5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Florent Fourcot <florent.fourcot@xxxxxxxxxx>
[ Upstream commit 5ea08b5286f66ee5ac0150668c92d1718e83e1ad ]
buffer called "ifname" given in function rtnl_dev_get
is always valid when called by setlink/newlink,
but contains only empty string when IFLA_IFNAME is not given. So
IFLA_ALT_IFNAME is always ignored
This patch fixes rtnl_dev_get function with a remove of ifname argument,
and move ifname copy in do_setlink when required.
It extends feature of commit 76c9ac0ee878,
"net: rtnetlink: add possibility to use alternative names as message
handle""
CC: Jiri Pirko <jiri@xxxxxxxxxxxx>
Signed-off-by: Florent Fourcot <florent.fourcot@xxxxxxxxxx>
Signed-off-by: Brian Baboch <brian.baboch@xxxxxxxxxx>
Reviewed-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Stable-dep-of: 9415d375d852 ("rtnetlink: Don't ignore IFLA_TARGET_NETNSID when ifname is specified in rtnl_dellink().")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/core/rtnetlink.c | 69 +++++++++++++++++++-------------------------
1 file changed, 29 insertions(+), 40 deletions(-)
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index d25632fbfa892..4284406740932 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2617,17 +2617,23 @@ static int do_set_proto_down(struct net_device *dev,
static int do_setlink(const struct sk_buff *skb,
struct net_device *dev, struct ifinfomsg *ifm,
struct netlink_ext_ack *extack,
- struct nlattr **tb, char *ifname, int status)
+ struct nlattr **tb, int status)
{
const struct net_device_ops *ops = dev->netdev_ops;
+ char ifname[IFNAMSIZ];
int err;
err = validate_linkmsg(dev, tb, extack);
if (err < 0)
return err;
+ if (tb[IFLA_IFNAME])
+ nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
+ else
+ ifname[0] = '\0';
+
if (tb[IFLA_NET_NS_PID] || tb[IFLA_NET_NS_FD] || tb[IFLA_TARGET_NETNSID]) {
- const char *pat = ifname && ifname[0] ? ifname : NULL;
+ const char *pat = ifname[0] ? ifname : NULL;
struct net *net;
int new_ifindex;
@@ -2974,21 +2980,16 @@ static int do_setlink(const struct sk_buff *skb,
}
static struct net_device *rtnl_dev_get(struct net *net,
- struct nlattr *ifname_attr,
- struct nlattr *altifname_attr,
- char *ifname)
-{
- char buffer[ALTIFNAMSIZ];
-
- if (!ifname) {
- ifname = buffer;
- if (ifname_attr)
- nla_strscpy(ifname, ifname_attr, IFNAMSIZ);
- else if (altifname_attr)
- nla_strscpy(ifname, altifname_attr, ALTIFNAMSIZ);
- else
- return NULL;
- }
+ struct nlattr *tb[])
+{
+ char ifname[ALTIFNAMSIZ];
+
+ if (tb[IFLA_IFNAME])
+ nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
+ else if (tb[IFLA_ALT_IFNAME])
+ nla_strscpy(ifname, tb[IFLA_ALT_IFNAME], ALTIFNAMSIZ);
+ else
+ return NULL;
return __dev_get_by_name(net, ifname);
}
@@ -3001,7 +3002,6 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
struct net_device *dev;
int err;
struct nlattr *tb[IFLA_MAX+1];
- char ifname[IFNAMSIZ];
err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFLA_MAX,
ifla_policy, extack);
@@ -3012,17 +3012,12 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
if (err < 0)
goto errout;
- if (tb[IFLA_IFNAME])
- nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
- else
- ifname[0] = '\0';
-
err = -EINVAL;
ifm = nlmsg_data(nlh);
if (ifm->ifi_index > 0)
dev = __dev_get_by_index(net, ifm->ifi_index);
else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
- dev = rtnl_dev_get(net, NULL, tb[IFLA_ALT_IFNAME], ifname);
+ dev = rtnl_dev_get(net, tb);
else
goto errout;
@@ -3031,7 +3026,7 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
goto errout;
}
- err = do_setlink(skb, dev, ifm, extack, tb, ifname, 0);
+ err = do_setlink(skb, dev, ifm, extack, tb, 0);
errout:
return err;
}
@@ -3120,8 +3115,7 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh,
if (ifm->ifi_index > 0)
dev = __dev_get_by_index(tgt_net, ifm->ifi_index);
else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
- dev = rtnl_dev_get(net, tb[IFLA_IFNAME],
- tb[IFLA_ALT_IFNAME], NULL);
+ dev = rtnl_dev_get(net, tb);
else if (tb[IFLA_GROUP])
err = rtnl_group_dellink(tgt_net, nla_get_u32(tb[IFLA_GROUP]));
else
@@ -3267,7 +3261,7 @@ static int rtnl_group_changelink(const struct sk_buff *skb,
for_each_netdev_safe(net, dev, aux) {
if (dev->group == group) {
- err = do_setlink(skb, dev, ifm, extack, tb, NULL, 0);
+ err = do_setlink(skb, dev, ifm, extack, tb, 0);
if (err < 0)
return err;
}
@@ -3309,11 +3303,6 @@ static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
if (err < 0)
return err;
- if (tb[IFLA_IFNAME])
- nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
- else
- ifname[0] = '\0';
-
ifm = nlmsg_data(nlh);
if (ifm->ifi_index > 0) {
link_specified = true;
@@ -3323,7 +3312,7 @@ static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
return -EINVAL;
} else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME]) {
link_specified = true;
- dev = rtnl_dev_get(net, NULL, tb[IFLA_ALT_IFNAME], ifname);
+ dev = rtnl_dev_get(net, tb);
} else {
link_specified = false;
dev = NULL;
@@ -3426,7 +3415,7 @@ static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
status |= DO_SETLINK_NOTIFY;
}
- return do_setlink(skb, dev, ifm, extack, tb, ifname, status);
+ return do_setlink(skb, dev, ifm, extack, tb, status);
}
if (!(nlh->nlmsg_flags & NLM_F_CREATE)) {
@@ -3463,7 +3452,9 @@ static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
if (!ops->alloc && !ops->setup)
return -EOPNOTSUPP;
- if (!ifname[0]) {
+ if (tb[IFLA_IFNAME]) {
+ nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
+ } else {
snprintf(ifname, IFNAMSIZ, "%s%%d", ops->kind);
name_assign_type = NET_NAME_ENUM;
}
@@ -3635,8 +3626,7 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr *nlh,
if (ifm->ifi_index > 0)
dev = __dev_get_by_index(tgt_net, ifm->ifi_index);
else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
- dev = rtnl_dev_get(tgt_net, tb[IFLA_IFNAME],
- tb[IFLA_ALT_IFNAME], NULL);
+ dev = rtnl_dev_get(tgt_net, tb);
else
goto out;
@@ -3731,8 +3721,7 @@ static int rtnl_linkprop(int cmd, struct sk_buff *skb, struct nlmsghdr *nlh,
if (ifm->ifi_index > 0)
dev = __dev_get_by_index(net, ifm->ifi_index);
else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
- dev = rtnl_dev_get(net, tb[IFLA_IFNAME],
- tb[IFLA_ALT_IFNAME], NULL);
+ dev = rtnl_dev_get(net, tb);
else
return -EINVAL;
--
2.43.0
