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=-16.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 A58E6C63777 for ; Wed, 25 Nov 2020 09:23:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1D6C4221F7 for ; Wed, 25 Nov 2020 09:23:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Zeh6J+Eg" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1D6C4221F7 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 926586B0072; Wed, 25 Nov 2020 04:23:52 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 8AE2B6B007B; Wed, 25 Nov 2020 04:23:52 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 776F06B007D; Wed, 25 Nov 2020 04:23:52 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0202.hostedemail.com [216.40.44.202]) by kanga.kvack.org (Postfix) with ESMTP id 5A7C76B0072 for ; Wed, 25 Nov 2020 04:23:52 -0500 (EST) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 1DE4C181AEF1E for ; Wed, 25 Nov 2020 09:23:52 +0000 (UTC) X-FDA: 77522403504.02.boat87_3a0a04e27375 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin02.hostedemail.com (Postfix) with ESMTP id F216C10097AA2 for ; Wed, 25 Nov 2020 09:23:51 +0000 (UTC) X-HE-Tag: boat87_3a0a04e27375 X-Filterd-Recvd-Size: 5730 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf21.hostedemail.com (Postfix) with ESMTP for ; Wed, 25 Nov 2020 09:23:51 +0000 (UTC) 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 F33A620DD4; Wed, 25 Nov 2020 09:23:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1606296230; bh=oK2vSnvwolpB4EwUp+axAj4CN8XhshH61yb4ioPdlAY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Zeh6J+EgK6Gbu9H3RBJ2ilRnGyVw13HrQRlNuHZojMpK56eW39Ilkplpeqb+yj/DD lmRnqSPwZssx8W1MLv953IMqFAFcVFqR0sSTy1goCbTgHQxVWE6y/a//n3JwITDwQG zi3LMjWO9yNOKuJLapiWuXVam75HWFNzYjFc8Hmw= From: Mike Rapoport 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 , 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 v12 08/10] PM: hibernate: disable when there are active secretmem users Date: Wed, 25 Nov 2020 11:22:06 +0200 Message-Id: <20201125092208.12544-9-rppt@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201125092208.12544-1-rppt@kernel.org> References: <20201125092208.12544-1-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 eb6628390444..f7398eb810c5 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