From patchwork Mon Feb 3 10:28:06 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 13957220 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B31FBC02196 for ; Mon, 3 Feb 2025 10:28:57 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 86BB3280002; Mon, 3 Feb 2025 05:28:56 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 81B5028000E; Mon, 3 Feb 2025 05:28:56 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6BC79280002; Mon, 3 Feb 2025 05:28:56 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 31D0028000E for ; Mon, 3 Feb 2025 05:28:56 -0500 (EST) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id EAE4D4CDFE for ; Mon, 3 Feb 2025 10:28:49 +0000 (UTC) X-FDA: 83078259978.02.39E536F Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf06.hostedemail.com (Postfix) with ESMTP id 5EA1F180003 for ; Mon, 3 Feb 2025 10:28:48 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf06.hostedemail.com: domain of kevin.brodsky@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=kevin.brodsky@arm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1738578528; a=rsa-sha256; cv=none; b=3LsHkL+DOEY15lQRCU2BrKljuN/rBr2plo/7nIsJnKVEu81+x61iUMXZwOl/V+MQLFzc0X K1rF/dZvTfeKGVigdQG26CH2y7QWqjByeQRThSh5JECEiTpugy0av786utZkdmj1skh7J3 J8LSzc2hHcyqten7ah+QrqA1tK2C6gA= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf06.hostedemail.com: domain of kevin.brodsky@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=kevin.brodsky@arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1738578528; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=tqpNjfnw7iMi+gWoBv0avsygAJN2y4ykdULl/ADYxb8=; b=mxfbNfmpkDs6tySXA5c0ww+VxCIo8w3TIINuTIs7JiLtVwIIuVTqTaEIFAB9c7Er38kMVA VssDGQ2AGkQvR7wOfc1U4j3SkdZEVt0ad6fPHSgPIt/vW/Ps+27m1VFXXZU3VpcvNHgUpQ jC8iQAc4w+iuBFK7onW9r1hFmSoQE7k= Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 23BF31BB0; Mon, 3 Feb 2025 02:29:12 -0800 (PST) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E99793F63F; Mon, 3 Feb 2025 02:28:43 -0800 (PST) From: Kevin Brodsky To: linux-hardening@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Andrew Morton , Mark Brown , Catalin Marinas , Dave Hansen , David Howells , "Eric W. Biederman" , Jann Horn , Jeff Xu , Joey Gouly , Kees Cook , Linus Walleij , Andy Lutomirski , Marc Zyngier , Peter Zijlstra , Pierre Langlois , Quentin Perret , "Mike Rapoport (IBM)" , Ryan Roberts , Thomas Gleixner , Will Deacon , Matthew Wilcox , Qi Zheng , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, x86@kernel.org Subject: [RFC PATCH 5/8] mm: kpkeys: Introduce cred pkey/level Date: Mon, 3 Feb 2025 10:28:06 +0000 Message-ID: <20250203102809.1223255-6-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250203102809.1223255-1-kevin.brodsky@arm.com> References: <20250203102809.1223255-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 5EA1F180003 X-Stat-Signature: smmx4yu8bcukaacmcsf8drxxjmp64ec3 X-Rspam-User: X-HE-Tag: 1738578528-135936 X-HE-Meta: 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 TScOcpDk c11RR6+G5cZMEwOLIRceBI88mIafg8S4dw/2MQ4LUym0PzAPOznMDNphRALc9eC0kLSZ2bIiFtOMPARAEKk+dPqPd8zoepRB5N4xtprAr9bTgbPh67sgCOyvhjgX3Cp+EuNaOohYgX0MocUMmzEhPPTnQ8Q== 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: List-Subscribe: List-Unsubscribe: We will need a separate pkey to protect struct cred. Allocate one as well as a new kpkeys level that grants write access to that pkey, and add a guard that switches to that level. Signed-off-by: Kevin Brodsky --- arch/arm64/include/asm/kpkeys.h | 4 ++++ include/asm-generic/kpkeys.h | 4 ++++ include/linux/kpkeys.h | 9 ++++++++- 3 files changed, 16 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/kpkeys.h b/arch/arm64/include/asm/kpkeys.h index ab2305ca24b7..f5797e579fb9 100644 --- a/arch/arm64/include/asm/kpkeys.h +++ b/arch/arm64/include/asm/kpkeys.h @@ -22,6 +22,10 @@ static inline u64 por_set_kpkeys_level(u64 por, int level) level == KPKEYS_LVL_PGTABLES || level == KPKEYS_LVL_UNRESTRICTED ? POE_RW : POE_R); + por = por_set_pkey_perms(por, KPKEYS_PKEY_CRED, + level == KPKEYS_LVL_CRED || + level == KPKEYS_LVL_UNRESTRICTED + ? POE_RW : POE_R); return por; } diff --git a/include/asm-generic/kpkeys.h b/include/asm-generic/kpkeys.h index cec92334a9f3..56a2fc9fe4a6 100644 --- a/include/asm-generic/kpkeys.h +++ b/include/asm-generic/kpkeys.h @@ -2,6 +2,10 @@ #ifndef __ASM_GENERIC_KPKEYS_H #define __ASM_GENERIC_KPKEYS_H +#ifndef KPKEYS_PKEY_CRED +#define KPKEYS_PKEY_CRED 2 +#endif + #ifndef KPKEYS_PKEY_PGTABLES #define KPKEYS_PKEY_PGTABLES 1 #endif diff --git a/include/linux/kpkeys.h b/include/linux/kpkeys.h index c5d804c1ab7b..a478eaf2e14f 100644 --- a/include/linux/kpkeys.h +++ b/include/linux/kpkeys.h @@ -10,7 +10,8 @@ struct folio; #define KPKEYS_LVL_DEFAULT 0 #define KPKEYS_LVL_PGTABLES 1 -#define KPKEYS_LVL_UNRESTRICTED 2 +#define KPKEYS_LVL_CRED 2 +#define KPKEYS_LVL_UNRESTRICTED 3 #define KPKEYS_LVL_MIN KPKEYS_LVL_DEFAULT #define KPKEYS_LVL_MAX KPKEYS_LVL_UNRESTRICTED @@ -160,4 +161,10 @@ KPKEYS_GUARD(kpkeys_rcu, KPKEYS_LVL_UNRESTRICTED) KPKEYS_GUARD_NOOP(kpkeys_rcu) #endif +#ifdef CONFIG_KPKEYS_HARDENED_CRED +KPKEYS_GUARD(kpkeys_hardened_cred, KPKEYS_LVL_CRED) +#else +KPKEYS_GUARD_NOOP(kpkeys_hardened_cred) +#endif + #endif /* _LINUX_KPKEYS_H */