From patchwork Tue Nov 13 05:49:10 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sasha Levin X-Patchwork-Id: 150901 Delivered-To: patch@linaro.org Received: by 2002:a2e:299d:0:0:0:0:0 with SMTP id p29-v6csp4004594ljp; Mon, 12 Nov 2018 21:50:02 -0800 (PST) X-Google-Smtp-Source: AJdET5eezex7dV3x5HMccNHTd2qlrlhVngKKk6O3q0lCRCvl36yB/z/FE7Bk5ookDxCajHtsjrgn X-Received: by 2002:a62:2095:: with SMTP id m21-v6mr828780pfj.32.1542088202338; Mon, 12 Nov 2018 21:50:02 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1542088202; cv=none; d=google.com; s=arc-20160816; b=fxNR4XXU680tLHK5XvnRQSKvR1ox4EQ53HgU3YN8br+ai/sRVtYB3M8G2ExRLt0gLz d/cGvIYBg6Y5vGD4+jvXlu96wp2Z1GuZPsablU8NjIyDDp4Z+YCZO7hLULm24QYvRpg0 CZSHsT/H8HNl9HKKjBZ0MBH6ZjB7tBODHTZtZMkWkyE6d4MWeiLhGKViNcawZC50gPe/ C/MjwdjVj8R1g4z5X5tL7ld+l6sEWr1PxpYepSwXtGcqEreiS0PuzHBMRCKIAHuJV8bw 0XHRxYMdFQzNDfrI3sABzamBddf7CtaXKNiZjev4qQGOBdDBdr0Zdk/10oKJkXx5jNeb O/Yg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from:dkim-signature; bh=0Ivny22atPKP7r09S6eOWAUUxpSyDbfuH38df4pm6AE=; b=acr6YsgI/CwAbKVr2A/Z/byQcXqUaJqAC7qRdOXfXoLGYSkj5g1i6lc7sNxiHgenMc v5rRcHEeCoROKG3jbYC6OYvLOznDdNM51zD1b0lNcmGyvQPGgyW2jk5eDf7wVCQ9kAYy KPZ7w23xJgDAqANfdxuGFkBeAt6+12XOTMYdH25Qrqtu77d2qhOXOtGSFiK88/wEiQrp bEdYd31CM32jF8GS9kA46Dc2DdVubotEbZFRAJaFqxKcUrCWIWfzuO/DxQOpEeuNbWTK tWdg7NNit5WTlRPEeDg4JCDWkT4UGvR/5z9smz+UAzkiiyypVFElZcmLMI4j+zQERjvj EGKA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b="vwZ9/Xvo"; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id q8-v6si19695336pgc.347.2018.11.12.21.50.02; Mon, 12 Nov 2018 21:50:02 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b="vwZ9/Xvo"; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730884AbeKMPqV (ORCPT + 32 others); Tue, 13 Nov 2018 10:46:21 -0500 Received: from mail.kernel.org ([198.145.29.99]:59886 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727475AbeKMPqU (ORCPT ); Tue, 13 Nov 2018 10:46:20 -0500 Received: from sasha-vm.mshome.net (unknown [64.114.255.114]) (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 1E28C2250F; Tue, 13 Nov 2018 05:49:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542088193; bh=r2uAgtl/FPWvBkzUCbhQ0Wz2OgqudjzPYkzWiYxK12c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vwZ9/XvohsNUjq4dDLkpWVaAdwxR/qZkoUeO7j8vSU0TerV3QvgvxVjj2Z2I1046p ytOhzwYD2YRRM/61UOi68pDUyhAUiEsJrnit9DsyMI+FtaNpVwoKTP/8LRURcvsNAr ZYH9lDlVOrcVoY0ikFUG6Osmklr447XiBD+/itpQ= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Anders Roxell , Catalin Marinas , Sasha Levin Subject: [PATCH AUTOSEL 4.19 04/44] arm64: kprobe: make page to RO mode when allocate it Date: Tue, 13 Nov 2018 00:49:10 -0500 Message-Id: <20181113054950.77898-4-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181113054950.77898-1-sashal@kernel.org> References: <20181113054950.77898-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Anders Roxell [ Upstream commit 966866892cf89d606544bca22d584ba2ef9ec208 ] Commit 1404d6f13e47 ("arm64: dump: Add checking for writable and exectuable pages") has successfully identified code that leaves a page with W+X permissions. [ 3.245140] arm64/mm: Found insecure W+X mapping at address (____ptrval____)/0xffff000000d90000 [ 3.245771] WARNING: CPU: 0 PID: 1 at ../arch/arm64/mm/dump.c:232 note_page+0x410/0x420 [ 3.246141] Modules linked in: [ 3.246653] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5-next-20180928-00001-ge70ae259b853-dirty #62 [ 3.247008] Hardware name: linux,dummy-virt (DT) [ 3.247347] pstate: 80000005 (Nzcv daif -PAN -UAO) [ 3.247623] pc : note_page+0x410/0x420 [ 3.247898] lr : note_page+0x410/0x420 [ 3.248071] sp : ffff00000804bcd0 [ 3.248254] x29: ffff00000804bcd0 x28: ffff000009274000 [ 3.248578] x27: ffff00000921a000 x26: ffff80007dfff000 [ 3.248845] x25: ffff0000093f5000 x24: ffff000009526f6a [ 3.249109] x23: 0000000000000004 x22: ffff000000d91000 [ 3.249396] x21: ffff000000d90000 x20: 0000000000000000 [ 3.249661] x19: ffff00000804bde8 x18: 0000000000000400 [ 3.249924] x17: 0000000000000000 x16: 0000000000000000 [ 3.250271] x15: ffffffffffffffff x14: 295f5f5f5f6c6176 [ 3.250594] x13: 7274705f5f5f5f28 x12: 2073736572646461 [ 3.250941] x11: 20746120676e6970 x10: 70616d20582b5720 [ 3.251252] x9 : 6572756365736e69 x8 : 3039643030303030 [ 3.251519] x7 : 306666666678302f x6 : ffff0000095467b2 [ 3.251802] x5 : 0000000000000000 x4 : 0000000000000000 [ 3.252060] x3 : 0000000000000000 x2 : ffffffffffffffff [ 3.252323] x1 : 4d151327adc50b00 x0 : 0000000000000000 [ 3.252664] Call trace: [ 3.252953] note_page+0x410/0x420 [ 3.253186] walk_pgd+0x12c/0x238 [ 3.253417] ptdump_check_wx+0x68/0xf8 [ 3.253637] mark_rodata_ro+0x68/0x98 [ 3.253847] kernel_init+0x38/0x160 [ 3.254103] ret_from_fork+0x10/0x18 kprobes allocates a writable executable page with module_alloc() in order to store executable code. Reworked to that when allocate a page it sets mode RO. Inspired by commit 63fef14fc98a ("kprobes/x86: Make insn buffer always ROX and use text_poke()"). Suggested-by: Arnd Bergmann Suggested-by: Ard Biesheuvel Acked-by: Will Deacon Acked-by: Masami Hiramatsu Reviewed-by: Laura Abbott Signed-off-by: Anders Roxell [catalin.marinas@arm.com: removed unnecessary casts] Signed-off-by: Catalin Marinas Signed-off-by: Sasha Levin --- arch/arm64/kernel/probes/kprobes.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) -- 2.17.1 diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index e78c3ef04d95..b5a367d4bba6 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -23,7 +23,9 @@ #include #include #include +#include #include +#include #include #include #include @@ -42,10 +44,21 @@ DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); static void __kprobes post_kprobe_handler(struct kprobe_ctlblk *, struct pt_regs *); +static int __kprobes patch_text(kprobe_opcode_t *addr, u32 opcode) +{ + void *addrs[1]; + u32 insns[1]; + + addrs[0] = addr; + insns[0] = opcode; + + return aarch64_insn_patch_text(addrs, insns, 1); +} + static void __kprobes arch_prepare_ss_slot(struct kprobe *p) { /* prepare insn slot */ - p->ainsn.api.insn[0] = cpu_to_le32(p->opcode); + patch_text(p->ainsn.api.insn, p->opcode); flush_icache_range((uintptr_t) (p->ainsn.api.insn), (uintptr_t) (p->ainsn.api.insn) + @@ -118,15 +131,15 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) return 0; } -static int __kprobes patch_text(kprobe_opcode_t *addr, u32 opcode) +void *alloc_insn_page(void) { - void *addrs[1]; - u32 insns[1]; + void *page; - addrs[0] = (void *)addr; - insns[0] = (u32)opcode; + page = vmalloc_exec(PAGE_SIZE); + if (page) + set_memory_ro((unsigned long)page, 1); - return aarch64_insn_patch_text(addrs, insns, 1); + return page; } /* arm kprobe: install breakpoint in text */