From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: [4.17,34/70] x86/MCE: Fix stack out-of-bounds write in mce-inject.c: Flags_read() From: Greg Kroah-Hartman Message-Id: <20180624142742.620481125@linuxfoundation.org> Date: Sun, 24 Jun 2018 23:22:26 +0800 To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Vyukov , Tony Luck , Borislav Petkov , Thomas Gleixner , linux-edac List-ID: NC4xNy1zdGFibGUgcmV2aWV3IHBhdGNoLiAgSWYgYW55b25lIGhhcyBhbnkgb2JqZWN0aW9ucywg cGxlYXNlIGxldCBtZSBrbm93LgoKLS0tLS0tLS0tLS0tLS0tLS0tCgpGcm9tOiBUb255IEx1Y2sg PHRvbnkubHVja0BpbnRlbC5jb20+Cgpjb21taXQgOTg1Yzc4ZDNmZjhlOWM3NDQ1MGZhMmJiMDhl YjU1ZTY4MGQ5OTljYSB1cHN0cmVhbS4KCkVhY2ggb2YgdGhlIHN0cmluZ3MgdGhhdCB3ZSB3YW50 IHRvIHB1dCBpbnRvIHRoZSBidWZbTUFYX0ZMQUdfT1BUX1NJWkVdCmluIGZsYWdzX3JlYWQoKSBp cyB0d28gY2hhcmFjdGVycyBsb25nLiBCdXQgdGhlIHNwcmludGYoKSBhZGRzCmEgdHJhaWxpbmcg bmV3bGluZSBhbmQgd2lsbCBhZGQgYSB0ZXJtaW5hdGluZyBOVUwgYnl0ZS4gU28KTUFYX0ZMQUdf T1BUX1NJWkUgbmVlZHMgdG8gYmUgNC4KCnNwcmludGYoKSBjYWxscyB2c25wcmludGYoKSBhbmQg KnRoYXQqIGRvZXMgcmV0dXJuOgoKIiAqIFRoZSByZXR1cm4gdmFsdWUgaXMgdGhlIG51bWJlciBv ZiBjaGFyYWN0ZXJzIHdoaWNoIHdvdWxkCiAqIGJlIGdlbmVyYXRlZCBmb3IgdGhlIGdpdmVuIGlu cHV0LCBleGNsdWRpbmcgdGhlIHRyYWlsaW5nCiAqICdcMCcsIGFzIHBlciBJU08gQzk5LiIKCk5v dGUgdGhlICJleGNsdWRpbmciLgoKUmVwb3J0ZWQtYnk6IERtaXRyeSBWeXVrb3YgPGR2eXVrb3ZA Z29vZ2xlLmNvbT4KU2lnbmVkLW9mZi1ieTogVG9ueSBMdWNrIDx0b255Lmx1Y2tAaW50ZWwuY29t PgpTaWduZWQtb2ZmLWJ5OiBCb3Jpc2xhdiBQZXRrb3YgPGJwQHN1c2UuZGU+ClNpZ25lZC1vZmYt Ynk6IFRob21hcyBHbGVpeG5lciA8dGdseEBsaW51dHJvbml4LmRlPgpDYzogc3RhYmxlQHZnZXIu a2VybmVsLm9yZwpDYzogbGludXgtZWRhYyA8bGludXgtZWRhY0B2Z2VyLmtlcm5lbC5vcmc+Ckxp bms6IGh0dHA6Ly9sa21sLmtlcm5lbC5vcmcvci8yMDE4MDQyNzE2MzcwNy5rdGFpeXN2YmszeWhr NHdtQGFnbHVjay1kZXNrClNpZ25lZC1vZmYtYnk6IEdyZWcgS3JvYWgtSGFydG1hbiA8Z3JlZ2to QGxpbnV4Zm91bmRhdGlvbi5vcmc+Ci0tLQogYXJjaC94ODYva2VybmVsL2NwdS9tY2hlY2svbWNl LWluamVjdC5jIHwgICAgMiArLQogMSBmaWxlIGNoYW5nZWQsIDEgaW5zZXJ0aW9uKCspLCAxIGRl bGV0aW9uKC0pCgoKCi0tClRvIHVuc3Vic2NyaWJlIGZyb20gdGhpcyBsaXN0OiBzZW5kIHRoZSBs aW5lICJ1bnN1YnNjcmliZSBsaW51eC1lZGFjIiBpbgp0aGUgYm9keSBvZiBhIG1lc3NhZ2UgdG8g bWFqb3Jkb21vQHZnZXIua2VybmVsLm9yZwpNb3JlIG1ham9yZG9tbyBpbmZvIGF0ICBodHRwOi8v dmdlci5rZXJuZWwub3JnL21ham9yZG9tby1pbmZvLmh0bWwKCi0tLSBhL2FyY2gveDg2L2tlcm5l bC9jcHUvbWNoZWNrL21jZS1pbmplY3QuYworKysgYi9hcmNoL3g4Ni9rZXJuZWwvY3B1L21jaGVj ay9tY2UtaW5qZWN0LmMKQEAgLTQ4LDcgKzQ4LDcgQEAgc3RhdGljIHN0cnVjdCBkZW50cnkgKmRm c19pbmo7CiAKIHN0YXRpYyB1OCBuX2JhbmtzOwogCi0jZGVmaW5lIE1BWF9GTEFHX09QVF9TSVpF CTMKKyNkZWZpbmUgTUFYX0ZMQUdfT1BUX1NJWkUJNAogI2RlZmluZSBOQkNGRwkJCTB4NDQKIAog ZW51bSBpbmplY3Rpb25fdHlwZSB7Cg== 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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 39277C43142 for ; Sun, 24 Jun 2018 15:43:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 005F425090 for ; Sun, 24 Jun 2018 15:43:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 005F425090 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756151AbeFXPnT (ORCPT ); Sun, 24 Jun 2018 11:43:19 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60118 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755321AbeFXPnQ (ORCPT ); Sun, 24 Jun 2018 11:43:16 -0400 Received: from localhost (li1825-44.members.linode.com [172.104.248.44]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 9CCCF2C; Sun, 24 Jun 2018 15:43:14 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Vyukov , Tony Luck , Borislav Petkov , Thomas Gleixner , linux-edac Subject: [PATCH 4.17 34/70] x86/MCE: Fix stack out-of-bounds write in mce-inject.c: Flags_read() Date: Sun, 24 Jun 2018 23:22:26 +0800 Message-Id: <20180624142742.620481125@linuxfoundation.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180624142740.481662434@linuxfoundation.org> References: <20180624142740.481662434@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tony Luck commit 985c78d3ff8e9c74450fa2bb08eb55e680d999ca upstream. Each of the strings that we want to put into the buf[MAX_FLAG_OPT_SIZE] in flags_read() is two characters long. But the sprintf() adds a trailing newline and will add a terminating NUL byte. So MAX_FLAG_OPT_SIZE needs to be 4. sprintf() calls vsnprintf() and *that* does return: " * The return value is the number of characters which would * be generated for the given input, excluding the trailing * '\0', as per ISO C99." Note the "excluding". Reported-by: Dmitry Vyukov Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Cc: linux-edac Link: http://lkml.kernel.org/r/20180427163707.ktaiysvbk3yhk4wm@agluck-desk Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/mcheck/mce-inject.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/kernel/cpu/mcheck/mce-inject.c +++ b/arch/x86/kernel/cpu/mcheck/mce-inject.c @@ -48,7 +48,7 @@ static struct dentry *dfs_inj; static u8 n_banks; -#define MAX_FLAG_OPT_SIZE 3 +#define MAX_FLAG_OPT_SIZE 4 #define NBCFG 0x44 enum injection_type {