From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D56EEC433E1 for ; Tue, 18 Aug 2020 07:13:16 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6AEB820658 for ; Tue, 18 Aug 2020 07:13:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="DVQFGQ4F" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6AEB820658 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.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=HeYkg9I/dH8PcLS3KnpvI7FOfeVx8sBEzB+tPMlB3SM=; b=DVQFGQ4FEKGwZ3wWmdodsTo+Df l+4enX/x7Qj6Vrgdeub7cfidOazDgEJo/YrouZOx3LArBgs88ItzNkrWCg9RGOAeAwfFeU/j+nPsh HBPenWZR6O2RLM2LN8IgjQuziMtcZnpkA14GNkce4vmc9aT4Be8kwuTa3gJ1oWgn3IXj9c0X0325i aE0d4rm8maIc6UZpNlW0jBrJ/xlw0FciilS6xNvcul/9/5sNCMJD7FEORZiUtXwfA+4cnrgYNwEcX JQL2gnpeM6iHVnRrSq2gdHTQypYsbImBs0eFdgj4qt8Oz1NF8yYggNVIoPb3iqnSyY5BQBqmVXtGi E2WbpxEw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7vmT-00012g-Op; Tue, 18 Aug 2020 07:11:37 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k7vmQ-00011N-1T for linux-arm-kernel@lists.infradead.org; Tue, 18 Aug 2020 07:11:35 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C8307101E; Tue, 18 Aug 2020 00:11:31 -0700 (PDT) Received: from a075553-lin.blr.arm.com (a075553-lin.blr.arm.com [10.162.17.24]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 9F16E3F66B; Tue, 18 Aug 2020 00:11:28 -0700 (PDT) From: Amit Daniel Kachhap To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v5 1/6] arm64: kprobe: add checks for ARMv8.3-PAuth combined instructions Date: Tue, 18 Aug 2020 12:41:06 +0530 Message-Id: <1597734671-23407-2-git-send-email-amit.kachhap@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1597734671-23407-1-git-send-email-amit.kachhap@arm.com> References: <1597734671-23407-1-git-send-email-amit.kachhap@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200818_031134_181280_96E8DECB X-CRM114-Status: GOOD ( 12.88 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Kees Cook , Suzuki K Poulose , Catalin Marinas , Mark Brown , James Morse , Amit Daniel Kachhap , Vincenzo Frascino , Will Deacon , Dave Martin MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Currently the ARMv8.3-PAuth combined branch instructions (braa, retaa etc.) are not simulated. However the uprobe of such instructions leads to kernel warnings in a loop as they are not explicitly checked. This is fixed by adding definitions of all such instructions and rejecting their probes. Warning log: WARNING: CPU: 5 PID: 249 at arch/arm64/kernel/probes/uprobes.c:182 uprobe_single_step_handler+0x34/0x50 Modules linked in: CPU: 5 PID: 249 Comm: func Tainted: G W 5.8.0-rc4-00005-ge658591d66d1-dirty #160 Hardware name: Foundation-v8A (DT) pstate: 204003c9 (nzCv DAIF +PAN -UAO BTYPE=--) pc : uprobe_single_step_handler+0x34/0x50 lr : single_step_handler+0x70/0xf8 sp : ffff800012afbe30 x29: ffff800012afbe30 x28: ffff000879f00ec0 x27: 0000000000000000 x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 x23: 0000000060001000 x22: 00000000cb000022 x21: ffff800011fc5a68 x20: ffff800012afbec0 x19: ffff800011fc86c0 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000000000 x9 : ffff800010085d50 x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffff800011fba9c0 x5 : ffff800011fba000 x4 : ffff800012283070 x3 : ffff8000100a78e0 x2 : 00000000004005f0 x1 : 0000fffffffff008 x0 : ffff800012afbec0 Call trace: uprobe_single_step_handler+0x34/0x50 single_step_handler+0x70/0xf8 do_debug_exception+0xb8/0x130 el0_sync_handler+0x7c/0x188 el0_sync+0x158/0x180 Fixes: 74afda4016a7 ("arm64: compile the kernel with ptrauth return address signing") Fixes: 04ca3204fa09 ("arm64: enable pointer authentication") Signed-off-by: Amit Daniel Kachhap --- Changes since v4: * New patch. arch/arm64/include/asm/insn.h | 12 ++++++++++++ arch/arm64/kernel/insn.c | 14 ++++++++++++-- arch/arm64/kernel/probes/decode-insn.c | 4 +++- 3 files changed, 27 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h index 0bc46149e491..324234068fee 100644 --- a/arch/arm64/include/asm/insn.h +++ b/arch/arm64/include/asm/insn.h @@ -359,9 +359,21 @@ __AARCH64_INSN_FUNCS(brk, 0xFFE0001F, 0xD4200000) __AARCH64_INSN_FUNCS(exception, 0xFF000000, 0xD4000000) __AARCH64_INSN_FUNCS(hint, 0xFFFFF01F, 0xD503201F) __AARCH64_INSN_FUNCS(br, 0xFFFFFC1F, 0xD61F0000) +__AARCH64_INSN_FUNCS(braaz, 0xFFFFFC1F, 0xD61F081F) +__AARCH64_INSN_FUNCS(brabz, 0xFFFFFC1F, 0xD61F0C1F) +__AARCH64_INSN_FUNCS(braa, 0xFFFFFC00, 0xD71F0800) +__AARCH64_INSN_FUNCS(brab, 0xFFFFFC00, 0xD71F0C00) __AARCH64_INSN_FUNCS(blr, 0xFFFFFC1F, 0xD63F0000) +__AARCH64_INSN_FUNCS(blraaz, 0xFFFFFC1F, 0xD63F081F) +__AARCH64_INSN_FUNCS(blrabz, 0xFFFFFC1F, 0xD63F0C1F) +__AARCH64_INSN_FUNCS(blraa, 0xFFFFFC00, 0xD73F0800) +__AARCH64_INSN_FUNCS(blrab, 0xFFFFFC00, 0xD73F0C00) __AARCH64_INSN_FUNCS(ret, 0xFFFFFC1F, 0xD65F0000) +__AARCH64_INSN_FUNCS(retaa, 0xFFFFFFFF, 0xD65F0BFF) +__AARCH64_INSN_FUNCS(retab, 0xFFFFFFFF, 0xD65F0FFF) __AARCH64_INSN_FUNCS(eret, 0xFFFFFFFF, 0xD69F03E0) +__AARCH64_INSN_FUNCS(eretaa, 0xFFFFFFFF, 0xD69F0BFF) +__AARCH64_INSN_FUNCS(eretab, 0xFFFFFFFF, 0xD69F0FFF) __AARCH64_INSN_FUNCS(mrs, 0xFFF00000, 0xD5300000) __AARCH64_INSN_FUNCS(msr_imm, 0xFFF8F01F, 0xD500401F) __AARCH64_INSN_FUNCS(msr_reg, 0xFFF00000, 0xD5100000) diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c index a107375005bc..27d5a52d5058 100644 --- a/arch/arm64/kernel/insn.c +++ b/arch/arm64/kernel/insn.c @@ -176,7 +176,7 @@ bool __kprobes aarch64_insn_uses_literal(u32 insn) bool __kprobes aarch64_insn_is_branch(u32 insn) { - /* b, bl, cb*, tb*, b.cond, br, blr */ + /* b, bl, cb*, tb*, ret*, b.cond, br*, blr* */ return aarch64_insn_is_b(insn) || aarch64_insn_is_bl(insn) || @@ -185,9 +185,19 @@ bool __kprobes aarch64_insn_is_branch(u32 insn) aarch64_insn_is_tbz(insn) || aarch64_insn_is_tbnz(insn) || aarch64_insn_is_ret(insn) || + aarch64_insn_is_retaa(insn) || + aarch64_insn_is_retab(insn) || aarch64_insn_is_br(insn) || aarch64_insn_is_blr(insn) || - aarch64_insn_is_bcond(insn); + aarch64_insn_is_bcond(insn) || + aarch64_insn_is_braaz(insn) || + aarch64_insn_is_brabz(insn) || + aarch64_insn_is_braa(insn) || + aarch64_insn_is_brab(insn) || + aarch64_insn_is_blraaz(insn) || + aarch64_insn_is_blrabz(insn) || + aarch64_insn_is_blraa(insn) || + aarch64_insn_is_blrab(insn); } int __kprobes aarch64_insn_patch_text_nosync(void *addr, u32 insn) diff --git a/arch/arm64/kernel/probes/decode-insn.c b/arch/arm64/kernel/probes/decode-insn.c index 263d5fba4c8a..f9eb8210d6d3 100644 --- a/arch/arm64/kernel/probes/decode-insn.c +++ b/arch/arm64/kernel/probes/decode-insn.c @@ -29,7 +29,9 @@ static bool __kprobes aarch64_insn_is_steppable(u32 insn) aarch64_insn_is_msr_imm(insn) || aarch64_insn_is_msr_reg(insn) || aarch64_insn_is_exception(insn) || - aarch64_insn_is_eret(insn)) + aarch64_insn_is_eret(insn) || + aarch64_insn_is_eretaa(insn) || + aarch64_insn_is_eretab(insn)) return false; /* -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel