5.15-stable review patch. If anyone has any objections, please let me know.
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From: Florent Fourcot florent.fourcot@wifirst.fr
[ 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@mellanox.com Signed-off-by: Florent Fourcot florent.fourcot@wifirst.fr Signed-off-by: Brian Baboch brian.baboch@wifirst.fr Reviewed-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Paolo Abeni pabeni@redhat.com Stable-dep-of: 9415d375d852 ("rtnetlink: Don't ignore IFLA_TARGET_NETNSID when ifname is specified in rtnl_dellink().") Signed-off-by: Sasha Levin sashal@kernel.org --- 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;