linux-stable/net/ethtool/linkinfo.c
Dan Carpenter 178f67b128 ethtool: linkinfo: remove an unnecessary NULL check
This code generates a Smatch warning:

    net/ethtool/linkinfo.c:143 ethnl_set_linkinfo()
    warn: variable dereferenced before check 'info' (see line 119)

Fortunately, the "info" pointer is never NULL so the check can be
removed.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-05 13:10:02 -07:00

170 lines
5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
#include "netlink.h"
#include "common.h"
struct linkinfo_req_info {
struct ethnl_req_info base;
};
struct linkinfo_reply_data {
struct ethnl_reply_data base;
struct ethtool_link_ksettings ksettings;
struct ethtool_link_settings *lsettings;
};
#define LINKINFO_REPDATA(__reply_base) \
container_of(__reply_base, struct linkinfo_reply_data, base)
static const struct nla_policy
linkinfo_get_policy[ETHTOOL_A_LINKINFO_MAX + 1] = {
[ETHTOOL_A_LINKINFO_UNSPEC] = { .type = NLA_REJECT },
[ETHTOOL_A_LINKINFO_HEADER] = { .type = NLA_NESTED },
[ETHTOOL_A_LINKINFO_PORT] = { .type = NLA_REJECT },
[ETHTOOL_A_LINKINFO_PHYADDR] = { .type = NLA_REJECT },
[ETHTOOL_A_LINKINFO_TP_MDIX] = { .type = NLA_REJECT },
[ETHTOOL_A_LINKINFO_TP_MDIX_CTRL] = { .type = NLA_REJECT },
[ETHTOOL_A_LINKINFO_TRANSCEIVER] = { .type = NLA_REJECT },
};
static int linkinfo_prepare_data(const struct ethnl_req_info *req_base,
struct ethnl_reply_data *reply_base,
struct genl_info *info)
{
struct linkinfo_reply_data *data = LINKINFO_REPDATA(reply_base);
struct net_device *dev = reply_base->dev;
int ret;
data->lsettings = &data->ksettings.base;
ret = ethnl_ops_begin(dev);
if (ret < 0)
return ret;
ret = __ethtool_get_link_ksettings(dev, &data->ksettings);
if (ret < 0 && info)
GENL_SET_ERR_MSG(info, "failed to retrieve link settings");
ethnl_ops_complete(dev);
return ret;
}
static int linkinfo_reply_size(const struct ethnl_req_info *req_base,
const struct ethnl_reply_data *reply_base)
{
return nla_total_size(sizeof(u8)) /* LINKINFO_PORT */
+ nla_total_size(sizeof(u8)) /* LINKINFO_PHYADDR */
+ nla_total_size(sizeof(u8)) /* LINKINFO_TP_MDIX */
+ nla_total_size(sizeof(u8)) /* LINKINFO_TP_MDIX_CTRL */
+ nla_total_size(sizeof(u8)) /* LINKINFO_TRANSCEIVER */
+ 0;
}
static int linkinfo_fill_reply(struct sk_buff *skb,
const struct ethnl_req_info *req_base,
const struct ethnl_reply_data *reply_base)
{
const struct linkinfo_reply_data *data = LINKINFO_REPDATA(reply_base);
if (nla_put_u8(skb, ETHTOOL_A_LINKINFO_PORT, data->lsettings->port) ||
nla_put_u8(skb, ETHTOOL_A_LINKINFO_PHYADDR,
data->lsettings->phy_address) ||
nla_put_u8(skb, ETHTOOL_A_LINKINFO_TP_MDIX,
data->lsettings->eth_tp_mdix) ||
nla_put_u8(skb, ETHTOOL_A_LINKINFO_TP_MDIX_CTRL,
data->lsettings->eth_tp_mdix_ctrl) ||
nla_put_u8(skb, ETHTOOL_A_LINKINFO_TRANSCEIVER,
data->lsettings->transceiver))
return -EMSGSIZE;
return 0;
}
const struct ethnl_request_ops ethnl_linkinfo_request_ops = {
.request_cmd = ETHTOOL_MSG_LINKINFO_GET,
.reply_cmd = ETHTOOL_MSG_LINKINFO_GET_REPLY,
.hdr_attr = ETHTOOL_A_LINKINFO_HEADER,
.max_attr = ETHTOOL_A_LINKINFO_MAX,
.req_info_size = sizeof(struct linkinfo_req_info),
.reply_data_size = sizeof(struct linkinfo_reply_data),
.request_policy = linkinfo_get_policy,
.prepare_data = linkinfo_prepare_data,
.reply_size = linkinfo_reply_size,
.fill_reply = linkinfo_fill_reply,
};
/* LINKINFO_SET */
static const struct nla_policy
linkinfo_set_policy[ETHTOOL_A_LINKINFO_MAX + 1] = {
[ETHTOOL_A_LINKINFO_UNSPEC] = { .type = NLA_REJECT },
[ETHTOOL_A_LINKINFO_HEADER] = { .type = NLA_NESTED },
[ETHTOOL_A_LINKINFO_PORT] = { .type = NLA_U8 },
[ETHTOOL_A_LINKINFO_PHYADDR] = { .type = NLA_U8 },
[ETHTOOL_A_LINKINFO_TP_MDIX] = { .type = NLA_REJECT },
[ETHTOOL_A_LINKINFO_TP_MDIX_CTRL] = { .type = NLA_U8 },
[ETHTOOL_A_LINKINFO_TRANSCEIVER] = { .type = NLA_REJECT },
};
int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr *tb[ETHTOOL_A_LINKINFO_MAX + 1];
struct ethtool_link_ksettings ksettings = {};
struct ethtool_link_settings *lsettings;
struct ethnl_req_info req_info = {};
struct net_device *dev;
bool mod = false;
int ret;
ret = nlmsg_parse(info->nlhdr, GENL_HDRLEN, tb,
ETHTOOL_A_LINKINFO_MAX, linkinfo_set_policy,
info->extack);
if (ret < 0)
return ret;
ret = ethnl_parse_header_dev_get(&req_info,
tb[ETHTOOL_A_LINKINFO_HEADER],
genl_info_net(info), info->extack,
true);
if (ret < 0)
return ret;
dev = req_info.dev;
ret = -EOPNOTSUPP;
if (!dev->ethtool_ops->get_link_ksettings ||
!dev->ethtool_ops->set_link_ksettings)
goto out_dev;
rtnl_lock();
ret = ethnl_ops_begin(dev);
if (ret < 0)
goto out_rtnl;
ret = __ethtool_get_link_ksettings(dev, &ksettings);
if (ret < 0) {
GENL_SET_ERR_MSG(info, "failed to retrieve link settings");
goto out_ops;
}
lsettings = &ksettings.base;
ethnl_update_u8(&lsettings->port, tb[ETHTOOL_A_LINKINFO_PORT], &mod);
ethnl_update_u8(&lsettings->phy_address, tb[ETHTOOL_A_LINKINFO_PHYADDR],
&mod);
ethnl_update_u8(&lsettings->eth_tp_mdix_ctrl,
tb[ETHTOOL_A_LINKINFO_TP_MDIX_CTRL], &mod);
ret = 0;
if (!mod)
goto out_ops;
ret = dev->ethtool_ops->set_link_ksettings(dev, &ksettings);
if (ret < 0)
GENL_SET_ERR_MSG(info, "link settings update failed");
else
ethtool_notify(dev, ETHTOOL_MSG_LINKINFO_NTF, NULL);
out_ops:
ethnl_ops_complete(dev);
out_rtnl:
rtnl_unlock();
out_dev:
dev_put(dev);
return ret;
}