From patchwork Fri May 19 01:19:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Xu X-Patchwork-Id: 13247590 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E8EDBC7EE30 for ; Fri, 19 May 2023 01:19:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229969AbjESBTc (ORCPT ); Thu, 18 May 2023 21:19:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230240AbjESBTa (ORCPT ); Thu, 18 May 2023 21:19:30 -0400 Received: from mail-pf1-x432.google.com (mail-pf1-x432.google.com [IPv6:2607:f8b0:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3D9B010C9 for ; Thu, 18 May 2023 18:19:28 -0700 (PDT) Received: by mail-pf1-x432.google.com with SMTP id d2e1a72fcca58-64d1e96c082so939550b3a.1 for ; Thu, 18 May 2023 18:19:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1684459168; x=1687051168; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=amUmjeQdjogZim3KCvDHtpibL1Mlx7r/unbXJ7VLzz4=; b=GibbkWqfiwuo0GDKTjKpCXZxRAC34F6flBcYc63YtvRDvtZ56HZtHKuhrJYSdwe3/+ 6kPjFdVzSbPq+cF3lXOpkjZLCMYa7ei/z4zXxpzej0So1g37PcWmqewUZUgxYJCMM+RN jmAWbhNUMedM1L5m+UzN6elDn6LRlSsQzlPeM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684459168; x=1687051168; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=amUmjeQdjogZim3KCvDHtpibL1Mlx7r/unbXJ7VLzz4=; b=aW8lOGmUXzApiLQvDxMMVDRUrSQWN1lZTgdd6SwD5z65vKXDBpxR0WMsKW/KKglexM vCLzW8rhjvP28Md4VRGreFtMzsAla1/KZP38jhZ5TnYJGWPPUA2M35mXn/RhuknHE2u9 ksCJvm6Y8uRjfkHayermSAIXu5myhmtqqF39VD2hLYPo01tmlTv2/jk+Tbd4GdM1Rg9s liXIbFi/14AP8mGkmQezlV9lh4oPETgwNGKoLn1+bmBxXMXJ4fOd2zOxh/iiWmkbq9nb Yc4x1vS73HiX+3tYCQyG4BwBeEEyYYR710MUQlYFabSPd3D7xicz7AQ8cwaJXP5YK6Pa T6ag== X-Gm-Message-State: AC+VfDyJhOtHCBi6TVfqIosWx89aWhyJsCKQ+YkHDB2mb4hE/4aEQPRt 8cAw6cXnUDTDsoqpAkNrLD13Ew== X-Google-Smtp-Source: ACHHUZ6CRfRqSBxkPWsay/WrlVhskzJPviRUVesausHDoJ1nxVzNabu1OJDVAOucE5hVphusdAmIbw== X-Received: by 2002:a05:6a00:134c:b0:648:64fe:b14b with SMTP id k12-20020a056a00134c00b0064864feb14bmr881854pfu.32.1684459167669; Thu, 18 May 2023 18:19:27 -0700 (PDT) Received: from localhost (183.43.230.35.bc.googleusercontent.com. [35.230.43.183]) by smtp.gmail.com with UTF8SMTPSA id b6-20020a630c06000000b00502ecb91940sm1824283pgl.55.2023.05.18.18.19.26 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 18 May 2023 18:19:27 -0700 (PDT) From: jeffxu@chromium.org To: dave.hansen@intel.com, luto@kernel.org, jorgelo@chromium.org, keescook@chromium.org, groeck@chromium.org, jannh@google.com, sroettger@google.com Cc: akpm@linux-foundation.org, jeffxu@google.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-hardening@vger.kernel.org Subject: [PATCH v1 1/6] PKEY: Introduce PKEY_ENFORCE_API flag Date: Fri, 19 May 2023 01:19:09 +0000 Message-ID: <20230519011915.846407-2-jeffxu@chromium.org> X-Mailer: git-send-email 2.40.1.698.g37aff9b760-goog In-Reply-To: <20230519011915.846407-1-jeffxu@chromium.org> References: <20230519011915.846407-1-jeffxu@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org From: Jeff Xu This patch introduces a new flag, PKEY_ENFORCE_API, to the pkey_alloc() function. When a PKEY is created with this flag, it is enforced that any thread that wants to make changes to the memory mapping (such as mprotect/munmap) of the memory must have write access to the PKEY. This is to prevent unauthorized access to protected memory. PKEYs created without this flag will continue to work as they do now, for backwards compatibility. Signed-off-by: Jeff Xu --- arch/powerpc/include/asm/pkeys.h | 11 ++++++++- arch/x86/include/asm/mmu.h | 7 ++++++ arch/x86/include/asm/pkeys.h | 42 ++++++++++++++++++++++++++++++-- arch/x86/mm/pkeys.c | 2 +- include/linux/pkeys.h | 9 ++++++- include/uapi/linux/mman.h | 5 ++++ mm/mprotect.c | 6 ++--- 7 files changed, 74 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h index 59a2c7dbc78f..943333ac0fee 100644 --- a/arch/powerpc/include/asm/pkeys.h +++ b/arch/powerpc/include/asm/pkeys.h @@ -82,7 +82,7 @@ static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey) * Relies on the mmap_lock to protect against concurrency in mm_pkey_alloc() and * mm_pkey_free(). */ -static inline int mm_pkey_alloc(struct mm_struct *mm) +static inline int mm_pkey_alloc(struct mm_struct *mm, unsigned long flags) { /* * Note: this is the one and only place we make sure that the pkey is @@ -168,5 +168,14 @@ static inline bool arch_pkeys_enabled(void) return mmu_has_feature(MMU_FTR_PKEY); } +static inline bool arch_check_pkey_alloc_flags(unsigned long flags) +{ + /* No flags supported yet. */ + if (flags) + return false; + + return true; +} + extern void pkey_mm_init(struct mm_struct *mm); #endif /*_ASM_POWERPC_KEYS_H */ diff --git a/arch/x86/include/asm/mmu.h b/arch/x86/include/asm/mmu.h index 0da5c227f490..d97594b44d9a 100644 --- a/arch/x86/include/asm/mmu.h +++ b/arch/x86/include/asm/mmu.h @@ -66,6 +66,13 @@ typedef struct { */ u16 pkey_allocation_map; s16 execute_only_pkey; + /* + * One bit per protection key. + * When set, thread must have write permission on corresponding + * PKRU in order to call memory mapping API, such as mprotect, + * munmap, etc. + */ + u16 pkey_enforce_api_map; #endif } mm_context_t; diff --git a/arch/x86/include/asm/pkeys.h b/arch/x86/include/asm/pkeys.h index 2e6c04d8a45b..ecadf04a8251 100644 --- a/arch/x86/include/asm/pkeys.h +++ b/arch/x86/include/asm/pkeys.h @@ -51,6 +51,17 @@ static inline int arch_override_mprotect_pkey(struct vm_area_struct *vma, mm_pkey_allocation_map(mm) &= ~(1U << pkey); \ } while (0) +#define mm_pkey_enforce_api_map(mm) (mm->context.pkey_enforce_api_map) +#define mm_set_pkey_enforce_api(mm, pkey) \ + { \ + mm_pkey_enforce_api_map(mm) |= (1U << pkey); \ + } + +#define mm_clear_pkey_enforce_api(mm, pkey) \ + { \ + mm_pkey_enforce_api_map(mm) &= ~(1U << pkey); \ + } + static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey) { @@ -74,11 +85,25 @@ bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey) return mm_pkey_allocation_map(mm) & (1U << pkey); } +/* + * Return true if the pkey has ENFORCE_API flag during allocation. + */ +static inline bool mm_pkey_enforce_api(struct mm_struct *mm, int pkey) +{ + /* + * Only pkey created by user space has the flag. + * execute_only_pkey check is in mm_pkey_is_allocated(). + */ + if (pkey != ARCH_DEFAULT_PKEY && mm_pkey_is_allocated(mm, pkey)) + return mm_pkey_enforce_api_map(mm) & (1U << pkey); + + return false; +} + /* * Returns a positive, 4-bit key on success, or -1 on failure. */ -static inline -int mm_pkey_alloc(struct mm_struct *mm) +static inline int mm_pkey_alloc(struct mm_struct *mm, unsigned long flags) { /* * Note: this is the one and only place we make sure @@ -101,6 +126,9 @@ int mm_pkey_alloc(struct mm_struct *mm) mm_set_pkey_allocated(mm, ret); + if (flags & PKEY_ENFORCE_API) + mm_set_pkey_enforce_api(mm, ret); + return ret; } @@ -110,6 +138,7 @@ int mm_pkey_free(struct mm_struct *mm, int pkey) if (!mm_pkey_is_allocated(mm, pkey)) return -EINVAL; + mm_clear_pkey_enforce_api(mm, pkey); mm_set_pkey_free(mm, pkey); return 0; @@ -123,4 +152,13 @@ static inline int vma_pkey(struct vm_area_struct *vma) return (vma->vm_flags & vma_pkey_mask) >> VM_PKEY_SHIFT; } +static inline bool arch_check_pkey_alloc_flags(unsigned long flags) +{ + unsigned long valid_flags = PKEY_ENFORCE_API; + + if (flags & ~valid_flags) + return false; + + return true; +} #endif /*_ASM_X86_PKEYS_H */ diff --git a/arch/x86/mm/pkeys.c b/arch/x86/mm/pkeys.c index 7418c367e328..a76981f44acf 100644 --- a/arch/x86/mm/pkeys.c +++ b/arch/x86/mm/pkeys.c @@ -20,7 +20,7 @@ int __execute_only_pkey(struct mm_struct *mm) /* Do we need to assign a pkey for mm's execute-only maps? */ if (execute_only_pkey == -1) { /* Go allocate one to use, which might fail */ - execute_only_pkey = mm_pkey_alloc(mm); + execute_only_pkey = mm_pkey_alloc(mm, 0); if (execute_only_pkey < 0) return -1; need_to_set_mm_pkey = true; diff --git a/include/linux/pkeys.h b/include/linux/pkeys.h index 86be8bf27b41..81a482c3e051 100644 --- a/include/linux/pkeys.h +++ b/include/linux/pkeys.h @@ -3,6 +3,7 @@ #define _LINUX_PKEYS_H #include +#include #define ARCH_DEFAULT_PKEY 0 @@ -25,7 +26,7 @@ static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey) return (pkey == 0); } -static inline int mm_pkey_alloc(struct mm_struct *mm) +static inline int mm_pkey_alloc(struct mm_struct *mm, unsigned long flags) { return -1; } @@ -46,6 +47,12 @@ static inline bool arch_pkeys_enabled(void) return false; } +static inline bool arch_check_pkey_alloc_flags(unsigned long flags) +{ + if (flags) + return false; + return true; +} #endif /* ! CONFIG_ARCH_HAS_PKEYS */ #endif /* _LINUX_PKEYS_H */ diff --git a/include/uapi/linux/mman.h b/include/uapi/linux/mman.h index f55bc680b5b0..8c69b9a7ff5b 100644 --- a/include/uapi/linux/mman.h +++ b/include/uapi/linux/mman.h @@ -41,4 +41,9 @@ #define MAP_HUGE_2GB HUGETLB_FLAG_ENCODE_2GB #define MAP_HUGE_16GB HUGETLB_FLAG_ENCODE_16GB +/* + * Flags for pkey_alloc + */ +#define PKEY_ENFORCE_API (1 << 0) + #endif /* _UAPI_LINUX_MMAN_H */ diff --git a/mm/mprotect.c b/mm/mprotect.c index 92d3d3ca390a..8a68fdca8487 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -894,15 +894,15 @@ SYSCALL_DEFINE2(pkey_alloc, unsigned long, flags, unsigned long, init_val) int pkey; int ret; - /* No flags supported yet. */ - if (flags) + if (!arch_check_pkey_alloc_flags(flags)) return -EINVAL; + /* check for unsupported init values */ if (init_val & ~PKEY_ACCESS_MASK) return -EINVAL; mmap_write_lock(current->mm); - pkey = mm_pkey_alloc(current->mm); + pkey = mm_pkey_alloc(current->mm, flags); ret = -ENOSPC; if (pkey == -1) From patchwork Fri May 19 01:19:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Xu X-Patchwork-Id: 13247589 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BE87BC7EE2C for ; Fri, 19 May 2023 01:19:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230357AbjESBTd (ORCPT ); Thu, 18 May 2023 21:19:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53576 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230298AbjESBTb (ORCPT ); Thu, 18 May 2023 21:19:31 -0400 Received: from mail-pj1-x102f.google.com (mail-pj1-x102f.google.com [IPv6:2607:f8b0:4864:20::102f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4614B10D0 for ; Thu, 18 May 2023 18:19:29 -0700 (PDT) Received: by mail-pj1-x102f.google.com with SMTP id 98e67ed59e1d1-24e14a24c9dso2157408a91.0 for ; Thu, 18 May 2023 18:19:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1684459169; x=1687051169; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=TQS98FLuUxt8kfip9Nk8O1hVfeuWAt0sl7+06c/6tso=; b=OGPd3mn4AXIrc1RRZIu250DTtUsK1KYvi8EfuJPLZrZrm+XTM1dOslqaOYntJ4QlnF P1XUdOXQFW2q48KVb2YvQI1UOuJ6zvUuQNOwxGx4Ltcqz+zGeskAKaAjKOirPNTB39HS jBq/1Yq0YsewgO7yu5hZy+p7qvRI04QhhT2rY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684459169; x=1687051169; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=TQS98FLuUxt8kfip9Nk8O1hVfeuWAt0sl7+06c/6tso=; b=MfnZY47MOM/l9a28REzgc8a86sCmvF9H6ci4htoK2pTf2mPiq4hfvFkQYOr3C3n+DD qe8xxdJYAD2oDa+wDaYtSgrTqJMve7NnLrJ9zgbj1/6RysQxNCzngo0HvydTvHzadrsT Wy1pmnY8SJsiyqrfj6SXnPwkidUg8ygV5PSiC/9tKZB7sSIao/8wKcnwIOSdX8TXx7u5 VwL1ch5kaNspVyjI9HaCK5TeP8XI6hyODn0T31kiNcEaaVmjY88rJU0FJi6wOLLfkpMr UViNnGb4lrtg3ueffitlGoH6po/mfqtd8LuZij37U+RuzYWIwUNS8ROr6YI5i4tJ3jf7 jLYw== X-Gm-Message-State: AC+VfDyHpA0mArUFCwZK/9vIwjsUhK2smwKo6/FUsUGwXEViE1EzYtqZ s0V53sPOzjkh9EJNcEEFYMEVfQ== X-Google-Smtp-Source: ACHHUZ61pfxccHt/KzXaf0wYbWk/1Tu3oFrft5OWJaPA3VQ8PQiXauBnEJkKqfgy+TrBmMg73D6nkg== X-Received: by 2002:a17:90b:3ecc:b0:246:85ec:d816 with SMTP id rm12-20020a17090b3ecc00b0024685ecd816mr538354pjb.3.1684459168766; Thu, 18 May 2023 18:19:28 -0700 (PDT) Received: from localhost (183.43.230.35.bc.googleusercontent.com. [35.230.43.183]) by smtp.gmail.com with UTF8SMTPSA id a19-20020a17090acb9300b0025356cce0e4sm279592pju.24.2023.05.18.18.19.27 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 18 May 2023 18:19:28 -0700 (PDT) From: jeffxu@chromium.org To: dave.hansen@intel.com, luto@kernel.org, jorgelo@chromium.org, keescook@chromium.org, groeck@chromium.org, jannh@google.com, sroettger@google.com Cc: akpm@linux-foundation.org, jeffxu@google.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-hardening@vger.kernel.org Subject: [PATCH v1 2/6] PKEY: Add arch_check_pkey_enforce_api() Date: Fri, 19 May 2023 01:19:10 +0000 Message-ID: <20230519011915.846407-3-jeffxu@chromium.org> X-Mailer: git-send-email 2.40.1.698.g37aff9b760-goog In-Reply-To: <20230519011915.846407-1-jeffxu@chromium.org> References: <20230519011915.846407-1-jeffxu@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org From: Jeff Xu This patch adds an architecture-independent function, arch_check_pkey_enforce_api(), that checks whether the calling thread has write access to the PKRU for a given range of memory. If the memory range is protected by PKEY_ENFORCE_API, then the thread must have write access to the PKRU in order to make changes to the memory mapping (such as mprotect/munmap). This function is used by the kernel to enforce the PKEY_ENFORCE_API flag. Signed-off-by: Jeff Xu --- arch/powerpc/include/asm/pkeys.h | 8 +++++ arch/x86/include/asm/pkeys.h | 50 ++++++++++++++++++++++++++++++++ include/linux/pkeys.h | 9 ++++++ 3 files changed, 67 insertions(+) diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h index 943333ac0fee..24c481e5e95b 100644 --- a/arch/powerpc/include/asm/pkeys.h +++ b/arch/powerpc/include/asm/pkeys.h @@ -177,5 +177,13 @@ static inline bool arch_check_pkey_alloc_flags(unsigned long flags) return true; } +static inline int arch_check_pkey_enforce_api(struct mm_struct *mm, + unsigned long start, + unsigned long end) +{ + /* Allow by default */ + return 0; +} + extern void pkey_mm_init(struct mm_struct *mm); #endif /*_ASM_POWERPC_KEYS_H */ diff --git a/arch/x86/include/asm/pkeys.h b/arch/x86/include/asm/pkeys.h index ecadf04a8251..8b94ffc4ca32 100644 --- a/arch/x86/include/asm/pkeys.h +++ b/arch/x86/include/asm/pkeys.h @@ -161,4 +161,54 @@ static inline bool arch_check_pkey_alloc_flags(unsigned long flags) return true; } + +static inline int __arch_check_vma_pkey_for_write(struct vm_area_struct *vma) +{ + int pkey = vma_pkey(vma); + + if (mm_pkey_enforce_api(vma->vm_mm, pkey)) { + if (!__pkru_allows_write(read_pkru(), pkey)) + return -EACCES; + } + + return 0; +} + +/* + * arch_check_pkey_enforce_api is used by the kernel to enforce + * PKEY_ENFORCE_API flag. + * It checks whether the calling thread has write access to the PKRU + * for a given range of memory. If the memory range is protected by + * PKEY_ENFORCE_API, then the thread must have write access to the + * PKRU in order to make changes to the memory mapping, such as + * mprotect/munmap. + */ +static inline int arch_check_pkey_enforce_api(struct mm_struct *mm, + unsigned long start, + unsigned long end) +{ + int error; + struct vm_area_struct *vma; + + if (!arch_pkeys_enabled()) + return 0; + + while (true) { + vma = find_vma_intersection(mm, start, end); + if (!vma) + break; + + error = __arch_check_vma_pkey_for_write(vma); + if (error) + return error; + + if (vma->vm_end >= end) + break; + + start = vma->vm_end; + } + + return 0; +} + #endif /*_ASM_X86_PKEYS_H */ diff --git a/include/linux/pkeys.h b/include/linux/pkeys.h index 81a482c3e051..7b00689e1c24 100644 --- a/include/linux/pkeys.h +++ b/include/linux/pkeys.h @@ -53,6 +53,15 @@ static inline bool arch_check_pkey_alloc_flags(unsigned long flags) return false; return true; } + +static inline int arch_check_pkey_enforce_api(struct mm_struct *mm, + unsigned long start, + unsigned long end) +{ + // Allow by default. + return 0; +} + #endif /* ! CONFIG_ARCH_HAS_PKEYS */ #endif /* _LINUX_PKEYS_H */ From patchwork Fri May 19 01:19:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Xu X-Patchwork-Id: 13247588 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1EE7FC7EE32 for ; Fri, 19 May 2023 01:19:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230298AbjESBTf (ORCPT ); Thu, 18 May 2023 21:19:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53596 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230402AbjESBTb (ORCPT ); Thu, 18 May 2023 21:19:31 -0400 Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [IPv6:2607:f8b0:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39F94E4C for ; Thu, 18 May 2023 18:19:30 -0700 (PDT) Received: by mail-pf1-x434.google.com with SMTP id d2e1a72fcca58-64384c6797eso2123266b3a.2 for ; Thu, 18 May 2023 18:19:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1684459169; x=1687051169; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=DlYfhs3BTQ2EJ5c00OoF7xAAokRQfPc4lQTpfzHm9OE=; b=JWIfslA4UKDBw1Mp583btzlGGK8G9E6xpS7M8yt3iOyE0agyVlu+KO5Lxq4vpucXSU HH1YA4BQeb7OL6OLVkoix4UxlcxXNVOrDy2c5gWBw82vyYqfMb8tY9sDkBb9j+Na0b8j 0kO3Cd+a0jrUOyQcvN7J2vDvvbkTYN/CiGCqY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684459169; x=1687051169; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=DlYfhs3BTQ2EJ5c00OoF7xAAokRQfPc4lQTpfzHm9OE=; b=aPQJECkOx4lF6hs9USwZYMyo2Y3hn7JSnB/9+kbijcIo7ndb26mDfZk1RETJcu2TXw jJG6+4Ge8PEmiEgRN5eIQ4cuh4H8776V61J+ItVzw4Uql3thuSnt2M3ehGCKMC82QtX7 +Gd5g9kvpWh8ZYwm86lPkW3RUpTQ1GZ/p60hYLHbpnicS56Sm3zrkaa53/EqMK3xSZff J4jKiUcRxFEO+Sg3flPr7Ru3vtjMmKMa+RXnAj09HNdtKF0n2JVBLVb6XF891YZM/47J bxo9Fh9gJAuJdOejhb9R6NwIshx/P621ImQTr/JYaGPWHpniEpKU+tmkSDlaBEOMOVxG U5dA== X-Gm-Message-State: AC+VfDzWjznMEs0G7G5DeWXFrvVPCRMm4K5yEfUu0YoYhjUGdFCx1ty6 24GiXkoPLqGjU81csaVRCpoEcA== X-Google-Smtp-Source: ACHHUZ65BMUPG6NH0sSEE5yDD+qKd1DPXj0Iug+5r1nNE9fAXNvkKS48swgrqtg3LFDKz96p8HSxUA== X-Received: by 2002:a05:6a20:8422:b0:ef:205f:8184 with SMTP id c34-20020a056a20842200b000ef205f8184mr425525pzd.13.1684459169739; Thu, 18 May 2023 18:19:29 -0700 (PDT) Received: from localhost (183.43.230.35.bc.googleusercontent.com. [35.230.43.183]) by smtp.gmail.com with UTF8SMTPSA id c24-20020a62e818000000b00643864d03dfsm1960424pfi.171.2023.05.18.18.19.29 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 18 May 2023 18:19:29 -0700 (PDT) From: jeffxu@chromium.org To: dave.hansen@intel.com, luto@kernel.org, jorgelo@chromium.org, keescook@chromium.org, groeck@chromium.org, jannh@google.com, sroettger@google.com Cc: akpm@linux-foundation.org, jeffxu@google.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-hardening@vger.kernel.org Subject: [PATCH v1 3/6] PKEY: Apply PKEY_ENFORCE_API to mprotect Date: Fri, 19 May 2023 01:19:11 +0000 Message-ID: <20230519011915.846407-4-jeffxu@chromium.org> X-Mailer: git-send-email 2.40.1.698.g37aff9b760-goog In-Reply-To: <20230519011915.846407-1-jeffxu@chromium.org> References: <20230519011915.846407-1-jeffxu@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org From: Jeff Xu This patch enables PKEY_ENFORCE_API for the mprotect and mprotect_pkey syscalls. Signed-off-by: Jeff Xu --- mm/mprotect.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/mm/mprotect.c b/mm/mprotect.c index 8a68fdca8487..1db30b8baac3 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -794,6 +794,17 @@ static int do_mprotect_pkey(unsigned long start, size_t len, } } + /* + * arch_check_pkey_enforce_api checks if current thread + * has the PKEY permission to modify the memory mapping. + * Note: this should only apply to the cases that do_mprotect_pkey + * is called from syscall entry. Ref. to munmap for other cases. + */ + if (arch_check_pkey_enforce_api(current->mm, start, end) < 0) { + error = -EACCES; + goto out; + } + prev = vma_prev(&vmi); if (start > vma->vm_start) prev = vma; From patchwork Fri May 19 01:19:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Xu X-Patchwork-Id: 13247591 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D32EC7EE37 for ; Fri, 19 May 2023 01:19:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230517AbjESBTf (ORCPT ); Thu, 18 May 2023 21:19:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53576 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231135AbjESBTe (ORCPT ); Thu, 18 May 2023 21:19:34 -0400 Received: from mail-pg1-x531.google.com (mail-pg1-x531.google.com [IPv6:2607:f8b0:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 630D2E7F for ; Thu, 18 May 2023 18:19:31 -0700 (PDT) Received: by mail-pg1-x531.google.com with SMTP id 41be03b00d2f7-51b4ef5378bso2476930a12.1 for ; Thu, 18 May 2023 18:19:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1684459171; x=1687051171; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=qzO3EawE44DmDL2RDFGxHbI+J47AsuGzE5x/fc5YRSs=; b=Xz+5GZCb3fba+tXdlILZoYQkV4SVPHj5Vwq3DIRmzGvX64eYAzu0JkwUukNwnffs54 M9v00G5vG3JMYqhRAZSNj3NjdZf+5DSxJMHNq9AQDEWFtawgnIFbemZ5wunbbCOLlxtw ghWDWiFb7TtOseQ9yPeyC/EQ4o67LIc0xOhfo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684459171; x=1687051171; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=qzO3EawE44DmDL2RDFGxHbI+J47AsuGzE5x/fc5YRSs=; b=MrM2+/cSYPvL2i2FDIpb9ICWmFRXFzmu44923Jb++l+vkCcH9dPxcRxTGLrhCaUXF6 MB70rtRy2QHCC+YDQfvcfhqRSWoZ6PyuPkjTI6lgytmZezrBhPyU8dPXu6Pc0NoUHZqA /LheuSPj4VUkRUU95MU1tdO6w3HNYWvBGVcWw+/pXKC3hfQUAFGJlmLW9gVsZU/dtdjn uqBCewLKdic2af4l0Q4NBqv4oD9eyPWYlhVwm60k4F+xbEojuKOxf5o5ny/EGCpvuFt5 38dlOV4e58yUcLkD3n9tT2LXozbWW2Byh3GPWy+aRA5o1LWda0dIqcu1OdG5sqZjWiaF OpjA== X-Gm-Message-State: AC+VfDzD4UjeZ/0N/AEpc54/VLrztN/WfVj29nzN9vUN77SPRT1iE/A1 zhxafGVKmKcTlV3spCkXvTg1Ug== X-Google-Smtp-Source: ACHHUZ6Fs6CYowy/agA+FF47C4n9YuZUo/3YX8PaB++LosNzsroEAzIx6Gf688Y9ZcsCjvKb79F0WQ== X-Received: by 2002:a05:6a20:c18d:b0:102:7aec:6dcc with SMTP id bg13-20020a056a20c18d00b001027aec6dccmr299922pzb.27.1684459170711; Thu, 18 May 2023 18:19:30 -0700 (PDT) Received: from localhost (183.43.230.35.bc.googleusercontent.com. [35.230.43.183]) by smtp.gmail.com with UTF8SMTPSA id f62-20020a17090a704400b0023d386e4806sm294372pjk.57.2023.05.18.18.19.30 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 18 May 2023 18:19:30 -0700 (PDT) From: jeffxu@chromium.org To: dave.hansen@intel.com, luto@kernel.org, jorgelo@chromium.org, keescook@chromium.org, groeck@chromium.org, jannh@google.com, sroettger@google.com Cc: akpm@linux-foundation.org, jeffxu@google.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-hardening@vger.kernel.org Subject: [PATCH v1 4/6] PKEY:selftest pkey_enforce_api for mprotect Date: Fri, 19 May 2023 01:19:12 +0000 Message-ID: <20230519011915.846407-5-jeffxu@chromium.org> X-Mailer: git-send-email 2.40.1.698.g37aff9b760-goog In-Reply-To: <20230519011915.846407-1-jeffxu@chromium.org> References: <20230519011915.846407-1-jeffxu@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org From: Jeff Xu Add selftest for pkey_enforce_api for mprotect. Signed-off-by: Jeff Xu --- tools/testing/selftests/mm/Makefile | 1 + tools/testing/selftests/mm/pkey_enforce_api.c | 875 ++++++++++++++++++ 2 files changed, 876 insertions(+) create mode 100644 tools/testing/selftests/mm/pkey_enforce_api.c diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile index 23af4633f0f4..93437a394128 100644 --- a/tools/testing/selftests/mm/Makefile +++ b/tools/testing/selftests/mm/Makefile @@ -71,6 +71,7 @@ CAN_BUILD_X86_64 := $(shell ./../x86/check_cc.sh "$(CC)" ../x86/trivial_64bit_pr CAN_BUILD_WITH_NOPIE := $(shell ./../x86/check_cc.sh "$(CC)" ../x86/trivial_program.c -no-pie) VMTARGETS := protection_keys +VMTARGETS += pkey_enforce_api BINARIES_32 := $(VMTARGETS:%=%_32) BINARIES_64 := $(VMTARGETS:%=%_64) diff --git a/tools/testing/selftests/mm/pkey_enforce_api.c b/tools/testing/selftests/mm/pkey_enforce_api.c new file mode 100644 index 000000000000..23663c89bc9c --- /dev/null +++ b/tools/testing/selftests/mm/pkey_enforce_api.c @@ -0,0 +1,875 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Tests pkey_enforce_api + * + * Compile like this: + * gcc -mxsave -o pkey_enforce_api -O2 -g -std=gnu99 -pthread -Wall pkey_enforce_api.c \ + * -lrt -ldl -lm + * gcc -mxsave -m32 -o pkey_enforce_api_32 -O2 -g -std=gnu99 -pthread -Wall pkey_enforce_api.c \ + * -lrt -ldl -lm + */ +#define _GNU_SOURCE +#define __SANE_USERSPACE_TYPES__ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "../kselftest.h" +#include + +#if defined(__i386__) || defined(__x86_64__) /* arch */ + +#define dprintf0(args...) +#define dprintf1(args...) +#define dprintf2(args...) +#define dprintf3(args...) +#define dprintf4(args...) + +#ifndef u16 +#define u16 __u16 +#endif + +#ifndef u32 +#define u32 __u32 +#endif + +#ifndef u64 +#define u64 __u64 +#endif + +#ifndef PTR_ERR_ENOTSUP +#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP) +#endif + +int read_ptr(int *ptr) +{ + return *ptr; +} + +void expected_pkey_fault(int pkey) +{ +} + +#include "pkey-x86.h" + +#ifndef PKEY_ENFORCE_API +#define PKEY_ENFORCE_API 1 +#endif + +#define PKEY_MASK (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE) + +#define LOG_TEST_ENTER(x) \ + { \ + printf("%s, enforce=%d\n", __func__, x); \ + } +static inline u64 set_pkey_bits(u64 reg, int pkey, u64 flags) +{ + u32 shift = pkey_bit_position(pkey); + /* mask out bits from pkey in old value */ + reg &= ~((u64)PKEY_MASK << shift); + /* OR in new bits for pkey */ + reg |= (flags & PKEY_MASK) << shift; + return reg; +} + +static inline u64 get_pkey_bits(u64 reg, int pkey) +{ + u32 shift = pkey_bit_position(pkey); + /* + * shift down the relevant bits to the lowest two, then + * mask off all the other higher bits + */ + return ((reg >> shift) & PKEY_MASK); +} + +static u32 get_pkey(int pkey) +{ + return (u32)get_pkey_bits(__read_pkey_reg(), pkey); +} + +static void set_pkey(int pkey, unsigned long pkey_value) +{ + u32 mask = (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE); + u64 new_pkey_reg; + + assert(!(pkey_value & ~mask)); + new_pkey_reg = set_pkey_bits(__read_pkey_reg(), pkey, pkey_value); + __write_pkey_reg(new_pkey_reg); +} + +void pkey_disable_set(int pkey, int value) +{ + int pkey_new; + + assert(value & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)); + + pkey_new = get_pkey(pkey); + pkey_new |= value; + set_pkey(pkey, pkey_new); +} + +void pkey_disable_clear(int pkey, int value) +{ + int pkey_new; + + assert(value & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)); + + pkey_new = get_pkey(pkey); + pkey_new &= ~value; + + set_pkey(pkey, pkey_new); +} + +void pkey_write_allow(int pkey) +{ + pkey_disable_clear(pkey, PKEY_DISABLE_WRITE); +} +void pkey_write_deny(int pkey) +{ + pkey_disable_set(pkey, PKEY_DISABLE_WRITE); +} +void pkey_access_allow(int pkey) +{ + pkey_disable_clear(pkey, PKEY_DISABLE_ACCESS); +} +void pkey_access_deny(int pkey) +{ + pkey_disable_set(pkey, PKEY_DISABLE_ACCESS); +} + +int sys_mprotect(void *ptr, size_t size, unsigned long prot) +{ + int sret; + + errno = 0; + sret = syscall(SYS_mprotect, ptr, size, prot); + return sret; +} + +int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot, + unsigned long pkey) +{ + int sret; + + errno = 0; + sret = syscall(SYS_mprotect_key, ptr, size, orig_prot, pkey); + return sret; +} + +int sys_pkey_alloc(unsigned long flags, unsigned long init_val) +{ + int ret = syscall(SYS_pkey_alloc, flags, init_val); + return ret; +} + +int sys_pkey_free(unsigned long pkey) +{ + int ret = syscall(SYS_pkey_free, pkey); + return ret; +} + +bool can_create_pkey(void) +{ + int pkey; + + pkey = sys_pkey_alloc(0, 0); + if (pkey <= 0) + return false; + + sys_pkey_free(pkey); + return true; +} + +static inline int is_pkeys_supported(void) +{ + /* check if the cpu supports pkeys */ + if (!cpu_has_pkeys() || !can_create_pkey()) + return 0; + return 1; +} + +int pkey_alloc_with_check(bool enforce) +{ + int pkey; + + if (enforce) + pkey = sys_pkey_alloc(PKEY_ENFORCE_API, 0); + else + pkey = sys_pkey_alloc(0, 0); + + assert(pkey > 0); + return pkey; +} + +void *addr1 = (void *)0x5000000; +void *addr2 = (void *)0x5001000; +void *addr3 = (void *)0x5002000; +void *addr4 = (void *)0x5003000; + +void setup_single_address_with_pkey(bool enforce, int size, int *pkeyOut, + void **ptrOut) +{ + int pkey; + void *ptr; + int ret; + + pkey = pkey_alloc_with_check(enforce); + + ptr = mmap(NULL, size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + assert(ptr != (void *)-1); + + // assign pkey to the memory. + ret = sys_mprotect_pkey((void *)ptr, size, PROT_READ, pkey); + assert(!ret); + + *pkeyOut = pkey; + *ptrOut = ptr; +} + +void setup_single_fixed_address_with_pkey(bool enforce, int size, int *pkeyOut, + void **ptrOut) +{ + int pkey; + void *ptr; + int ret; + + pkey = pkey_alloc_with_check(enforce); + + ptr = mmap(addr1, size, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + assert(ptr == (void *)addr1); + + // assign pkey to the memory. + ret = sys_mprotect_pkey((void *)ptr, size, PROT_READ, pkey); + assert(!ret); + + *pkeyOut = pkey; + *ptrOut = ptr; +} + +void clean_single_address_with_pkey(int pkey, void *ptr, int size) +{ + int ret; + + ret = munmap(ptr, size); + assert(!ret); + + ret = sys_pkey_free(pkey); + assert(ret == 0); +} + +void setup_two_continues_fixed_address_with_pkey(bool enforce, int size, + int *pkeyOut, void **ptrOut, + void **ptr2Out) +{ + void *ptr; + void *ptr2; + int pkey; + int ret; + + pkey = pkey_alloc_with_check(enforce); + + ptr = mmap(addr1, size, PROT_READ, + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); + assert(ptr == addr1); + + ptr2 = mmap(addr2, size, PROT_READ, + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); + assert(ptr2 == addr2); + + // assign pkey to both addresses in the same call (merged) + ret = sys_mprotect_pkey(ptr, size * 2, + PROT_READ | PROT_WRITE | PROT_EXEC, pkey); + assert(!ret); + *pkeyOut = pkey; + *ptrOut = ptr; + *ptr2Out = ptr2; +} + +void clean_two_address_with_pkey(int size, int pkey, void *ptr, void *ptr2) +{ + int ret; + + ret = munmap(ptr, size); + assert(!ret); + + ret = munmap(ptr2, size); + assert(!ret); + + ret = sys_pkey_free(pkey); + assert(ret == 0); +} + +// pkey_alloc with flags. +void test_pkey_alloc(bool enforce) +{ + int ret; + + LOG_TEST_ENTER(enforce); + + ret = sys_pkey_alloc(0, 0); + assert(ret > 0); + ret = sys_pkey_free(ret); + assert(ret == 0); + + if (enforce) { + ret = sys_pkey_alloc(PKEY_ENFORCE_API, 0); + assert(ret > 0); + ret = sys_pkey_free(ret); + assert(ret == 0); + + // invalid flag. + ret = sys_pkey_alloc(0x4, 0); + assert(ret != 0); + } +} + +// mmap one address. +// assign pkey on the address. +// mprotect is denied when no-writeable PKRU in enforce mode. +void test_mprotect_single_address(bool enforce) +{ + int pkey; + int ret; + void *ptr; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_single_fixed_address_with_pkey(enforce, size, &pkey, &ptr); + + // disable write access. + pkey_write_deny(pkey); + + ret = sys_mprotect_pkey(ptr, size, PROT_READ | PROT_WRITE, pkey); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE); + if (enforce) + assert(ret < 0); + else + assert(ret == 0); + + pkey_write_allow(pkey); + + ret = sys_mprotect_pkey(ptr, size, PROT_READ, pkey); + assert(!ret); + + ret = sys_mprotect(ptr, size, PROT_READ); + assert(ret == 0); + + clean_single_address_with_pkey(pkey, ptr, size); +} + +// mmap two address (continuous two pages). +// assign PKEY to them with one mprotect_pkey call (merged address). +// mprotect is denied when non-writeable PKRU in enforce mode. +void test_mprotect_two_address_merge(bool enforce) +{ + int pkey; + int ret; + void *ptr; + void *ptr2; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_two_continues_fixed_address_with_pkey(enforce, size, &pkey, &ptr, + &ptr2); + + // disable write. + pkey_write_deny(pkey); + + // modify the protection on both addresses (merged). + ret = sys_mprotect(ptr, size * 2, PROT_READ | PROT_WRITE | PROT_EXEC); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + ret = sys_mprotect_pkey(ptr, size * 2, + PROT_READ | PROT_WRITE | PROT_EXEC, pkey); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + // modify the protection on both addresses (merged). + ret = sys_mprotect(ptr, size * 2, PROT_READ | PROT_WRITE | PROT_EXEC); + assert(!ret); + + ret = sys_mprotect_pkey(ptr, size * 2, + PROT_READ | PROT_WRITE | PROT_EXEC, pkey); + assert(!ret); + + clean_two_address_with_pkey(size, pkey, ptr, ptr2); +} + +void setup_two_continues_fixed_address_protect_second_with_pkey( + bool enforce, int size, int *pkeyOut, void **ptrOut, void **ptr2Out) +{ + void *ptr; + void *ptr2; + int pkey; + int ret; + + LOG_TEST_ENTER(enforce); + + pkey = pkey_alloc_with_check(enforce); + + // mmap two addresses (continuous two pages). + ptr = mmap(addr1, size, PROT_READ, + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); + assert(ptr == addr1); + + ptr2 = mmap(addr2, size, PROT_READ, + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); + assert(ptr2 == addr2); + + // assign pkey to the second page. + ret = sys_mprotect_pkey(addr2, size, PROT_READ | PROT_WRITE | PROT_EXEC, + pkey); + assert(!ret); + + *pkeyOut = pkey; + *ptrOut = ptr; + *ptr2Out = ptr2; +} + +// mmap two address (continuous two pages). +// assign PKEY to the second address. +// mprotect on the second address is denied properly. +// mprotect on both addresses (merged) is denied properly. +void test_mprotect_two_address_deny_second(bool enforce) +{ + int pkey; + int ret; + void *ptr; + void *ptr2; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_two_continues_fixed_address_protect_second_with_pkey( + enforce, size, &pkey, &ptr, &ptr2); + + // disable write through pkey. + pkey_write_deny(pkey); + + // modify the first addr is allowed. + ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE | PROT_EXEC); + assert(!ret); + + // modify the second mmap is protected by pkey. + ret = sys_mprotect(ptr2, size, PROT_READ | PROT_WRITE | PROT_EXEC); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + // mprotect both addresses (merged). + ret = sys_mprotect_pkey(ptr, size * 2, + PROT_READ | PROT_WRITE | PROT_EXEC, pkey); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + ret = sys_mprotect(ptr, size * 2, PROT_READ | PROT_WRITE | PROT_EXEC); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + ret = sys_mprotect_pkey(ptr, size * 2, PROT_READ, pkey); + assert(!ret); + + ret = sys_mprotect(ptr, size * 2, PROT_READ); + assert(!ret); + + clean_two_address_with_pkey(size, pkey, ptr, ptr2); +} + +void setup_4pages_fixed_protect_second_page(bool enforce, int size, + int *pkeyOut, void **ptrOut, + void **ptr2Out, void **ptr3Out) +{ + int pkey; + int ret; + void *ptr; + + pkey = pkey_alloc_with_check(enforce); + + // allocate 4 pages. + ptr = mmap(addr1, size * 4, PROT_READ, + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); + assert(ptr == addr1); + + // assign pkey to the second address. + ret = sys_mprotect_pkey(addr2, size, PROT_READ | PROT_WRITE | PROT_EXEC, + pkey); + assert(!ret); + + *pkeyOut = pkey; + *ptrOut = ptr; + *ptr2Out = addr2; + *ptr3Out = addr3; +} + +// mmap one address with 4 pages. +// assign PKEY to the second page only. +// mprotect on the first page is allowed. +// mprotect on the second page is protected in enforce mode. +// mprotect on memory range that includes the second pages is protected. +void test_mprotect_vma_middle_addr(bool enforce) +{ + int pkey; + int ret; + void *ptr, *ptr2, *ptr3; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_4pages_fixed_protect_second_page(enforce, size, &pkey, &ptr, + &ptr2, &ptr3); + + // disable write through pkey. + pkey_write_deny(pkey); + + // modify to the first page is allowed. + ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE | PROT_EXEC); + assert(!ret); + + // modify to the third page is allowed. + ret = sys_mprotect(ptr3, size, PROT_READ | PROT_WRITE | PROT_EXEC); + assert(!ret); + + // modify to the second page is protected by pkey. + ret = sys_mprotect(ptr2, size, PROT_READ | PROT_WRITE | PROT_EXEC); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + // modify to memory range that includes the second page is protected. + ret = sys_mprotect_pkey(ptr, size * 4, + PROT_READ | PROT_WRITE | PROT_EXEC, pkey); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + ret = sys_mprotect(ptr, size * 4, PROT_READ | PROT_WRITE | PROT_EXEC); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + ret = sys_mprotect(addr2, size, PROT_READ | PROT_WRITE | PROT_EXEC); + assert(!ret); + + ret = sys_mprotect_pkey(ptr, size * 4, + PROT_READ | PROT_WRITE | PROT_EXEC, pkey); + assert(!ret); + + clean_single_address_with_pkey(pkey, ptr, size * 4); +} + +// mmap one address with 4 pages. +// assign PKEY to the second page only. +// mprotect on the second page, but size is unaligned. +void test_mprotect_unaligned(bool enforce) +{ + int pkey; + int ret; + void *ptr, *ptr2, *ptr3; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_4pages_fixed_protect_second_page(enforce, size, &pkey, &ptr, + &ptr2, &ptr3); + + // disable write through pkey. + pkey_write_deny(pkey); + + // modify to the first page is allowed. + ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE | PROT_EXEC); + assert(!ret); + + // modify to the second page is protected by pkey. + ret = sys_mprotect(ptr2, size - 1, PROT_READ | PROT_WRITE | PROT_EXEC); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + ret = sys_mprotect(addr2, size - 1, PROT_READ | PROT_WRITE | PROT_EXEC); + assert(!ret); + + clean_single_address_with_pkey(pkey, ptr, size * 4); +} + +// mmap one address with 4 pages. +// assign PKEY to the second page only. +// mprotect on the second page, but size is unaligned. +void test_mprotect_unaligned2(bool enforce) +{ + int pkey; + int ret; + void *ptr, *ptr2, *ptr3; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_4pages_fixed_protect_second_page(enforce, size, &pkey, &ptr, + &ptr2, &ptr3); + + // disable write through pkey. + pkey_write_deny(pkey); + + // modify to the first page is allowed. + ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE | PROT_EXEC); + assert(!ret); + + // modify to the second page is protected by pkey. + ret = sys_mprotect(ptr2, size + 1, PROT_READ | PROT_WRITE | PROT_EXEC); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + ret = sys_mprotect(addr2, size + 1, PROT_READ | PROT_WRITE | PROT_EXEC); + assert(!ret); + + clean_single_address_with_pkey(pkey, ptr, size * 4); +} + +void setup_address_with_gap_two_pkeys(bool enforce, int size, int *pkeyOut, + int *pkey2Out, void **ptrOut, + void **ptr2Out) +{ + int pkey, pkey2; + void *ptr, *ptr2; + int ret; + + pkey = pkey_alloc_with_check(enforce); + pkey2 = pkey_alloc_with_check(enforce); + + ptr = mmap(addr1, size, PROT_READ, + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); + assert(ptr == (void *)addr1); + + ptr2 = mmap(addr3, size, PROT_READ, + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); + assert(ptr2 == (void *)addr3); + + // assign pkey to the memory. + ret = sys_mprotect_pkey((void *)ptr, size, PROT_READ, pkey); + assert(!ret); + + // assign pkey to the memory. + ret = sys_mprotect_pkey((void *)ptr2, size, PROT_READ, pkey2); + assert(!ret); + + *pkeyOut = pkey; + *ptrOut = ptr; + + *pkey2Out = pkey2; + *ptr2Out = ptr2; +} + +void clean_address_with_pag_two_pkeys(int pkey, void *ptr, int pkey2, + void *ptr2, int size) +{ + int ret; + + ret = munmap(ptr, size); + assert(!ret); + + ret = sys_pkey_free(pkey); + assert(ret == 0); + + ret = munmap(ptr2, size); + assert(!ret); + + ret = sys_pkey_free(pkey2); + assert(ret == 0); +} + +// mmap two addresses, with a page gap between two. +// assign pkeys on both address. +// disable access to the second address. +// mprotect from start of address1 to the end of address 2, +// because there is a gap in the memory range, mprotect will fail. +void test_mprotect_gapped_address_with_two_pkeys(bool enforce) +{ + int pkey, pkey2; + int ret; + void *ptr, *ptr2; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_address_with_gap_two_pkeys(enforce, size, &pkey, &pkey2, &ptr, + &ptr2); + + // disable write access. + pkey_write_deny(pkey2); + + ret = sys_mprotect_pkey(ptr, size * 3, PROT_READ | PROT_WRITE, pkey); + assert(ret < 0); + + ret = sys_mprotect(ptr, size * 3, PROT_READ | PROT_WRITE); + assert(ret < 0); + + pkey_write_allow(pkey2); + + ret = sys_mprotect_pkey(ptr, size * 3, PROT_READ, pkey); + assert(ret < 0); + + ret = sys_mprotect(ptr, size * 3, PROT_READ); + assert(ret < 0); + + clean_address_with_pag_two_pkeys(pkey, ptr, pkey2, ptr2, size); +} + +struct thread_info { + int pkey; + void *addr; + int size; + bool enforce; +}; + +void *thread_mprotect(void *arg) +{ + struct thread_info *tinfo = arg; + void *ptr = tinfo->addr; + int size = tinfo->size; + bool enforce = tinfo->enforce; + int pkey = tinfo->pkey; + int ret; + + // disable write access. + pkey_write_deny(pkey); + ret = sys_mprotect_pkey(ptr, size, PROT_READ | PROT_WRITE, pkey); + + if (enforce) + assert(ret < 0); + else + assert(!ret); + + ret = sys_mprotect(ptr, size, PROT_READ | PROT_WRITE); + if (enforce) + assert(ret < 0); + else + assert(ret == 0); + + pkey_write_allow(pkey); + + ret = sys_mprotect_pkey(ptr, size, PROT_READ, pkey); + assert(!ret); + + ret = sys_mprotect(ptr, size, PROT_READ); + assert(ret == 0); + return NULL; +} + +// mmap one address. +// assign pkey on the address. +// in child thread, mprotect is denied when no-writeable PKRU in enforce mode. +void test_mprotect_child_thread(bool enforce) +{ + int pkey; + int ret; + void *ptr; + int size = PAGE_SIZE; + pthread_t thread; + struct thread_info tinfo; + + LOG_TEST_ENTER(enforce); + + setup_single_fixed_address_with_pkey(enforce, size, &pkey, &ptr); + tinfo.size = size; + tinfo.addr = ptr; + tinfo.enforce = enforce; + tinfo.pkey = pkey; + + ret = pthread_create(&thread, NULL, thread_mprotect, (void *)&tinfo); + assert(ret == 0); + pthread_join(thread, NULL); + + clean_single_address_with_pkey(pkey, ptr, size); +} + +void test_enforce_api(void) +{ + for (int i = 0; i < 2; i++) { + bool enforce = (i == 1); + + test_pkey_alloc(enforce); + + test_mprotect_single_address(enforce); + test_mprotect_two_address_merge(enforce); + test_mprotect_two_address_deny_second(enforce); + test_mprotect_vma_middle_addr(enforce); + test_mprotect_unaligned(enforce); + test_mprotect_unaligned2(enforce); + test_mprotect_child_thread(enforce); + test_mprotect_gapped_address_with_two_pkeys(enforce); + } +} + +int main(void) +{ + int pkeys_supported = is_pkeys_supported(); + + printf("pid: %d\n", getpid()); + printf("has pkeys: %d\n", pkeys_supported); + if (!pkeys_supported) { + printf("PKEY not supported, skip the test.\n"); + exit(0); + } + + test_enforce_api(); + printf("done (all tests OK)\n"); + return 0; +} +#else /* arch */ +int main(void) +{ + printf("SKIP: not supported arch\n"); + return 0; +} +#endif /* arch */ From patchwork Fri May 19 01:19:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Xu X-Patchwork-Id: 13247592 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C4D9BC7EE33 for ; 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[35.230.43.183]) by smtp.gmail.com with UTF8SMTPSA id ji17-20020a170903325100b001960706141fsm2102839plb.149.2023.05.18.18.19.31 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 18 May 2023 18:19:31 -0700 (PDT) From: jeffxu@chromium.org To: dave.hansen@intel.com, luto@kernel.org, jorgelo@chromium.org, keescook@chromium.org, groeck@chromium.org, jannh@google.com, sroettger@google.com Cc: akpm@linux-foundation.org, jeffxu@google.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-hardening@vger.kernel.org Subject: [PATCH v1 5/6] PKEY: Apply PKEY_ENFORCE_API to munmap Date: Fri, 19 May 2023 01:19:13 +0000 Message-ID: <20230519011915.846407-6-jeffxu@chromium.org> X-Mailer: git-send-email 2.40.1.698.g37aff9b760-goog In-Reply-To: <20230519011915.846407-1-jeffxu@chromium.org> References: <20230519011915.846407-1-jeffxu@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org From: Jeff Xu This patch enables PKEY_ENFORCE_API for the munmap syscall. Signed-off-by: Jeff Xu --- include/linux/mm.h | 8 +++++++- mm/mmap.c | 31 +++++++++++++++++++++++-------- mm/mremap.c | 6 ++++-- 3 files changed, 34 insertions(+), 11 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 27ce77080c79..795cdeee2ea7 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -429,6 +429,12 @@ extern unsigned int kobjsize(const void *objp); #endif #define VM_FLAGS_CLEAR (ARCH_VM_PKEY_FLAGS | VM_ARCH_CLEAR) +/* The current call stack is originated from user space or kernel */ +enum caller_origin { + ON_BEHALF_OF_KERNEL = 0, + ON_BEHALF_OF_USERSPACE, +}; + /* * mapping from the currently active vm_flags protection bits (the * low four bits) to a page protection mask.. @@ -3136,7 +3142,7 @@ extern unsigned long do_mmap(struct file *file, unsigned long addr, unsigned long pgoff, unsigned long *populate, struct list_head *uf); extern int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm, unsigned long start, size_t len, struct list_head *uf, - bool downgrade); + bool downgrade, enum caller_origin called); extern int do_munmap(struct mm_struct *, unsigned long, size_t, struct list_head *uf); extern int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior); diff --git a/mm/mmap.c b/mm/mmap.c index 13678edaa22c..3de95a6a4397 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2498,6 +2498,7 @@ do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma, * @uf: The userfaultfd list_head * @downgrade: set to true if the user wants to attempt to write_downgrade the * mmap_lock + * @called: originated from user space or kernel * * This function takes a @mas that is either pointing to the previous VMA or set * to MA_START and sets it up to remove the mapping(s). The @len will be @@ -2507,7 +2508,7 @@ do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma, */ int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm, unsigned long start, size_t len, struct list_head *uf, - bool downgrade) + bool downgrade, enum caller_origin called) { unsigned long end; struct vm_area_struct *vma; @@ -2519,6 +2520,15 @@ int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm, if (end == start) return -EINVAL; + /* + * When called by syscall from userspace, check if the calling + * thread has the PKEY permission to modify the memory mapping. + */ + if (called == ON_BEHALF_OF_USERSPACE && + arch_check_pkey_enforce_api(mm, start, end) < 0) { + return -EACCES; + } + /* arch_unmap() might do unmaps itself. */ arch_unmap(mm, start, end); @@ -2541,7 +2551,7 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len, { VMA_ITERATOR(vmi, mm, start); - return do_vmi_munmap(&vmi, mm, start, len, uf, false); + return do_vmi_munmap(&vmi, mm, start, len, uf, false, ON_BEHALF_OF_KERNEL); } unsigned long mmap_region(struct file *file, unsigned long addr, @@ -2575,7 +2585,8 @@ unsigned long mmap_region(struct file *file, unsigned long addr, } /* Unmap any existing mapping in the area */ - if (do_vmi_munmap(&vmi, mm, addr, len, uf, false)) + if (do_vmi_munmap(&vmi, mm, addr, len, uf, false, + ON_BEHALF_OF_KERNEL)) return -ENOMEM; /* @@ -2792,7 +2803,11 @@ unsigned long mmap_region(struct file *file, unsigned long addr, return error; } -static int __vm_munmap(unsigned long start, size_t len, bool downgrade) +/* + * @called: originated from user space or kernel + */ +static int __vm_munmap(unsigned long start, size_t len, bool downgrade, + enum caller_origin called) { int ret; struct mm_struct *mm = current->mm; @@ -2802,7 +2817,7 @@ static int __vm_munmap(unsigned long start, size_t len, bool downgrade) if (mmap_write_lock_killable(mm)) return -EINTR; - ret = do_vmi_munmap(&vmi, mm, start, len, &uf, downgrade); + ret = do_vmi_munmap(&vmi, mm, start, len, &uf, downgrade, called); /* * Returning 1 indicates mmap_lock is downgraded. * But 1 is not legal return value of vm_munmap() and munmap(), reset @@ -2820,14 +2835,14 @@ static int __vm_munmap(unsigned long start, size_t len, bool downgrade) int vm_munmap(unsigned long start, size_t len) { - return __vm_munmap(start, len, false); + return __vm_munmap(start, len, false, ON_BEHALF_OF_KERNEL); } EXPORT_SYMBOL(vm_munmap); SYSCALL_DEFINE2(munmap, unsigned long, addr, size_t, len) { addr = untagged_addr(addr); - return __vm_munmap(addr, len, true); + return __vm_munmap(addr, len, true, ON_BEHALF_OF_USERSPACE); } @@ -3055,7 +3070,7 @@ int vm_brk_flags(unsigned long addr, unsigned long request, unsigned long flags) if (ret) goto limits_failed; - ret = do_vmi_munmap(&vmi, mm, addr, len, &uf, 0); + ret = do_vmi_munmap(&vmi, mm, addr, len, &uf, 0, ON_BEHALF_OF_KERNEL); if (ret) goto munmap_failed; diff --git a/mm/mremap.c b/mm/mremap.c index b11ce6c92099..a3f576effbb1 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -703,7 +703,8 @@ static unsigned long move_vma(struct vm_area_struct *vma, } vma_iter_init(&vmi, mm, old_addr); - if (do_vmi_munmap(&vmi, mm, old_addr, old_len, uf_unmap, false) < 0) { + if (do_vmi_munmap(&vmi, mm, old_addr, old_len, uf_unmap, false, + ON_BEHALF_OF_KERNEL) < 0) { /* OOM: unable to split vma, just get accounts right */ if (vm_flags & VM_ACCOUNT && !(flags & MREMAP_DONTUNMAP)) vm_acct_memory(old_len >> PAGE_SHIFT); @@ -993,7 +994,8 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, VMA_ITERATOR(vmi, mm, addr + new_len); retval = do_vmi_munmap(&vmi, mm, addr + new_len, - old_len - new_len, &uf_unmap, true); + old_len - new_len, &uf_unmap, true, + ON_BEHALF_OF_KERNEL); /* Returning 1 indicates mmap_lock is downgraded to read. */ if (retval == 1) { downgraded = true; From patchwork Fri May 19 01:19:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Xu X-Patchwork-Id: 13247593 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D937FC7EE43 for ; 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[35.230.43.183]) by smtp.gmail.com with UTF8SMTPSA id p15-20020a63c14f000000b00528db73ed70sm1870456pgi.3.2023.05.18.18.19.31 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 18 May 2023 18:19:32 -0700 (PDT) From: jeffxu@chromium.org To: dave.hansen@intel.com, luto@kernel.org, jorgelo@chromium.org, keescook@chromium.org, groeck@chromium.org, jannh@google.com, sroettger@google.com Cc: akpm@linux-foundation.org, jeffxu@google.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-hardening@vger.kernel.org Subject: [PATCH v1 6/6] PKEY:selftest pkey_enforce_api for munmap Date: Fri, 19 May 2023 01:19:14 +0000 Message-ID: <20230519011915.846407-7-jeffxu@chromium.org> X-Mailer: git-send-email 2.40.1.698.g37aff9b760-goog In-Reply-To: <20230519011915.846407-1-jeffxu@chromium.org> References: <20230519011915.846407-1-jeffxu@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org From: Jeff Xu Add selftest for pkey_enforce_api for mprotect Signed-off-by: Jeff Xu --- tools/testing/selftests/mm/pkey_enforce_api.c | 437 ++++++++++++++++++ 1 file changed, 437 insertions(+) diff --git a/tools/testing/selftests/mm/pkey_enforce_api.c b/tools/testing/selftests/mm/pkey_enforce_api.c index 23663c89bc9c..92aa29248e1f 100644 --- a/tools/testing/selftests/mm/pkey_enforce_api.c +++ b/tools/testing/selftests/mm/pkey_enforce_api.c @@ -833,6 +833,429 @@ void test_mprotect_child_thread(bool enforce) clean_single_address_with_pkey(pkey, ptr, size); } +// mmap one address with one page. +// assign PKEY to the address. +// munmap on the address is protected. +void test_munmap_single_address(bool enforce) +{ + int pkey; + int ret; + void *ptr; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_single_address_with_pkey(enforce, size, &pkey, &ptr); + + // disable write access. + pkey_write_deny(pkey); + + ret = munmap(ptr, size); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + if (enforce) { + ret = munmap(ptr, size); + assert(!ret); + } + + clean_single_address_with_pkey(pkey, ptr, size); +} + +// mmap two address (continuous two pages). +// assign PKEY to them with one mprotect_pkey call (merged address). +// munmap two address in one call (merged address). +void test_munmap_two_address_merge(bool enforce) +{ + int pkey; + int ret; + void *ptr; + void *ptr2; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_two_continues_fixed_address_with_pkey(enforce, size, &pkey, &ptr, + &ptr2); + + // disable write. + pkey_write_deny(pkey); + + // munmap on both addresses with one call (merged). + ret = munmap(ptr, size * 2); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + if (enforce) { + ret = munmap(ptr, size * 2); + assert(!ret); + } + + ret = sys_pkey_free(pkey); + assert(ret == 0); +} + +// mmap two address (continuous two pages). +// assign PKEY to the second address. +// munmap on the second address is protected. +void test_munmap_two_address_deny_second(bool enforce) +{ + int pkey; + int ret; + void *ptr; + void *ptr2; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_two_continues_fixed_address_protect_second_with_pkey( + enforce, size, &pkey, &ptr, &ptr2); + + // disable write through pkey. + pkey_write_deny(pkey); + + ret = munmap(ptr2, size); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + ret = munmap(ptr, size); + assert(!ret); + + pkey_write_allow(pkey); + + if (enforce) { + ret = munmap(ptr2, size); + assert(!ret); + } + + ret = sys_pkey_free(pkey); + assert(ret == 0); +} + +// mmap two address (continuous two pages). +// assign PKEY to the second address. +// munmap on the range that includes the second address. +void test_munmap_two_address_deny_range(bool enforce) +{ + int pkey; + int ret; + void *ptr; + void *ptr2; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_two_continues_fixed_address_protect_second_with_pkey( + enforce, size, &pkey, &ptr, &ptr2); + + // disable write through pkey. + pkey_write_deny(pkey); + + ret = munmap(ptr, size * 2); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + if (enforce) { + ret = munmap(ptr, size * 2); + assert(!ret); + } + + ret = sys_pkey_free(pkey); + assert(ret == 0); +} + +// mmap one address with 4 pages. +// assign PKEY to the second page only. +// munmap on memory range that includes the second pages is protected. +void test_munmap_vma_middle_addr(bool enforce) +{ + int pkey; + int ret; + void *ptr, *ptr2, *ptr3; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_4pages_fixed_protect_second_page(enforce, size, &pkey, &ptr, + &ptr2, &ptr3); + + // disable write through pkey. + pkey_write_deny(pkey); + + // munmap support merge, we are going to make sure we don't regress. + ret = munmap(addr1, size * 4); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + if (enforce) { + ret = munmap(ptr, size * 4); + assert(!ret); + } + + ret = sys_pkey_free(pkey); + assert(ret == 0); +} + +// mmap one address with 4 pages. +// assign PKEY to the second page only. +// munmap from 2nd page. +void test_munmap_shrink(bool enforce) +{ + int pkey; + int ret; + void *ptr, *ptr2, *ptr3; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_4pages_fixed_protect_second_page(enforce, size, &pkey, &ptr, + &ptr2, &ptr3); + + // disable write through pkey. + pkey_write_deny(pkey); + + // munmap support merge, we are going to make sure we don't regress. + ret = munmap(ptr2, size * 3); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + if (enforce) { + ret = munmap(ptr2, size * 3); + assert(!ret); + } + + ret = munmap(ptr, size); + assert(!ret); + + ret = sys_pkey_free(pkey); + assert(ret == 0); +} + +// mmap one address with 4 pages. +// assign PKEY to the second page only. +// munmap from 2nd page but size is less than one page +void test_munmap_unaligned(bool enforce) +{ + int pkey; + int ret; + void *ptr, *ptr2, *ptr3; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_4pages_fixed_protect_second_page(enforce, size, &pkey, &ptr, + &ptr2, &ptr3); + + // disable write through pkey. + pkey_write_deny(pkey); + + // munmap support merge, we are going to make sure we don't regress. + ret = munmap(ptr2, size - 1); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + if (enforce) { + ret = munmap(ptr2, size - 1); + assert(!ret); + } + + ret = munmap(ptr, size * 4); + assert(!ret); + + ret = sys_pkey_free(pkey); + assert(ret == 0); +} + +// mmap one address with 4 pages. +// assign PKEY to the second page only. +// munmap from 2nd page but size is less than one page +void test_munmap_unaligned2(bool enforce) +{ + int pkey; + int ret; + void *ptr, *ptr2, *ptr3; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_4pages_fixed_protect_second_page(enforce, size, &pkey, &ptr, + &ptr2, &ptr3); + + // disable write through pkey. + pkey_write_deny(pkey); + + // munmap support merge, we are going to make sure we don't regress. + ret = munmap(ptr2, size + 1); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + if (enforce) { + ret = munmap(ptr2, size + 1); + assert(!ret); + } + + ret = munmap(ptr, size * 4); + assert(!ret); + + ret = sys_pkey_free(pkey); + assert(ret == 0); +} + +// mmap one address with one page. +// assign PKEY to the address. +// munmap on the address but with size of 4 pages(should OK). +void test_munmap_outbound_addr(bool enforce) +{ + int pkey; + int ret; + void *ptr; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_single_fixed_address_with_pkey(enforce, size, &pkey, &ptr); + + // disable write through pkey. + pkey_write_deny(pkey); + + // Interesting enough, this is allowed, even the other 3 pages are not allocated. + ret = munmap(addr1, size * 4); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey); + + if (enforce) { + ret = munmap(addr1, size * 4); + assert(!ret); + } + + clean_single_address_with_pkey(pkey, ptr, size); +} +// mmap two addresses, with a page gap between two. +// assign pkeys on both address. +// disable access to the second address. +// munmap from start of address1 to the end of address 2, +// because there is a gap in the memory range, mprotect will fail. +void test_munmap_gapped_address_with_two_pkeys(bool enforce) +{ + int pkey, pkey2; + int ret; + void *ptr, *ptr2; + int size = PAGE_SIZE; + + LOG_TEST_ENTER(enforce); + + setup_address_with_gap_two_pkeys(enforce, size, &pkey, &pkey2, &ptr, + &ptr2); + + // disable write access. + pkey_write_deny(pkey2); + + // Interesting enough, this is allowed, even there is a gap beween address 1 and 2. + ret = munmap(addr1, size * 3); + if (enforce) + assert(ret < 0); + else + assert(!ret); + + pkey_write_allow(pkey2); + if (enforce) { + ret = munmap(addr1, size * 3); + assert(!ret); + } +} + +// use write-deny pkey and see if program can exit properly. +// This is manual test, run it at end if needed. +void test_exit_munmap_disable_write(void) +{ + int pkey; + int ret; + void *ptr; + int size = PAGE_SIZE; + + pkey = sys_pkey_alloc(PKEY_ENFORCE_API, 0); + assert(pkey > 0); + + // allocate 1 page. + ptr = mmap(addr1, size, PROT_READ, + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); + assert(ptr == addr1); + + // assign pkey to the first address. + ret = sys_mprotect_pkey(ptr, size, PROT_READ | PROT_WRITE | PROT_EXEC, + pkey); + assert(!ret); + + // disable write through pkey. + pkey_write_deny(pkey); + + ret = munmap(ptr, size); + assert(ret < 0); +} + +// use disable-all pkey and see if program can exit properly. +// This is manual test, run it at end if needed. +void test_exit_munmap_disable_all(void) +{ + int pkey; + int ret; + void *ptr; + int size = PAGE_SIZE; + + pkey = sys_pkey_alloc(PKEY_ENFORCE_API, 0); + assert(pkey > 0); + + // allocate 1 page. + ptr = mmap(addr2, size, PROT_READ, + MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -1, 0); + assert(ptr == addr2); + + // assign pkey to the first address. + ret = sys_mprotect_pkey(ptr, size, PROT_READ | PROT_WRITE | PROT_EXEC, + pkey); + assert(!ret); + + // disable write through pkey. + pkey_access_deny(pkey); + + ret = munmap(addr1, size); + assert(ret < 0); +} + void test_enforce_api(void) { for (int i = 0; i < 2; i++) { @@ -848,7 +1271,21 @@ void test_enforce_api(void) test_mprotect_unaligned2(enforce); test_mprotect_child_thread(enforce); test_mprotect_gapped_address_with_two_pkeys(enforce); + + test_munmap_single_address(enforce); + test_munmap_two_address_merge(enforce); + test_munmap_two_address_deny_second(enforce); + test_munmap_two_address_deny_range(enforce); + test_munmap_vma_middle_addr(enforce); + test_munmap_outbound_addr(enforce); + test_munmap_shrink(enforce); + test_munmap_unaligned(enforce); + test_munmap_unaligned2(enforce); + test_munmap_gapped_address_with_two_pkeys(enforce); } + + test_exit_munmap_disable_write(); + test_exit_munmap_disable_all(); } int main(void)