From patchwork Thu Feb 1 11:07:34 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 10195307 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 2AFE860567 for ; Thu, 1 Feb 2018 11:08:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0445428980 for ; Thu, 1 Feb 2018 11:08:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EC8152898B; Thu, 1 Feb 2018 11:08:55 +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=-4.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 0BCE228980 for ; Thu, 1 Feb 2018 11:08:52 +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=PITonHehGitP9WM5TzQFfpyY/nH9pIblHLr5uYOpdRo=; b=fVItdbXPaEmkvuj+J6hvVB7Txq 4KsnwwMeY0ySE0WbwWdYPgbR7dnVCU+7D+84FcxJvL8nOwx4l8zvJp7uqvgub4vyN35HiOTW8zrCf a+AbW+6JDPLnS+BraMMN7VQpq3ZNepnIGcZu2JbnMmBSOkeFt9m5Ol3EJ0/uF380xKY/4Xvn0n7ZX GZS8G0dV1ELNd2FvOit6crwYXu1MczSaqa70UsLrrRsKEHV9ssYg+8qsFoQHFdyfe+Bg+9znh41iQ /HoRgEg5TBqLDcYul2ax3xcLppqcNWN8aDxu2hG9JAx6CQ5R7MUd+Mvr6pP/DjpSenWSYDx4CffhX Ph83dAOg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.89 #1 (Red Hat Linux)) id 1ehCja-0006Ak-IG; Thu, 01 Feb 2018 11:08:50 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.89 #1 (Red Hat Linux)) id 1ehCj2-0005eC-UO for linux-arm-kernel@lists.infradead.org; Thu, 01 Feb 2018 11:08:24 +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 137F51596; Thu, 1 Feb 2018 03:08:11 -0800 (PST) Received: from approximate.cambridge.arm.com (approximate.cambridge.arm.com [10.1.207.62]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DF09D3F25C; Thu, 1 Feb 2018 03:08:08 -0800 (PST) From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v4 2/6] arm: Invalidate BTB on prefetch abort outside of user mapping on Cortex A8, A9, A12 and A17 Date: Thu, 1 Feb 2018 11:07:34 +0000 Message-Id: <20180201110738.5421-3-marc.zyngier@arm.com> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20180201110738.5421-1-marc.zyngier@arm.com> References: <20180201110738.5421-1-marc.zyngier@arm.com> 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: Nishanth Menon , Florian Fainelli , Russell King , Ard Biesheuvel , Tony Lindgren , Andre Przywara , Will Deacon , Fabio Estevam , Catalin Marinas , Robin Murphy , Christoffer Dall 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 In order to prevent aliasing attacks on the branch predictor, invalidate the BTB on CPUs that are known to be affected when taking a prefetch abort on a address that is outside of a user task limit. Signed-off-by: Marc Zyngier --- arch/arm/include/asm/cp15.h | 2 ++ arch/arm/mm/fault.c | 25 ++++++++++++++++ arch/arm/mm/fsr-2level.c | 4 +-- arch/arm/mm/fsr-3level.c | 69 +++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 98 insertions(+), 2 deletions(-) diff --git a/arch/arm/include/asm/cp15.h b/arch/arm/include/asm/cp15.h index 4c9fa72b59f5..9e900ae855aa 100644 --- a/arch/arm/include/asm/cp15.h +++ b/arch/arm/include/asm/cp15.h @@ -65,6 +65,8 @@ #define __write_sysreg(v, r, w, c, t) asm volatile(w " " c : : "r" ((t)(v))) #define write_sysreg(v, ...) __write_sysreg(v, __VA_ARGS__) +#define BPIALL __ACCESS_CP15(c7, 0, c5, 6) + extern unsigned long cr_alignment; /* defined in entry-armv.S */ static inline unsigned long get_cr(void) diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index 42f585379e19..2f945c994e25 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -21,6 +21,7 @@ #include #include +#include #include #include #include @@ -396,12 +397,36 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) __do_kernel_fault(mm, addr, fsr, regs); return 0; } + +static int __maybe_unused +do_pabt_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) +{ +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR + if (addr > TASK_SIZE) { + switch (read_cpuid_part()) { + case ARM_CPU_PART_CORTEX_A8: + case ARM_CPU_PART_CORTEX_A9: + case ARM_CPU_PART_CORTEX_A12: + case ARM_CPU_PART_CORTEX_A17: + write_sysreg(0, BPIALL); + break; + } + } +#endif + return do_page_fault(addr, fsr, regs); +} #else /* CONFIG_MMU */ static int do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) { return 0; } + +static int +do_pabt_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) +{ + return 0; +} #endif /* CONFIG_MMU */ /* diff --git a/arch/arm/mm/fsr-2level.c b/arch/arm/mm/fsr-2level.c index f2be95197265..ca07f72d8624 100644 --- a/arch/arm/mm/fsr-2level.c +++ b/arch/arm/mm/fsr-2level.c @@ -51,7 +51,7 @@ static struct fsr_info ifsr_info[] = { { do_bad, SIGBUS, 0, "unknown 4" }, { do_translation_fault, SIGSEGV, SEGV_MAPERR, "section translation fault" }, { do_bad, SIGSEGV, SEGV_ACCERR, "page access flag fault" }, - { do_page_fault, SIGSEGV, SEGV_MAPERR, "page translation fault" }, + { do_pabt_page_fault, SIGSEGV, SEGV_MAPERR, "page translation fault" }, { do_bad, SIGBUS, 0, "external abort on non-linefetch" }, { do_bad, SIGSEGV, SEGV_ACCERR, "section domain fault" }, { do_bad, SIGBUS, 0, "unknown 10" }, @@ -59,7 +59,7 @@ static struct fsr_info ifsr_info[] = { { do_bad, SIGBUS, 0, "external abort on translation" }, { do_sect_fault, SIGSEGV, SEGV_ACCERR, "section permission fault" }, { do_bad, SIGBUS, 0, "external abort on translation" }, - { do_page_fault, SIGSEGV, SEGV_ACCERR, "page permission fault" }, + { do_pabt_page_fault, SIGSEGV, SEGV_ACCERR, "page permission fault" }, { do_bad, SIGBUS, 0, "unknown 16" }, { do_bad, SIGBUS, 0, "unknown 17" }, { do_bad, SIGBUS, 0, "unknown 18" }, diff --git a/arch/arm/mm/fsr-3level.c b/arch/arm/mm/fsr-3level.c index d0ae2963656a..329cf7c2d811 100644 --- a/arch/arm/mm/fsr-3level.c +++ b/arch/arm/mm/fsr-3level.c @@ -66,4 +66,73 @@ static struct fsr_info fsr_info[] = { { do_bad, SIGBUS, 0, "unknown 63" }, }; +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR +static struct fsr_info ifsr_info[] = { + { do_bad, SIGBUS, 0, "unknown 0" }, + { do_bad, SIGBUS, 0, "unknown 1" }, + { do_bad, SIGBUS, 0, "unknown 2" }, + { do_bad, SIGBUS, 0, "unknown 3" }, + { do_bad, SIGBUS, 0, "reserved translation fault" }, + { do_translation_fault, SIGSEGV, SEGV_MAPERR, "level 1 translation fault" }, + { do_translation_fault, SIGSEGV, SEGV_MAPERR, "level 2 translation fault" }, + { do_pabt_page_fault, SIGSEGV, SEGV_MAPERR, "level 3 translation fault" }, + { do_bad, SIGBUS, 0, "reserved access flag fault" }, + { do_bad, SIGSEGV, SEGV_ACCERR, "level 1 access flag fault" }, + { do_pabt_page_fault, SIGSEGV, SEGV_ACCERR, "level 2 access flag fault" }, + { do_pabt_page_fault, SIGSEGV, SEGV_ACCERR, "level 3 access flag fault" }, + { do_bad, SIGBUS, 0, "reserved permission fault" }, + { do_bad, SIGSEGV, SEGV_ACCERR, "level 1 permission fault" }, + { do_pabt_page_fault, SIGSEGV, SEGV_ACCERR, "level 2 permission fault" }, + { do_pabt_page_fault, SIGSEGV, SEGV_ACCERR, "level 3 permission fault" }, + { do_bad, SIGBUS, 0, "synchronous external abort" }, + { do_bad, SIGBUS, 0, "asynchronous external abort" }, + { do_bad, SIGBUS, 0, "unknown 18" }, + { do_bad, SIGBUS, 0, "unknown 19" }, + { do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" }, + { do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" }, + { do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" }, + { do_bad, SIGBUS, 0, "synchronous abort (translation table walk)" }, + { do_bad, SIGBUS, 0, "synchronous parity error" }, + { do_bad, SIGBUS, 0, "asynchronous parity error" }, + { do_bad, SIGBUS, 0, "unknown 26" }, + { do_bad, SIGBUS, 0, "unknown 27" }, + { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" }, + { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" }, + { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" }, + { do_bad, SIGBUS, 0, "synchronous parity error (translation table walk" }, + { do_bad, SIGBUS, 0, "unknown 32" }, + { do_bad, SIGBUS, BUS_ADRALN, "alignment fault" }, + { do_bad, SIGBUS, 0, "debug event" }, + { do_bad, SIGBUS, 0, "unknown 35" }, + { do_bad, SIGBUS, 0, "unknown 36" }, + { do_bad, SIGBUS, 0, "unknown 37" }, + { do_bad, SIGBUS, 0, "unknown 38" }, + { do_bad, SIGBUS, 0, "unknown 39" }, + { do_bad, SIGBUS, 0, "unknown 40" }, + { do_bad, SIGBUS, 0, "unknown 41" }, + { do_bad, SIGBUS, 0, "unknown 42" }, + { do_bad, SIGBUS, 0, "unknown 43" }, + { do_bad, SIGBUS, 0, "unknown 44" }, + { do_bad, SIGBUS, 0, "unknown 45" }, + { do_bad, SIGBUS, 0, "unknown 46" }, + { do_bad, SIGBUS, 0, "unknown 47" }, + { do_bad, SIGBUS, 0, "unknown 48" }, + { do_bad, SIGBUS, 0, "unknown 49" }, + { do_bad, SIGBUS, 0, "unknown 50" }, + { do_bad, SIGBUS, 0, "unknown 51" }, + { do_bad, SIGBUS, 0, "implementation fault (lockdown abort)" }, + { do_bad, SIGBUS, 0, "unknown 53" }, + { do_bad, SIGBUS, 0, "unknown 54" }, + { do_bad, SIGBUS, 0, "unknown 55" }, + { do_bad, SIGBUS, 0, "unknown 56" }, + { do_bad, SIGBUS, 0, "unknown 57" }, + { do_bad, SIGBUS, 0, "implementation fault (coprocessor abort)" }, + { do_bad, SIGBUS, 0, "unknown 59" }, + { do_bad, SIGBUS, 0, "unknown 60" }, + { do_bad, SIGBUS, 0, "unknown 61" }, + { do_bad, SIGBUS, 0, "unknown 62" }, + { do_bad, SIGBUS, 0, "unknown 63" }, +}; +#else #define ifsr_info fsr_info +#endif