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=-17.0 required=3.0 tests=BAYES_00,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 905AFC64E7B for ; Thu, 3 Dec 2020 06:31:37 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1748F20C56 for ; Thu, 3 Dec 2020 06:31:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1748F20C56 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 9AA7B6B0070; Thu, 3 Dec 2020 01:31:36 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 959D66B007B; Thu, 3 Dec 2020 01:31:36 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 848166B007D; Thu, 3 Dec 2020 01:31:36 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0009.hostedemail.com [216.40.44.9]) by kanga.kvack.org (Postfix) with ESMTP id 6B42E6B0070 for ; Thu, 3 Dec 2020 01:31:36 -0500 (EST) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 2F43C180AD80F for ; Thu, 3 Dec 2020 06:31:36 +0000 (UTC) X-FDA: 77550999792.24.oil08_48143f2273b9 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin24.hostedemail.com (Postfix) with ESMTP id 0913F1A4A0 for ; Thu, 3 Dec 2020 06:31:36 +0000 (UTC) X-HE-Tag: oil08_48143f2273b9 X-Filterd-Recvd-Size: 5175 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf06.hostedemail.com (Postfix) with ESMTP for ; Thu, 3 Dec 2020 06:31:35 +0000 (UTC) From: Mike Rapoport Authentication-Results:mail.kernel.org; dkim=permerror (bad message/signature format) To: Andrew Morton Cc: Alexander Viro , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Christopher Lameter , Dan Williams , Dave Hansen , David Hildenbrand , Elena Reshetova , "H. Peter Anvin" , Ingo Molnar , James Bottomley , "Kirill A. Shutemov" , Matthew Wilcox , Mark Rutland , Mike Rapoport , Mike Rapoport , Michael Kerrisk , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Rick Edgecombe , Roman Gushchin , Shakeel Butt , Shuah Khan , Thomas Gleixner , Tycho Andersen , Will Deacon , linux-api@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-nvdimm@lists.01.org, linux-riscv@lists.infradead.org, x86@kernel.org Subject: [PATCH v14 08/10] PM: hibernate: disable when there are active secretmem users Date: Thu, 3 Dec 2020 08:29:47 +0200 Message-Id: <20201203062949.5484-9-rppt@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201203062949.5484-1-rppt@kernel.org> References: <20201203062949.5484-1-rppt@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Mike Rapoport It is unsafe to allow saving of secretmem areas to the hibernation snapsh= ot as they would be visible after the resume and this essentially will defea= t 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 @@ =20 bool vma_is_secretmem(struct vm_area_struct *vma); bool page_is_secretmem(struct page *page); +bool secretmem_active(void); =20 #else =20 @@ -19,6 +20,11 @@ static inline bool page_is_secretmem(struct page *page= ) return false; } =20 +static inline bool secretmem_active(void) +{ + return false; +} + #endif /* CONFIG_SECRETMEM */ =20 #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 =20 #include "power.h" @@ -81,7 +82,9 @@ void hibernate_release(void) =20 bool hibernation_available(void) { - return nohibernate =3D=3D 0 && !security_locked_down(LOCKDOWN_HIBERNATI= ON); + return nohibernate =3D=3D 0 && + !security_locked_down(LOCKDOWN_HIBERNATION) && + !secretmem_active(); } =20 /** diff --git a/mm/secretmem.c b/mm/secretmem.c index 2390901d3ff7..7236f4d9458a 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -45,6 +45,13 @@ struct secretmem_ctx { =20 static struct cma *secretmem_cma; =20 +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 ord= er) { int err; @@ -179,6 +186,12 @@ static const struct vm_operations_struct secretmem_v= m_ops =3D { .fault =3D secretmem_fault, }; =20 +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 =3D vma->vm_end - vma->vm_start; @@ -201,6 +214,7 @@ bool vma_is_secretmem(struct vm_area_struct *vma) } =20 static const struct file_operations secretmem_fops =3D { + .release =3D secretmem_release, .mmap =3D secretmem_mmap, }; =20 @@ -318,6 +332,7 @@ SYSCALL_DEFINE1(memfd_secret, unsigned long, flags) file->f_flags |=3D O_LARGEFILE; =20 fd_install(fd, file); + atomic_inc(&secretmem_users); return fd; =20 err_put_fd: --=20 2.28.0