From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-f67.google.com ([209.85.215.67]:44504 "EHLO mail-lf0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932521AbeBVNCY (ORCPT ); Thu, 22 Feb 2018 08:02:24 -0500 Received: by mail-lf0-f67.google.com with SMTP id v9so7268622lfa.11 for ; Thu, 22 Feb 2018 05:02:23 -0800 (PST) From: Serhey Popovych To: netdev@vger.kernel.org Cc: dsahern@gmail.com Subject: [PATCH iproute2-next v3 5/8] veth,vxcan: Save/reinitialize/restore whole @struct ifinfomsg Date: Thu, 22 Feb 2018 15:02:03 +0200 Message-Id: <1519304526-18848-6-git-send-email-serhe.popovych@gmail.com> In-Reply-To: <1519304526-18848-1-git-send-email-serhe.popovych@gmail.com> References: <1519304526-18848-1-git-send-email-serhe.popovych@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: Now in iplink_parse() we use ->ifi_change and ->ifi_flags fields and plan to use ->ifi_index with upcoming change. Saving, restoring and reinitializing individual fields is error prone: using new field in iplink_parse() without updating callers in veth and vxcan will overwrite main device ifinfomsg data. Since @struct ifinfomsg is small enough with known sizeof() compiler may inline memcpy()/memset() with few load/store instructions. Signed-off-by: Serhey Popovych --- ip/iplink_vxcan.c | 22 ++++++++-------------- ip/link_veth.c | 22 ++++++++-------------- 2 files changed, 16 insertions(+), 28 deletions(-) diff --git a/ip/iplink_vxcan.c b/ip/iplink_vxcan.c index ebe9e56..d7e94a0 100644 --- a/ip/iplink_vxcan.c +++ b/ip/iplink_vxcan.c @@ -38,11 +38,10 @@ static int vxcan_parse_opt(struct link_util *lu, int argc, char **argv, char *link = NULL; char *type = NULL; int index = 0; + int group; int err; struct rtattr *data; - int group; - struct ifinfomsg *ifm, *peer_ifm; - unsigned int ifi_flags, ifi_change; + struct ifinfomsg ifm_save, *ifm, *peer_ifm; if (strcmp(argv[0], "peer") != 0) { usage(); @@ -50,10 +49,8 @@ static int vxcan_parse_opt(struct link_util *lu, int argc, char **argv, } ifm = NLMSG_DATA(n); - ifi_flags = ifm->ifi_flags; - ifi_change = ifm->ifi_change; - ifm->ifi_flags = 0; - ifm->ifi_change = 0; + memcpy(&ifm_save, ifm, sizeof(*ifm)); + memset(ifm, 0, sizeof(*ifm)); data = addattr_nest(n, 1024, VXCAN_INFO_PEER); @@ -72,16 +69,13 @@ static int vxcan_parse_opt(struct link_util *lu, int argc, char **argv, IFLA_IFNAME, name, strlen(name) + 1); } - peer_ifm = RTA_DATA(data); - peer_ifm->ifi_index = index; - peer_ifm->ifi_flags = ifm->ifi_flags; - peer_ifm->ifi_change = ifm->ifi_change; - ifm->ifi_flags = ifi_flags; - ifm->ifi_change = ifi_change; - if (group != -1) addattr32(n, 1024, IFLA_GROUP, group); + peer_ifm = RTA_DATA(data); + memcpy(peer_ifm, ifm, sizeof(*ifm)); + memcpy(ifm, &ifm_save, sizeof(*ifm)); + addattr_nest_end(n, data); return argc - 1 - err; } diff --git a/ip/link_veth.c b/ip/link_veth.c index a8e7cf7..b6d37b9 100644 --- a/ip/link_veth.c +++ b/ip/link_veth.c @@ -36,11 +36,10 @@ static int veth_parse_opt(struct link_util *lu, int argc, char **argv, char *link = NULL; char *type = NULL; int index = 0; + int group; int err; struct rtattr *data; - int group; - struct ifinfomsg *ifm, *peer_ifm; - unsigned int ifi_flags, ifi_change; + struct ifinfomsg ifm_save, *ifm, *peer_ifm; if (strcmp(argv[0], "peer") != 0) { usage(); @@ -48,10 +47,8 @@ static int veth_parse_opt(struct link_util *lu, int argc, char **argv, } ifm = NLMSG_DATA(n); - ifi_flags = ifm->ifi_flags; - ifi_change = ifm->ifi_change; - ifm->ifi_flags = 0; - ifm->ifi_change = 0; + memcpy(&ifm_save, ifm, sizeof(*ifm)); + memset(ifm, 0, sizeof(*ifm)); data = addattr_nest(n, 1024, VETH_INFO_PEER); @@ -70,16 +67,13 @@ static int veth_parse_opt(struct link_util *lu, int argc, char **argv, IFLA_IFNAME, name, strlen(name) + 1); } - peer_ifm = RTA_DATA(data); - peer_ifm->ifi_index = index; - peer_ifm->ifi_flags = ifm->ifi_flags; - peer_ifm->ifi_change = ifm->ifi_change; - ifm->ifi_flags = ifi_flags; - ifm->ifi_change = ifi_change; - if (group != -1) addattr32(n, 1024, IFLA_GROUP, group); + peer_ifm = RTA_DATA(data); + memcpy(peer_ifm, ifm, sizeof(*ifm)); + memcpy(ifm, &ifm_save, sizeof(*ifm)); + addattr_nest_end(n, data); return argc - 1 - err; } -- 1.7.10.4