exec: Move io_uring_task_cancel after the point of no return

Now that unshare_files happens in begin_new_exec after the point of no
return, io_uring_task_cancel can also happen later.

Effectively this means io_uring activities for a task are only canceled
when exec succeeds.

Link: https://lkml.kernel.org/r/878saih2op.fsf@x220.int.ebiederm.org
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

fs/exec.c

@@ -1257,6 +1257,11 @@ int begin_new_exec(struct linux_binprm * bprm)
 	if (retval)
 		goto out;
 
+	/*
+	 * Cancel any io_uring activity across execve
+	 */
+	io_uring_task_cancel();
+
 	/* Ensure the files table is not shared. */
 	retval = unshare_files();
 	if (retval)
@@ -1783,11 +1788,6 @@ static int bprm_execve(struct linux_binprm *bprm,
 	struct file *file;
 	int retval;
 
-	/*
-	 * Cancel any io_uring activity across execve
-	 */
-	io_uring_task_cancel();
-
 	retval = prepare_bprm_creds(bprm);
 	if (retval)
 		return retval;