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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,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 7A0F1C433E3 for ; Wed, 24 Mar 2021 04:06:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4B480619F1 for ; Wed, 24 Mar 2021 04:06:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235189AbhCXEGC (ORCPT ); Wed, 24 Mar 2021 00:06:02 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:56235 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S229981AbhCXEFi (ORCPT ); Wed, 24 Mar 2021 00:05:38 -0400 X-UUID: 4f555892369f483ca5cd0ed9efb7ceed-20210324 X-UUID: 4f555892369f483ca5cd0ed9efb7ceed-20210324 Received: from mtkcas11.mediatek.inc [(172.21.101.40)] by mailgw02.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.14 Build 0819 with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 110564171; Wed, 24 Mar 2021 12:05:34 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs05n1.mediatek.inc (172.21.101.15) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 24 Mar 2021 12:05:32 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Wed, 24 Mar 2021 12:05:32 +0800 From: Lecopzer Chen To: , , , , CC: , , , , , , , , , , , Lecopzer Chen Subject: [PATCH v4 4/5] arm64: kaslr: support randomized module area with KASAN_VMALLOC Date: Wed, 24 Mar 2021 12:05:21 +0800 Message-ID: <20210324040522.15548-5-lecopzer.chen@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20210324040522.15548-1-lecopzer.chen@mediatek.com> References: <20210324040522.15548-1-lecopzer.chen@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After KASAN_VMALLOC works in arm64, we can randomize module region into vmalloc area now. Test: VMALLOC area ffffffc010000000 fffffffdf0000000 before the patch: module_alloc_base/end ffffffc008b80000 ffffffc010000000 after the patch: module_alloc_base/end ffffffdcf4bed000 ffffffc010000000 And the function that insmod some modules is fine. Suggested-by: Ard Biesheuvel Signed-off-by: Lecopzer Chen --- arch/arm64/kernel/kaslr.c | 18 ++++++++++-------- arch/arm64/kernel/module.c | 16 +++++++++------- 2 files changed, 19 insertions(+), 15 deletions(-) diff --git a/arch/arm64/kernel/kaslr.c b/arch/arm64/kernel/kaslr.c index 27f8939deb1b..341342b207f6 100644 --- a/arch/arm64/kernel/kaslr.c +++ b/arch/arm64/kernel/kaslr.c @@ -128,15 +128,17 @@ u64 __init kaslr_early_init(void) /* use the top 16 bits to randomize the linear region */ memstart_offset_seed = seed >> 48; - if (IS_ENABLED(CONFIG_KASAN_GENERIC) || - IS_ENABLED(CONFIG_KASAN_SW_TAGS)) + if (!IS_ENABLED(CONFIG_KASAN_VMALLOC) && + (IS_ENABLED(CONFIG_KASAN_GENERIC) || + IS_ENABLED(CONFIG_KASAN_SW_TAGS))) /* - * KASAN does not expect the module region to intersect the - * vmalloc region, since shadow memory is allocated for each - * module at load time, whereas the vmalloc region is shadowed - * by KASAN zero pages. So keep modules out of the vmalloc - * region if KASAN is enabled, and put the kernel well within - * 4 GB of the module region. + * KASAN without KASAN_VMALLOC does not expect the module region + * to intersect the vmalloc region, since shadow memory is + * allocated for each module at load time, whereas the vmalloc + * region is shadowed by KASAN zero pages. So keep modules + * out of the vmalloc region if KASAN is enabled without + * KASAN_VMALLOC, and put the kernel well within 4 GB of the + * module region. */ return offset % SZ_2G; diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c index fe21e0f06492..b5ec010c481f 100644 --- a/arch/arm64/kernel/module.c +++ b/arch/arm64/kernel/module.c @@ -40,14 +40,16 @@ void *module_alloc(unsigned long size) NUMA_NO_NODE, __builtin_return_address(0)); if (!p && IS_ENABLED(CONFIG_ARM64_MODULE_PLTS) && - !IS_ENABLED(CONFIG_KASAN_GENERIC) && - !IS_ENABLED(CONFIG_KASAN_SW_TAGS)) + (IS_ENABLED(CONFIG_KASAN_VMALLOC) || + (!IS_ENABLED(CONFIG_KASAN_GENERIC) && + !IS_ENABLED(CONFIG_KASAN_SW_TAGS)))) /* - * KASAN can only deal with module allocations being served - * from the reserved module region, since the remainder of - * the vmalloc region is already backed by zero shadow pages, - * and punching holes into it is non-trivial. Since the module - * region is not randomized when KASAN is enabled, it is even + * KASAN without KASAN_VMALLOC can only deal with module + * allocations being served from the reserved module region, + * since the remainder of the vmalloc region is already + * backed by zero shadow pages, and punching holes into it + * is non-trivial. Since the module region is not randomized + * when KASAN is enabled without KASAN_VMALLOC, it is even * less likely that the module region gets exhausted, so we * can simply omit this fallback in that case. */ -- 2.25.1