From patchwork Tue Feb 9 15:56:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Fitzgerald X-Patchwork-Id: 12078499 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=-16.8 required=3.0 tests=BAYES_00,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 76CC6C433E0 for ; Tue, 9 Feb 2021 15:57:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E7AF64E9A for ; Tue, 9 Feb 2021 15:57:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232419AbhBIP51 (ORCPT ); Tue, 9 Feb 2021 10:57:27 -0500 Received: from mx0b-001ae601.pphosted.com ([67.231.152.168]:52436 "EHLO mx0b-001ae601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232566AbhBIP50 (ORCPT ); Tue, 9 Feb 2021 10:57:26 -0500 Received: from pps.filterd (m0077474.ppops.net [127.0.0.1]) by mx0b-001ae601.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 119Feba3008252; Tue, 9 Feb 2021 09:56:12 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cirrus.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding : content-type; s=PODMain02222019; bh=5CEkKZOhO+kXh7ZJjl0JUmcEc38rbW3K6ghRgk6Zs3Q=; b=qXUjWgAJECHF3EiAxvEUS/K7dVH7IdUJOlYovbmKqKJ1zZ9ZfPl1K+5wTO3n2RJl5z91 bh3KjNJN6vLDdpBOwqz5qxC//AC5JF7E0ylpGvfKlSIpk2EGYBE/tAq7BvxzPeyJ8h/G 2rZqRQ037e0Fh1svLuYY8hXqUDP3CjtoW0n6JelmP7cjK/1cI17hBzUb2g0c67AkgNeY BucJmA6FtHcEYeCRAjwvu9Vh1z2Wn/1aMZazkBUULXCsN9NS4pFRqXRxdWL7ETUFE7o5 UyEoPLcXN1fEE6cgV3i83acjDVNNdTW772fccI0CL5kW+R5/eFMF45E0Z01PphcrU+66 3g== Received: from ediex01.ad.cirrus.com ([87.246.76.36]) by mx0b-001ae601.pphosted.com with ESMTP id 36hrv2c1af-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Tue, 09 Feb 2021 09:56:12 -0600 Received: from EDIEX01.ad.cirrus.com (198.61.84.80) by EDIEX01.ad.cirrus.com (198.61.84.80) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1913.5; Tue, 9 Feb 2021 15:56:10 +0000 Received: from ediswmail.ad.cirrus.com (198.61.86.93) by EDIEX01.ad.cirrus.com (198.61.84.80) with Microsoft SMTP Server id 15.1.1913.5 via Frontend Transport; Tue, 9 Feb 2021 15:56:10 +0000 Received: from AUSNPC0LSNW1-debian.cirrus.com (AUSNPC0LSNW1.ad.cirrus.com [198.61.64.240]) by ediswmail.ad.cirrus.com (Postfix) with ESMTP id 179F011CA; Tue, 9 Feb 2021 15:56:06 +0000 (UTC) From: Richard Fitzgerald To: , , , , , CC: , , , Richard Fitzgerald Subject: [PATCH v6 1/4] lib: vsprintf: scanf: Negative number must have field width > 1 Date: Tue, 9 Feb 2021 15:56:01 +0000 Message-ID: <20210209155604.6998-1-rf@opensource.cirrus.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxlogscore=522 suspectscore=0 impostorscore=0 clxscore=1015 bulkscore=0 adultscore=0 malwarescore=0 spamscore=0 phishscore=0 priorityscore=1501 mlxscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2102090081 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org If a signed number field starts with a '-' the field width must be > 1, or unlimited, to allow at least one digit after the '-'. This patch adds a check for this. If a signed field starts with '-' and field_width == 1 the scanf will quit. It is ok for a signed number field to have a field width of 1 if it starts with a digit. In that case the single digit can be converted. Signed-off-by: Richard Fitzgerald Reviewed-by: Petr Mladek Acked-by: Andy Shevchenko --- lib/vsprintf.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 3b53c73580c5..28bb26cd1f67 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -3434,8 +3434,12 @@ int vsscanf(const char *buf, const char *fmt, va_list args) str = skip_spaces(str); digit = *str; - if (is_sign && digit == '-') + if (is_sign && digit == '-') { + if (field_width == 1) + break; + digit = *(str + 1); + } if (!digit || (base == 16 && !isxdigit(digit))