On Wed, May 16, 2018 at 11:37 AM, David Miller <da...@davemloft.net> wrote:
> From: Roopa Prabhu <ro...@cumulusnetworks.com>
> Date: Tue, 15 May 2018 20:55:06 -0700
>
>> +static int inet_rtm_getroute_reply(struct sk_buff *in_skb, struct nlmsghdr
>> *nlh,
>> + __be32 dst, __be32 src, struct flowi4 *fl4,
>> + struct rtable *rt, struct fib_result *res)
>> +{
>> + struct net *net = sock_net(in_skb->sk);
>> + struct rtmsg *rtm = nlmsg_data(nlh);
>> + u32 table_id = RT_TABLE_MAIN;
>> + struct sk_buff *skb;
>> + int err = 0;
>> +
>> + skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
>> + if (!skb)
>> + return -ENOMEM;
>
> If the caller can use GFP_KERNEL, so can this allocation.
yes, but we hold rcu read lock before calling the reply function for fib result.
I did consider allocating the skb before the read lock..but then the
refactoring (into a separate netlink reply func) would seem
unnecessary.
I am fine with pre-allocating and undoing the refactoring if that works better.
