tcp/dccp: fix inet_reuseport_add_sock()

David Ahern reported panics in __inet_hash() caused by my recent commit.

The reason is inet_reuseport_add_sock() was still using
sk_nulls_for_each_rcu() instead of sk_for_each_rcu().
SO_REUSEPORT enabled listeners were causing an instant crash.

While chasing this bug, I found that I forgot to clear SOCK_RCU_FREE
flag, as it is inherited from the parent at clone time.

Fixes: 3b24d854cb ("tcp/dccp: do not touch listener sk_refcnt under synflood")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: David Ahern <dsa@cumulusnetworks.com>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2016-04-06 22:07:34 -07:00 committed by David S. Miller
parent 94ab1ea94c
commit 8501786929
2 changed files with 4 additions and 2 deletions

View File

@ -661,6 +661,9 @@ struct sock *inet_csk_clone_lock(const struct sock *sk,
inet_sk(newsk)->inet_sport = htons(inet_rsk(req)->ir_num);
newsk->sk_write_space = sk_stream_write_space;
/* listeners have SOCK_RCU_FREE, not the children */
sock_reset_flag(newsk, SOCK_RCU_FREE);
newsk->sk_mark = inet_rsk(req)->ir_mark;
atomic64_set(&newsk->sk_cookie,
atomic64_read(&inet_rsk(req)->ir_cookie));

View File

@ -439,10 +439,9 @@ static int inet_reuseport_add_sock(struct sock *sk,
bool match_wildcard))
{
struct sock *sk2;
struct hlist_nulls_node *node;
kuid_t uid = sock_i_uid(sk);
sk_nulls_for_each_rcu(sk2, node, &ilb->head) {
sk_for_each_rcu(sk2, &ilb->head) {
if (sk2 != sk &&
sk2->sk_family == sk->sk_family &&
ipv6_only_sock(sk2) == ipv6_only_sock(sk) &&