From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:41592 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726130AbgIWIhL (ORCPT ); Wed, 23 Sep 2020 04:37:11 -0400 From: Julian Wiedmann Subject: [PATCH net-next 3/9] s390/qeth: clean up string ops in qeth_l3_parse_ipatoe() Date: Wed, 23 Sep 2020 10:36:54 +0200 Message-Id: <20200923083700.44624-4-jwi@linux.ibm.com> In-Reply-To: <20200923083700.44624-1-jwi@linux.ibm.com> References: <20200923083700.44624-1-jwi@linux.ibm.com> List-ID: To: David Miller , Jakub Kicinski Cc: netdev , linux-s390 , Heiko Carstens , Ursula Braun , Karsten Graul , Julian Wiedmann Indicate the max number of to-be-parsed characters, and avoid copying the address sub-string. Signed-off-by: Julian Wiedmann --- drivers/s390/net/qeth_l3_sys.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) diff --git a/drivers/s390/net/qeth_l3_sys.c b/drivers/s390/net/qeth_l3_sys.c index ca9c95b6bf35..05fa986e30fc 100644 --- a/drivers/s390/net/qeth_l3_sys.c +++ b/drivers/s390/net/qeth_l3_sys.c @@ -409,21 +409,22 @@ static ssize_t qeth_l3_dev_ipato_add4_show(struct device *dev, static int qeth_l3_parse_ipatoe(const char *buf, enum qeth_prot_versions proto, u8 *addr, int *mask_bits) { - const char *start, *end; - char *tmp; - char buffer[40] = {0, }; + const char *start; + char *sep, *tmp; + int rc; - start = buf; - /* get address string */ - end = strchr(start, '/'); - if (!end || (end - start >= 40)) { + /* Expected input pattern: %addr/%mask */ + sep = strnchr(buf, 40, '/'); + if (!sep) return -EINVAL; - } - strncpy(buffer, start, end - start); - if (qeth_l3_string_to_ipaddr(buffer, proto, addr)) { - return -EINVAL; - } - start = end + 1; + + /* Terminate the %addr sub-string, and parse it: */ + *sep = '\0'; + rc = qeth_l3_string_to_ipaddr(buf, proto, addr); + if (rc) + return rc; + + start = sep + 1; *mask_bits = simple_strtoul(start, &tmp, 10); if (!strlen(start) || (tmp == start) || -- 2.17.1