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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id CFEC1C433EF for ; Fri, 26 Nov 2021 10:12:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=VC5AbQmGCQKa+6j3Pp1rHop+ty/R1DJgtoQ/15THRzI=; b=wNoQnK8a58Bj85 634AxOLsMQcS+qHTOjgE2HDJ9U59+sCpVlpT/oXtOat0oym/KySfohIMrobD/1L87PygaP0pz2PYG o8l8jDSpjqTEfu+ozpVDrm3cUi2iuWeun+G+NSL3XWD6pt2SESCnFuAR/J7Fg78lgY1Rrih+dBW/Y qwSDGqIkVkgVsbq2GZRcJXvhyT5a4V1y28INanm68Erc3Tu8HocqjjanlGcfgqBykT0psTmtiHBvf DbRgNKce+mo1ugafOzE014BFLO5sxrCNqlNON3hRpbhfZ61W90SV3U9xd0JMUB59sMRpFVcr4Og4g 8Yf4Ml/4OPfsExxjJIjg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mqYBv-009tqb-3X; Fri, 26 Nov 2021 10:10:51 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mqYBP-009teZ-Az for linux-arm-kernel@lists.infradead.org; Fri, 26 Nov 2021 10:10:20 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id D657E61038; Fri, 26 Nov 2021 10:10:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637921419; bh=CHdSehNkx/3XP62FvSraIRfzhRGlh+Asz2brpsWBlIk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CugESE75aRJ6hzdkn9ZnIwCHe3cfxJ3hZcgyclDY3391f3BCPCokY6n7h8uDmKbN1 dnOnpjtJr5Q+gzxt8WE6gB3SXBMQ5c4FCIHRuCiTk14jDdyYFD7qeCd17GxctRv4np vAcxmX/7NPgdlyOxdealhw8DPxnPwBWzYGog5iTrO/Ssg0YdmciVh/+hmBZ8+HDYDB EHIw5yaYhZqYTRw/2w1a6/mKR6Iu2zMP3Ex8i/57LFzDu2R2m7xMCXcwIv6u1kfEQB rFCzo48Zd0SHZVO6lxrdvpsHD1vWgZaDf2NjUMaAhbSKjvqkO0JoR2QysfRwdxmiQf 9YDSugzvWtjdQ== From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Cc: Ard Biesheuvel , Russell King , Nicolas Pitre , Arnd Bergmann , Kees Cook , Keith Packard , Linus Walleij , Nick Desaulniers , Tony Lindgren Subject: [RFC PATCH 1/6] ARM: entry: preserve thread_info pointer in switch_to Date: Fri, 26 Nov 2021 11:10:01 +0100 Message-Id: <20211126101006.3410322-2-ardb@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211126101006.3410322-1-ardb@kernel.org> References: <20211126101006.3410322-1-ardb@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2033; h=from:subject; bh=CHdSehNkx/3XP62FvSraIRfzhRGlh+Asz2brpsWBlIk=; b=owEB7QES/pANAwAKAcNPIjmS2Y8kAcsmYgBhoLJ4zjwJeCYOG4/hxX1GCigm5q0AFujCZXSN3kta rk6B/d2JAbMEAAEKAB0WIQT72WJ8QGnJQhU3VynDTyI5ktmPJAUCYaCyeAAKCRDDTyI5ktmPJJ9gC/ 96p9MckXZmLbEfe+gUFNZSk/sy7sQ95a0DlwUHMqtA3jAqwAMquSowo6HNKo9tkynd/Gb40gXDit79 X1yNglNQPHldp0SD+gN9sq95U1PkUM6gFOPMWu7d3pyhfTyqv73E7kDsEMdathDthIwu161u/jWaF0 oGvCmZ6EUA8qDYgGBKQQdKoKSggH7FNV8NoDnNy7+8RBCH7w933AOXolCTPqUTLLTYWaQCj2C9IGKa ViwwvTZslH7TA1/Rc16ehLJoN35B9hbvqWRisb0Aw0jqGp/FFwkOzHO56N4F+7QdhehkinqRPfxtF1 tYkd77Dl9wcIYvkXFqImXCgpL3ruiF9FpsnWBnKPE2r5w97I4lR3Bu4dY4mcqfgvd4/kh8MP1+p4XC 7sPYjg9dZeOI3lxCzLSKfZ8dVJKcfqhM9MaNMDilT0C+nimOV8GHpAcE3dPsv5lJuBkZboMoZElVJ9 Z3BQ4E3zFGSA35roJERmcygR78VUPZnCPCmYdSh2HkWzQ= X-Developer-Key: i=ardb@kernel.org; a=openpgp; fpr=F43D03328115A198C90016883D200E9CA6329909 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211126_021019_454755_8E341A69 X-CRM114-Status: GOOD ( 11.26 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 Tweak the UP stack protector handling code so that the thread info pointer is preserved in R7 until set_current is called. This is needed for a subsequent patch that implements THREAD_INFO_IN_TASK and set_current for UP as well. This also means we will prefer the per-task protector on UP systems that implement the thread ID registers, so tweak the preprocessor conditionals to reflect this. Signed-off-by: Ard Biesheuvel --- arch/arm/kernel/entry-armv.S | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index 5fb7465d14d9..1e26d69ebbf1 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -814,16 +814,16 @@ ENTRY(__switch_to) ldr r6, [r2, #TI_CPU_DOMAIN] #endif switch_tls r1, r4, r5, r3, r7 -#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP) - ldr r7, [r2, #TI_TASK] +#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP) && \ + !defined(CONFIG_STACKPROTECTOR_PER_TASK) + ldr r9, [r2, #TI_TASK] ldr r8, =__stack_chk_guard .if (TSK_STACK_CANARY > IMM12_MASK) - add r7, r7, #TSK_STACK_CANARY & ~IMM12_MASK + add r9, r9, #TSK_STACK_CANARY & ~IMM12_MASK .endif - ldr r7, [r7, #TSK_STACK_CANARY & IMM12_MASK] -#elif defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) - mov r7, r2 @ Preserve 'next' + ldr r9, [r9, #TSK_STACK_CANARY & IMM12_MASK] #endif + mov r7, r2 @ Preserve 'next' #ifdef CONFIG_CPU_USE_DOMAINS mcr p15, 0, r6, c3, c0, 0 @ Set domain register #endif @@ -832,8 +832,9 @@ ENTRY(__switch_to) ldr r0, =thread_notify_head mov r1, #THREAD_NOTIFY_SWITCH bl atomic_notifier_call_chain -#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP) - str r7, [r8] +#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP) && \ + !defined(CONFIG_STACKPROTECTOR_PER_TASK) + str r9, [r8] #endif mov r0, r5 #if !defined(CONFIG_THUMB2_KERNEL) && !defined(CONFIG_VMAP_STACK) -- 2.30.2 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel