From patchwork Fri Dec 7 18:39:29 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kristina Martsenko X-Patchwork-Id: 10718719 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D635417DB for ; Fri, 7 Dec 2018 18:43:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C1D562F575 for ; Fri, 7 Dec 2018 18:43:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B5ED02F578; Fri, 7 Dec 2018 18:43:30 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 2BF9B2F575 for ; Fri, 7 Dec 2018 18:43:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: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=zAq6sKQngiyfDDSHCRBhjjw7Xb6W4SbJtOBoZJHCwdA=; b=ZxryZHD4SZYbUBqe1w0fMuqPx8 drcdj/1+LcuMOZWcXv8E5CpC/sXZonzdjXvoseOOq4D4zbRU+1ZLYdI6VeBAS2/KCxMX/ibjpn8d0 aQmfwy9Jb1iGysdLcjTyyYcJF/uzbJNAyf4Xi1/7C4D+bK/vrdejJxJcqxAmTZNfwYQA4OijX2AYp 9gjqPf+OlrEXm4qFJ0sjtZ0PfJdg+8asBkQBegYjWw4AqQ/C5VQndMYb5AbihRbAJLtNhBsf6pS8d x82p2JiZEk64uyI/TYN+3tdEZhsUpd6rdy+XeZFy6gfbWqf8ZyRwhg8tQ+jVkfsIW+SQGHR2ej4Rn g2mhAUmA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gVL5p-0007pB-JT; Fri, 07 Dec 2018 18:43:17 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gVL3S-0005Da-Gw for linux-arm-kernel@lists.infradead.org; Fri, 07 Dec 2018 18:41:03 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0330BEBD; Fri, 7 Dec 2018 10:40:44 -0800 (PST) Received: from moonbear.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DE3FD3F5AF; Fri, 7 Dec 2018 10:40:40 -0800 (PST) From: Kristina Martsenko To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v6 11/13] arm64: add ptrace regsets for ptrauth key management Date: Fri, 7 Dec 2018 18:39:29 +0000 Message-Id: <20181207183931.4285-12-kristina.martsenko@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20181207183931.4285-1-kristina.martsenko@arm.com> References: <20181207183931.4285-1-kristina.martsenko@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181207_104050_699923_DD106499 X-CRM114-Status: GOOD ( 16.13 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Andrew Jones , Jacob Bramley , Ard Biesheuvel , Marc Zyngier , Catalin Marinas , Adam Wallis , Suzuki K Poulose , Richard Henderson , Christoffer Dall , Will Deacon , kvmarm@lists.cs.columbia.edu, Cyrill Gorcunov , Ramana Radhakrishnan , Amit Kachhap , Dave P Martin , linux-kernel@vger.kernel.org, Kees Cook MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Add two new ptrace regsets, which can be used to request and change the pointer authentication keys of a thread. NT_ARM_PACA_KEYS gives access to the instruction/data address keys, and NT_ARM_PACG_KEYS to the generic authentication key. The regsets are only exposed if the kernel is compiled with CONFIG_CHECKPOINT_RESTORE=y, as the intended use case is checkpointing and restoring processes that are using pointer authentication. Normally applications or debuggers should not need to know the keys (and exposing the keys is a security risk), so the regsets are not exposed by default. Signed-off-by: Kristina Martsenko --- arch/arm64/include/uapi/asm/ptrace.h | 18 +++++++++ arch/arm64/kernel/ptrace.c | 72 ++++++++++++++++++++++++++++++++++++ include/uapi/linux/elf.h | 2 + 3 files changed, 92 insertions(+) diff --git a/arch/arm64/include/uapi/asm/ptrace.h b/arch/arm64/include/uapi/asm/ptrace.h index c2f249bcd829..fafa7f6decf9 100644 --- a/arch/arm64/include/uapi/asm/ptrace.h +++ b/arch/arm64/include/uapi/asm/ptrace.h @@ -236,6 +236,24 @@ struct user_pac_mask { __u64 insn_mask; }; +/* pointer authentication keys (NT_ARM_PACA_KEYS, NT_ARM_PACG_KEYS) */ + +struct user_pac_address_keys { + __u64 apiakey_lo; + __u64 apiakey_hi; + __u64 apibkey_lo; + __u64 apibkey_hi; + __u64 apdakey_lo; + __u64 apdakey_hi; + __u64 apdbkey_lo; + __u64 apdbkey_hi; +}; + +struct user_pac_generic_keys { + __u64 apgakey_lo; + __u64 apgakey_hi; +}; + #endif /* __ASSEMBLY__ */ #endif /* _UAPI__ASM_PTRACE_H */ diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 6c1f63cb6c4e..f18f14c64d1e 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -979,6 +979,56 @@ static int pac_mask_get(struct task_struct *target, return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &uregs, 0, -1); } + +#ifdef CONFIG_CHECKPOINT_RESTORE +static int pac_address_keys_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + if (!system_supports_address_auth()) + return -EINVAL; + + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread_info.keys_user, 0, -1); +} + +static int pac_address_keys_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + if (!system_supports_address_auth()) + return -EINVAL; + + return user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &target->thread_info.keys_user, 0, -1); +} + +static int pac_generic_keys_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + if (!system_supports_generic_auth()) + return -EINVAL; + + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &target->thread_info.keys_user.apga, 0, -1); +} + +static int pac_generic_keys_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + if (!system_supports_generic_auth()) + return -EINVAL; + + return user_regset_copyin(&pos, &count, &kbuf, &ubuf, + &target->thread_info.keys_user.apga, 0, -1); +} +#endif /* CONFIG_CHECKPOINT_RESTORE */ #endif /* CONFIG_ARM64_PTR_AUTH */ enum aarch64_regset { @@ -995,6 +1045,10 @@ enum aarch64_regset { #endif #ifdef CONFIG_ARM64_PTR_AUTH REGSET_PAC_MASK, +#ifdef CONFIG_CHECKPOINT_RESTORE + REGSET_PACA_KEYS, + REGSET_PACG_KEYS, +#endif #endif }; @@ -1074,6 +1128,24 @@ static const struct user_regset aarch64_regsets[] = { .get = pac_mask_get, /* this cannot be set dynamically */ }, +#ifdef CONFIG_CHECKPOINT_RESTORE + [REGSET_PACA_KEYS] = { + .core_note_type = NT_ARM_PACA_KEYS, + .n = sizeof(struct user_pac_address_keys) / sizeof(u64), + .size = sizeof(u64), + .align = sizeof(u64), + .get = pac_address_keys_get, + .set = pac_address_keys_set, + }, + [REGSET_PACG_KEYS] = { + .core_note_type = NT_ARM_PACG_KEYS, + .n = sizeof(struct user_pac_generic_keys) / sizeof(u64), + .size = sizeof(u64), + .align = sizeof(u64), + .get = pac_generic_keys_get, + .set = pac_generic_keys_set, + }, +#endif #endif }; diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h index 3f23273d690c..c1afbc592531 100644 --- a/include/uapi/linux/elf.h +++ b/include/uapi/linux/elf.h @@ -421,6 +421,8 @@ typedef struct elf64_shdr { #define NT_ARM_SYSTEM_CALL 0x404 /* ARM system call number */ #define NT_ARM_SVE 0x405 /* ARM Scalable Vector Extension registers */ #define NT_ARM_PAC_MASK 0x406 /* ARM pointer authentication code masks */ +#define NT_ARM_PACA_KEYS 0x407 /* ARM pointer authentication address keys */ +#define NT_ARM_PACG_KEYS 0x408 /* ARM pointer authentication generic key */ #define NT_ARC_V2 0x600 /* ARCv2 accumulator/extra registers */ #define NT_VMCOREDD 0x700 /* Vmcore Device Dump Note */ #define NT_MIPS_DSP 0x800 /* MIPS DSP ASE registers */