From patchwork Fri Aug 12 15:27:40 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Catalin Marinas X-Patchwork-Id: 73853 Delivered-To: patch@linaro.org Received: by 10.140.29.52 with SMTP id a49csp230807qga; Fri, 12 Aug 2016 08:30:53 -0700 (PDT) X-Received: by 10.98.138.153 with SMTP id o25mr28164140pfk.80.1471015853201; Fri, 12 Aug 2016 08:30:53 -0700 (PDT) Return-Path: Received: from bombadil.infradead.org (bombadil.infradead.org. [2001:1868:205::9]) by mx.google.com with ESMTPS id w10si9420186pfd.81.2016.08.12.08.30.52 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 12 Aug 2016 08:30:53 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) client-ip=2001:1868:205::9; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) smtp.mailfrom=linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bYEOv-0002SE-VU; Fri, 12 Aug 2016 15:29:37 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bYENd-0001i4-P7 for linux-arm-kernel@lists.infradead.org; Fri, 12 Aug 2016 15:28:22 +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 D27AF3ED; Fri, 12 Aug 2016 08:29:25 -0700 (PDT) Received: from e104818-lin.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 37C233F213; Fri, 12 Aug 2016 08:27:55 -0700 (PDT) From: Catalin Marinas To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 1/7] arm64: Factor out PAN enabling/disabling into separate uaccess_* macros Date: Fri, 12 Aug 2016 16:27:40 +0100 Message-Id: <1471015666-23125-2-git-send-email-catalin.marinas@arm.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1471015666-23125-1-git-send-email-catalin.marinas@arm.com> References: <1471015666-23125-1-git-send-email-catalin.marinas@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160812_082817_992494_D5A42C29 X-CRM114-Status: GOOD ( 10.61 ) X-Spam-Score: -8.3 (--------) X-Spam-Report: SpamAssassin version 3.4.0 on bombadil.infradead.org summary: Content analysis details: (-8.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [217.140.101.70 listed in list.dnswl.org] -1.4 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: James Morse , Will Deacon , Kees Cook , kernel-hardening@lists.openwall.com MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org This patch moves the directly coded alternatives for turning PAN on/off into separate uaccess_{enable,disable} macros or functions. The asm macros take a few arguments which will be used in subsequent patches. Cc: Will Deacon Cc: James Morse Cc: Kees Cook Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/assembler.h | 20 ++++++++++++++++++++ arch/arm64/include/asm/futex.h | 14 +++++++------- arch/arm64/include/asm/uaccess.h | 27 +++++++++++++++++++-------- arch/arm64/kernel/armv8_deprecated.c | 10 +++++----- arch/arm64/lib/clear_user.S | 7 ++----- arch/arm64/lib/copy_from_user.S | 7 ++----- arch/arm64/lib/copy_in_user.S | 7 ++----- arch/arm64/lib/copy_to_user.S | 7 ++----- 8 files changed, 59 insertions(+), 40 deletions(-) _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index d5025c69ca81..bbed373f4ab7 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -23,6 +23,7 @@ #ifndef __ASM_ASSEMBLER_H #define __ASM_ASSEMBLER_H +#include #include #include #include @@ -350,4 +351,23 @@ alternative_endif movk \reg, :abs_g0_nc:\val .endm +/* + * User access enabling/disabling macros. + */ + .macro uaccess_disable, tmp1 +alternative_if_not ARM64_ALT_PAN_NOT_UAO + nop +alternative_else + SET_PSTATE_PAN(1) +alternative_endif + .endm + + .macro uaccess_enable, tmp1, tmp2, flags, errata = 0 +alternative_if_not ARM64_ALT_PAN_NOT_UAO + nop +alternative_else + SET_PSTATE_PAN(0) +alternative_endif + .endm + #endif /* __ASM_ASSEMBLER_H */ diff --git a/arch/arm64/include/asm/futex.h b/arch/arm64/include/asm/futex.h index f2585cdd32c2..7e5f236093be 100644 --- a/arch/arm64/include/asm/futex.h +++ b/arch/arm64/include/asm/futex.h @@ -27,9 +27,9 @@ #include #define __futex_atomic_op(insn, ret, oldval, uaddr, tmp, oparg) \ +do { \ + uaccess_enable(ARM64_HAS_PAN); \ asm volatile( \ - ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_HAS_PAN, \ - CONFIG_ARM64_PAN) \ " prfm pstl1strm, %2\n" \ "1: ldxr %w1, %2\n" \ insn "\n" \ @@ -44,11 +44,11 @@ " .popsection\n" \ _ASM_EXTABLE(1b, 4b) \ _ASM_EXTABLE(2b, 4b) \ - ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_HAS_PAN, \ - CONFIG_ARM64_PAN) \ : "=&r" (ret), "=&r" (oldval), "+Q" (*uaddr), "=&r" (tmp) \ : "r" (oparg), "Ir" (-EFAULT) \ - : "memory") + : "memory"); \ + uaccess_disable(ARM64_HAS_PAN); \ +} while (0) static inline int futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr) @@ -118,8 +118,8 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) return -EFAULT; + uaccess_enable(ARM64_HAS_PAN); asm volatile("// futex_atomic_cmpxchg_inatomic\n" -ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_HAS_PAN, CONFIG_ARM64_PAN) " prfm pstl1strm, %2\n" "1: ldxr %w1, %2\n" " sub %w3, %w1, %w4\n" @@ -134,10 +134,10 @@ ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_HAS_PAN, CONFIG_ARM64_PAN) " .popsection\n" _ASM_EXTABLE(1b, 4b) _ASM_EXTABLE(2b, 4b) -ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_HAS_PAN, CONFIG_ARM64_PAN) : "+r" (ret), "=&r" (val), "+Q" (*uaddr), "=&r" (tmp) : "r" (oldval), "r" (newval), "Ir" (-EFAULT) : "memory"); + uaccess_disable(ARM64_HAS_PAN); *uval = val; return ret; diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index 5e834d10b291..f04869630207 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -112,6 +112,21 @@ static inline void set_fs(mm_segment_t fs) " .popsection\n" /* + * User access enabling/disabling. + */ +#define uaccess_disable(alt) \ +do { \ + asm(ALTERNATIVE("nop", SET_PSTATE_PAN(1), alt, \ + CONFIG_ARM64_PAN)); \ +} while (0) + +#define uaccess_enable(alt) \ +do { \ + asm(ALTERNATIVE("nop", SET_PSTATE_PAN(0), alt, \ + CONFIG_ARM64_PAN)); \ +} while (0) + +/* * The "__xxx" versions of the user access functions do not verify the address * space - it must have been done previously with a separate "access_ok()" * call. @@ -138,8 +153,7 @@ static inline void set_fs(mm_segment_t fs) do { \ unsigned long __gu_val; \ __chk_user_ptr(ptr); \ - asm(ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_ALT_PAN_NOT_UAO,\ - CONFIG_ARM64_PAN)); \ + uaccess_enable(ARM64_ALT_PAN_NOT_UAO); \ switch (sizeof(*(ptr))) { \ case 1: \ __get_user_asm("ldrb", "ldtrb", "%w", __gu_val, (ptr), \ @@ -160,9 +174,8 @@ do { \ default: \ BUILD_BUG(); \ } \ + uaccess_disable(ARM64_ALT_PAN_NOT_UAO); \ (x) = (__force __typeof__(*(ptr)))__gu_val; \ - asm(ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_ALT_PAN_NOT_UAO,\ - CONFIG_ARM64_PAN)); \ } while (0) #define __get_user(x, ptr) \ @@ -207,8 +220,7 @@ do { \ do { \ __typeof__(*(ptr)) __pu_val = (x); \ __chk_user_ptr(ptr); \ - asm(ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_ALT_PAN_NOT_UAO,\ - CONFIG_ARM64_PAN)); \ + uaccess_enable(ARM64_ALT_PAN_NOT_UAO); \ switch (sizeof(*(ptr))) { \ case 1: \ __put_user_asm("strb", "sttrb", "%w", __pu_val, (ptr), \ @@ -229,8 +241,7 @@ do { \ default: \ BUILD_BUG(); \ } \ - asm(ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_ALT_PAN_NOT_UAO,\ - CONFIG_ARM64_PAN)); \ + uaccess_disable(ARM64_ALT_PAN_NOT_UAO); \ } while (0) #define __put_user(x, ptr) \ diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c index 42ffdb54e162..3aaf2fafbc8a 100644 --- a/arch/arm64/kernel/armv8_deprecated.c +++ b/arch/arm64/kernel/armv8_deprecated.c @@ -281,9 +281,9 @@ static void __init register_insn_emulation_sysctl(struct ctl_table *table) * Error-checking SWP macros implemented using ldxr{b}/stxr{b} */ #define __user_swpX_asm(data, addr, res, temp, B) \ +do { \ + uaccess_enable(ARM64_HAS_PAN); \ __asm__ __volatile__( \ - ALTERNATIVE("nop", SET_PSTATE_PAN(0), ARM64_HAS_PAN, \ - CONFIG_ARM64_PAN) \ "0: ldxr"B" %w2, [%3]\n" \ "1: stxr"B" %w0, %w1, [%3]\n" \ " cbz %w0, 2f\n" \ @@ -299,11 +299,11 @@ static void __init register_insn_emulation_sysctl(struct ctl_table *table) " .popsection" \ _ASM_EXTABLE(0b, 4b) \ _ASM_EXTABLE(1b, 4b) \ - ALTERNATIVE("nop", SET_PSTATE_PAN(1), ARM64_HAS_PAN, \ - CONFIG_ARM64_PAN) \ : "=&r" (res), "+r" (data), "=&r" (temp) \ : "r" (addr), "i" (-EAGAIN), "i" (-EFAULT) \ - : "memory") + : "memory"); \ + uaccess_disable(ARM64_HAS_PAN); \ +} while (0) #define __user_swp_asm(data, addr, res, temp) \ __user_swpX_asm(data, addr, res, temp, "") diff --git a/arch/arm64/lib/clear_user.S b/arch/arm64/lib/clear_user.S index 5d1cad3ce6d6..10d7501a5ce1 100644 --- a/arch/arm64/lib/clear_user.S +++ b/arch/arm64/lib/clear_user.S @@ -17,7 +17,6 @@ */ #include -#include #include #include #include @@ -33,8 +32,7 @@ * Alignment fixed up by hardware. */ ENTRY(__clear_user) -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_enable x2, x3, x4 mov x2, x1 // save the size for fixup return subs x1, x1, #8 b.mi 2f @@ -54,8 +52,7 @@ uao_user_alternative 9f, strh, sttrh, wzr, x0, 2 b.mi 5f uao_user_alternative 9f, strb, sttrb, wzr, x0, 0 5: mov x0, #0 -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_disable x2 ret ENDPROC(__clear_user) diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index 0b90497d4424..0ba4147fdff8 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -16,7 +16,6 @@ #include -#include #include #include #include @@ -67,12 +66,10 @@ end .req x5 ENTRY(__arch_copy_from_user) -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_enable x3, x4, x6 add end, x0, x2 #include "copy_template.S" -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_disable x3 mov x0, #0 // Nothing to copy ret ENDPROC(__arch_copy_from_user) diff --git a/arch/arm64/lib/copy_in_user.S b/arch/arm64/lib/copy_in_user.S index f7292dd08c84..ecbdaf6aacb8 100644 --- a/arch/arm64/lib/copy_in_user.S +++ b/arch/arm64/lib/copy_in_user.S @@ -18,7 +18,6 @@ #include -#include #include #include #include @@ -68,12 +67,10 @@ end .req x5 ENTRY(__copy_in_user) -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_enable x3, x4, x6 add end, x0, x2 #include "copy_template.S" -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_disable x3 mov x0, #0 ret ENDPROC(__copy_in_user) diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S index 7a7efe255034..5ae01cbbf333 100644 --- a/arch/arm64/lib/copy_to_user.S +++ b/arch/arm64/lib/copy_to_user.S @@ -16,7 +16,6 @@ #include -#include #include #include #include @@ -66,12 +65,10 @@ end .req x5 ENTRY(__arch_copy_to_user) -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_enable x3, x4, x6 add end, x0, x2 #include "copy_template.S" -ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_ALT_PAN_NOT_UAO, \ - CONFIG_ARM64_PAN) + uaccess_disable x3 mov x0, #0 ret ENDPROC(__arch_copy_to_user)