From patchwork Tue Dec 1 07:45:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Rapoport X-Patchwork-Id: 11942077 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=-18.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 17AA1C64E7A for ; Tue, 1 Dec 2020 07:49:48 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 84A532085B for ; Tue, 1 Dec 2020 07:49:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="SCMP9nPp"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="k6EYvST4" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 84A532085B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=JSZCJl6OyNyuJYyKQ/AZmBdLq/mlHdWOY3P77QT5cds=; b=SCMP9nPpWPqoBGvrraJXssjMI RMIJVuHkI32iup5BBZEX1Qw96eRm24fNcT1STZyWjKT/NOs55r1Gj5PZTQAtDclA13ylWERTMnmVV rTFVXHN91YNInFmDNVSJD2uCbUfj4Kqd9SZ6VBFNZZF2ozv/ejWNc4runyAl9CyKzAcsydHYWY0St nTZnr4Ae8ujPfgyqVyhTDwMhC97b0udAsCz6qZrv1eSN38g2pa22i1ZyAaViq+tpBV8b427HPXi39 1W/VnUX3X7T/NlZAnUp89q4dc2ypOitBPQoLC15w4rYAuSG1jhpFUcYqvkyRJ8OqW9QF3/6hEc6hT PWjFpoDkQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kk0Oi-00013C-VE; Tue, 01 Dec 2020 07:48:29 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kk0O6-0000h8-GY; Tue, 01 Dec 2020 07:47:54 +0000 Received: from aquarius.haifa.ibm.com (nesher1.haifa.il.ibm.com [195.110.40.7]) (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 A8A74221FD; Tue, 1 Dec 2020 07:47:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1606808869; bh=DB36UnxJ8Ire65x4sAklAc3F6jMjQPYwZSaX4owToJk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=k6EYvST4MyqQ+jPrlI11XcH1hVcQ0LPHCPAS0QZ8HGXc4P1idIaV1Uqm7YMF99fds MXBrK2ZUNpCmmR+lOB4IcIbKPAyMOU/RN59fkxHV0U8K1sCSZC2QTCNwu2OzrqmoR8 QUvsQhBDYIHzTcM9PzD0UNIMnDf3LO/TS4jrxIzE= From: Mike Rapoport To: Andrew Morton Subject: [PATCH v13 08/10] PM: hibernate: disable when there are active secretmem users Date: Tue, 1 Dec 2020 09:45:57 +0200 Message-Id: <20201201074559.27742-9-rppt@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201201074559.27742-1-rppt@kernel.org> References: <20201201074559.27742-1-rppt@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201201_024751_036571_6AE7AE32 X-CRM114-Status: GOOD ( 19.74 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , David Hildenbrand , Peter Zijlstra , Catalin Marinas , Dave Hansen , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, "H. Peter Anvin" , Christopher Lameter , Shuah Khan , Thomas Gleixner , Elena Reshetova , linux-arch@vger.kernel.org, Tycho Andersen , linux-nvdimm@lists.01.org, Will Deacon , x86@kernel.org, Matthew Wilcox , Mike Rapoport , Ingo Molnar , Michael Kerrisk , Arnd Bergmann , James Bottomley , Borislav Petkov , Alexander Viro , Andy Lutomirski , Paul Walmsley , "Kirill A. Shutemov" , Dan Williams , linux-arm-kernel@lists.infradead.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Palmer Dabbelt , linux-fsdevel@vger.kernel.org, Shakeel Butt , Rick Edgecombe , Roman Gushchin , Mike Rapoport Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Mike Rapoport It is unsafe to allow saving of secretmem areas to the hibernation snapshot as they would be visible after the resume and this essentially will defeat the purpose of secret memory mappings. Prevent hibernation whenever there are active secret memory users. Signed-off-by: Mike Rapoport --- include/linux/secretmem.h | 6 ++++++ kernel/power/hibernate.c | 5 ++++- mm/secretmem.c | 15 +++++++++++++++ 3 files changed, 25 insertions(+), 1 deletion(-) diff --git a/include/linux/secretmem.h b/include/linux/secretmem.h index 70e7db9f94fe..907a6734059c 100644 --- a/include/linux/secretmem.h +++ b/include/linux/secretmem.h @@ -6,6 +6,7 @@ bool vma_is_secretmem(struct vm_area_struct *vma); bool page_is_secretmem(struct page *page); +bool secretmem_active(void); #else @@ -19,6 +20,11 @@ static inline bool page_is_secretmem(struct page *page) return false; } +static inline bool secretmem_active(void) +{ + return false; +} + #endif /* CONFIG_SECRETMEM */ #endif /* _LINUX_SECRETMEM_H */ diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index da0b41914177..559acef3fddb 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include "power.h" @@ -81,7 +82,9 @@ void hibernate_release(void) bool hibernation_available(void) { - return nohibernate == 0 && !security_locked_down(LOCKDOWN_HIBERNATION); + return nohibernate == 0 && + !security_locked_down(LOCKDOWN_HIBERNATION) && + !secretmem_active(); } /** diff --git a/mm/secretmem.c b/mm/secretmem.c index 5e3e5102ad4c..2cf5cc79418b 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -45,6 +45,13 @@ struct secretmem_ctx { static struct cma *secretmem_cma; +static atomic_t secretmem_users; + +bool secretmem_active(void) +{ + return !!atomic_read(&secretmem_users); +} + static int secretmem_account_pages(struct page *page, gfp_t gfp, int order) { int err; @@ -179,6 +186,12 @@ static const struct vm_operations_struct secretmem_vm_ops = { .fault = secretmem_fault, }; +static int secretmem_release(struct inode *inode, struct file *file) +{ + atomic_dec(&secretmem_users); + return 0; +} + static int secretmem_mmap(struct file *file, struct vm_area_struct *vma) { unsigned long len = vma->vm_end - vma->vm_start; @@ -201,6 +214,7 @@ bool vma_is_secretmem(struct vm_area_struct *vma) } static const struct file_operations secretmem_fops = { + .release = secretmem_release, .mmap = secretmem_mmap, }; @@ -318,6 +332,7 @@ SYSCALL_DEFINE1(memfd_secret, unsigned long, flags) file->f_flags |= O_LARGEFILE; fd_install(fd, file); + atomic_inc(&secretmem_users); return fd; err_put_fd: