From patchwork Wed May 12 14:46:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 438289 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 86AEFC43616 for ; Wed, 12 May 2021 16:12:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6994B61E5A for ; Wed, 12 May 2021 16:12:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234746AbhELQNB (ORCPT ); Wed, 12 May 2021 12:13:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:34634 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239110AbhELQHW (ORCPT ); Wed, 12 May 2021 12:07:22 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id ACEC961C3A; Wed, 12 May 2021 15:36:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620833779; bh=ME+o8qVmDRw6Mq9SpL5ndvS2yjgea2XcS6Yz5PbfQF0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZrWH0NCW0UUyx8XXaEDkQJUpENwROHiBUEZ/zYUQEk63QgczguPcT4CN6GKFE4GcD iSKcZ9lcwNlZgYLsEgojG2eCP2qi6rObxeoH/7pvAAhvsgKeU8rEV2Md/0NUJzYMhQ GePIYUyIqEXh6MjiHMsgCTCDOSX9bycculvdhDVY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Liam R. Howlett" , "Matthew Wilcox (Oracle)" , Geert Uytterhoeven , Sasha Levin Subject: [PATCH 5.11 284/601] m68k: Add missing mmap_read_lock() to sys_cacheflush() Date: Wed, 12 May 2021 16:46:01 +0200 Message-Id: <20210512144837.165035545@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: Liam Howlett [ Upstream commit f829b4b212a315b912cb23fd10aaf30534bb5ce9 ] When the superuser flushes the entire cache, the mmap_read_lock() is not taken, but mmap_read_unlock() is called. Add the missing mmap_read_lock() call. Fixes: cd2567b6850b1648 ("m68k: call find_vma with the mmap_sem held in sys_cacheflush()") Signed-off-by: Liam R. Howlett Reviewed-by: Matthew Wilcox (Oracle) Link: https://lore.kernel.org/r/20210407200032.764445-1-Liam.Howlett@Oracle.com Signed-off-by: Geert Uytterhoeven Signed-off-by: Sasha Levin --- arch/m68k/kernel/sys_m68k.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/m68k/kernel/sys_m68k.c b/arch/m68k/kernel/sys_m68k.c index 1c235d8f53f3..f55bdcb8e4f1 100644 --- a/arch/m68k/kernel/sys_m68k.c +++ b/arch/m68k/kernel/sys_m68k.c @@ -388,6 +388,8 @@ sys_cacheflush (unsigned long addr, int scope, int cache, unsigned long len) ret = -EPERM; if (!capable(CAP_SYS_ADMIN)) goto out; + + mmap_read_lock(current->mm); } else { struct vm_area_struct *vma;