struct * argument.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 2 insertions, 1 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index 3d320003cc03..97f609f574b1 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -507,8 +507,9 @@ void put_files_struct(struct files_struct *files)
 	}
 }
 
-void reset_files_struct(struct task_struct *tsk, struct files_struct *files)
+void reset_files_struct(struct files_struct *files)
 {
+	struct task_struct *tsk = current;
 	struct files_struct *old;
 
 	old = tsk->files;