exec: Only compute current once in flush_old_exec

Make it clear that current only needs to be computed once in
flush_old_exec.  This may have some efficiency improvements and it
makes the code easier to change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

diff --git a/fs/exec.c b/fs/exec.c
index db17be5..c3f3479 100644 (file)
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1260,13 +1260,14 @@ void __set_task_comm(struct task_struct *tsk, const char *buf, bool exec)
  */
 int flush_old_exec(struct linux_binprm * bprm)
 {
+       struct task_struct *me = current;
        int retval;
 
        /*
         * Make sure we have a private signal table and that
         * we are unassociated from the previous thread group.
         */
-       retval = de_thread(current);
+       retval = de_thread(me);
        if (retval)
                goto out;
 
@@ -1294,10 +1295,10 @@ int flush_old_exec(struct linux_binprm * bprm)
        bprm->mm = NULL;
 
        set_fs(USER_DS);
-       current->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD |
+       me->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD |
                                        PF_NOFREEZE | PF_NO_SETAFFINITY);
        flush_thread();
-       current->personality &= ~bprm->per_clear;
+       me->personality &= ~bprm->per_clear;
 
        /*
         * We have to apply CLOEXEC before we change whether the process is
@@ -1305,7 +1306,7 @@ int flush_old_exec(struct linux_binprm * bprm)
         * trying to access the should-be-closed file descriptors of a process
         * undergoing exec(2).
         */
-       do_close_on_exec(current->files);
+       do_close_on_exec(me->files);
        return 0;
 
 out: