From patchwork Wed May 12 14:46:04 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: 436979 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 609E9C43611 for ; Wed, 12 May 2021 15:32:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4499C61CD6 for ; Wed, 12 May 2021 15:32:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234599AbhELPdU (ORCPT ); Wed, 12 May 2021 11:33:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:40900 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235679AbhELP2q (ORCPT ); Wed, 12 May 2021 11:28:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id AECE66192C; Wed, 12 May 2021 15:14:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620832486; bh=ME+o8qVmDRw6Mq9SpL5ndvS2yjgea2XcS6Yz5PbfQF0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vEVBak5rP8Io7mthF3AkRtW73Ex4YZ/4scDfnf2cHvNXP2kZnPUopU09+tmTY/eqN PS3CNslDa9JWmn81HQePtmVRcKUTx/7jFRTga0eldggazKXOic1u8z+yZB7JNRvnyk 7+jfnU5vX6s3g2/po0sy2DvuidZ2SLNngdN7EUA8= 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 5.10 254/530] m68k: Add missing mmap_read_lock() to sys_cacheflush() Date: Wed, 12 May 2021 16:46:04 +0200 Message-Id: <20210512144828.185791552@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144819.664462530@linuxfoundation.org> References: <20210512144819.664462530@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;