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 238CAC4332B for ; Wed, 18 Mar 2020 21:08:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E4643208CA for ; Wed, 18 Mar 2020 21:08:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584565687; bh=0geW2N5yklwjKb6rivq1v7IxgkL4xJnOpRV3pgTthvg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=LLmckcP33zQanuFG7oWn201URpWeOaWUrwhpF67V33nGSMGhbJDKS1K1rW3vFwn3K 4cuvEGscguY+EamAV4pHgUfOl6lHE7U/9SraDbTFpNntfTMqoga2REcMcLjtJPCesM ijWqWRSBcN5YlOWFAWwfV6+zS6g8ptqbsaSdkk48= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727571AbgCRUyI (ORCPT ); Wed, 18 Mar 2020 16:54:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:53508 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727562AbgCRUyI (ORCPT ); Wed, 18 Mar 2020 16:54:08 -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 BA5BA208E4; Wed, 18 Mar 2020 20:54:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584564847; bh=0geW2N5yklwjKb6rivq1v7IxgkL4xJnOpRV3pgTthvg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WP39XUgrySw46+NnDtGuF3S5N0/h7hM+2w0wipJ4OzloiEwWsG6C0GN/NKJ7qZKb6 L9ROFnGf2hR+DRhjDOpxTHZU9rZqnSclx8rRh/tXymKAQWAz8ntk0+LTpROrA1HgFM ZtO3OIuEMV31o8/hWhwEjotYxnMonACcQq+o1FFQ= 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 5.4 25/73] cgroup1: don't call release_agent when it is "" Date: Wed, 18 Mar 2020 16:52:49 -0400 Message-Id: <20200318205337.16279-25-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200318205337.16279-1-sashal@kernel.org> References: <20200318205337.16279-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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 2db582706ec5c..f684c82efc2ea 100644 --- a/kernel/cgroup/cgroup-v1.c +++ b/kernel/cgroup/cgroup-v1.c @@ -784,7 +784,7 @@ 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