On Thu, 27 Jul 2017 18:11:32 +0000, Levin, Alexander (Sasha Levin) wrote: > This is useful for directly looking up a task based on class id rather than > having to scan through all open file descriptors. > > Signed-off-by: Sasha Levin <alexander.le...@verizon.com> > --- > > Changes in V2: > - Addressed comments from Cong Wang (use nla_put_u32()) > > include/uapi/linux/inet_diag.h | 1 + > net/ipv4/inet_diag.c | 10 ++++++++++ > 2 files changed, 11 insertions(+) > > diff --git a/include/uapi/linux/inet_diag.h b/include/uapi/linux/inet_diag.h > index bbe201047df6..678496897a68 100644 > --- a/include/uapi/linux/inet_diag.h > +++ b/include/uapi/linux/inet_diag.h > @@ -142,6 +142,7 @@ enum { > INET_DIAG_PAD, > INET_DIAG_MARK, > INET_DIAG_BBRINFO, > + INET_DIAG_CLASS_ID, > __INET_DIAG_MAX, > }; > > diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c > index 3828b3a805cd..2c2445d4bb58 100644 > --- a/net/ipv4/inet_diag.c > +++ b/net/ipv4/inet_diag.c > @@ -274,6 +274,16 @@ int inet_sk_diag_fill(struct sock *sk, struct > inet_connection_sock *icsk, > goto errout; > } > > + if (ext & (1 << (INET_DIAG_CLASS_ID - 1))) { > + u32 classid = 0; > + > +#ifdef CONFIG_SOCK_CGROUP_DATA > + classid = sock_cgroup_classid(&sk->sk_cgrp_data); > +#endif > + > + nla_put_u32(skb, INET_DIAG_CLASS_ID, classid);
You need to check the return value from nla_put_u32() and goto errout if it's set. Perhaps adding __must_check to the nla_put_*() helpers would be a good idea. > + } > + > out: > nlmsg_end(skb, nlh); > return 0;