linux/net/netlink/diag.c
Andrey Vagin 733ade23de netlink: don't forget to release a rhashtable_iter structure
This bug was detected by kmemleak:
unreferenced object 0xffff8804269cc3c0 (size 64):
  comm "criu", pid 1042, jiffies 4294907360 (age 13.713s)
  hex dump (first 32 bytes):
    a0 32 cc 2c 04 88 ff ff 00 00 00 00 00 00 00 00  .2.,............
    00 01 00 00 00 00 ad de 00 02 00 00 00 00 ad de  ................
  backtrace:
    [<ffffffff8184dffa>] kmemleak_alloc+0x4a/0xa0
    [<ffffffff8124720f>] kmem_cache_alloc_trace+0x10f/0x280
    [<ffffffffa02864cc>] __netlink_diag_dump+0x26c/0x290 [netlink_diag]

v2: don't remove a reference on a rhashtable_iter structure to
    release it from netlink_diag_dump_done

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Fixes: ad20207432 ("netlink: Use rhashtable walk interface in diag dump")
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-07 17:29:38 -07:00

242 lines
4.8 KiB
C

#include <linux/module.h>
#include <net/sock.h>
#include <linux/netlink.h>
#include <linux/sock_diag.h>
#include <linux/netlink_diag.h>
#include <linux/rhashtable.h>
#include "af_netlink.h"
static int sk_diag_dump_groups(struct sock *sk, struct sk_buff *nlskb)
{
struct netlink_sock *nlk = nlk_sk(sk);
if (nlk->groups == NULL)
return 0;
return nla_put(nlskb, NETLINK_DIAG_GROUPS, NLGRPSZ(nlk->ngroups),
nlk->groups);
}
static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
struct netlink_diag_req *req,
u32 portid, u32 seq, u32 flags, int sk_ino)
{
struct nlmsghdr *nlh;
struct netlink_diag_msg *rep;
struct netlink_sock *nlk = nlk_sk(sk);
nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep),
flags);
if (!nlh)
return -EMSGSIZE;
rep = nlmsg_data(nlh);
rep->ndiag_family = AF_NETLINK;
rep->ndiag_type = sk->sk_type;
rep->ndiag_protocol = sk->sk_protocol;
rep->ndiag_state = sk->sk_state;
rep->ndiag_ino = sk_ino;
rep->ndiag_portid = nlk->portid;
rep->ndiag_dst_portid = nlk->dst_portid;
rep->ndiag_dst_group = nlk->dst_group;
sock_diag_save_cookie(sk, rep->ndiag_cookie);
if ((req->ndiag_show & NDIAG_SHOW_GROUPS) &&
sk_diag_dump_groups(sk, skb))
goto out_nlmsg_trim;
if ((req->ndiag_show & NDIAG_SHOW_MEMINFO) &&
sock_diag_put_meminfo(sk, skb, NETLINK_DIAG_MEMINFO))
goto out_nlmsg_trim;
nlmsg_end(skb, nlh);
return 0;
out_nlmsg_trim:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
int protocol, int s_num)
{
struct rhashtable_iter *hti = (void *)cb->args[2];
struct netlink_table *tbl = &nl_table[protocol];
struct net *net = sock_net(skb->sk);
struct netlink_diag_req *req;
struct netlink_sock *nlsk;
struct sock *sk;
int num = 2;
int ret = 0;
req = nlmsg_data(cb->nlh);
if (s_num > 1)
goto mc_list;
num--;
if (!hti) {
hti = kmalloc(sizeof(*hti), GFP_KERNEL);
if (!hti)
return -ENOMEM;
cb->args[2] = (long)hti;
}
if (!s_num)
rhashtable_walk_enter(&tbl->hash, hti);
ret = rhashtable_walk_start(hti);
if (ret == -EAGAIN)
ret = 0;
if (ret)
goto stop;
while ((nlsk = rhashtable_walk_next(hti))) {
if (IS_ERR(nlsk)) {
ret = PTR_ERR(nlsk);
if (ret == -EAGAIN) {
ret = 0;
continue;
}
break;
}
sk = (struct sock *)nlsk;
if (!net_eq(sock_net(sk), net))
continue;
if (sk_diag_fill(sk, skb, req,
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
NLM_F_MULTI,
sock_i_ino(sk)) < 0) {
ret = 1;
break;
}
}
stop:
rhashtable_walk_stop(hti);
if (ret)
goto done;
rhashtable_walk_exit(hti);
num++;
mc_list:
read_lock(&nl_table_lock);
sk_for_each_bound(sk, &tbl->mc_list) {
if (sk_hashed(sk))
continue;
if (!net_eq(sock_net(sk), net))
continue;
if (num < s_num) {
num++;
continue;
}
if (sk_diag_fill(sk, skb, req,
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
NLM_F_MULTI,
sock_i_ino(sk)) < 0) {
ret = 1;
break;
}
num++;
}
read_unlock(&nl_table_lock);
done:
cb->args[0] = num;
return ret;
}
static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
struct netlink_diag_req *req;
int s_num = cb->args[0];
int err = 0;
req = nlmsg_data(cb->nlh);
if (req->sdiag_protocol == NDIAG_PROTO_ALL) {
int i;
for (i = cb->args[1]; i < MAX_LINKS; i++) {
err = __netlink_diag_dump(skb, cb, i, s_num);
if (err)
break;
s_num = 0;
}
cb->args[1] = i;
} else {
if (req->sdiag_protocol >= MAX_LINKS) {
read_unlock(&nl_table_lock);
rcu_read_unlock();
return -ENOENT;
}
err = __netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num);
}
return err < 0 ? err : skb->len;
}
static int netlink_diag_dump_done(struct netlink_callback *cb)
{
struct rhashtable_iter *hti = (void *)cb->args[2];
if (cb->args[0] == 1)
rhashtable_walk_exit(hti);
kfree(hti);
return 0;
}
static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
{
int hdrlen = sizeof(struct netlink_diag_req);
struct net *net = sock_net(skb->sk);
if (nlmsg_len(h) < hdrlen)
return -EINVAL;
if (h->nlmsg_flags & NLM_F_DUMP) {
struct netlink_dump_control c = {
.dump = netlink_diag_dump,
.done = netlink_diag_dump_done,
};
return netlink_dump_start(net->diag_nlsk, skb, h, &c);
} else
return -EOPNOTSUPP;
}
static const struct sock_diag_handler netlink_diag_handler = {
.family = AF_NETLINK,
.dump = netlink_diag_handler_dump,
};
static int __init netlink_diag_init(void)
{
return sock_diag_register(&netlink_diag_handler);
}
static void __exit netlink_diag_exit(void)
{
sock_diag_unregister(&netlink_diag_handler);
}
module_init(netlink_diag_init);
module_exit(netlink_diag_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 16 /* AF_NETLINK */);