From patchwork Fri Mar 18 03:40:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?S3Vhbi1ZaW5nIExlZSAo5p2O5Yag56mOKQ==?= X-Patchwork-Id: 12784855 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 487D7C433F5 for ; Fri, 18 Mar 2022 03:49:08 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CACC18D0002; Thu, 17 Mar 2022 23:49:07 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C5BE38D0001; Thu, 17 Mar 2022 23:49:07 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B23A88D0002; Thu, 17 Mar 2022 23:49:07 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0102.hostedemail.com [216.40.44.102]) by kanga.kvack.org (Postfix) with ESMTP id 9FAD18D0001 for ; Thu, 17 Mar 2022 23:49:07 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 4C0848249980 for ; Fri, 18 Mar 2022 03:49:07 +0000 (UTC) X-FDA: 79256126334.16.15DEA6F Received: from mailgw01.mediatek.com (mailgw01.mediatek.com [216.200.240.184]) by imf05.hostedemail.com (Postfix) with ESMTP id E90D2100022 for ; Fri, 18 Mar 2022 03:49:05 +0000 (UTC) X-UUID: 21faa62d4c6941f1b8e4a35c81bf8be7-20220317 X-UUID: 21faa62d4c6941f1b8e4a35c81bf8be7-20220317 Received: from mtkcas66.mediatek.inc [(172.29.193.44)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1398488182; Thu, 17 Mar 2022 20:48:59 -0700 Received: from mtkmbs10n1.mediatek.inc (172.21.101.34) by MTKMBS62N2.mediatek.inc (172.29.193.42) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 17 Mar 2022 20:40:58 -0700 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs10n1.mediatek.inc (172.21.101.34) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.15; Fri, 18 Mar 2022 11:40:56 +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; Fri, 18 Mar 2022 11:40:56 +0800 From: Kuan-Ying Lee To: Catalin Marinas , Andrew Morton , Matthias Brugger CC: , , , Kuan-Ying Lee , , , , Subject: [PATCH] mm/kmemleak: Reset tag when compare object pointer Date: Fri, 18 Mar 2022 11:40:48 +0800 Message-ID: <20220318034051.30687-1-Kuan-Ying.Lee@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 X-MTK: N X-Rspamd-Queue-Id: E90D2100022 X-Rspam-User: Authentication-Results: imf05.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=mediatek.com; spf=pass (imf05.hostedemail.com: domain of kuan-ying.lee@mediatek.com designates 216.200.240.184 as permitted sender) smtp.mailfrom=kuan-ying.lee@mediatek.com X-Stat-Signature: dp97iruaefxtzsb6uz9iwabkhdxjdb5e X-Rspamd-Server: rspam04 X-HE-Tag: 1647575345-914260 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: When we use HW-tag based kasan and enable vmalloc support, we hit the following bug. It is due to comparison between tagged object and non-tagged pointer. We need to reset the kasan tag when we need to compare tagged object and non-tagged pointer. [ 7.690429][T400001] init: kmemleak: [name:kmemleak&]Scan area larger than object 0xffffffe77076f440 [ 7.691762][T400001] init: CPU: 4 PID: 1 Comm: init Tainted: G S W 5.15.25-android13-0-g5cacf919c2bc #1 [ 7.693218][T400001] init: Hardware name: MT6983(ENG) (DT) [ 7.693983][T400001] init: Call trace: [ 7.694508][T400001] init: dump_backtrace.cfi_jt+0x0/0x8 [ 7.695272][T400001] init: dump_stack_lvl+0xac/0x120 [ 7.695985][T400001] init: add_scan_area+0xc4/0x244 [ 7.696685][T400001] init: kmemleak_scan_area+0x40/0x9c [ 7.697428][T400001] init: layout_and_allocate+0x1e8/0x288 [ 7.698211][T400001] init: load_module+0x2c8/0xf00 [ 7.698895][T400001] init: __se_sys_finit_module+0x190/0x1d0 [ 7.699701][T400001] init: __arm64_sys_finit_module+0x20/0x30 [ 7.700517][T400001] init: invoke_syscall+0x60/0x170 [ 7.701225][T400001] init: el0_svc_common+0xc8/0x114 [ 7.701933][T400001] init: do_el0_svc+0x28/0xa0 [ 7.702580][T400001] init: el0_svc+0x60/0xf8 [ 7.703196][T400001] init: el0t_64_sync_handler+0x88/0xec [ 7.703964][T400001] init: el0t_64_sync+0x1b4/0x1b8 [ 7.704658][T400001] init: kmemleak: [name:kmemleak&]Object 0xf5ffffe77076b000 (size 32768): [ 7.705824][T400001] init: kmemleak: [name:kmemleak&] comm "init", pid 1, jiffies 4294894197 [ 7.707002][T400001] init: kmemleak: [name:kmemleak&] min_count = 0 [ 7.707886][T400001] init: kmemleak: [name:kmemleak&] count = 0 [ 7.708718][T400001] init: kmemleak: [name:kmemleak&] flags = 0x1 [ 7.709574][T400001] init: kmemleak: [name:kmemleak&] checksum = 0 [ 7.710440][T400001] init: kmemleak: [name:kmemleak&] backtrace: [ 7.711284][T400001] init: module_alloc+0x9c/0x120 [ 7.712015][T400001] init: move_module+0x34/0x19c [ 7.712735][T400001] init: layout_and_allocate+0x1c4/0x288 [ 7.713561][T400001] init: load_module+0x2c8/0xf00 [ 7.714291][T400001] init: __se_sys_finit_module+0x190/0x1d0 [ 7.715142][T400001] init: __arm64_sys_finit_module+0x20/0x30 [ 7.716004][T400001] init: invoke_syscall+0x60/0x170 [ 7.716758][T400001] init: el0_svc_common+0xc8/0x114 [ 7.717512][T400001] init: do_el0_svc+0x28/0xa0 [ 7.718207][T400001] init: el0_svc+0x60/0xf8 [ 7.718869][T400001] init: el0t_64_sync_handler+0x88/0xec [ 7.719683][T400001] init: el0t_64_sync+0x1b4/0x1b8 Signed-off-by: Kuan-Ying Lee Reviewed-by: Catalin Marinas --- mm/kmemleak.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/mm/kmemleak.c b/mm/kmemleak.c index 7580baa76af1..acd7cbb82e16 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -796,6 +796,8 @@ static void add_scan_area(unsigned long ptr, size_t size, gfp_t gfp) unsigned long flags; struct kmemleak_object *object; struct kmemleak_scan_area *area = NULL; + unsigned long untagged_ptr; + unsigned long untagged_objp; object = find_and_get_object(ptr, 1); if (!object) { @@ -804,6 +806,9 @@ static void add_scan_area(unsigned long ptr, size_t size, gfp_t gfp) return; } + untagged_ptr = (unsigned long)kasan_reset_tag((void *)ptr); + untagged_objp = (unsigned long)kasan_reset_tag((void *)object->pointer); + if (scan_area_cache) area = kmem_cache_alloc(scan_area_cache, gfp_kmemleak_mask(gfp)); @@ -815,8 +820,8 @@ static void add_scan_area(unsigned long ptr, size_t size, gfp_t gfp) goto out_unlock; } if (size == SIZE_MAX) { - size = object->pointer + object->size - ptr; - } else if (ptr + size > object->pointer + object->size) { + size = untagged_objp + object->size - untagged_ptr; + } else if (untagged_ptr + size > untagged_objp + object->size) { kmemleak_warn("Scan area larger than object 0x%08lx\n", ptr); dump_object_info(object); kmem_cache_free(scan_area_cache, area);