From nobody Tue Sep 16 14:08:53 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6768CC4708D for ; Mon, 2 Jan 2023 15:53:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236348AbjABPx2 (ORCPT ); Mon, 2 Jan 2023 10:53:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232107AbjABPxZ (ORCPT ); Mon, 2 Jan 2023 10:53:25 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3809AB82; Mon, 2 Jan 2023 07:53:24 -0800 (PST) Date: Mon, 02 Jan 2023 15:53:20 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1672674801; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3P5pISwMYBYCrQ8Yr86Uym3gj8BN/L8IIlaMxfkhy08=; b=WDIaj39zarkxIy3RcXAEsQNsau423KjE7KQGAePWyn2aHanx9EtNzS9QA/UuUQq7qwccw7 zbvJ3sYAi4ReSi1N+H3FOs+IAyQo97tSiIkkNz8wtGdinUMWLFRWxGuq1b5DDSGpfUbCQW kFaVmDr39u610okCyxBAKADRvr6VS7khx2vYx5SU/tTS1orbO/QKjbV0DHkpPd+KBvDxeW aFMf66M+Mq0US/F/6+GR7INgIMoFzP5wlyLNbRoyYANMt+u+TvJFXhws8VZl2ZmejV1DEL DOMX6XAgG8CQZGlgvhmopnzgEJAzbBzwROZZSpTIzoIlOgMarV//96i9wekTxA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1672674801; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3P5pISwMYBYCrQ8Yr86Uym3gj8BN/L8IIlaMxfkhy08=; b=lXFeWHI9Gp0KHaqnUtDDEMeHEE750GwMn4AA+3SZWgZVPNAov8+TElRUZJGJyihCOvdXq6 8anhNCCiB1WxDABQ== From: "tip-bot2 for Mathieu Desnoyers" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] sched/rseq: Fix concurrency ID handling of usermodehelper kthreads Cc: kernel test robot , Borislav Petkov , Mathieu Desnoyers , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <202212301353.5c959d72-yujie.liu@intel.com> References: <202212301353.5c959d72-yujie.liu@intel.com> MIME-Version: 1.0 Message-ID: <167267480086.4906.14665352998737768536.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the sched/core branch of tip: Commit-ID: bbd0b031509b880b4e9a880bb27ca2a30ad081ab Gitweb: https://git.kernel.org/tip/bbd0b031509b880b4e9a880bb27ca2a30= ad081ab Author: Mathieu Desnoyers AuthorDate: Mon, 02 Jan 2023 10:12:16 -05:00 Committer: Borislav Petkov (AMD) CommitterDate: Mon, 02 Jan 2023 16:34:12 +01:00 sched/rseq: Fix concurrency ID handling of usermodehelper kthreads sched_mm_cid_after_execve() does not expect NULL t->mm, but it may happen if a usermodehelper kthread fails when attempting to execute a binary. sched_mm_cid_fork() can be issued from a usermodehelper kthread, which has t->flags PF_KTHREAD set. Fixes: af7f588d8f73 ("sched: Introduce per-memory-map concurrency ID") Reported-by: kernel test robot Reported-by: Borislav Petkov Signed-off-by: Mathieu Desnoyers Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/oe-lkp/202212301353.5c959d72-yujie.liu@intel.= com --- kernel/sched/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 048ec24..f99ee69 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -11343,8 +11343,8 @@ void sched_mm_cid_after_execve(struct task_struct *= t) struct mm_struct *mm =3D t->mm; unsigned long flags; =20 - WARN_ON_ONCE((t->flags & PF_KTHREAD) || !t->mm); - + if (!mm) + return; local_irq_save(flags); t->mm_cid =3D mm_cid_get(mm); t->mm_cid_active =3D 1; @@ -11354,7 +11354,7 @@ void sched_mm_cid_after_execve(struct task_struct *= t) =20 void sched_mm_cid_fork(struct task_struct *t) { - WARN_ON_ONCE((t->flags & PF_KTHREAD) || !t->mm || t->mm_cid !=3D -1); + WARN_ON_ONCE(!t->mm || t->mm_cid !=3D -1); t->mm_cid_active =3D 1; } #endif