From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46C6CC4332D for ; Wed, 18 Mar 2020 21:03:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 06FD220409 for ; Wed, 18 Mar 2020 21:03:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584565405; bh=CZB+KZiYdArxmr34T50wC1U0sriUX3k/RvRcHsuKGS4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=lXOUQh5tUHXBDIkXFUdDmP52qbNR0a34V2j4MScozb/tqjTURLdDXAfiPP4c1vNlm nfkW0EH8/6kPP4fT2AM4ZEGXkv5ECVcPrdtzIinc0eFTerTyapeWfVFocUjBWITPad nerzjp9fLkzHvQ6jB/w1NnxgMdzjMNLGAQVKY5Jg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727534AbgCRUzi (ORCPT ); Wed, 18 Mar 2020 16:55:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:55998 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728348AbgCRUzd (ORCPT ); Wed, 18 Mar 2020 16:55:33 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 12B3D20BED; Wed, 18 Mar 2020 20:55:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584564932; bh=CZB+KZiYdArxmr34T50wC1U0sriUX3k/RvRcHsuKGS4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=phPvVC6O5fVNmxyP1UYkBIAzD33fMGIIHF8aPMjiVW0dLx/sI+pQnHDVA0uGSNGWb 1KSdtD8d9ap4om8glS8LVf7/mePVgsW/XS9vbyBY5sRbEoB0/qdUTPtPHqMUGl5FKv b98hzqeK7owxdsupzgerKz/diFpjzi28YhnnWdYs= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Tycho Andersen , Tejun Heo , Sasha Levin , cgroups@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 19/37] cgroup1: don't call release_agent when it is "" Date: Wed, 18 Mar 2020 16:54:51 -0400 Message-Id: <20200318205509.17053-19-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200318205509.17053-1-sashal@kernel.org> References: <20200318205509.17053-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tycho Andersen [ Upstream commit 2e5383d7904e60529136727e49629a82058a5607 ] Older (and maybe current) versions of systemd set release_agent to "" when shutting down, but do not set notify_on_release to 0. Since 64e90a8acb85 ("Introduce STATIC_USERMODEHELPER to mediate call_usermodehelper()"), we filter out such calls when the user mode helper path is "". However, when used in conjunction with an actual (i.e. non "") STATIC_USERMODEHELPER, the path is never "", so the real usermode helper will be called with argv[0] == "". Let's avoid this by not invoking the release_agent when it is "". Signed-off-by: Tycho Andersen Signed-off-by: Tejun Heo Signed-off-by: Sasha Levin --- kernel/cgroup/cgroup-v1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c index c9628b9a41d23..dd8bdbfbbde1e 100644 --- a/kernel/cgroup/cgroup-v1.c +++ b/kernel/cgroup/cgroup-v1.c @@ -812,7 +812,7 @@ void cgroup1_release_agent(struct work_struct *work) pathbuf = kmalloc(PATH_MAX, GFP_KERNEL); agentbuf = kstrdup(cgrp->root->release_agent_path, GFP_KERNEL); - if (!pathbuf || !agentbuf) + if (!pathbuf || !agentbuf || !strlen(agentbuf)) goto out; spin_lock_irq(&css_set_lock); -- 2.20.1