From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751209AbdBBNX2 (ORCPT ); Thu, 2 Feb 2017 08:23:28 -0500 Received: from www262.sakura.ne.jp ([202.181.97.72]:59240 "EHLO www262.sakura.ne.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750873AbdBBNXZ (ORCPT ); Thu, 2 Feb 2017 08:23:25 -0500 From: Tetsuo Handa To: akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, Tetsuo Handa , Oleg Nesterov Subject: [PATCH 1/2] block: Use for_each_thread() in sys_ioprio_set()/sys_ioprio_get() Date: Thu, 2 Feb 2017 22:22:58 +0900 Message-Id: <1486041779-4401-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> X-Mailer: git-send-email 1.8.3.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org IOPRIO_WHO_USER case in sys_ioprio_set()/sys_ioprio_get() are using while_each_thread(), which is unsafe under RCU lock according to commit 0c740d0afc3bff0a ("introduce for_each_thread() to replace the buggy while_each_thread()"). Use for_each_thread() which is safe under RCU lock. Link: http://lkml.kernel.org/r/201702011947.DBD56740.OMVHOLOtSJFFFQ@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa Cc: Oleg Nesterov --- block/ioprio.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/block/ioprio.c b/block/ioprio.c index 01b8116..3790669 100644 --- a/block/ioprio.c +++ b/block/ioprio.c @@ -122,14 +122,14 @@ int set_task_ioprio(struct task_struct *task, int ioprio) if (!user) break; - do_each_thread(g, p) { + for_each_process_thread(g, p) { if (!uid_eq(task_uid(p), uid) || !task_pid_vnr(p)) continue; ret = set_task_ioprio(p, ioprio); if (ret) goto free_uid; - } while_each_thread(g, p); + } free_uid: if (who) free_uid(user); @@ -222,7 +222,7 @@ int ioprio_best(unsigned short aprio, unsigned short bprio) if (!user) break; - do_each_thread(g, p) { + for_each_process_thread(g, p) { if (!uid_eq(task_uid(p), user->uid) || !task_pid_vnr(p)) continue; @@ -233,7 +233,7 @@ int ioprio_best(unsigned short aprio, unsigned short bprio) ret = tmpio; else ret = ioprio_best(ret, tmpio); - } while_each_thread(g, p); + } if (who) free_uid(user); -- 1.8.3.1