From patchwork Fri Oct 30 15:49:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 11870163 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 5F23FC00A89 for ; Fri, 30 Oct 2020 15:51:25 +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 D6DA2206E9 for ; Fri, 30 Oct 2020 15:51:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="ULHTdoFw"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="WVmWqQwG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D6DA2206E9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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=eehAEu1PKXz3Lhb2lbAw7Dj23QxbUBpRkWd2wIETbO4=; b=ULHTdoFwLRYCvb06dcW09eoRL hMfPGTEfVKnpt4eau57WCKfCChtEMToykPq003Q++tnEcXDJK9SfwDfESzwmB4u78nLfI4GKxRZZ0 EyrqF8j9SkqQ/sgT+FcNTP1pf2rxwo449ZxpKph2Qb5VoTo9t2oF2nN2KA99BynDZ0rz3cqCZvxRt Zf8761SMxaRsKabW3as2qZkWCZ+a4KqSuSWumU+IBAcm1hIYPUvUnIdBaWRTV+xrn37BO1snfXJHr 1xX7oUhGLfdSPJ95C7SOS3KsjL9HIdF+Li4QmmN7523HfKRQFi5oU2BS7pLkGAXqcvWcuvtBWxJS4 EXr67x+yA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWek-0002tc-Ce; Fri, 30 Oct 2020 15:49:34 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWeg-0002sX-Tv for linux-arm-kernel@lists.infradead.org; Fri, 30 Oct 2020 15:49:31 +0000 Received: from localhost.localdomain (HSI-KBW-46-223-126-90.hsi.kabel-badenwuerttemberg.de [46.223.126.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id ED397206E9; Fri, 30 Oct 2020 15:49:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604072969; bh=xH/xlh89YROcQ6IGanzE2IUwe7x9ABvjpXSH43dVrJE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WVmWqQwGHaS4dTDzDIyxXEX9rwVMnmELKiEcch4wuAWUu8jAMUxoLWiZkQfs4syTF F84Lc34G02PqLbS7gUO690oFismOg2pygTQWoC8GmN6c7zobjVWdHA3RXEXTJh299w R7/iMgOB2iHrCSL1nCvDdOuXub2rAYRb+K9ubr3M= From: Arnd Bergmann To: Russell King , Christoph Hellwig Subject: [PATCH 1/9] mm/maccess: fix unaligned copy_{from,to}_kernel_nofault Date: Fri, 30 Oct 2020 16:49:11 +0100 Message-Id: <20201030154919.1246645-1-arnd@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201030154519.1245983-1-arnd@kernel.org> References: <20201030154519.1245983-1-arnd@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201030_114931_073665_6735DF8A X-CRM114-Status: GOOD ( 16.17 ) 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: linux-arch@vger.kernel.org, arnd@arndb.de, linus.walleij@linaro.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Arnd Bergmann On machines such as ARMv5 that trap unaligned accesses, these two functions can be slow when each access needs to be emulated, or they might not work at all. Change them so that each loop is only used when both the src and dst pointers are naturally aligned. Reviewed-by: Christoph Hellwig Signed-off-by: Arnd Bergmann Reviewed-by: Linus Walleij --- mm/maccess.c | 28 ++++++++++++++++++++++------ 1 file changed, 22 insertions(+), 6 deletions(-) diff --git a/mm/maccess.c b/mm/maccess.c index 3bd70405f2d8..d3f1a1f0b1c1 100644 --- a/mm/maccess.c +++ b/mm/maccess.c @@ -24,13 +24,21 @@ bool __weak copy_from_kernel_nofault_allowed(const void *unsafe_src, long copy_from_kernel_nofault(void *dst, const void *src, size_t size) { + unsigned long align = 0; + + if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) + align = (unsigned long)dst | (unsigned long)src; + if (!copy_from_kernel_nofault_allowed(src, size)) return -ERANGE; pagefault_disable(); - copy_from_kernel_nofault_loop(dst, src, size, u64, Efault); - copy_from_kernel_nofault_loop(dst, src, size, u32, Efault); - copy_from_kernel_nofault_loop(dst, src, size, u16, Efault); + if (!(align & 7)) + copy_from_kernel_nofault_loop(dst, src, size, u64, Efault); + if (!(align & 3)) + copy_from_kernel_nofault_loop(dst, src, size, u32, Efault); + if (!(align & 1)) + copy_from_kernel_nofault_loop(dst, src, size, u16, Efault); copy_from_kernel_nofault_loop(dst, src, size, u8, Efault); pagefault_enable(); return 0; @@ -50,10 +58,18 @@ EXPORT_SYMBOL_GPL(copy_from_kernel_nofault); long copy_to_kernel_nofault(void *dst, const void *src, size_t size) { + unsigned long align = 0; + + if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) + align = (unsigned long)dst | (unsigned long)src; + pagefault_disable(); - copy_to_kernel_nofault_loop(dst, src, size, u64, Efault); - copy_to_kernel_nofault_loop(dst, src, size, u32, Efault); - copy_to_kernel_nofault_loop(dst, src, size, u16, Efault); + if (!(align & 7)) + copy_to_kernel_nofault_loop(dst, src, size, u64, Efault); + if (!(align & 3)) + copy_to_kernel_nofault_loop(dst, src, size, u32, Efault); + if (!(align & 1)) + copy_to_kernel_nofault_loop(dst, src, size, u16, Efault); copy_to_kernel_nofault_loop(dst, src, size, u8, Efault); pagefault_enable(); return 0; From patchwork Fri Oct 30 15:49:12 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 11870161 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 069FDC00A89 for ; Fri, 30 Oct 2020 15:50:47 +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 82B15221EB for ; Fri, 30 Oct 2020 15:50:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="k1tBs1Dq"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="TWyfwhH4" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 82B15221EB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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=IL2WxOgTtzRCivicAX5S8RU4ukAudKWB+KMhYLMsJz0=; b=k1tBs1DqDpAkqKp8e4M13dW5u bdJwyrAKJFGctTjkYeg4S3SdPiWCp57ft6LSbnS1JBEnSSEHAP5GHpL1Hy/Aag7ZVuxhRUspL/OLm cXBhsXJDLAR6HEAiWF/N/QieX5W5ZJFv+hbtCiFUlloyaxbb1T65m/fLCjaem6yMemv9MGNk6amJ2 UcqjBX2YqQa1E06pcYnesBHmZB091srl3aT3qJCFcCiTX9Uk0PQTVRHSvB7Tt4KmuIAZ/+JB81F5v UbtMQL7ZgiDc9pUddjJKRP55vIZMdKIMSElDWB3h/qY+6YYyBPfN+nHi61ArZlQ72Y4YbNNsTzshZ 4aTj5SiVw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWf5-000318-Q4; Fri, 30 Oct 2020 15:49:55 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWei-0002tO-S7 for linux-arm-kernel@lists.infradead.org; Fri, 30 Oct 2020 15:49:38 +0000 Received: from localhost.localdomain (HSI-KBW-46-223-126-90.hsi.kabel-badenwuerttemberg.de [46.223.126.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 45B6C2151B; Fri, 30 Oct 2020 15:49:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604072972; bh=ZWVfnKETIZSkSXx6wtt9uwQPqWB73y+8PUTcomvoy2w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TWyfwhH4qhKP35A1ntbbH2uTPQAKolFdHFHrtSWwJy5Sq5MvZ555anM/3vysGQt3y VQVFD3UKiR9sA0ZvC/Z2NGFLAwjkgRWm6gMwYLIrEkgPnGIiqou5iSFnPMElVNJU08 Q5LxJVIxJgvA6T5x1TmH6oh+G31HTu67VEszV24o= From: Arnd Bergmann To: Russell King , Christoph Hellwig Subject: [PATCH 2/9] ARM: traps: use get_kernel_nofault instead of set_fs() Date: Fri, 30 Oct 2020 16:49:12 +0100 Message-Id: <20201030154919.1246645-2-arnd@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201030154919.1246645-1-arnd@kernel.org> References: <20201030154519.1245983-1-arnd@kernel.org> <20201030154919.1246645-1-arnd@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201030_114933_620282_E9403BBB X-CRM114-Status: GOOD ( 21.57 ) 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: linux-arch@vger.kernel.org, arnd@arndb.de, linus.walleij@linaro.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Arnd Bergmann ARM uses set_fs() and __get_user() to allow the stack dumping code to access possibly invalid pointers carefully. These can be changed to the simpler get_kernel_nofault(), and allow the eventual removal of set_fs(). dump_instr() will print either kernel or user space pointers, depending on how it was called. For dump_mem(), I assume we are only interested in kernel pointers, and the only time that this is called with user_mode(regs)==true is when the regs themselves are unreliable as a result of the condition that caused the trap. Reviewed-by: Christoph Hellwig Signed-off-by: Arnd Bergmann Reviewed-by: Linus Walleij --- arch/arm/kernel/traps.c | 47 ++++++++++++++--------------------------- 1 file changed, 16 insertions(+), 31 deletions(-) diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 17d5a785df28..c3964a283b63 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -122,17 +122,8 @@ static void dump_mem(const char *lvl, const char *str, unsigned long bottom, unsigned long top) { unsigned long first; - mm_segment_t fs; int i; - /* - * We need to switch to kernel mode so that we can use __get_user - * to safely read from kernel space. Note that we now dump the - * code first, just in case the backtrace kills us. - */ - fs = get_fs(); - set_fs(KERNEL_DS); - printk("%s%s(0x%08lx to 0x%08lx)\n", lvl, str, bottom, top); for (first = bottom & ~31; first < top; first += 32) { @@ -145,7 +136,7 @@ static void dump_mem(const char *lvl, const char *str, unsigned long bottom, for (p = first, i = 0; i < 8 && p < top; i++, p += 4) { if (p >= bottom && p < top) { unsigned long val; - if (__get_user(val, (unsigned long *)p) == 0) + if (get_kernel_nofault(val, (unsigned long *)p)) sprintf(str + i * 9, " %08lx", val); else sprintf(str + i * 9, " ????????"); @@ -153,11 +144,9 @@ static void dump_mem(const char *lvl, const char *str, unsigned long bottom, } printk("%s%04lx:%s\n", lvl, first & 0xffff, str); } - - set_fs(fs); } -static void __dump_instr(const char *lvl, struct pt_regs *regs) +static void dump_instr(const char *lvl, struct pt_regs *regs) { unsigned long addr = instruction_pointer(regs); const int thumb = thumb_mode(regs); @@ -173,10 +162,20 @@ static void __dump_instr(const char *lvl, struct pt_regs *regs) for (i = -4; i < 1 + !!thumb; i++) { unsigned int val, bad; - if (thumb) - bad = get_user(val, &((u16 *)addr)[i]); - else - bad = get_user(val, &((u32 *)addr)[i]); + if (!user_mode(regs)) { + if (thumb) { + u16 val16; + bad = get_kernel_nofault(val16, &((u16 *)addr)[i]); + val = val16; + } else { + bad = get_kernel_nofault(val, &((u32 *)addr)[i]); + } + } else { + if (thumb) + bad = get_user(val, &((u16 *)addr)[i]); + else + bad = get_user(val, &((u32 *)addr)[i]); + } if (!bad) p += sprintf(p, i == 0 ? "(%0*x) " : "%0*x ", @@ -189,20 +188,6 @@ static void __dump_instr(const char *lvl, struct pt_regs *regs) printk("%sCode: %s\n", lvl, str); } -static void dump_instr(const char *lvl, struct pt_regs *regs) -{ - mm_segment_t fs; - - if (!user_mode(regs)) { - fs = get_fs(); - set_fs(KERNEL_DS); - __dump_instr(lvl, regs); - set_fs(fs); - } else { - __dump_instr(lvl, regs); - } -} - #ifdef CONFIG_ARM_UNWIND static inline void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, const char *loglvl) From patchwork Fri Oct 30 15:49:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 11870167 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 BB78BC00A89 for ; Fri, 30 Oct 2020 15:52:06 +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 3652A206E9 for ; Fri, 30 Oct 2020 15:52:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="KKBb93Wt"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="rHMmLQWj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3652A206E9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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=GzjMJM4crfwGMCqcpMDA7p9GX5Yrm/BUNIFK10zO6Rg=; b=KKBb93WtyvMN0qTDgkiIErzW6 UxK/TRc2rTcvrBCS5aQRoVcVC2DgVN3bBbMIY7xzlJftoK2d3DlyUW1o5CUXnIgr3gbzaUIJz843G yoUmJCeV5/wHVBcHbqDG4owV4wFTg+s1cB1Nds9zlKPkPBvesVrv2MzkjQiEt/8XZzU1bOH+ZzMcY sTg6urSJjGPS9MO60ta4sGXLFmez7J8/Qa29xGYoHizZOqOZlMlHgybrMxBi2caidsZyjWhCpNhgR v4D75j2UIB+XWu2Fy7BroyPtAUN8g6y3mKtEC0VEold72akYD3RU+bRNM+SCCqAquaVg0n0No6dgg +tJ4n6zKA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWfT-0003C9-Aw; Fri, 30 Oct 2020 15:50:19 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWel-0002uT-IS for linux-arm-kernel@lists.infradead.org; Fri, 30 Oct 2020 15:49:39 +0000 Received: from localhost.localdomain (HSI-KBW-46-223-126-90.hsi.kabel-badenwuerttemberg.de [46.223.126.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 95439221EB; Fri, 30 Oct 2020 15:49:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604072974; bh=V6qzY14LfJ5Qyf+Zp/oXQxezqCq4VbzoDYPwNxOKOhw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rHMmLQWj/hrKi5keJjlqsxQMjXZrNmlZKbjy2paFODhj+RqM7NouoGE8VKn2UoUkM rESg3IOM/PSjlrHek6TbvICXdfd2VegMQXfqY/RnZzQhXYViEg8hDoitR7Ygtfhc1T mukGs/RapqPzH4p9SMRx1iDhzwju+1vManV9j6Zs= From: Arnd Bergmann To: Russell King , Christoph Hellwig Subject: [PATCH 3/9] ARM: oabi-compat: add epoll_pwait handler Date: Fri, 30 Oct 2020 16:49:13 +0100 Message-Id: <20201030154919.1246645-3-arnd@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201030154919.1246645-1-arnd@kernel.org> References: <20201030154519.1245983-1-arnd@kernel.org> <20201030154919.1246645-1-arnd@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201030_114935_861881_9C3417AC X-CRM114-Status: GOOD ( 18.64 ) 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: linux-arch@vger.kernel.org, arnd@arndb.de, linus.walleij@linaro.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Arnd Bergmann The epoll_wait() syscall has a special version for OABI compat mode to convert the arguments to the EABI structure layout of the kernel. However, the later epoll_pwait() syscall was added in arch/arm in linux-2.6.32 without this conversion. Use the same kind of handler for both. Fixes: 369842658a36 ("ARM: 5677/1: ARM support for TIF_RESTORE_SIGMASK/pselect6/ppoll/epoll_pwait") Cc: stable@vger.kernel.org Reviewed-by: Christoph Hellwig Signed-off-by: Arnd Bergmann --- arch/arm/kernel/sys_oabi-compat.c | 37 ++++++++++++++++++++++++++++--- arch/arm/tools/syscall.tbl | 2 +- 2 files changed, 35 insertions(+), 4 deletions(-) diff --git a/arch/arm/kernel/sys_oabi-compat.c b/arch/arm/kernel/sys_oabi-compat.c index 0203e545bbc8..a2b1ae01e5bf 100644 --- a/arch/arm/kernel/sys_oabi-compat.c +++ b/arch/arm/kernel/sys_oabi-compat.c @@ -264,9 +264,8 @@ asmlinkage long sys_oabi_epoll_ctl(int epfd, int op, int fd, return do_epoll_ctl(epfd, op, fd, &kernel, false); } -asmlinkage long sys_oabi_epoll_wait(int epfd, - struct oabi_epoll_event __user *events, - int maxevents, int timeout) +static long do_oabi_epoll_wait(int epfd, struct oabi_epoll_event __user *events, + int maxevents, int timeout) { struct epoll_event *kbuf; struct oabi_epoll_event e; @@ -299,6 +298,38 @@ asmlinkage long sys_oabi_epoll_wait(int epfd, return err ? -EFAULT : ret; } +SYSCALL_DEFINE4(oabi_epoll_wait, int, epfd, + struct oabi_epoll_event __user *, events, + int, maxevents, int, timeout) +{ + return do_oabi_epoll_wait(epfd, events, maxevents, timeout); +} + +/* + * Implement the event wait interface for the eventpoll file. It is the kernel + * part of the user space epoll_pwait(2). + */ +SYSCALL_DEFINE6(oabi_epoll_pwait, int, epfd, + struct oabi_epoll_event __user *, events, int, maxevents, + int, timeout, const sigset_t __user *, sigmask, + size_t, sigsetsize) +{ + int error; + + /* + * If the caller wants a certain signal mask to be set during the wait, + * we apply it here. + */ + error = set_user_sigmask(sigmask, sigsetsize); + if (error) + return error; + + error = do_oabi_epoll_wait(epfd, events, maxevents, timeout); + restore_saved_sigmask_unless(error == -EINTR); + + return error; +} + struct oabi_sembuf { unsigned short sem_num; short sem_op; diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index d056a548358e..330cf0aa04c4 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -360,7 +360,7 @@ 343 common vmsplice sys_vmsplice 344 common move_pages sys_move_pages 345 common getcpu sys_getcpu -346 common epoll_pwait sys_epoll_pwait +346 common epoll_pwait sys_epoll_pwait sys_oabi_epoll_pwait 347 common kexec_load sys_kexec_load 348 common utimensat sys_utimensat_time32 349 common signalfd sys_signalfd From patchwork Fri Oct 30 15:49:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 11870165 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 521E3C00A89 for ; Fri, 30 Oct 2020 15:51:28 +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 CE6DB20A8B for ; Fri, 30 Oct 2020 15:51:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="hdkn8ply"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="OncIA6fg" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CE6DB20A8B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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=tQMdQqsFy4QAYvLNaJh/l3cnQH3VRJ6OZYWGE7pV29U=; b=hdkn8plypHOYOcyvxe+cQswON WZZj7ToyL4LE1WqA/yDRrVsegy+U6aDnLE49He/6aMvTRZAkOCKv32iqsquCtobd8nBPp3gK6hEHV /vnt7kq+Pn3Bxrjv7iUn+gH0BCrJlepXjZYYAw4GkocKZxvatVw6Uz4CPnTow0Xmo64jj8Geb7uUC 0OfN3nBLFGAmv09fD2E7IIdfS94UacIORvF7E0AaYvaLQxbSYhrwqpI8qUuHL2D+UzXyrT7qVPG3t Ev2HjATUZU1WydTQPNM/YwAmjIF/tUPGv6ZxTrASadokR94nPCmBB3rvBRkUUzfhsiB2n0Rt+2nms WHHBK+umQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWfp-0003Gs-2g; Fri, 30 Oct 2020 15:50:41 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWen-0002vS-Tx for linux-arm-kernel@lists.infradead.org; Fri, 30 Oct 2020 15:49:44 +0000 Received: from localhost.localdomain (HSI-KBW-46-223-126-90.hsi.kabel-badenwuerttemberg.de [46.223.126.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1AF182223F; Fri, 30 Oct 2020 15:49:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604072977; bh=fY6p+lkklIuvlOl6LSOK1NSbGCEH/SLgf43BZ+YXIi4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OncIA6fgT7xFpJo++EiS1WLvS/pajpXd+csgRgpXj9iJfxdcXoVFvkZC2udyZ7Gc0 A7YWdxoVLtkUb/MfCSuNuR2coybydBXmuGgODODKEQw7OYawqvdhClLdjklrO58mlD gWrbJrvaqoWYAbuuzGAp2QfG0RB11vi75z2ReBXs= From: Arnd Bergmann To: Russell King , Christoph Hellwig Subject: [PATCH 4/9] ARM: syscall: always store thread_info->syscall Date: Fri, 30 Oct 2020 16:49:14 +0100 Message-Id: <20201030154919.1246645-4-arnd@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201030154919.1246645-1-arnd@kernel.org> References: <20201030154519.1245983-1-arnd@kernel.org> <20201030154919.1246645-1-arnd@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201030_114938_236364_E0607E7D X-CRM114-Status: GOOD ( 20.99 ) 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: linux-arch@vger.kernel.org, arnd@arndb.de, linus.walleij@linaro.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Arnd Bergmann The system call number is used in a a couple of places, in particular ptrace, seccomp and /proc//syscall. The last one apparently never worked reliably on ARM for tasks that are not currently getting traced. Storing the syscall number in the normal entry path makes it work, as well as allowing us to see if the current system call is for OABI compat mode, which is the next thing I want to hook into. Signed-off-by: Arnd Bergmann --- arch/arm/include/asm/syscall.h | 5 ++++- arch/arm/kernel/asm-offsets.c | 1 + arch/arm/kernel/entry-common.S | 8 ++++++-- arch/arm/kernel/ptrace.c | 9 +++++---- 4 files changed, 16 insertions(+), 7 deletions(-) diff --git a/arch/arm/include/asm/syscall.h b/arch/arm/include/asm/syscall.h index fd02761ba06c..89898497edd6 100644 --- a/arch/arm/include/asm/syscall.h +++ b/arch/arm/include/asm/syscall.h @@ -22,7 +22,10 @@ extern const unsigned long sys_call_table[]; static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs) { - return task_thread_info(task)->syscall; + if (IS_ENABLED(CONFIG_AEABI) && !IS_ENABLED(CONFIG_OABI_COMPAT)) + return task_thread_info(task)->syscall; + + return task_thread_info(task)->syscall & ~__NR_OABI_SYSCALL_BASE; } static inline void syscall_rollback(struct task_struct *task, diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c index a1570c8bab25..97af6735172b 100644 --- a/arch/arm/kernel/asm-offsets.c +++ b/arch/arm/kernel/asm-offsets.c @@ -46,6 +46,7 @@ int main(void) DEFINE(TI_CPU, offsetof(struct thread_info, cpu)); DEFINE(TI_CPU_DOMAIN, offsetof(struct thread_info, cpu_domain)); DEFINE(TI_CPU_SAVE, offsetof(struct thread_info, cpu_context)); + DEFINE(TI_SYSCALL, offsetof(struct thread_info, syscall)); DEFINE(TI_USED_CP, offsetof(struct thread_info, used_cp)); DEFINE(TI_TP_VALUE, offsetof(struct thread_info, tp_value)); DEFINE(TI_FPSTATE, offsetof(struct thread_info, fpstate)); diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 271cb8a1eba1..9a76467bbb47 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -223,6 +223,7 @@ ENTRY(vector_swi) /* saved_psr and saved_pc are now dead */ uaccess_disable tbl + get_thread_info tsk adr tbl, sys_call_table @ load syscall table pointer @@ -234,13 +235,17 @@ ENTRY(vector_swi) * get the old ABI syscall table address. */ bics r10, r10, #0xff000000 + strne r10, [tsk, #TI_SYSCALL] + streq scno, [tsk, #TI_SYSCALL] eorne scno, r10, #__NR_OABI_SYSCALL_BASE ldrne tbl, =sys_oabi_call_table #elif !defined(CONFIG_AEABI) bic scno, scno, #0xff000000 @ mask off SWI op-code + str scno, [tsk, #TI_SYSCALL] eor scno, scno, #__NR_SYSCALL_BASE @ check OS number +#else + str scno, [tsk, #TI_SYSCALL] #endif - get_thread_info tsk /* * Reload the registers that may have been corrupted on entry to * the syscall assembly (by tracing or context tracking.) @@ -285,7 +290,6 @@ ENDPROC(vector_swi) * context switches, and waiting for our parent to respond. */ __sys_trace: - mov r1, scno add r0, sp, #S_OFF bl syscall_trace_enter mov scno, r0 diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c index 2771e682220b..683edb8b627d 100644 --- a/arch/arm/kernel/ptrace.c +++ b/arch/arm/kernel/ptrace.c @@ -25,6 +25,7 @@ #include #include +#include #include #define CREATE_TRACE_POINTS @@ -885,9 +886,9 @@ static void tracehook_report_syscall(struct pt_regs *regs, regs->ARM_ip = ip; } -asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno) +asmlinkage int syscall_trace_enter(struct pt_regs *regs) { - current_thread_info()->syscall = scno; + int scno; if (test_thread_flag(TIF_SYSCALL_TRACE)) tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER); @@ -898,11 +899,11 @@ asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno) return -1; #else /* XXX: remove this once OABI gets fixed */ - secure_computing_strict(current_thread_info()->syscall); + secure_computing_strict(syscall_get_nr(current, regs)); #endif /* Tracer or seccomp may have changed syscall. */ - scno = current_thread_info()->syscall; + scno = syscall_get_nr(current, regs); if (test_thread_flag(TIF_SYSCALL_TRACEPOINT)) trace_sys_enter(regs, scno); From patchwork Fri Oct 30 15:49:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 11870169 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 A02FBC00A89 for ; Fri, 30 Oct 2020 15:51:52 +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 294DB206E9 for ; Fri, 30 Oct 2020 15:51:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="WFjCgVRm"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="XqTBWM/a" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 294DB206E9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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=Loo4G4Nb/Q7q6cJAvYgpT20hVh5dt0jvq7gKBv/JsMo=; b=WFjCgVRmvkRFSedjy4FCaNiPy HakNknsJJORft5eb5CuCSY3f25gOrisD96Z7iJYfcfRoGWdnvG5WkyGFA+qzdRfSwuWDuinXzjfAM BpI2KalKVxAHrprgJUU0Z3SWj2iOuc1hvFv+hxz33GpLaYfNoeq3HWB+J7tAcmMc5KWePn4UT0H4W U5coQj4XQ+nEJ9w4ve0vDb/fnekb/FCt37urEB7HJT32pAYiW60Cokqb+MH+A3jTMZbwBIVkDpwkm B7ouLmE/50YgkXpVjrlL4GpZvgPMs5ILK4BvK8tMQpEHPs1RE5IYFPEfbvOEzBMZ9VLmqIsGMA7v9 SVfuHKJdg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWgG-0003PO-92; Fri, 30 Oct 2020 15:51:08 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWeq-0002wi-EJ for linux-arm-kernel@lists.infradead.org; Fri, 30 Oct 2020 15:49:51 +0000 Received: from localhost.localdomain (HSI-KBW-46-223-126-90.hsi.kabel-badenwuerttemberg.de [46.223.126.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 678A0206E9; Fri, 30 Oct 2020 15:49:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604072979; bh=v4W+rSkvG9WdcPfSNfBGl6XjWSXTtC1rvveEB/jtQ0w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XqTBWM/aCsrmb4Tgi139hX/RSflNORGj9TBXdOTLU3VWg3oXN09auBrmiyxfD7l7s jP5NJCppEO2q8rAxXZgSlJP5r9YqZvxzDq+BRPp+fec+f8i1i7FravE+RhO6dmLMG2 4mf65FFZgvd5YsjohMNAZd1o4yHtKx2Zv0l9npvo= From: Arnd Bergmann To: Russell King , Christoph Hellwig Subject: [PATCH 5/9] ARM: oabi-compat: rework epoll_wait/epoll_pwait emulation Date: Fri, 30 Oct 2020 16:49:15 +0100 Message-Id: <20201030154919.1246645-5-arnd@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201030154919.1246645-1-arnd@kernel.org> References: <20201030154519.1245983-1-arnd@kernel.org> <20201030154919.1246645-1-arnd@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201030_114940_789766_C87DD093 X-CRM114-Status: GOOD ( 28.45 ) 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: linux-arch@vger.kernel.org, arnd@arndb.de, linus.walleij@linaro.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Arnd Bergmann The epoll_wait() system call wrapper is one of the remaining users of the set_fs() infrasturcture for Arm. Changing it to not require set_fs() is rather complex unfortunately. The approach I'm taking here is to allow architectures to override the code that copies the output to user space, and let the oabi-compat implementation check whether it is getting called from an EABI or OABI system call based on the thread_info->syscall value. The in_oabi_syscall() check here mirrors the in_compat_syscall() and in_x32_syscall() helpers for 32-bit compat implementations on other architectures. Overall, the amount of code goes down, at least with the newly added sys_oabi_epoll_pwait() helper getting removed again. The downside is added complexity in the source code for the native implementation. There should be no difference in runtime performance except for Arm kernels with CONFIG_OABI_COMPAT enabled that now have to go through an external function call to check which of the two variants to use. Signed-off-by: Arnd Bergmann --- arch/arm/include/asm/syscall.h | 11 +++++ arch/arm/kernel/sys_oabi-compat.c | 75 +++++++------------------------ arch/arm/tools/syscall.tbl | 4 +- fs/eventpoll.c | 5 +-- include/linux/eventpoll.h | 18 ++++++++ 5 files changed, 49 insertions(+), 64 deletions(-) diff --git a/arch/arm/include/asm/syscall.h b/arch/arm/include/asm/syscall.h index 89898497edd6..9efb7b3384e5 100644 --- a/arch/arm/include/asm/syscall.h +++ b/arch/arm/include/asm/syscall.h @@ -28,6 +28,17 @@ static inline int syscall_get_nr(struct task_struct *task, return task_thread_info(task)->syscall & ~__NR_OABI_SYSCALL_BASE; } +static inline bool __in_oabi_syscall(struct task_struct *task) +{ + return IS_ENABLED(CONFIG_OABI_COMPAT) && + (task_thread_info(task)->syscall & __NR_OABI_SYSCALL_BASE); +} + +static inline bool in_oabi_syscall(void) +{ + return __in_oabi_syscall(current); +} + static inline void syscall_rollback(struct task_struct *task, struct pt_regs *regs) { diff --git a/arch/arm/kernel/sys_oabi-compat.c b/arch/arm/kernel/sys_oabi-compat.c index a2b1ae01e5bf..f9d8e5be6ba0 100644 --- a/arch/arm/kernel/sys_oabi-compat.c +++ b/arch/arm/kernel/sys_oabi-compat.c @@ -83,6 +83,8 @@ #include #include +#include + struct oldabi_stat64 { unsigned long long st_dev; unsigned int __pad1; @@ -264,70 +266,25 @@ asmlinkage long sys_oabi_epoll_ctl(int epfd, int op, int fd, return do_epoll_ctl(epfd, op, fd, &kernel, false); } -static long do_oabi_epoll_wait(int epfd, struct oabi_epoll_event __user *events, - int maxevents, int timeout) +struct epoll_event __user * +epoll_put_uevent(__poll_t revents, __u64 data, + struct epoll_event __user *uevent) { - struct epoll_event *kbuf; - struct oabi_epoll_event e; - mm_segment_t fs; - long ret, err, i; + if (in_oabi_syscall()) { + struct oabi_epoll_event __user *oevent = (void __user *)uevent; - if (maxevents <= 0 || - maxevents > (INT_MAX/sizeof(*kbuf)) || - maxevents > (INT_MAX/sizeof(*events))) - return -EINVAL; - if (!access_ok(events, sizeof(*events) * maxevents)) - return -EFAULT; - kbuf = kmalloc_array(maxevents, sizeof(*kbuf), GFP_KERNEL); - if (!kbuf) - return -ENOMEM; - fs = get_fs(); - set_fs(KERNEL_DS); - ret = sys_epoll_wait(epfd, kbuf, maxevents, timeout); - set_fs(fs); - err = 0; - for (i = 0; i < ret; i++) { - e.events = kbuf[i].events; - e.data = kbuf[i].data; - err = __copy_to_user(events, &e, sizeof(e)); - if (err) - break; - events++; - } - kfree(kbuf); - return err ? -EFAULT : ret; -} + if (__put_user(revents, &oevent->events) || + __put_user(data, &oevent->data)) + return NULL; -SYSCALL_DEFINE4(oabi_epoll_wait, int, epfd, - struct oabi_epoll_event __user *, events, - int, maxevents, int, timeout) -{ - return do_oabi_epoll_wait(epfd, events, maxevents, timeout); -} - -/* - * Implement the event wait interface for the eventpoll file. It is the kernel - * part of the user space epoll_pwait(2). - */ -SYSCALL_DEFINE6(oabi_epoll_pwait, int, epfd, - struct oabi_epoll_event __user *, events, int, maxevents, - int, timeout, const sigset_t __user *, sigmask, - size_t, sigsetsize) -{ - int error; - - /* - * If the caller wants a certain signal mask to be set during the wait, - * we apply it here. - */ - error = set_user_sigmask(sigmask, sigsetsize); - if (error) - return error; + return (void __user *)(oevent+1); + } - error = do_oabi_epoll_wait(epfd, events, maxevents, timeout); - restore_saved_sigmask_unless(error == -EINTR); + if (__put_user(revents, &uevent->events) || + __put_user(data, &uevent->data)) + return NULL; - return error; + return uevent+1; } struct oabi_sembuf { diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index 330cf0aa04c4..2dd99f86e8a5 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -266,7 +266,7 @@ 249 common lookup_dcookie sys_lookup_dcookie 250 common epoll_create sys_epoll_create 251 common epoll_ctl sys_epoll_ctl sys_oabi_epoll_ctl -252 common epoll_wait sys_epoll_wait sys_oabi_epoll_wait +252 common epoll_wait sys_epoll_wait 253 common remap_file_pages sys_remap_file_pages # 254 for set_thread_area # 255 for get_thread_area @@ -360,7 +360,7 @@ 343 common vmsplice sys_vmsplice 344 common move_pages sys_move_pages 345 common getcpu sys_getcpu -346 common epoll_pwait sys_epoll_pwait sys_oabi_epoll_pwait +346 common epoll_pwait sys_epoll_pwait 347 common kexec_load sys_kexec_load 348 common utimensat sys_utimensat_time32 349 common signalfd sys_signalfd diff --git a/fs/eventpoll.c b/fs/eventpoll.c index 4df61129566d..a21e8dbbe567 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -1743,8 +1743,8 @@ static __poll_t ep_send_events_proc(struct eventpoll *ep, struct list_head *head if (!revents) continue; - if (__put_user(revents, &uevent->events) || - __put_user(epi->event.data, &uevent->data)) { + uevent = epoll_put_uevent(revents, epi->event.data, uevent); + if (!uevent) { list_add(&epi->rdllink, head); ep_pm_stay_awake(epi); if (!esed->res) @@ -1752,7 +1752,6 @@ static __poll_t ep_send_events_proc(struct eventpoll *ep, struct list_head *head return 0; } esed->res++; - uevent++; if (epi->event.events & EPOLLONESHOT) epi->event.events &= EP_PRIVATE_BITS; else if (!(epi->event.events & EPOLLET)) { diff --git a/include/linux/eventpoll.h b/include/linux/eventpoll.h index 8f000fada5a4..d1f13147ed69 100644 --- a/include/linux/eventpoll.h +++ b/include/linux/eventpoll.h @@ -77,4 +77,22 @@ static inline void eventpoll_release(struct file *file) {} #endif +#if defined(CONFIG_ARM) && defined(CONFIG_OABI_COMPAT) +/* ARM OABI has an incompatible struct layout and needs a special handler */ +extern struct epoll_event __user * +epoll_put_uevent(__poll_t revents, __u64 data, + struct epoll_event __user *uevent); +#else +static inline struct epoll_event __user * +epoll_put_uevent(__poll_t revents, __u64 data, + struct epoll_event __user *uevent) +{ + if (__put_user(revents, &uevent->events) || + __put_user(data, &uevent->data)) + return NULL; + + return uevent+1; +} +#endif + #endif /* #ifndef _LINUX_EVENTPOLL_H */ From patchwork Fri Oct 30 15:49:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 11870355 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 BD136C4741F for ; Fri, 30 Oct 2020 17:04:16 +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 31CAB2075E for ; Fri, 30 Oct 2020 17:04:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="pB3yGj44"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="tNj45Aqw" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 31CAB2075E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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=FfBc6UNuh1W/C6rS3A9x+/p/jeaek0/VaO+QwOqOrxQ=; b=pB3yGj44w+DLdX2OY4/c5gGIp Jp/AjvYPOi1q8SPxH6oOWddwF0taXqeORIG952C5ny5Hrjxd7Odt+o9jb0poFtg9sCc1ardfKBRO8 PR0eZm3ue2ZY36Xow3aqkfb1CaML6fmjsfYulpBsgHbzOtq1d8CwqFJ8VUOeVknLeNQTDHiodl8En hyD/BHKWzlLxIn8D5RwzfcT1qF+FVAXKriscVIMk2EhSwWh3QqRQFwMDE1YLDZuUNo7CxtWn0I/mY UqFgVJCcZBGnTp+7qEQqSR6+a72PDYsLkEla1CRXnZ39GQUidFIjGrv5D6SdzMQyuM2HiwdRFxgHB IERpIezbQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYXnx-0001Bg-0J; Fri, 30 Oct 2020 17:03:09 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWes-0002xr-H7 for linux-arm-kernel@lists.infradead.org; Fri, 30 Oct 2020 15:49:51 +0000 Received: from localhost.localdomain (HSI-KBW-46-223-126-90.hsi.kabel-badenwuerttemberg.de [46.223.126.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B0A3320A8B; Fri, 30 Oct 2020 15:49:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604072981; bh=Nohcs14NXVmzDPgy7u84GYyJC54hRaPFadvgsNBjXrI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tNj45AqwPZGaVSNZpP/1A40HzTQLDVBwf2c34+4NvqbGTUhoh/FO1BRqJrOzNVruE LD4BOIie9hoNn4iQjlQcwnREWhJReYlSVouLAnKm8M47AUNXUKe7p+0J5aXJlKS3Jx fB308cFDSQauT/MWaRTsr+6FJpvDCoAqru2H5sJE= From: Arnd Bergmann To: Russell King , Christoph Hellwig Subject: [PATCH 6/9] ARM: oabi-compat: rework sys_semtimedop emulation Date: Fri, 30 Oct 2020 16:49:16 +0100 Message-Id: <20201030154919.1246645-6-arnd@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201030154919.1246645-1-arnd@kernel.org> References: <20201030154519.1245983-1-arnd@kernel.org> <20201030154919.1246645-1-arnd@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201030_114942_900899_F0AF6662 X-CRM114-Status: GOOD ( 30.00 ) 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: linux-arch@vger.kernel.org, arnd@arndb.de, linus.walleij@linaro.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Arnd Bergmann sys_oabi_semtimedop() is one of the last users of set_fs() on Arm. To remove this one, expose the internal code of the actual implementation that operates on a kernel pointer and call it directly after copying. There should be no measurable impact on the normal execution of this function, and it makes the overly long function a little shorter, which may help readability. While reworking the oabi version, make it behave a little more like the native one, using kvmalloc_array() and restructure the code flow in a similar way. The naming of __do_semtimedop() is not very good, I hope someone can come up with a better name. One regression was spotted by kernel test robot and fixed before the first mailing list submission. Signed-off-by: Arnd Bergmann --- arch/arm/kernel/sys_oabi-compat.c | 38 ++++++++------ include/linux/syscalls.h | 3 ++ ipc/sem.c | 84 +++++++++++++++++++------------ 3 files changed, 77 insertions(+), 48 deletions(-) diff --git a/arch/arm/kernel/sys_oabi-compat.c b/arch/arm/kernel/sys_oabi-compat.c index f9d8e5be6ba0..c3e63b73b6ae 100644 --- a/arch/arm/kernel/sys_oabi-compat.c +++ b/arch/arm/kernel/sys_oabi-compat.c @@ -80,6 +80,7 @@ #include #include #include +#include #include #include @@ -294,46 +295,51 @@ struct oabi_sembuf { unsigned short __pad; }; +#define sc_semopm sem_ctls[2] + asmlinkage long sys_oabi_semtimedop(int semid, struct oabi_sembuf __user *tsops, unsigned nsops, const struct old_timespec32 __user *timeout) { + struct ipc_namespace *ns; struct sembuf *sops; - struct old_timespec32 local_timeout; long err; int i; + ns = current->nsproxy->ipc_ns; + if (nsops > ns->sc_semopm) + return -E2BIG; if (nsops < 1 || nsops > SEMOPM) return -EINVAL; - if (!access_ok(tsops, sizeof(*tsops) * nsops)) - return -EFAULT; - sops = kmalloc_array(nsops, sizeof(*sops), GFP_KERNEL); + sops = kvmalloc_array(nsops, sizeof(*sops), GFP_KERNEL); if (!sops) return -ENOMEM; err = 0; for (i = 0; i < nsops; i++) { struct oabi_sembuf osb; - err |= __copy_from_user(&osb, tsops, sizeof(osb)); + err |= copy_from_user(&osb, tsops, sizeof(osb)); sops[i].sem_num = osb.sem_num; sops[i].sem_op = osb.sem_op; sops[i].sem_flg = osb.sem_flg; tsops++; } - if (timeout) { - /* copy this as well before changing domain protection */ - err |= copy_from_user(&local_timeout, timeout, sizeof(*timeout)); - timeout = &local_timeout; - } if (err) { err = -EFAULT; - } else { - mm_segment_t fs = get_fs(); - set_fs(KERNEL_DS); - err = sys_semtimedop_time32(semid, sops, nsops, timeout); - set_fs(fs); + goto out; + } + + if (timeout) { + struct timespec64 ts; + err = get_old_timespec32(&ts, timeout); + if (err) + goto out; + err = __do_semtimedop(semid, sops, nsops, &ts, ns); + goto out; } - kfree(sops); + err = __do_semtimedop(semid, sops, nsops, NULL, ns); +out: + kvfree(sops); return err; } diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 37bea07c12f2..fc7340fa4702 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -1342,6 +1342,9 @@ long ksys_old_shmctl(int shmid, int cmd, struct shmid_ds __user *buf); long compat_ksys_semtimedop(int semid, struct sembuf __user *tsems, unsigned int nsops, const struct old_timespec32 __user *timeout); +long __do_semtimedop(int semid, struct sembuf *tsems, unsigned int nsops, + const struct timespec64 *timeout, + struct ipc_namespace *ns); int __sys_getsockopt(int fd, int level, int optname, char __user *optval, int __user *optlen); diff --git a/ipc/sem.c b/ipc/sem.c index f6c30a85dadf..c7725031c2ba 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -1978,46 +1978,34 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) return un; } -static long do_semtimedop(int semid, struct sembuf __user *tsops, - unsigned nsops, const struct timespec64 *timeout) +long __do_semtimedop(int semid, struct sembuf *sops, + unsigned nsops, const struct timespec64 *timeout, + struct ipc_namespace *ns) { int error = -EINVAL; struct sem_array *sma; - struct sembuf fast_sops[SEMOPM_FAST]; - struct sembuf *sops = fast_sops, *sop; + struct sembuf *sop; struct sem_undo *un; int max, locknum; bool undos = false, alter = false, dupsop = false; struct sem_queue queue; unsigned long dup = 0, jiffies_left = 0; - struct ipc_namespace *ns; - - ns = current->nsproxy->ipc_ns; if (nsops < 1 || semid < 0) return -EINVAL; if (nsops > ns->sc_semopm) return -E2BIG; - if (nsops > SEMOPM_FAST) { - sops = kvmalloc_array(nsops, sizeof(*sops), GFP_KERNEL); - if (sops == NULL) - return -ENOMEM; - } - - if (copy_from_user(sops, tsops, nsops * sizeof(*tsops))) { - error = -EFAULT; - goto out_free; - } if (timeout) { if (timeout->tv_sec < 0 || timeout->tv_nsec < 0 || timeout->tv_nsec >= 1000000000L) { error = -EINVAL; - goto out_free; + goto out; } jiffies_left = timespec64_to_jiffies(timeout); } + max = 0; for (sop = sops; sop < sops + nsops; sop++) { unsigned long mask = 1ULL << ((sop->sem_num) % BITS_PER_LONG); @@ -2046,7 +2034,7 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops, un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); - goto out_free; + goto out; } } else { un = NULL; @@ -2057,25 +2045,25 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops, if (IS_ERR(sma)) { rcu_read_unlock(); error = PTR_ERR(sma); - goto out_free; + goto out; } error = -EFBIG; if (max >= sma->sem_nsems) { rcu_read_unlock(); - goto out_free; + goto out; } error = -EACCES; if (ipcperms(ns, &sma->sem_perm, alter ? S_IWUGO : S_IRUGO)) { rcu_read_unlock(); - goto out_free; + goto out; } error = security_sem_semop(&sma->sem_perm, sops, nsops, alter); if (error) { rcu_read_unlock(); - goto out_free; + goto out; } error = -EIDRM; @@ -2089,7 +2077,7 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops, * entangled here and why it's RMID race safe on comments at sem_lock() */ if (!ipc_valid_object(&sma->sem_perm)) - goto out_unlock_free; + goto out_unlock; /* * semid identifiers are not unique - find_alloc_undo may have * allocated an undo structure, it was invalidated by an RMID @@ -2098,7 +2086,7 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops, * "un" itself is guaranteed by rcu. */ if (un && un->semid == -1) - goto out_unlock_free; + goto out_unlock; queue.sops = sops; queue.nsops = nsops; @@ -2124,10 +2112,10 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops, rcu_read_unlock(); wake_up_q(&wake_q); - goto out_free; + goto out; } if (error < 0) /* non-blocking error path */ - goto out_unlock_free; + goto out_unlock; /* * We need to sleep on this operation, so we put the current @@ -2192,14 +2180,14 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops, if (error != -EINTR) { /* see SEM_BARRIER_2 for purpose/pairing */ smp_acquire__after_ctrl_dep(); - goto out_free; + goto out; } rcu_read_lock(); locknum = sem_lock(sma, sops, nsops); if (!ipc_valid_object(&sma->sem_perm)) - goto out_unlock_free; + goto out_unlock; /* * No necessity for any barrier: We are protect by sem_lock() @@ -2211,7 +2199,7 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops, * Leave without unlink_queue(), but with sem_unlock(). */ if (error != -EINTR) - goto out_unlock_free; + goto out_unlock; /* * If an interrupt occurred we have to clean up the queue. @@ -2222,13 +2210,45 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops, unlink_queue(sma, &queue); -out_unlock_free: +out_unlock: sem_unlock(sma, locknum); rcu_read_unlock(); +out: + return error; +} + +static long do_semtimedop(int semid, struct sembuf __user *tsops, + unsigned nsops, const struct timespec64 *timeout) +{ + struct sembuf fast_sops[SEMOPM_FAST]; + struct sembuf *sops = fast_sops; + struct ipc_namespace *ns; + int ret; + + ns = current->nsproxy->ipc_ns; + if (nsops > ns->sc_semopm) + return -E2BIG; + if (nsops < 1) + return -EINVAL; + + if (nsops > SEMOPM_FAST) { + sops = kvmalloc_array(nsops, sizeof(*sops), GFP_KERNEL); + if (sops == NULL) + return -ENOMEM; + } + + if (copy_from_user(sops, tsops, nsops * sizeof(*tsops))) { + ret = -EFAULT; + goto out_free; + } + + ret = __do_semtimedop(semid, sops, nsops, timeout, ns); + out_free: if (sops != fast_sops) kvfree(sops); - return error; + + return ret; } long ksys_semtimedop(int semid, struct sembuf __user *tsops, From patchwork Fri Oct 30 15:49:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 11870173 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 D503EC00A89 for ; Fri, 30 Oct 2020 15:53:11 +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 5A6012067D for ; Fri, 30 Oct 2020 15:53:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="2jgRBbSp"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="ugPQTkip" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5A6012067D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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=jLjgLH/QwNLAX5Ydtkuzevp2szKS/FobqkZsCHPzbX0=; b=2jgRBbSppyk4uJrnurprNZumt gvGW2ta/18Kwsdl2i/6sv7oxuL+Z7SdrOaICEEKe8D+HoYzsGaVrV+w296Gv21pnVuYqvJBe94WXz rIGJllsIqGTOjQBvGT14sNXR+lKVwTC+Dt48WxmuGV6JRhHQoJGnA9hKrFoVmYF7H5nuChSZIw0rU 8Kn+ADZ4yC+CmiTjGpEYExdV56rkMKb7nye5he7nn2yBl7nkaXdxPU+Ibhvfxc5YSm0kY2JTCmlXM 9Z/N4mV7hqiYJgqVVyvCVUx3c/fLuxRHfKkGPVE+N4yo6626AfuXMSAzj2lrFuA197S4migmDeDxP bGQMgIiKw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWgi-0003Ys-48; Fri, 30 Oct 2020 15:51:36 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWev-0002yg-9Y for linux-arm-kernel@lists.infradead.org; Fri, 30 Oct 2020 15:49:56 +0000 Received: from localhost.localdomain (HSI-KBW-46-223-126-90.hsi.kabel-badenwuerttemberg.de [46.223.126.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0B43B22241; Fri, 30 Oct 2020 15:49:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604072983; bh=Mx21NEzsW0sqOlRSKKtH114cIyZ8zXg4jMUbhna5VF0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ugPQTkip7iCrZSHrqBz6Pc8ED6zMvRtbryCcPbLZLzqUBWWz6eL+SfaLIu5/pSc6V TS+HeRVtV2vG7RW/aipBaP6YOToLXIC/1wQbnJfLxsTA22Cfp/tGzuBNIK8DWVVd2Q CGoec7enG38Hfk3qgtSkzJ35WeM5bIJXZf0w67YQ= From: Arnd Bergmann To: Russell King , Christoph Hellwig Subject: [PATCH 7/9] ARM: oabi-compat: rework fcntl64() emulation Date: Fri, 30 Oct 2020 16:49:17 +0100 Message-Id: <20201030154919.1246645-7-arnd@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201030154919.1246645-1-arnd@kernel.org> References: <20201030154519.1245983-1-arnd@kernel.org> <20201030154919.1246645-1-arnd@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201030_114945_611709_FF576BA5 X-CRM114-Status: GOOD ( 18.62 ) 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: linux-arch@vger.kernel.org, arnd@arndb.de, linus.walleij@linaro.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Arnd Bergmann This is one of the last users of get_fs(), and this is fairly easy to change, since the infrastructure for it is already there. The replacement here is essentially a copy of the existing fcntl64() syscall entry function. Signed-off-by: Arnd Bergmann --- arch/arm/kernel/sys_oabi-compat.c | 93 ++++++++++++++++++++----------- 1 file changed, 60 insertions(+), 33 deletions(-) diff --git a/arch/arm/kernel/sys_oabi-compat.c b/arch/arm/kernel/sys_oabi-compat.c index c3e63b73b6ae..3449e163ea88 100644 --- a/arch/arm/kernel/sys_oabi-compat.c +++ b/arch/arm/kernel/sys_oabi-compat.c @@ -194,56 +194,83 @@ struct oabi_flock64 { pid_t l_pid; } __attribute__ ((packed,aligned(4))); -static long do_locks(unsigned int fd, unsigned int cmd, - unsigned long arg) +static int get_oabi_flock(struct flock64 *kernel, struct oabi_flock64 __user *arg) { - struct flock64 kernel; struct oabi_flock64 user; - mm_segment_t fs; - long ret; if (copy_from_user(&user, (struct oabi_flock64 __user *)arg, sizeof(user))) return -EFAULT; - kernel.l_type = user.l_type; - kernel.l_whence = user.l_whence; - kernel.l_start = user.l_start; - kernel.l_len = user.l_len; - kernel.l_pid = user.l_pid; - - fs = get_fs(); - set_fs(KERNEL_DS); - ret = sys_fcntl64(fd, cmd, (unsigned long)&kernel); - set_fs(fs); - - if (!ret && (cmd == F_GETLK64 || cmd == F_OFD_GETLK)) { - user.l_type = kernel.l_type; - user.l_whence = kernel.l_whence; - user.l_start = kernel.l_start; - user.l_len = kernel.l_len; - user.l_pid = kernel.l_pid; - if (copy_to_user((struct oabi_flock64 __user *)arg, - &user, sizeof(user))) - ret = -EFAULT; - } - return ret; + + kernel->l_type = user.l_type; + kernel->l_whence = user.l_whence; + kernel->l_start = user.l_start; + kernel->l_len = user.l_len; + kernel->l_pid = user.l_pid; + + return 0; +} + +static int put_oabi_flock(struct flock64 *kernel, struct oabi_flock64 __user *arg) +{ + struct oabi_flock64 user; + + user.l_type = kernel->l_type; + user.l_whence = kernel->l_whence; + user.l_start = kernel->l_start; + user.l_len = kernel->l_len; + user.l_pid = kernel->l_pid; + + if (copy_to_user((struct oabi_flock64 __user *)arg, + &user, sizeof(user))) + return -EFAULT; + + return 0; } asmlinkage long sys_oabi_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg) { + void __user *argp = (void __user *)arg; + struct fd f = fdget_raw(fd); + struct flock64 flock; + long err = -EBADF; + + if (!f.file) + goto out; + switch (cmd) { - case F_OFD_GETLK: - case F_OFD_SETLK: - case F_OFD_SETLKW: case F_GETLK64: + case F_OFD_GETLK: + err = security_file_fcntl(f.file, cmd, arg); + if (err) + break; + err = get_oabi_flock(&flock, argp); + if (err) + break; + err = fcntl_getlk64(f.file, cmd, &flock); + if (!err) + err = put_oabi_flock(&flock, argp); + break; case F_SETLK64: case F_SETLKW64: - return do_locks(fd, cmd, arg); - + case F_OFD_SETLK: + case F_OFD_SETLKW: + err = security_file_fcntl(f.file, cmd, arg); + if (err) + break; + err = get_oabi_flock(&flock, argp); + if (err) + break; + err = fcntl_setlk64(fd, f.file, cmd, &flock); + break; default: - return sys_fcntl64(fd, cmd, arg); + err = sys_fcntl64(fd, cmd, arg); + break; } + fdput(f); +out: + return err; } struct oabi_epoll_event { From patchwork Fri Oct 30 15:49:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 11870171 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 99BE9C00A89 for ; Fri, 30 Oct 2020 15:52:39 +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 1D6AD206CA for ; Fri, 30 Oct 2020 15:52:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="L/oeFQId"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="R0a5HNrB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1D6AD206CA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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=uT6lFgIpDWZZFb6MNP5odkw2tm4y+u+Nzs1/SqMWWFM=; b=L/oeFQIdqmGuVnggUwcfAa6nr VV50ssZzMrntfmm+dvJsat2Rhe64oZhQXTDUdn5uQ/t7EkL88paqd5L7QswPW/24m/IWzRk/KB2mh Y+pURMVxQ5gG/lzSxaynktTaMX3ITqutMUYHszUJvmQBaElEmE8mGIdEdhD52su2GLoYOLrtRmqzI 4ftWmFrt6HKczdQE2v0u7wos9u2h7qXTD9gI/sYAZTGJzfndElMDBoJ0ywtbXha0/6KXECZ4XBa82 zBhvQUhqfSg8ea0jbQs6uYsqZz6R+pmckZs9USeLJj3oui05ccfMByM0azDIKzu7O/kDL1H+Iv2ng IGo36CD9w==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWh3-0003fM-4T; Fri, 30 Oct 2020 15:51:57 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWex-00030C-33 for linux-arm-kernel@lists.infradead.org; Fri, 30 Oct 2020 15:50:02 +0000 Received: from localhost.localdomain (HSI-KBW-46-223-126-90.hsi.kabel-badenwuerttemberg.de [46.223.126.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5308F22253; Fri, 30 Oct 2020 15:49:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604072986; bh=dw+FNOj9rldGYjGgvqnlK7d2jveyytjZONsX8DAT/q4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=R0a5HNrBIRQUBu6ig7nuv+MepNXNQ24+T16k0PcALBnQZR4OF92jeVXmuZSrRVNd6 XZ5W5D//tVylebaXnmmw2zHAt37AnRO8154mQwRo1xA0cfvtRiA++v20bomKsCI+V5 yyEMPB23AsmMXSFWEGc+XVUndufFs2TfKX+nvOUg= From: Arnd Bergmann To: Russell King , Christoph Hellwig Subject: [PATCH 8/9] ARM: uaccess: add __{get,put}_kernel_nofault Date: Fri, 30 Oct 2020 16:49:18 +0100 Message-Id: <20201030154919.1246645-8-arnd@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201030154919.1246645-1-arnd@kernel.org> References: <20201030154519.1245983-1-arnd@kernel.org> <20201030154919.1246645-1-arnd@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201030_114947_387468_D9E2FDF4 X-CRM114-Status: GOOD ( 19.00 ) 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: linux-arch@vger.kernel.org, arnd@arndb.de, linus.walleij@linaro.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Arnd Bergmann These mimic the behavior of get_user and put_user, except for domain switching, address limit checking and handling of mismatched sizes, none of which are relevant here. To work with pre-Armv6 kernels, this has to avoid TUSER() inside of the new macros, the new approach passes the "t" string along with the opcode, which is a bit uglier but avoids duplicating more code. As there is no __get_user_asm_dword(), I work around it by copying 32 bit at a time, which is possible because the output size is known. Signed-off-by: Arnd Bergmann --- arch/arm/include/asm/uaccess.h | 123 ++++++++++++++++++++++----------- 1 file changed, 83 insertions(+), 40 deletions(-) diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index a13d90206472..4f60638755c4 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -308,11 +308,11 @@ static inline void set_fs(mm_segment_t fs) #define __get_user(x, ptr) \ ({ \ long __gu_err = 0; \ - __get_user_err((x), (ptr), __gu_err); \ + __get_user_err((x), (ptr), __gu_err, TUSER()); \ __gu_err; \ }) -#define __get_user_err(x, ptr, err) \ +#define __get_user_err(x, ptr, err, __t) \ do { \ unsigned long __gu_addr = (unsigned long)(ptr); \ unsigned long __gu_val; \ @@ -321,18 +321,19 @@ do { \ might_fault(); \ __ua_flags = uaccess_save_and_enable(); \ switch (sizeof(*(ptr))) { \ - case 1: __get_user_asm_byte(__gu_val, __gu_addr, err); break; \ - case 2: __get_user_asm_half(__gu_val, __gu_addr, err); break; \ - case 4: __get_user_asm_word(__gu_val, __gu_addr, err); break; \ + case 1: __get_user_asm_byte(__gu_val, __gu_addr, err, __t); break; \ + case 2: __get_user_asm_half(__gu_val, __gu_addr, err, __t); break; \ + case 4: __get_user_asm_word(__gu_val, __gu_addr, err, __t); break; \ default: (__gu_val) = __get_user_bad(); \ } \ uaccess_restore(__ua_flags); \ (x) = (__typeof__(*(ptr)))__gu_val; \ } while (0) +#endif #define __get_user_asm(x, addr, err, instr) \ __asm__ __volatile__( \ - "1: " TUSER(instr) " %1, [%2], #0\n" \ + "1: " instr " %1, [%2], #0\n" \ "2:\n" \ " .pushsection .text.fixup,\"ax\"\n" \ " .align 2\n" \ @@ -348,40 +349,38 @@ do { \ : "r" (addr), "i" (-EFAULT) \ : "cc") -#define __get_user_asm_byte(x, addr, err) \ - __get_user_asm(x, addr, err, ldrb) +#define __get_user_asm_byte(x, addr, err, __t) \ + __get_user_asm(x, addr, err, "ldrb" __t) #if __LINUX_ARM_ARCH__ >= 6 -#define __get_user_asm_half(x, addr, err) \ - __get_user_asm(x, addr, err, ldrh) +#define __get_user_asm_half(x, addr, err, __t) \ + __get_user_asm(x, addr, err, "ldrh" __t) #else #ifndef __ARMEB__ -#define __get_user_asm_half(x, __gu_addr, err) \ +#define __get_user_asm_half(x, __gu_addr, err, __t) \ ({ \ unsigned long __b1, __b2; \ - __get_user_asm_byte(__b1, __gu_addr, err); \ - __get_user_asm_byte(__b2, __gu_addr + 1, err); \ + __get_user_asm_byte(__b1, __gu_addr, err, __t); \ + __get_user_asm_byte(__b2, __gu_addr + 1, err, __t); \ (x) = __b1 | (__b2 << 8); \ }) #else -#define __get_user_asm_half(x, __gu_addr, err) \ +#define __get_user_asm_half(x, __gu_addr, err, __t) \ ({ \ unsigned long __b1, __b2; \ - __get_user_asm_byte(__b1, __gu_addr, err); \ - __get_user_asm_byte(__b2, __gu_addr + 1, err); \ + __get_user_asm_byte(__b1, __gu_addr, err, __t); \ + __get_user_asm_byte(__b2, __gu_addr + 1, err, __t); \ (x) = (__b1 << 8) | __b2; \ }) #endif #endif /* __LINUX_ARM_ARCH__ >= 6 */ -#define __get_user_asm_word(x, addr, err) \ - __get_user_asm(x, addr, err, ldr) -#endif - +#define __get_user_asm_word(x, addr, err, __t) \ + __get_user_asm(x, addr, err, "ldr" __t) #define __put_user_switch(x, ptr, __err, __fn) \ do { \ @@ -425,7 +424,7 @@ do { \ #define __put_user_nocheck(x, __pu_ptr, __err, __size) \ do { \ unsigned long __pu_addr = (unsigned long)__pu_ptr; \ - __put_user_nocheck_##__size(x, __pu_addr, __err); \ + __put_user_nocheck_##__size(x, __pu_addr, __err, TUSER());\ } while (0) #define __put_user_nocheck_1 __put_user_asm_byte @@ -433,9 +432,11 @@ do { \ #define __put_user_nocheck_4 __put_user_asm_word #define __put_user_nocheck_8 __put_user_asm_dword +#endif /* !CONFIG_CPU_SPECTRE */ + #define __put_user_asm(x, __pu_addr, err, instr) \ __asm__ __volatile__( \ - "1: " TUSER(instr) " %1, [%2], #0\n" \ + "1: " instr " %1, [%2], #0\n" \ "2:\n" \ " .pushsection .text.fixup,\"ax\"\n" \ " .align 2\n" \ @@ -450,36 +451,36 @@ do { \ : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \ : "cc") -#define __put_user_asm_byte(x, __pu_addr, err) \ - __put_user_asm(x, __pu_addr, err, strb) +#define __put_user_asm_byte(x, __pu_addr, err, __t) \ + __put_user_asm(x, __pu_addr, err, "strb" __t) #if __LINUX_ARM_ARCH__ >= 6 -#define __put_user_asm_half(x, __pu_addr, err) \ - __put_user_asm(x, __pu_addr, err, strh) +#define __put_user_asm_half(x, __pu_addr, err, __t) \ + __put_user_asm(x, __pu_addr, err, "strh" __t) #else #ifndef __ARMEB__ -#define __put_user_asm_half(x, __pu_addr, err) \ +#define __put_user_asm_half(x, __pu_addr, err, __t) \ ({ \ unsigned long __temp = (__force unsigned long)(x); \ - __put_user_asm_byte(__temp, __pu_addr, err); \ - __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \ + __put_user_asm_byte(__temp, __pu_addr, err, __t); \ + __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err, __t);\ }) #else -#define __put_user_asm_half(x, __pu_addr, err) \ +#define __put_user_asm_half(x, __pu_addr, err, __t) \ ({ \ unsigned long __temp = (__force unsigned long)(x); \ - __put_user_asm_byte(__temp >> 8, __pu_addr, err); \ - __put_user_asm_byte(__temp, __pu_addr + 1, err); \ + __put_user_asm_byte(__temp >> 8, __pu_addr, err, __t); \ + __put_user_asm_byte(__temp, __pu_addr + 1, err, __t); \ }) #endif #endif /* __LINUX_ARM_ARCH__ >= 6 */ -#define __put_user_asm_word(x, __pu_addr, err) \ - __put_user_asm(x, __pu_addr, err, str) +#define __put_user_asm_word(x, __pu_addr, err, __t) \ + __put_user_asm(x, __pu_addr, err, "str" __t) #ifndef __ARMEB__ #define __reg_oper0 "%R2" @@ -489,12 +490,12 @@ do { \ #define __reg_oper1 "%R2" #endif -#define __put_user_asm_dword(x, __pu_addr, err) \ +#define __put_user_asm_dword(x, __pu_addr, err, __t) \ __asm__ __volatile__( \ - ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \ - ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \ - THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \ - THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \ + ARM( "1: str" __t " " __reg_oper1 ", [%1], #4\n" ) \ + ARM( "2: str" __t " " __reg_oper0 ", [%1]\n" ) \ + THUMB( "1: str" __t " " __reg_oper1 ", [%1]\n" ) \ + THUMB( "2: str" __t " " __reg_oper0 ", [%1, #4]\n" ) \ "3:\n" \ " .pushsection .text.fixup,\"ax\"\n" \ " .align 2\n" \ @@ -510,7 +511,49 @@ do { \ : "r" (x), "i" (-EFAULT) \ : "cc") -#endif /* !CONFIG_CPU_SPECTRE */ +#define HAVE_GET_KERNEL_NOFAULT + +#define __get_kernel_nofault(dst, src, type, err_label) \ +do { \ + const type *__pk_ptr = (src); \ + unsigned long __src = (unsigned long)(__pk_ptr); \ + type __val; \ + int __err = 0; \ + switch (sizeof(type)) { \ + case 1: __get_user_asm_byte(__val, __src, __err, ""); break; \ + case 2: __get_user_asm_half(__val, __src, __err, ""); break; \ + case 4: __get_user_asm_word(__val, __src, __err, ""); break; \ + case 8: { \ + u32 *__v32 = (u32*)&__val; \ + __get_user_asm_word(__v32[0], __src, __err, ""); \ + if (__err) \ + break; \ + __get_user_asm_word(__v32[1], __src+4, __err, ""); \ + break; \ + } \ + default: __err = __get_user_bad(); break; \ + } \ + *(type *)(dst) = __val; \ + if (__err) \ + goto err_label; \ +} while (0) + +#define __put_kernel_nofault(dst, src, type, err_label) \ +do { \ + const type *__pk_ptr = (dst); \ + unsigned long __dst = (unsigned long)__pk_ptr; \ + int __err = 0; \ + type __val = *(type *)src; \ + switch (sizeof(type)) { \ + case 1: __put_user_asm_byte(__val, __dst, __err, ""); break; \ + case 2: __put_user_asm_half(__val, __dst, __err, ""); break; \ + case 4: __put_user_asm_word(__val, __dst, __err, ""); break; \ + case 8: __put_user_asm_dword(__val, __dst, __err, ""); break; \ + default: __err = __put_user_bad(); break; \ + } \ + if (__err) \ + goto err_label; \ +} while (0) #ifdef CONFIG_MMU extern unsigned long __must_check From patchwork Fri Oct 30 15:49:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 11870177 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 7E4D4C00A89 for ; Fri, 30 Oct 2020 15:53:51 +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 BEBFE206CA for ; Fri, 30 Oct 2020 15:53:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="1m+j9Ha4"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="SZu7bKNI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BEBFE206CA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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=tlB12jxtm9JKMUr9WisGRG/jomBDMvKmnx9w9wsR5Vo=; b=1m+j9Ha40qPjZQq59cCwDpewl 0Sk045hENzPvjIRSgGl8u/e42qp/Fkr5faUBCQCFRg+4N3h6wpBaZPNsE0Uma9J8rm1NMVA1vf6o9 yN5KI7pv1K9vco7+DqFci6fkND9jykggFYN+FU7iOu3VJJHiENcxlOvhd0hI3xJvl1RdtE7F5xkM0 5wbWBwVTr5/15TFESJKoqe/dFX7WkukyC+R3f/umAwm+yTeOstWVSRUw/fSedK58ATz4Fc7N6+xwI 3qP0mZT05Vx7NubCs58PBQ3vlA99b5vwrkoThnRi1CAQkFeuv40zRQfJ7yxK96yI6ljfzrDNezm1I /L/aFmuEw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWhK-0003px-BK; Fri, 30 Oct 2020 15:52:14 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kYWf0-00031T-0q for linux-arm-kernel@lists.infradead.org; Fri, 30 Oct 2020 15:50:07 +0000 Received: from localhost.localdomain (HSI-KBW-46-223-126-90.hsi.kabel-badenwuerttemberg.de [46.223.126.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9F908221FA; Fri, 30 Oct 2020 15:49:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604072988; bh=Mb09tzc2RqZDiW5zESZRVaJa8p0JD3B9TZ8nelNX9Bo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SZu7bKNIFA36nZNFMkHJRieZUdefVsM6sCIKUKFyFuezV7w7DHs/SpVUOSI/2QIAX 98hJoI0rSc1QAgCTQ5JdBlxtfOYuJQy9KMPyGcoS7YjyJRO/o8g2/vNLLHYQorVmd/ DTIHUcBk+G0JOOP2pmqgaTbIeBqANHsNeY8rLNlw= From: Arnd Bergmann To: Russell King , Christoph Hellwig Subject: [PATCH 9/9] ARM: uaccess: remove set_fs() implementation Date: Fri, 30 Oct 2020 16:49:19 +0100 Message-Id: <20201030154919.1246645-9-arnd@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201030154919.1246645-1-arnd@kernel.org> References: <20201030154519.1245983-1-arnd@kernel.org> <20201030154919.1246645-1-arnd@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201030_114950_339609_5281DF9D X-CRM114-Status: GOOD ( 24.18 ) 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: linux-arch@vger.kernel.org, arnd@arndb.de, linus.walleij@linaro.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Arnd Bergmann There are no remaining callers of set_fs(), so just remove it along with all associated code that operates on thread_info->addr_limit. There are still further optimizations that can be done: - In get_user(), the address check could be moved entirely into the out of line code, rather than passing a constant as an argument, - I assume the DACR handling can be simplified as we now only change it during user access when CONFIG_CPU_SW_DOMAIN_PAN is set, but not during set_fs(). Signed-off-by: Arnd Bergmann --- arch/arm/Kconfig | 1 - arch/arm/include/asm/ptrace.h | 1 - arch/arm/include/asm/thread_info.h | 4 --- arch/arm/include/asm/uaccess-asm.h | 6 ---- arch/arm/include/asm/uaccess.h | 46 +++--------------------------- arch/arm/kernel/asm-offsets.c | 2 -- arch/arm/kernel/entry-common.S | 9 ------ arch/arm/kernel/process.c | 7 +---- arch/arm/kernel/signal.c | 8 ------ arch/arm/lib/copy_from_user.S | 3 +- arch/arm/lib/copy_to_user.S | 3 +- 11 files changed, 7 insertions(+), 83 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index fe2f17eb2b50..55a8892dd5d8 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -120,7 +120,6 @@ config ARM select PCI_SYSCALL if PCI select PERF_USE_VMALLOC select RTC_LIB - select SET_FS select SYS_SUPPORTS_APM_EMULATION # Above selects are sorted alphabetically; please add new ones # according to that. Thanks. diff --git a/arch/arm/include/asm/ptrace.h b/arch/arm/include/asm/ptrace.h index 91d6b7856be4..93051e2f402c 100644 --- a/arch/arm/include/asm/ptrace.h +++ b/arch/arm/include/asm/ptrace.h @@ -19,7 +19,6 @@ struct pt_regs { struct svc_pt_regs { struct pt_regs regs; u32 dacr; - u32 addr_limit; }; #define to_svc_pt_regs(r) container_of(r, struct svc_pt_regs, regs) diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h index 536b6b979f63..8b705f611216 100644 --- a/arch/arm/include/asm/thread_info.h +++ b/arch/arm/include/asm/thread_info.h @@ -23,8 +23,6 @@ struct task_struct; #include -typedef unsigned long mm_segment_t; - struct cpu_context_save { __u32 r4; __u32 r5; @@ -46,7 +44,6 @@ struct cpu_context_save { struct thread_info { unsigned long flags; /* low level flags */ int preempt_count; /* 0 => preemptable, <0 => bug */ - mm_segment_t addr_limit; /* address limit */ struct task_struct *task; /* main task structure */ __u32 cpu; /* cpu */ __u32 cpu_domain; /* cpu domain */ @@ -72,7 +69,6 @@ struct thread_info { .task = &tsk, \ .flags = 0, \ .preempt_count = INIT_PREEMPT_COUNT, \ - .addr_limit = KERNEL_DS, \ } /* diff --git a/arch/arm/include/asm/uaccess-asm.h b/arch/arm/include/asm/uaccess-asm.h index 907571fd05c6..6451a433912c 100644 --- a/arch/arm/include/asm/uaccess-asm.h +++ b/arch/arm/include/asm/uaccess-asm.h @@ -84,12 +84,8 @@ * if \disable is set. */ .macro uaccess_entry, tsk, tmp0, tmp1, tmp2, disable - ldr \tmp1, [\tsk, #TI_ADDR_LIMIT] - mov \tmp2, #TASK_SIZE - str \tmp2, [\tsk, #TI_ADDR_LIMIT] DACR( mrc p15, 0, \tmp0, c3, c0, 0) DACR( str \tmp0, [sp, #SVC_DACR]) - str \tmp1, [sp, #SVC_ADDR_LIMIT] .if \disable && IS_ENABLED(CONFIG_CPU_SW_DOMAIN_PAN) /* kernel=client, user=no access */ mov \tmp2, #DACR_UACCESS_DISABLE @@ -106,9 +102,7 @@ /* Restore the user access state previously saved by uaccess_entry */ .macro uaccess_exit, tsk, tmp0, tmp1 - ldr \tmp1, [sp, #SVC_ADDR_LIMIT] DACR( ldr \tmp0, [sp, #SVC_DACR]) - str \tmp1, [\tsk, #TI_ADDR_LIMIT] DACR( mcr p15, 0, \tmp0, c3, c0, 0) .endm diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index 4f60638755c4..084d1c07c2d0 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -52,32 +52,8 @@ static __always_inline void uaccess_restore(unsigned int flags) extern int __get_user_bad(void); extern int __put_user_bad(void); -/* - * Note that this is actually 0x1,0000,0000 - */ -#define KERNEL_DS 0x00000000 - #ifdef CONFIG_MMU -#define USER_DS TASK_SIZE -#define get_fs() (current_thread_info()->addr_limit) - -static inline void set_fs(mm_segment_t fs) -{ - current_thread_info()->addr_limit = fs; - - /* - * Prevent a mispredicted conditional call to set_fs from forwarding - * the wrong address limit to access_ok under speculation. - */ - dsb(nsh); - isb(); - - modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER); -} - -#define uaccess_kernel() (get_fs() == KERNEL_DS) - /* * We use 33-bit arithmetic here. Success returns zero, failure returns * addr_limit. We take advantage that addr_limit will be zero for KERNEL_DS, @@ -89,7 +65,7 @@ static inline void set_fs(mm_segment_t fs) __asm__(".syntax unified\n" \ "adds %1, %2, %3; sbcscc %1, %1, %0; movcc %0, #0" \ : "=&r" (flag), "=&r" (roksum) \ - : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \ + : "r" (addr), "Ir" (size), "0" (TASK_SIZE) \ : "cc"); \ flag; }) @@ -120,7 +96,7 @@ static inline void __user *__uaccess_mask_range_ptr(const void __user *ptr, " subshs %1, %1, %2\n" " movlo %0, #0\n" : "+r" (safe_ptr), "=&r" (tmp) - : "r" (size), "r" (current_thread_info()->addr_limit) + : "r" (size), "r" (TASK_SIZE) : "cc"); csdb(); @@ -194,7 +170,7 @@ extern int __get_user_64t_4(void *); #define __get_user_check(x, p) \ ({ \ - unsigned long __limit = current_thread_info()->addr_limit - 1; \ + unsigned long __limit = TASK_SIZE - 1; \ register typeof(*(p)) __user *__p asm("r0") = (p); \ register __inttype(x) __r2 asm("r2"); \ register unsigned long __l asm("r1") = __limit; \ @@ -245,7 +221,7 @@ extern int __put_user_8(void *, unsigned long long); #define __put_user_check(__pu_val, __ptr, __err, __s) \ ({ \ - unsigned long __limit = current_thread_info()->addr_limit - 1; \ + unsigned long __limit = TASK_SIZE - 1; \ register typeof(__pu_val) __r2 asm("r2") = __pu_val; \ register const void __user *__p asm("r0") = __ptr; \ register unsigned long __l asm("r1") = __limit; \ @@ -262,19 +238,8 @@ extern int __put_user_8(void *, unsigned long long); #else /* CONFIG_MMU */ -/* - * uClinux has only one addr space, so has simplified address limits. - */ -#define USER_DS KERNEL_DS - -#define uaccess_kernel() (true) #define __addr_ok(addr) ((void)(addr), 1) #define __range_ok(addr, size) ((void)(addr), 0) -#define get_fs() (KERNEL_DS) - -static inline void set_fs(mm_segment_t fs) -{ -} #define get_user(x, p) __get_user(x, p) #define __put_user_check __put_user_nocheck @@ -283,9 +248,6 @@ static inline void set_fs(mm_segment_t fs) #define access_ok(addr, size) (__range_ok(addr, size) == 0) -#define user_addr_max() \ - (uaccess_kernel() ? ~0UL : get_fs()) - #ifdef CONFIG_CPU_SPECTRE /* * When mitigating Spectre variant 1, it is not worth fixing the non- diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c index 97af6735172b..78f0a25baf2d 100644 --- a/arch/arm/kernel/asm-offsets.c +++ b/arch/arm/kernel/asm-offsets.c @@ -41,7 +41,6 @@ int main(void) BLANK(); DEFINE(TI_FLAGS, offsetof(struct thread_info, flags)); DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count)); - DEFINE(TI_ADDR_LIMIT, offsetof(struct thread_info, addr_limit)); DEFINE(TI_TASK, offsetof(struct thread_info, task)); DEFINE(TI_CPU, offsetof(struct thread_info, cpu)); DEFINE(TI_CPU_DOMAIN, offsetof(struct thread_info, cpu_domain)); @@ -90,7 +89,6 @@ int main(void) DEFINE(S_OLD_R0, offsetof(struct pt_regs, ARM_ORIG_r0)); DEFINE(PT_REGS_SIZE, sizeof(struct pt_regs)); DEFINE(SVC_DACR, offsetof(struct svc_pt_regs, dacr)); - DEFINE(SVC_ADDR_LIMIT, offsetof(struct svc_pt_regs, addr_limit)); DEFINE(SVC_REGS_SIZE, sizeof(struct svc_pt_regs)); BLANK(); DEFINE(SIGFRAME_RC3_OFFSET, offsetof(struct sigframe, retcode[3])); diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 9a76467bbb47..2c0bde14fba6 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -49,9 +49,6 @@ __ret_fast_syscall: UNWIND(.fnstart ) UNWIND(.cantunwind ) disable_irq_notrace @ disable interrupts - ldr r2, [tsk, #TI_ADDR_LIMIT] - cmp r2, #TASK_SIZE - blne addr_limit_check_failed ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK bne fast_work_pending @@ -86,9 +83,6 @@ __ret_fast_syscall: bl do_rseq_syscall #endif disable_irq_notrace @ disable interrupts - ldr r2, [tsk, #TI_ADDR_LIMIT] - cmp r2, #TASK_SIZE - blne addr_limit_check_failed ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK beq no_work_pending @@ -127,9 +121,6 @@ ret_slow_syscall: #endif disable_irq_notrace @ disable interrupts ENTRY(ret_to_user_from_irq) - ldr r2, [tsk, #TI_ADDR_LIMIT] - cmp r2, #TASK_SIZE - blne addr_limit_check_failed ldr r1, [tsk, #TI_FLAGS] tst r1, #_TIF_WORK_MASK bne slow_work_pending diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 8e6ace03e960..28a1a4a9dd77 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -97,7 +97,7 @@ void __show_regs(struct pt_regs *regs) unsigned long flags; char buf[64]; #ifndef CONFIG_CPU_V7M - unsigned int domain, fs; + unsigned int domain; #ifdef CONFIG_CPU_SW_DOMAIN_PAN /* * Get the domain register for the parent context. In user @@ -106,14 +106,11 @@ void __show_regs(struct pt_regs *regs) */ if (user_mode(regs)) { domain = DACR_UACCESS_ENABLE; - fs = get_fs(); } else { domain = to_svc_pt_regs(regs)->dacr; - fs = to_svc_pt_regs(regs)->addr_limit; } #else domain = get_domain(); - fs = get_fs(); #endif #endif @@ -149,8 +146,6 @@ void __show_regs(struct pt_regs *regs) if ((domain & domain_mask(DOMAIN_USER)) == domain_val(DOMAIN_USER, DOMAIN_NOACCESS)) segment = "none"; - else if (fs == KERNEL_DS) - segment = "kernel"; else segment = "user"; diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 585edbfccf6d..e2e4db8fee42 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -709,14 +709,6 @@ struct page *get_signal_page(void) return page; } -/* Defer to generic check */ -asmlinkage void addr_limit_check_failed(void) -{ -#ifdef CONFIG_MMU - addr_limit_user_check(); -#endif -} - #ifdef CONFIG_DEBUG_RSEQ asmlinkage void do_rseq_syscall(struct pt_regs *regs) { diff --git a/arch/arm/lib/copy_from_user.S b/arch/arm/lib/copy_from_user.S index f8016e3db65d..f481ef789a93 100644 --- a/arch/arm/lib/copy_from_user.S +++ b/arch/arm/lib/copy_from_user.S @@ -109,8 +109,7 @@ ENTRY(arm_copy_from_user) #ifdef CONFIG_CPU_SPECTRE - get_thread_info r3 - ldr r3, [r3, #TI_ADDR_LIMIT] + mov r3, #TASK_SIZE uaccess_mask_range_ptr r1, r2, r3, ip #endif diff --git a/arch/arm/lib/copy_to_user.S b/arch/arm/lib/copy_to_user.S index ebfe4cb3d912..215da16c7d6e 100644 --- a/arch/arm/lib/copy_to_user.S +++ b/arch/arm/lib/copy_to_user.S @@ -109,8 +109,7 @@ ENTRY(__copy_to_user_std) WEAK(arm_copy_to_user) #ifdef CONFIG_CPU_SPECTRE - get_thread_info r3 - ldr r3, [r3, #TI_ADDR_LIMIT] + mov r3, #TASK_SIZE uaccess_mask_range_ptr r0, r2, r3, ip #endif