From patchwork Fri Jan 22 14:37:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vincenzo Frascino X-Patchwork-Id: 12039537 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=-16.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AF569C433E0 for ; Fri, 22 Jan 2021 14:39:41 +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 6D38323444 for ; Fri, 22 Jan 2021 14:39:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6D38323444 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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:In-Reply-To:References:List-Owner; bh=6gebjwpucqIyfHIadZiEZl8y8ZOOKIq9OsZqQeDPZQc=; b=ZmI9uVnkcQLDiUTQBPZvQd0WGD iQCOk2qSAJv/xmRlILpPtH3fpP2LAOMpfIldiiyNF3q5f4983mCp90gvcf5YzaObho0yjAJ7y4VWu 1n7urbgJchQzGDJ/w6yVCqeXRJIMirGKx3qC5z8iM9H2WTqeL8aI+/z0guBF0aekKhrc9FQDlM1Fz iY4ZGR1I81L8o7xanMnovN/NjLbFoHI9v3X9Dw8SUIoYnf3eJl927dgxCLRfh97qZSt/4Y6IJSfrX dwznqwJWdutmbaX9q3Gb29+lUt9USb7f67RyhA9plptRBawaTY3cJs/TxT5vCwrbqgYQaQDJwOg2R rMcQ3ZAA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l2xZt-0008L1-1d; Fri, 22 Jan 2021 14:38:21 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l2xZp-0008KJ-OD for linux-arm-kernel@lists.infradead.org; Fri, 22 Jan 2021 14:38:18 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BA21D11B3; Fri, 22 Jan 2021 06:38:16 -0800 (PST) Received: from e119884-lin.cambridge.arm.com (e119884-lin.cambridge.arm.com [10.1.196.72]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id F2DCC3F66E; Fri, 22 Jan 2021 06:38:14 -0800 (PST) From: Vincenzo Frascino To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com Subject: [PATCH v3 0/2] kasan: Fix metadata detection for KASAN_HW_TAGS Date: Fri, 22 Jan 2021 14:37:46 +0000 Message-Id: <20210122143748.50089-1-vincenzo.frascino@arm.com> X-Mailer: git-send-email 2.30.0 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210122_093817_849193_069860FF X-CRM114-Status: GOOD ( 13.09 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , "Paul E . McKenney" , Andrey Konovalov , Naresh Kamboju , Leon Romanovsky , Alexander Potapenko , Catalin Marinas , Andrey Ryabinin , Vincenzo Frascino , Will Deacon , Dmitry Vyukov Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org With the introduction of KASAN_HW_TAGS, kasan_report() currently assumes that every location in memory has valid metadata associated. This is due to the fact that addr_has_metadata() returns always true. As a consequence of this, an invalid address (e.g. NULL pointer address) passed to kasan_report() when KASAN_HW_TAGS is enabled, leads to a kernel panic. Example below, based on arm64: ================================================================== BUG: KASAN: invalid-access in 0x0 Read at addr 0000000000000000 by task swapper/0/1 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Mem abort info: ESR = 0x96000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 ... Call trace: mte_get_mem_tag+0x24/0x40 kasan_report+0x1a4/0x410 alsa_sound_last_init+0x8c/0xa4 do_one_initcall+0x50/0x1b0 kernel_init_freeable+0x1d4/0x23c kernel_init+0x14/0x118 ret_from_fork+0x10/0x34 Code: d65f03c0 9000f021 f9428021 b6cfff61 (d9600000) ---[ end trace 377c8bb45bdd3a1a ]--- hrtimer: interrupt took 48694256 ns note: swapper/0[1] exited with preempt_count 1 Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b SMP: stopping secondary CPUs Kernel Offset: 0x35abaf140000 from 0xffff800010000000 PHYS_OFFSET: 0x40000000 CPU features: 0x0a7e0152,61c0a030 Memory Limit: none ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]--- This series fixes the behavior of addr_has_metadata() that now returns true only when the address is valid. Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Leon Romanovsky Cc: Andrey Konovalov Cc: Catalin Marinas Cc: Will Deacon Cc: Mark Rutland Cc: Paul E. McKenney Cc: Naresh Kamboju Signed-off-by: Vincenzo Frascino Vincenzo Frascino (2): arm64: Improve kernel address detection of __is_lm_address() kasan: Add explicit preconditions to kasan_report() arch/arm64/include/asm/memory.h | 6 ++++-- include/linux/kasan.h | 7 +++++++ mm/kasan/kasan.h | 2 +- 3 files changed, 12 insertions(+), 3 deletions(-)