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=-12.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 46B67C63777 for ; Tue, 10 Nov 2020 15:16:15 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C254020781 for ; Tue, 10 Nov 2020 15:16:14 +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="I1REZJg8" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C254020781 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 3F3A76B0073; Tue, 10 Nov 2020 10:16:14 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 3A2206B0074; Tue, 10 Nov 2020 10:16:14 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 244A76B0083; Tue, 10 Nov 2020 10:16:14 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0116.hostedemail.com [216.40.44.116]) by kanga.kvack.org (Postfix) with ESMTP id ED1786B0073 for ; Tue, 10 Nov 2020 10:16:13 -0500 (EST) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 89F0B1EF1 for ; Tue, 10 Nov 2020 15:16:13 +0000 (UTC) X-FDA: 77468859426.26.wrist35_4a17329272f6 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin26.hostedemail.com (Postfix) with ESMTP id 0D7BC1804B65A for ; Tue, 10 Nov 2020 15:16:13 +0000 (UTC) X-HE-Tag: wrist35_4a17329272f6 X-Filterd-Recvd-Size: 5764 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf38.hostedemail.com (Postfix) with ESMTP for ; Tue, 10 Nov 2020 15:16:12 +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 D52AB20867; Tue, 10 Nov 2020 15:16:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605021371; bh=bXQ08oQbJjd64ut71kAPSnjbNPgwVGbPO0b8KG4J3uk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=I1REZJg8//jlAajYS7NrNWWqDzVBeT/zb1yzfhsjMV8XBYJ4XZG1kobIrZNjmAtqA ZxzK+caYHkU0QpXnJ1KGInxClCr5BksMdF76jlpq1kaX/tOrFgCs/7yYwcGdSG9cto EKF+M7jXrwqR+n8RYFsiJP66iH4G7si+wpPQCu80= 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 , 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 v8 7/9] PM: hibernate: disable when there are active secretmem users Date: Tue, 10 Nov 2020 17:14:42 +0200 Message-Id: <20201110151444.20662-8-rppt@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201110151444.20662-1-rppt@kernel.org> References: <20201110151444.20662-1-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 | 16 ++++++++++++++++ 3 files changed, 26 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 1eb7667016fa..5ed6b2070136 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -50,6 +50,13 @@ 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_memcg_charge(struct page *page, gfp_t gfp, int orde= r) { unsigned long nr_pages =3D (1 << order); @@ -189,6 +196,12 @@ 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) { struct secretmem_ctx *ctx =3D file->private_data; @@ -214,7 +227,9 @@ bool vma_is_secretmem(struct vm_area_struct *vma) return vma->vm_ops =3D=3D &secretmem_vm_ops; } =20 + const struct file_operations secretmem_fops =3D { + .release =3D secretmem_release, .mmap =3D secretmem_mmap, }; =20 @@ -332,6 +347,7 @@ 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