From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C44A6C56202 for ; Sun, 8 Nov 2020 05:18:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 84C7822253 for ; Sun, 8 Nov 2020 05:18:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=arista.com header.i=@arista.com header.b="PVI6MSZp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728660AbgKHFSH (ORCPT ); Sun, 8 Nov 2020 00:18:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37820 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728511AbgKHFR4 (ORCPT ); Sun, 8 Nov 2020 00:17:56 -0500 Received: from mail-wr1-x443.google.com (mail-wr1-x443.google.com [IPv6:2a00:1450:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A0C2CC0617A7 for ; Sat, 7 Nov 2020 21:17:54 -0800 (PST) Received: by mail-wr1-x443.google.com with SMTP id b8so5341783wrn.0 for ; Sat, 07 Nov 2020 21:17:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=googlenew; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=pBL188vkiayO3VIBgbN+Ii9TM86j5vNl1BGzj2vUwqc=; b=PVI6MSZpXxnLZWJI4lDn/LyVHxFO2Zyi64Y1ld1+ILDvmM7lwv2qb+9kJV+UESJlbL Eb0AsAmtACwOCRWl+nhAeGBOsdbU1jbbiagqjMtcYeeseUxYmwtH1giDcWn2FCTu/+RV HMP6Q+OsXSN/XCWQ0fHxfSVijdlVZ9RP2AJKEANqWrCHEjbrkuS9Pt7OMXExQEuAE/+2 nN2pzfCH2SpBg0EzqtTb5ZXnB8oxpwHMdq6ZoWaTjO7GZcgLhoxQFfDTf9AFe7t7LyNd 5mgHdd/6q4mlJyoDrYS4A4Zbvaql2TH3v354/lPLxQLM3JRmY/rBZeDZ+fhcMINOIT6P ZIcQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=pBL188vkiayO3VIBgbN+Ii9TM86j5vNl1BGzj2vUwqc=; b=YU/kWXc1CSoNChiob8kUsSs6it1HEg8uKuDMFY6F1d4p7ucbCjb6gj7znpWbycezK8 gS5LNuu+ZD+d1foAoc2WQcuUuugU4NLZ0fcVcUcPbTrQ6MrvZakUU6x7pXrecfIDWIlj 2lpoqvAeT4qJtaEdACFjx3JpjfecPGRqv7JbHbeRj4DGB8dH6MbVE7X8PsrUJOsJlGOp KOxAHCAd27PgMDHvS+AyMuKFlk9kA0q6QMx9axisdBdv+rFHYPzhUfgwY1H98/onoRkD 8aHqUKSGq6tQp0Dko6IEHUNmduV578YpQJOkjyzQn/uyDAPZy4eMVyQeltn0EQSQisnZ i4hw== X-Gm-Message-State: AOAM5306AruP4ETU53OHPW0HFkUF3uaW6R3MDDx0qA/hj5SpImNF6w3A qGnElqWEl6aNLhwCBqoXXIP+edkcRTX15IRG X-Google-Smtp-Source: ABdhPJzs19ieFd4H3IWh+l6ae3ehpGTNk34g1y/g0qPAO16wTEnq3JSuqinEVqqe8Gl99IOx8/ImgQ== X-Received: by 2002:adf:a2c2:: with SMTP id t2mr11326036wra.54.1604812673142; Sat, 07 Nov 2020 21:17:53 -0800 (PST) Received: from localhost.localdomain ([2a02:8084:e84:2480:228:f8ff:fe6f:83a8]) by smtp.gmail.com with ESMTPSA id r10sm8378462wmg.16.2020.11.07.21.17.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 07 Nov 2020 21:17:52 -0800 (PST) From: Dmitry Safonov To: linux-kernel@vger.kernel.org Cc: Dmitry Safonov <0x7f454c46@gmail.com>, Dmitry Safonov , Alexander Viro , Andrew Morton , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Christophe Leroy , Guo Ren , "H. Peter Anvin" , Ingo Molnar , Oleg Nesterov , Russell King , Thomas Bogendoerfer , Thomas Gleixner , Vincenzo Frascino , Will Deacon , x86@kernel.org Subject: [PATCH 15/19] x86/vdso: Migrate to user_landing Date: Sun, 8 Nov 2020 05:17:25 +0000 Message-Id: <20201108051730.2042693-16-dima@arista.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201108051730.2042693-1-dima@arista.com> References: <20201108051730.2042693-1-dima@arista.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Generic way to track the land vma area. As a bonus, after unmapping vdso, kernel won't try to land on its previous position. Signed-off-by: Dmitry Safonov --- arch/x86/Kconfig | 1 + arch/x86/entry/common.c | 3 ++- arch/x86/entry/vdso/vma.c | 9 ++++----- arch/x86/ia32/ia32_signal.c | 4 ++-- arch/x86/include/asm/mmu.h | 1 - arch/x86/include/asm/vdso.h | 2 +- arch/x86/kernel/signal.c | 4 ++-- 7 files changed, 12 insertions(+), 12 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index b068f949d2e4..2449844ef0e9 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -84,6 +84,7 @@ config X86 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE select ARCH_HAS_SYSCALL_WRAPPER select ARCH_HAS_UBSAN_SANITIZE_ALL + select ARCH_HAS_USER_LANDING select ARCH_HAS_DEBUG_WX select ARCH_HAVE_NMI_SAFE_CMPXCHG select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 1be1bdbe55d4..1a3f795af331 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -151,9 +151,10 @@ __visible noinstr long do_fast_syscall_32(struct pt_regs *regs) * Called using the internal vDSO SYSENTER/SYSCALL32 calling * convention. Adjust regs so it looks like we entered using int80. */ - landing_pad = (unsigned long)current->mm->context.vdso + + landing_pad = (unsigned long)current->mm->user_landing + vdso_image_32.sym_int80_landing_pad; + /* * SYSENTER loses EIP, and even SYSCALL32 needs us to skip forward * so that 'regs->ip -= 2' lands back on an int $0x80 instruction. diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c index 65780a0164e3..2c426997a7a4 100644 --- a/arch/x86/entry/vdso/vma.c +++ b/arch/x86/entry/vdso/vma.c @@ -77,7 +77,7 @@ static void vdso_fix_landing(const struct vdso_image *image, struct pt_regs *regs = current_pt_regs(); unsigned long vdso_land = image->sym_int80_landing_pad; unsigned long old_land_addr = vdso_land + - (unsigned long)current->mm->context.vdso; + (unsigned long)current->mm->user_landing; /* Fixing userspace landing - look at do_fast_syscall_32 */ if (regs->ip == old_land_addr) @@ -92,7 +92,6 @@ static void vdso_mremap(const struct vm_special_mapping *sm, const struct vdso_image *image = current->mm->context.vdso_image; vdso_fix_landing(image, new_vma); - current->mm->context.vdso = (void __user *)new_vma->vm_start; } #ifdef CONFIG_TIME_NS @@ -287,7 +286,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr, ret = PTR_ERR(vma); do_munmap(mm, text_start, image->size, NULL); } else { - current->mm->context.vdso = (void __user *)text_start; + current->mm->user_landing = (void __user *)text_start; current->mm->context.vdso_image = image; *sysinfo_ehdr = text_start; } @@ -362,8 +361,8 @@ int map_vdso_once(const struct vdso_image *image, unsigned long addr) * Check if we have already mapped vdso blob - fail to prevent * abusing from userspace install_speciall_mapping, which may * not do accounting and rlimit right. - * We could search vma near context.vdso, but it's a slowpath, - * so let's explicitly check all VMAs to be completely sure. + * It's a slowpath, let's explicitly check all VMAs to be + * completely sure. */ for (vma = mm->mmap; vma; vma = vma->vm_next) { if (vma_is_special_mapping(vma, &vdso_mapping) || diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index f87ed1d53938..fb84c0fcdc4e 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -256,7 +256,7 @@ int ia32_setup_frame(int sig, struct ksignal *ksig, } else { /* Return stub is in 32bit vsyscall page */ if (current_has_vdso_image_32()) - restorer = current->mm->context.vdso + + restorer = current->mm->user_landing + vdso_image_32.sym___kernel_sigreturn; else restorer = &frame->retcode; @@ -337,7 +337,7 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig, if (ksig->ka.sa.sa_flags & SA_RESTORER) restorer = ksig->ka.sa.sa_restorer; else if (current_has_vdso_image_32()) - restorer = current->mm->context.vdso + + restorer = current->mm->user_landing + vdso_image_32.sym___kernel_rt_sigreturn; else restorer = &frame->retcode; diff --git a/arch/x86/include/asm/mmu.h b/arch/x86/include/asm/mmu.h index 5d7494631ea9..7bd10e6b8386 100644 --- a/arch/x86/include/asm/mmu.h +++ b/arch/x86/include/asm/mmu.h @@ -43,7 +43,6 @@ typedef struct { #endif struct mutex lock; - void __user *vdso; /* vdso base address */ const struct vdso_image *vdso_image; /* vdso image in use */ atomic_t perf_rdpmc_allowed; /* nonzero if rdpmc is allowed */ diff --git a/arch/x86/include/asm/vdso.h b/arch/x86/include/asm/vdso.h index a19e0a7bae2d..735ad9e563e1 100644 --- a/arch/x86/include/asm/vdso.h +++ b/arch/x86/include/asm/vdso.h @@ -42,7 +42,7 @@ extern const struct vdso_image vdso_image_32; #define current_has_vdso_image_32() \ likely(current->mm->context.vdso_image == &vdso_image_32 && \ - !!current->mm->context.vdso) + (unsigned long)current->mm->user_landing != UNMAPPED_USER_LANDING) #endif extern void __init init_vdso_image(const struct vdso_image *image); diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 6fed2e523e0a..b18e6dd0a574 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -320,7 +320,7 @@ __setup_frame(int sig, struct ksignal *ksig, sigset_t *set, if (ksig->ka.sa.sa_flags & SA_RESTORER) restorer = ksig->ka.sa.sa_restorer; else if (current_has_vdso_image_32()) - restorer = current->mm->context.vdso + + restorer = current->mm->user_landing + vdso_image_32.sym___kernel_sigreturn; else restorer = &frame->retcode; @@ -382,7 +382,7 @@ static int __setup_rt_frame(int sig, struct ksignal *ksig, if (ksig->ka.sa.sa_flags & SA_RESTORER) restorer = ksig->ka.sa.sa_restorer; else if (current_has_vdso_image_32()) - restorer = current->mm->context.vdso + + restorer = current->mm->user_landing + vdso_image_32.sym___kernel_rt_sigreturn; else restorer = &frame->retcode; -- 2.28.0