From patchwork Wed May 12 14:44:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 436766 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 C527FC43619 for ; Wed, 12 May 2021 16:07:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 078DE61985 for ; Wed, 12 May 2021 16:07:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237904AbhELQEU (ORCPT ); Wed, 12 May 2021 12:04:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:48160 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235387AbhELP7m (ORCPT ); Wed, 12 May 2021 11:59:42 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id EBC3C6197B; Wed, 12 May 2021 15:32:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620833540; bh=sBEwm+uHlyVNF45BaxNuJHaixHJpYJV7yDlSlaGqhwU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BHjjEb3pvHKxj7LvnKVAZ2Qlw7s05b0J6I6Pp4TzLvPZu7CUsEoIALhIqRa90kaiQ 1d2MtELUyyIbssJ5tKyr86yLONa484CGCifAzfI2/ztyxK+spwGosFC4nVud5kEAVJ iDrosrE8aMKg8q5FoBft9CZzHRGPKzObm81q+d84= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Christoph Hellwig , Rasmus Villemoes , Sasha Levin Subject: [PATCH 5.11 191/601] devtmpfs: fix placement of complete() call Date: Wed, 12 May 2021 16:44:28 +0200 Message-Id: <20210512144834.122538521@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144827.811958675@linuxfoundation.org> References: <20210512144827.811958675@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Rasmus Villemoes [ Upstream commit 38f087de8947700d3b06d3d1594490e0f611c5d1 ] Calling complete() from within the __init function is wrong - theoretically, the init process could proceed all the way to freeing the init mem before the devtmpfsd thread gets to execute the return instruction in devtmpfs_setup(). In practice, it seems to be harmless as gcc inlines devtmpfs_setup() into devtmpfsd(). So the calls of the __init functions init_chdir() etc. actually happen from devtmpfs_setup(), but the __ref on that one silences modpost (it's all right, because those calls happen before the complete()). But it does make the __init annotation of the setup function moot, which we'll fix in a subsequent patch. Fixes: bcbacc4909f1 ("devtmpfs: refactor devtmpfsd()") Reviewed-by: Christoph Hellwig Signed-off-by: Rasmus Villemoes Link: https://lore.kernel.org/r/20210312103027.2701413-1-linux@rasmusvillemoes.dk Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/base/devtmpfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c index eac184e6d657..a71d14117943 100644 --- a/drivers/base/devtmpfs.c +++ b/drivers/base/devtmpfs.c @@ -416,7 +416,6 @@ static int __init devtmpfs_setup(void *p) init_chroot("."); out: *(int *)p = err; - complete(&setup_done); return err; } @@ -429,6 +428,7 @@ static int __ref devtmpfsd(void *p) { int err = devtmpfs_setup(p); + complete(&setup_done); if (err) return err; devtmpfs_work_loop();