diff options
| author | Jakub Kicinski <jakub.kicinski@netronome.com> | 2018-11-27 22:32:31 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-11-30 13:33:34 -0800 |
| commit | a293974590cfdc2d59c559a54d62a5ecb648104b (patch) | |
| tree | db2bac40463214bd580b4138924f0e082309383c | |
| parent | 420d031822737ef570df6834c0eae26f33988f20 (diff) | |
| download | linux-a293974590cfdc2d59c559a54d62a5ecb648104b.tar.bz2 | |
rtnetlink: avoid frame size warning in rtnl_newlink()
Standard kernel compilation produces the following warning:
net/core/rtnetlink.c: In function ‘rtnl_newlink’:
net/core/rtnetlink.c:3232:1: warning: the frame size of 1288 bytes is larger than 1024 bytes [-Wframe-larger-than=]
}
^
This should not really be an issue, as rtnl_newlink() stack is
generally quite shallow.
Fix the warning by allocating attributes with kmalloc() in a wrapper
and passing it down to rtnl_newlink(), avoiding complexities on error
paths.
Alternatively we could kmalloc() some structure within rtnl_newlink(),
slave attributes look like a good candidate. In practice it adds to
already rather high complexity and length of the function.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/core/rtnetlink.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index ee2caa2fd940..98876cd1e36c 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -2971,14 +2971,13 @@ static int rtnl_group_changelink(const struct sk_buff *skb, return 0; } -static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, - struct netlink_ext_ack *extack) +static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, + struct nlattr **attr, struct netlink_ext_ack *extack) { struct nlattr *slave_attr[RTNL_SLAVE_MAX_TYPE + 1]; unsigned char name_assign_type = NET_NAME_USER; struct nlattr *linkinfo[IFLA_INFO_MAX + 1]; const struct rtnl_link_ops *m_ops = NULL; - struct nlattr *attr[RTNL_MAX_TYPE + 1]; struct net_device *master_dev = NULL; struct net *net = sock_net(skb->sk); const struct rtnl_link_ops *ops; @@ -3226,6 +3225,21 @@ out_unregister: goto out; } +static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack) +{ + struct nlattr **attr; + int ret; + + attr = kmalloc_array(RTNL_MAX_TYPE + 1, sizeof(*attr), GFP_KERNEL); + if (!attr) + return -ENOMEM; + + ret = __rtnl_newlink(skb, nlh, attr, extack); + kfree(attr); + return ret; +} + static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { |