From mboxrd@z Thu Jan 1 00:00:00 1970 From: Walter Wu Subject: Re: [PATCH] kasan: fix the missing underflow in memmove and memcpy with CONFIG_KASAN_GENERIC=y Date: Tue, 8 Oct 2019 19:02:08 +0800 Message-ID: <1570532528.4686.102.camel@mtksdccf07> References: <1570515358.4686.97.camel@mtksdccf07> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Qian Cai Cc: Dmitry Vyukov , Andrey Ryabinin , Alexander Potapenko , Matthias Brugger , LKML , kasan-dev , Linux-MM , Linux ARM , linux-mediatek@lists.infradead.org, wsd_upstream List-Id: linux-mediatek@lists.infradead.org On Tue, 2019-10-08 at 05:47 -0400, Qian Cai wrote: > > > On Oct 8, 2019, at 2:16 AM, Walter Wu wrote: > > > > It is an undefined behavior to pass a negative numbers to > > memset()/memcpy()/memmove(), so need to be detected by KASAN. > > Why can’t this be detected by UBSAN? I don't know very well in UBSAN, but I try to build ubsan kernel and test a negative number in memset and kmalloc_memmove_invalid_size(), it look like no check. 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=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=no 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 1F858C4360C for ; Tue, 8 Oct 2019 11:02:22 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 E491A206BB for ; Tue, 8 Oct 2019 11:02:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="oS1GsBeF" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E491A206BB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-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=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Date:To:From:Subject:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=yXoJUyknSFzpQ3/6Fi2Ja9YWJW7Xqodkd1IBrH4C0ys=; b=oS1GsBeFIrMDOt BPPEAsxrHkX2vwRT14fwKwt+aKPsLMPk3m1XLUUEve3ioWyakXQFMlcc7M+r+gnwp8M8mmYluzTtg QFeC1rHQh/uKd/zqA1ed/q599Y2rnc4qQKZntUrE+A+JX9yBCSlfPGVYAMC1qllqn8tzWSvvPfOsE 5cWmvcCKEmcBGeoLLyn3Qcacjj/DfrklzpwGHZR0o/xShBMZndvpi+0UkMQk9GxF8sGGRdjtZczTi 3fRGwFCga5LytatJWzuPFvOHHR37xmgWFp9wIIoZcISLEwgI3xzoGsFXEJkv0R49YO2hHOwAPRE1W AGTQml/KfOzeh7oaHr9A==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iHnG1-0003Ea-JZ; Tue, 08 Oct 2019 11:02:21 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.92.2 #3 (Red Hat Linux)) id 1iHnFx-0003Dx-Jx; Tue, 08 Oct 2019 11:02:20 +0000 X-UUID: cd28475709364b57974ae7715b541d6c-20191008 X-UUID: cd28475709364b57974ae7715b541d6c-20191008 Received: from mtkcas68.mediatek.inc [(172.29.94.19)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLS) with ESMTP id 1201304622; Tue, 08 Oct 2019 03:02:14 -0800 Received: from MTKMBS07N2.mediatek.inc (172.21.101.141) by MTKMBS62DR.mediatek.inc (172.29.94.18) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 8 Oct 2019 04:02:08 -0700 Received: from mtkcas08.mediatek.inc (172.21.101.126) by mtkmbs07n2.mediatek.inc (172.21.101.141) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 8 Oct 2019 19:02:07 +0800 Received: from [172.21.84.99] (172.21.84.99) by mtkcas08.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Tue, 8 Oct 2019 19:02:07 +0800 Message-ID: <1570532528.4686.102.camel@mtksdccf07> Subject: Re: [PATCH] kasan: fix the missing underflow in memmove and memcpy with CONFIG_KASAN_GENERIC=y From: Walter Wu To: Qian Cai Date: Tue, 8 Oct 2019 19:02:08 +0800 In-Reply-To: References: <1570515358.4686.97.camel@mtksdccf07> X-Mailer: Evolution 3.2.3-0ubuntu6 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191008_040217_659851_F80754B1 X-CRM114-Status: UNSURE ( 9.32 ) X-CRM114-Notice: Please train this message. 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: wsd_upstream , linux-mediatek@lists.infradead.org, LKML , kasan-dev , Linux-MM , Alexander Potapenko , Linux ARM , Matthias Brugger , Andrey Ryabinin , Dmitry Vyukov Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gVHVlLCAyMDE5LTEwLTA4IGF0IDA1OjQ3IC0wNDAwLCBRaWFuIENhaSB3cm90ZToKPiAKPiA+ IE9uIE9jdCA4LCAyMDE5LCBhdCAyOjE2IEFNLCBXYWx0ZXIgV3UgPHdhbHRlci16aC53dUBtZWRp YXRlay5jb20+IHdyb3RlOgo+ID4gCj4gPiBJdCBpcyBhbiB1bmRlZmluZWQgYmVoYXZpb3IgdG8g cGFzcyBhIG5lZ2F0aXZlIG51bWJlcnMgdG8KPiA+ICAgIG1lbXNldCgpL21lbWNweSgpL21lbW1v dmUoKSwgc28gbmVlZCB0byBiZSBkZXRlY3RlZCBieSBLQVNBTi4KPiAKPiBXaHkgY2Fu4oCZdCB0 aGlzIGJlIGRldGVjdGVkIGJ5IFVCU0FOPwoKSSBkb24ndCBrbm93IHZlcnkgd2VsbCBpbiBVQlNB TiwgYnV0IEkgdHJ5IHRvIGJ1aWxkIHVic2FuIGtlcm5lbCBhbmQKdGVzdCBhIG5lZ2F0aXZlIG51 bWJlciBpbiBtZW1zZXQgYW5kIGttYWxsb2NfbWVtbW92ZV9pbnZhbGlkX3NpemUoKSwgaXQKbG9v ayBsaWtlIG5vIGNoZWNrLgoKCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fCmxpbnV4LWFybS1rZXJuZWwgbWFpbGluZyBsaXN0CmxpbnV4LWFybS1rZXJuZWxA bGlzdHMuaW5mcmFkZWFkLm9yZwpodHRwOi8vbGlzdHMuaW5mcmFkZWFkLm9yZy9tYWlsbWFuL2xp c3RpbmZvL2xpbnV4LWFybS1rZXJuZWwK 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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED, USER_AGENT_SANE_2 autolearn=no 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 468D8ECE58E for ; 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Tue, 8 Oct 2019 11:02:13 +0000 (UTC) X-FDA: 76020328146.30.steel29_4d83fe662323a X-HE-Tag: steel29_4d83fe662323a X-Filterd-Recvd-Size: 2414 Received: from mailgw02.mediatek.com (unknown [210.61.82.184]) by imf15.hostedemail.com (Postfix) with ESMTP for ; Tue, 8 Oct 2019 11:02:12 +0000 (UTC) X-UUID: 814ed363ca79487d969aaa2a5840218c-20191008 X-UUID: 814ed363ca79487d969aaa2a5840218c-20191008 Received: from mtkcas07.mediatek.inc [(172.21.101.84)] by mailgw02.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.10 Build 0809 with TLS) with ESMTP id 2095119737; Tue, 08 Oct 2019 19:02:09 +0800 Received: from mtkcas08.mediatek.inc (172.21.101.126) by mtkmbs07n2.mediatek.inc (172.21.101.141) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 8 Oct 2019 19:02:07 +0800 Received: from [172.21.84.99] (172.21.84.99) by mtkcas08.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Tue, 8 Oct 2019 19:02:07 +0800 Message-ID: <1570532528.4686.102.camel@mtksdccf07> Subject: Re: [PATCH] kasan: fix the missing underflow in memmove and memcpy with CONFIG_KASAN_GENERIC=y From: Walter Wu To: Qian Cai CC: Dmitry Vyukov , Andrey Ryabinin , Alexander Potapenko , Matthias Brugger , LKML , kasan-dev , Linux-MM , Linux ARM , , wsd_upstream Date: Tue, 8 Oct 2019 19:02:08 +0800 In-Reply-To: References: <1570515358.4686.97.camel@mtksdccf07> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 MIME-Version: 1.0 X-MTK: N Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.261325, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, 2019-10-08 at 05:47 -0400, Qian Cai wrote: >=20 > > On Oct 8, 2019, at 2:16 AM, Walter Wu wro= te: > >=20 > > It is an undefined behavior to pass a negative numbers to > > memset()/memcpy()/memmove(), so need to be detected by KASAN. >=20 > Why can=E2=80=99t this be detected by UBSAN? I don't know very well in UBSAN, but I try to build ubsan kernel and test a negative number in memset and kmalloc_memmove_invalid_size(), it look like no check.