linux-stable/net/ipv4/inet_diag.c
Xin Long bf2ae2e4bf sock_diag: request _diag module only when the family or proto has been registered
Now when using 'ss' in iproute, kernel would try to load all _diag
modules, which also causes corresponding family and proto modules
to be loaded as well due to module dependencies.

Like after running 'ss', sctp, dccp, af_packet (if it works as a module)
would be loaded.

For example:

  $ lsmod|grep sctp
  $ ss
  $ lsmod|grep sctp
  sctp_diag              16384  0
  sctp                  323584  5 sctp_diag
  inet_diag              24576  4 raw_diag,tcp_diag,sctp_diag,udp_diag
  libcrc32c              16384  3 nf_conntrack,nf_nat,sctp

As these family and proto modules are loaded unintentionally, it
could cause some problems, like:

- Some debug tools use 'ss' to collect the socket info, which loads all
  those diag and family and protocol modules. It's noisy for identifying
  issues.

- Users usually expect to drop sctp init packet silently when they
  have no sense of sctp protocol instead of sending abort back.

- It wastes resources (especially with multiple netns), and SCTP module
  can't be unloaded once it's loaded.

...

In short, it's really inappropriate to have these family and proto
modules loaded unexpectedly when just doing debugging with inet_diag.

This patch is to introduce sock_load_diag_module() where it loads
the _diag module only when it's corresponding family or proto has
been already registered.

Note that we can't just load _diag module without the family or
proto loaded, as some symbols used in _diag module are from the
family or proto module.

v1->v2:
  - move inet proto check to inet_diag to avoid a compiling err.
v2->v3:
  - define sock_load_diag_module in sock.c and export one symbol
    only.
  - improve the changelog.

Reported-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Phil Sutter <phil@nwl.cc>
Acked-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-12 11:03:42 -04:00

1313 lines
31 KiB
C

/*
* inet_diag.c Module for monitoring INET transport protocols sockets.
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <linux/cache.h>
#include <linux/init.h>
#include <linux/time.h>
#include <net/icmp.h>
#include <net/tcp.h>
#include <net/ipv6.h>
#include <net/inet_common.h>
#include <net/inet_connection_sock.h>
#include <net/inet_hashtables.h>
#include <net/inet_timewait_sock.h>
#include <net/inet6_hashtables.h>
#include <net/netlink.h>
#include <linux/inet.h>
#include <linux/stddef.h>
#include <linux/inet_diag.h>
#include <linux/sock_diag.h>
static const struct inet_diag_handler **inet_diag_table;
struct inet_diag_entry {
const __be32 *saddr;
const __be32 *daddr;
u16 sport;
u16 dport;
u16 family;
u16 userlocks;
u32 ifindex;
u32 mark;
};
static DEFINE_MUTEX(inet_diag_table_mutex);
static const struct inet_diag_handler *inet_diag_lock_handler(int proto)
{
if (!inet_diag_table[proto])
sock_load_diag_module(AF_INET, proto);
mutex_lock(&inet_diag_table_mutex);
if (!inet_diag_table[proto])
return ERR_PTR(-ENOENT);
return inet_diag_table[proto];
}
static void inet_diag_unlock_handler(const struct inet_diag_handler *handler)
{
mutex_unlock(&inet_diag_table_mutex);
}
void inet_diag_msg_common_fill(struct inet_diag_msg *r, struct sock *sk)
{
r->idiag_family = sk->sk_family;
r->id.idiag_sport = htons(sk->sk_num);
r->id.idiag_dport = sk->sk_dport;
r->id.idiag_if = sk->sk_bound_dev_if;
sock_diag_save_cookie(sk, r->id.idiag_cookie);
#if IS_ENABLED(CONFIG_IPV6)
if (sk->sk_family == AF_INET6) {
*(struct in6_addr *)r->id.idiag_src = sk->sk_v6_rcv_saddr;
*(struct in6_addr *)r->id.idiag_dst = sk->sk_v6_daddr;
} else
#endif
{
memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src));
memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst));
r->id.idiag_src[0] = sk->sk_rcv_saddr;
r->id.idiag_dst[0] = sk->sk_daddr;
}
}
EXPORT_SYMBOL_GPL(inet_diag_msg_common_fill);
static size_t inet_sk_attr_size(struct sock *sk,
const struct inet_diag_req_v2 *req,
bool net_admin)
{
const struct inet_diag_handler *handler;
size_t aux = 0;
handler = inet_diag_table[req->sdiag_protocol];
if (handler && handler->idiag_get_aux_size)
aux = handler->idiag_get_aux_size(sk, net_admin);
return nla_total_size(sizeof(struct tcp_info))
+ nla_total_size(1) /* INET_DIAG_SHUTDOWN */
+ nla_total_size(1) /* INET_DIAG_TOS */
+ nla_total_size(1) /* INET_DIAG_TCLASS */
+ nla_total_size(4) /* INET_DIAG_MARK */
+ nla_total_size(sizeof(struct inet_diag_meminfo))
+ nla_total_size(sizeof(struct inet_diag_msg))
+ nla_total_size(SK_MEMINFO_VARS * sizeof(u32))
+ nla_total_size(TCP_CA_NAME_MAX)
+ nla_total_size(sizeof(struct tcpvegas_info))
+ aux
+ 64;
}
int inet_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb,
struct inet_diag_msg *r, int ext,
struct user_namespace *user_ns,
bool net_admin)
{
const struct inet_sock *inet = inet_sk(sk);
if (nla_put_u8(skb, INET_DIAG_SHUTDOWN, sk->sk_shutdown))
goto errout;
/* IPv6 dual-stack sockets use inet->tos for IPv4 connections,
* hence this needs to be included regardless of socket family.
*/
if (ext & (1 << (INET_DIAG_TOS - 1)))
if (nla_put_u8(skb, INET_DIAG_TOS, inet->tos) < 0)
goto errout;
#if IS_ENABLED(CONFIG_IPV6)
if (r->idiag_family == AF_INET6) {
if (ext & (1 << (INET_DIAG_TCLASS - 1)))
if (nla_put_u8(skb, INET_DIAG_TCLASS,
inet6_sk(sk)->tclass) < 0)
goto errout;
if (((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
nla_put_u8(skb, INET_DIAG_SKV6ONLY, ipv6_only_sock(sk)))
goto errout;
}
#endif
if (net_admin && nla_put_u32(skb, INET_DIAG_MARK, sk->sk_mark))
goto errout;
r->idiag_uid = from_kuid_munged(user_ns, sock_i_uid(sk));
r->idiag_inode = sock_i_ino(sk);
return 0;
errout:
return 1;
}
EXPORT_SYMBOL_GPL(inet_diag_msg_attrs_fill);
int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
struct sk_buff *skb, const struct inet_diag_req_v2 *req,
struct user_namespace *user_ns,
u32 portid, u32 seq, u16 nlmsg_flags,
const struct nlmsghdr *unlh,
bool net_admin)
{
const struct tcp_congestion_ops *ca_ops;
const struct inet_diag_handler *handler;
int ext = req->idiag_ext;
struct inet_diag_msg *r;
struct nlmsghdr *nlh;
struct nlattr *attr;
void *info = NULL;
handler = inet_diag_table[req->sdiag_protocol];
BUG_ON(!handler);
nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
nlmsg_flags);
if (!nlh)
return -EMSGSIZE;
r = nlmsg_data(nlh);
BUG_ON(!sk_fullsock(sk));
inet_diag_msg_common_fill(r, sk);
r->idiag_state = sk->sk_state;
r->idiag_timer = 0;
r->idiag_retrans = 0;
if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns, net_admin))
goto errout;
if (ext & (1 << (INET_DIAG_MEMINFO - 1))) {
struct inet_diag_meminfo minfo = {
.idiag_rmem = sk_rmem_alloc_get(sk),
.idiag_wmem = sk->sk_wmem_queued,
.idiag_fmem = sk->sk_forward_alloc,
.idiag_tmem = sk_wmem_alloc_get(sk),
};
if (nla_put(skb, INET_DIAG_MEMINFO, sizeof(minfo), &minfo) < 0)
goto errout;
}
if (ext & (1 << (INET_DIAG_SKMEMINFO - 1)))
if (sock_diag_put_meminfo(sk, skb, INET_DIAG_SKMEMINFO))
goto errout;
/*
* RAW sockets might have user-defined protocols assigned,
* so report the one supplied on socket creation.
*/
if (sk->sk_type == SOCK_RAW) {
if (nla_put_u8(skb, INET_DIAG_PROTOCOL, sk->sk_protocol))
goto errout;
}
if (!icsk) {
handler->idiag_get_info(sk, r, NULL);
goto out;
}
if (icsk->icsk_pending == ICSK_TIME_RETRANS ||
icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT ||
icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) {
r->idiag_timer = 1;
r->idiag_retrans = icsk->icsk_retransmits;
r->idiag_expires =
jiffies_to_msecs(icsk->icsk_timeout - jiffies);
} else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
r->idiag_timer = 4;
r->idiag_retrans = icsk->icsk_probes_out;
r->idiag_expires =
jiffies_to_msecs(icsk->icsk_timeout - jiffies);
} else if (timer_pending(&sk->sk_timer)) {
r->idiag_timer = 2;
r->idiag_retrans = icsk->icsk_probes_out;
r->idiag_expires =
jiffies_to_msecs(sk->sk_timer.expires - jiffies);
} else {
r->idiag_timer = 0;
r->idiag_expires = 0;
}
if ((ext & (1 << (INET_DIAG_INFO - 1))) && handler->idiag_info_size) {
attr = nla_reserve_64bit(skb, INET_DIAG_INFO,
handler->idiag_info_size,
INET_DIAG_PAD);
if (!attr)
goto errout;
info = nla_data(attr);
}
if (ext & (1 << (INET_DIAG_CONG - 1))) {
int err = 0;
rcu_read_lock();
ca_ops = READ_ONCE(icsk->icsk_ca_ops);
if (ca_ops)
err = nla_put_string(skb, INET_DIAG_CONG, ca_ops->name);
rcu_read_unlock();
if (err < 0)
goto errout;
}
handler->idiag_get_info(sk, r, info);
if (ext & (1 << (INET_DIAG_INFO - 1)) && handler->idiag_get_aux)
if (handler->idiag_get_aux(sk, net_admin, skb) < 0)
goto errout;
if (sk->sk_state < TCP_TIME_WAIT) {
union tcp_cc_info info;
size_t sz = 0;
int attr;
rcu_read_lock();
ca_ops = READ_ONCE(icsk->icsk_ca_ops);
if (ca_ops && ca_ops->get_info)
sz = ca_ops->get_info(sk, ext, &attr, &info);
rcu_read_unlock();
if (sz && nla_put(skb, attr, sz, &info) < 0)
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
if (nla_put_u32(skb, INET_DIAG_CLASS_ID, classid))
goto errout;
}
out:
nlmsg_end(skb, nlh);
return 0;
errout:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
EXPORT_SYMBOL_GPL(inet_sk_diag_fill);
static int inet_csk_diag_fill(struct sock *sk,
struct sk_buff *skb,
const struct inet_diag_req_v2 *req,
struct user_namespace *user_ns,
u32 portid, u32 seq, u16 nlmsg_flags,
const struct nlmsghdr *unlh,
bool net_admin)
{
return inet_sk_diag_fill(sk, inet_csk(sk), skb, req, user_ns,
portid, seq, nlmsg_flags, unlh, net_admin);
}
static int inet_twsk_diag_fill(struct sock *sk,
struct sk_buff *skb,
u32 portid, u32 seq, u16 nlmsg_flags,
const struct nlmsghdr *unlh)
{
struct inet_timewait_sock *tw = inet_twsk(sk);
struct inet_diag_msg *r;
struct nlmsghdr *nlh;
long tmo;
nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
nlmsg_flags);
if (!nlh)
return -EMSGSIZE;
r = nlmsg_data(nlh);
BUG_ON(tw->tw_state != TCP_TIME_WAIT);
tmo = tw->tw_timer.expires - jiffies;
if (tmo < 0)
tmo = 0;
inet_diag_msg_common_fill(r, sk);
r->idiag_retrans = 0;
r->idiag_state = tw->tw_substate;
r->idiag_timer = 3;
r->idiag_expires = jiffies_to_msecs(tmo);
r->idiag_rqueue = 0;
r->idiag_wqueue = 0;
r->idiag_uid = 0;
r->idiag_inode = 0;
nlmsg_end(skb, nlh);
return 0;
}
static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb,
u32 portid, u32 seq, u16 nlmsg_flags,
const struct nlmsghdr *unlh, bool net_admin)
{
struct request_sock *reqsk = inet_reqsk(sk);
struct inet_diag_msg *r;
struct nlmsghdr *nlh;
long tmo;
nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r),
nlmsg_flags);
if (!nlh)
return -EMSGSIZE;
r = nlmsg_data(nlh);
inet_diag_msg_common_fill(r, sk);
r->idiag_state = TCP_SYN_RECV;
r->idiag_timer = 1;
r->idiag_retrans = reqsk->num_retrans;
BUILD_BUG_ON(offsetof(struct inet_request_sock, ir_cookie) !=
offsetof(struct sock, sk_cookie));
tmo = inet_reqsk(sk)->rsk_timer.expires - jiffies;
r->idiag_expires = (tmo >= 0) ? jiffies_to_msecs(tmo) : 0;
r->idiag_rqueue = 0;
r->idiag_wqueue = 0;
r->idiag_uid = 0;
r->idiag_inode = 0;
if (net_admin && nla_put_u32(skb, INET_DIAG_MARK,
inet_rsk(reqsk)->ir_mark))
return -EMSGSIZE;
nlmsg_end(skb, nlh);
return 0;
}
static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
const struct inet_diag_req_v2 *r,
struct user_namespace *user_ns,
u32 portid, u32 seq, u16 nlmsg_flags,
const struct nlmsghdr *unlh, bool net_admin)
{
if (sk->sk_state == TCP_TIME_WAIT)
return inet_twsk_diag_fill(sk, skb, portid, seq,
nlmsg_flags, unlh);
if (sk->sk_state == TCP_NEW_SYN_RECV)
return inet_req_diag_fill(sk, skb, portid, seq,
nlmsg_flags, unlh, net_admin);
return inet_csk_diag_fill(sk, skb, r, user_ns, portid, seq,
nlmsg_flags, unlh, net_admin);
}
struct sock *inet_diag_find_one_icsk(struct net *net,
struct inet_hashinfo *hashinfo,
const struct inet_diag_req_v2 *req)
{
struct sock *sk;
rcu_read_lock();
if (req->sdiag_family == AF_INET)
sk = inet_lookup(net, hashinfo, NULL, 0, req->id.idiag_dst[0],
req->id.idiag_dport, req->id.idiag_src[0],
req->id.idiag_sport, req->id.idiag_if);
#if IS_ENABLED(CONFIG_IPV6)
else if (req->sdiag_family == AF_INET6) {
if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
sk = inet_lookup(net, hashinfo, NULL, 0, req->id.idiag_dst[3],
req->id.idiag_dport, req->id.idiag_src[3],
req->id.idiag_sport, req->id.idiag_if);
else
sk = inet6_lookup(net, hashinfo, NULL, 0,
(struct in6_addr *)req->id.idiag_dst,
req->id.idiag_dport,
(struct in6_addr *)req->id.idiag_src,
req->id.idiag_sport,
req->id.idiag_if);
}
#endif
else {
rcu_read_unlock();
return ERR_PTR(-EINVAL);
}
rcu_read_unlock();
if (!sk)
return ERR_PTR(-ENOENT);
if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) {
sock_gen_put(sk);
return ERR_PTR(-ENOENT);
}
return sk;
}
EXPORT_SYMBOL_GPL(inet_diag_find_one_icsk);
int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,
struct sk_buff *in_skb,
const struct nlmsghdr *nlh,
const struct inet_diag_req_v2 *req)
{
bool net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN);
struct net *net = sock_net(in_skb->sk);
struct sk_buff *rep;
struct sock *sk;
int err;
sk = inet_diag_find_one_icsk(net, hashinfo, req);
if (IS_ERR(sk))
return PTR_ERR(sk);
rep = nlmsg_new(inet_sk_attr_size(sk, req, net_admin), GFP_KERNEL);
if (!rep) {
err = -ENOMEM;
goto out;
}
err = sk_diag_fill(sk, rep, req,
sk_user_ns(NETLINK_CB(in_skb).sk),
NETLINK_CB(in_skb).portid,
nlh->nlmsg_seq, 0, nlh, net_admin);
if (err < 0) {
WARN_ON(err == -EMSGSIZE);
nlmsg_free(rep);
goto out;
}
err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
MSG_DONTWAIT);
if (err > 0)
err = 0;
out:
if (sk)
sock_gen_put(sk);
return err;
}
EXPORT_SYMBOL_GPL(inet_diag_dump_one_icsk);
static int inet_diag_cmd_exact(int cmd, struct sk_buff *in_skb,
const struct nlmsghdr *nlh,
const struct inet_diag_req_v2 *req)
{
const struct inet_diag_handler *handler;
int err;
handler = inet_diag_lock_handler(req->sdiag_protocol);
if (IS_ERR(handler))
err = PTR_ERR(handler);
else if (cmd == SOCK_DIAG_BY_FAMILY)
err = handler->dump_one(in_skb, nlh, req);
else if (cmd == SOCK_DESTROY && handler->destroy)
err = handler->destroy(in_skb, req);
else
err = -EOPNOTSUPP;
inet_diag_unlock_handler(handler);
return err;
}
static int bitstring_match(const __be32 *a1, const __be32 *a2, int bits)
{
int words = bits >> 5;
bits &= 0x1f;
if (words) {
if (memcmp(a1, a2, words << 2))
return 0;
}
if (bits) {
__be32 w1, w2;
__be32 mask;
w1 = a1[words];
w2 = a2[words];
mask = htonl((0xffffffff) << (32 - bits));
if ((w1 ^ w2) & mask)
return 0;
}
return 1;
}
static int inet_diag_bc_run(const struct nlattr *_bc,
const struct inet_diag_entry *entry)
{
const void *bc = nla_data(_bc);
int len = nla_len(_bc);
while (len > 0) {
int yes = 1;
const struct inet_diag_bc_op *op = bc;
switch (op->code) {
case INET_DIAG_BC_NOP:
break;
case INET_DIAG_BC_JMP:
yes = 0;
break;
case INET_DIAG_BC_S_EQ:
yes = entry->sport == op[1].no;
break;
case INET_DIAG_BC_S_GE:
yes = entry->sport >= op[1].no;
break;
case INET_DIAG_BC_S_LE:
yes = entry->sport <= op[1].no;
break;
case INET_DIAG_BC_D_EQ:
yes = entry->dport == op[1].no;
break;
case INET_DIAG_BC_D_GE:
yes = entry->dport >= op[1].no;
break;
case INET_DIAG_BC_D_LE:
yes = entry->dport <= op[1].no;
break;
case INET_DIAG_BC_AUTO:
yes = !(entry->userlocks & SOCK_BINDPORT_LOCK);
break;
case INET_DIAG_BC_S_COND:
case INET_DIAG_BC_D_COND: {
const struct inet_diag_hostcond *cond;
const __be32 *addr;
cond = (const struct inet_diag_hostcond *)(op + 1);
if (cond->port != -1 &&
cond->port != (op->code == INET_DIAG_BC_S_COND ?
entry->sport : entry->dport)) {
yes = 0;
break;
}
if (op->code == INET_DIAG_BC_S_COND)
addr = entry->saddr;
else
addr = entry->daddr;
if (cond->family != AF_UNSPEC &&
cond->family != entry->family) {
if (entry->family == AF_INET6 &&
cond->family == AF_INET) {
if (addr[0] == 0 && addr[1] == 0 &&
addr[2] == htonl(0xffff) &&
bitstring_match(addr + 3,
cond->addr,
cond->prefix_len))
break;
}
yes = 0;
break;
}
if (cond->prefix_len == 0)
break;
if (bitstring_match(addr, cond->addr,
cond->prefix_len))
break;
yes = 0;
break;
}
case INET_DIAG_BC_DEV_COND: {
u32 ifindex;
ifindex = *((const u32 *)(op + 1));
if (ifindex != entry->ifindex)
yes = 0;
break;
}
case INET_DIAG_BC_MARK_COND: {
struct inet_diag_markcond *cond;
cond = (struct inet_diag_markcond *)(op + 1);
if ((entry->mark & cond->mask) != cond->mark)
yes = 0;
break;
}
}
if (yes) {
len -= op->yes;
bc += op->yes;
} else {
len -= op->no;
bc += op->no;
}
}
return len == 0;
}
/* This helper is available for all sockets (ESTABLISH, TIMEWAIT, SYN_RECV)
*/
static void entry_fill_addrs(struct inet_diag_entry *entry,
const struct sock *sk)
{
#if IS_ENABLED(CONFIG_IPV6)
if (sk->sk_family == AF_INET6) {
entry->saddr = sk->sk_v6_rcv_saddr.s6_addr32;
entry->daddr = sk->sk_v6_daddr.s6_addr32;
} else
#endif
{
entry->saddr = &sk->sk_rcv_saddr;
entry->daddr = &sk->sk_daddr;
}
}
int inet_diag_bc_sk(const struct nlattr *bc, struct sock *sk)
{
struct inet_sock *inet = inet_sk(sk);
struct inet_diag_entry entry;
if (!bc)
return 1;
entry.family = sk->sk_family;
entry_fill_addrs(&entry, sk);
entry.sport = inet->inet_num;
entry.dport = ntohs(inet->inet_dport);
entry.ifindex = sk->sk_bound_dev_if;
entry.userlocks = sk_fullsock(sk) ? sk->sk_userlocks : 0;
if (sk_fullsock(sk))
entry.mark = sk->sk_mark;
else if (sk->sk_state == TCP_NEW_SYN_RECV)
entry.mark = inet_rsk(inet_reqsk(sk))->ir_mark;
else
entry.mark = 0;
return inet_diag_bc_run(bc, &entry);
}
EXPORT_SYMBOL_GPL(inet_diag_bc_sk);
static int valid_cc(const void *bc, int len, int cc)
{
while (len >= 0) {
const struct inet_diag_bc_op *op = bc;
if (cc > len)
return 0;
if (cc == len)
return 1;
if (op->yes < 4 || op->yes & 3)
return 0;
len -= op->yes;
bc += op->yes;
}
return 0;
}
/* data is u32 ifindex */
static bool valid_devcond(const struct inet_diag_bc_op *op, int len,
int *min_len)
{
/* Check ifindex space. */
*min_len += sizeof(u32);
if (len < *min_len)
return false;
return true;
}
/* Validate an inet_diag_hostcond. */
static bool valid_hostcond(const struct inet_diag_bc_op *op, int len,
int *min_len)
{
struct inet_diag_hostcond *cond;
int addr_len;
/* Check hostcond space. */
*min_len += sizeof(struct inet_diag_hostcond);
if (len < *min_len)
return false;
cond = (struct inet_diag_hostcond *)(op + 1);
/* Check address family and address length. */
switch (cond->family) {
case AF_UNSPEC:
addr_len = 0;
break;
case AF_INET:
addr_len = sizeof(struct in_addr);
break;
case AF_INET6:
addr_len = sizeof(struct in6_addr);
break;
default:
return false;
}
*min_len += addr_len;
if (len < *min_len)
return false;
/* Check prefix length (in bits) vs address length (in bytes). */
if (cond->prefix_len > 8 * addr_len)
return false;
return true;
}
/* Validate a port comparison operator. */
static bool valid_port_comparison(const struct inet_diag_bc_op *op,
int len, int *min_len)
{
/* Port comparisons put the port in a follow-on inet_diag_bc_op. */
*min_len += sizeof(struct inet_diag_bc_op);
if (len < *min_len)
return false;
return true;
}
static bool valid_markcond(const struct inet_diag_bc_op *op, int len,
int *min_len)
{
*min_len += sizeof(struct inet_diag_markcond);
return len >= *min_len;
}
static int inet_diag_bc_audit(const struct nlattr *attr,
const struct sk_buff *skb)
{
bool net_admin = netlink_net_capable(skb, CAP_NET_ADMIN);
const void *bytecode, *bc;
int bytecode_len, len;
if (!attr || nla_len(attr) < sizeof(struct inet_diag_bc_op))
return -EINVAL;
bytecode = bc = nla_data(attr);
len = bytecode_len = nla_len(attr);
while (len > 0) {
int min_len = sizeof(struct inet_diag_bc_op);
const struct inet_diag_bc_op *op = bc;
switch (op->code) {
case INET_DIAG_BC_S_COND:
case INET_DIAG_BC_D_COND:
if (!valid_hostcond(bc, len, &min_len))
return -EINVAL;
break;
case INET_DIAG_BC_DEV_COND:
if (!valid_devcond(bc, len, &min_len))
return -EINVAL;
break;
case INET_DIAG_BC_S_EQ:
case INET_DIAG_BC_S_GE:
case INET_DIAG_BC_S_LE:
case INET_DIAG_BC_D_EQ:
case INET_DIAG_BC_D_GE:
case INET_DIAG_BC_D_LE:
if (!valid_port_comparison(bc, len, &min_len))
return -EINVAL;
break;
case INET_DIAG_BC_MARK_COND:
if (!net_admin)
return -EPERM;
if (!valid_markcond(bc, len, &min_len))
return -EINVAL;
break;
case INET_DIAG_BC_AUTO:
case INET_DIAG_BC_JMP:
case INET_DIAG_BC_NOP:
break;
default:
return -EINVAL;
}
if (op->code != INET_DIAG_BC_NOP) {
if (op->no < min_len || op->no > len + 4 || op->no & 3)
return -EINVAL;
if (op->no < len &&
!valid_cc(bytecode, bytecode_len, len - op->no))
return -EINVAL;
}
if (op->yes < min_len || op->yes > len + 4 || op->yes & 3)
return -EINVAL;
bc += op->yes;
len -= op->yes;
}
return len == 0 ? 0 : -EINVAL;
}
static int inet_csk_diag_dump(struct sock *sk,
struct sk_buff *skb,
struct netlink_callback *cb,
const struct inet_diag_req_v2 *r,
const struct nlattr *bc,
bool net_admin)
{
if (!inet_diag_bc_sk(bc, sk))
return 0;
return inet_csk_diag_fill(sk, skb, r,
sk_user_ns(NETLINK_CB(cb->skb).sk),
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh,
net_admin);
}
static void twsk_build_assert(void)
{
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_family) !=
offsetof(struct sock, sk_family));
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_num) !=
offsetof(struct inet_sock, inet_num));
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_dport) !=
offsetof(struct inet_sock, inet_dport));
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_rcv_saddr) !=
offsetof(struct inet_sock, inet_rcv_saddr));
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_daddr) !=
offsetof(struct inet_sock, inet_daddr));
#if IS_ENABLED(CONFIG_IPV6)
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_v6_rcv_saddr) !=
offsetof(struct sock, sk_v6_rcv_saddr));
BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_v6_daddr) !=
offsetof(struct sock, sk_v6_daddr));
#endif
}
void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb,
struct netlink_callback *cb,
const struct inet_diag_req_v2 *r, struct nlattr *bc)
{
bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
struct net *net = sock_net(skb->sk);
u32 idiag_states = r->idiag_states;
int i, num, s_i, s_num;
struct sock *sk;
if (idiag_states & TCPF_SYN_RECV)
idiag_states |= TCPF_NEW_SYN_RECV;
s_i = cb->args[1];
s_num = num = cb->args[2];
if (cb->args[0] == 0) {
if (!(idiag_states & TCPF_LISTEN) || r->id.idiag_dport)
goto skip_listen_ht;
for (i = s_i; i < INET_LHTABLE_SIZE; i++) {
struct inet_listen_hashbucket *ilb;
num = 0;
ilb = &hashinfo->listening_hash[i];
spin_lock(&ilb->lock);
sk_for_each(sk, &ilb->head) {
struct inet_sock *inet = inet_sk(sk);
if (!net_eq(sock_net(sk), net))
continue;
if (num < s_num) {
num++;
continue;
}
if (r->sdiag_family != AF_UNSPEC &&
sk->sk_family != r->sdiag_family)
goto next_listen;
if (r->id.idiag_sport != inet->inet_sport &&
r->id.idiag_sport)
goto next_listen;
if (inet_csk_diag_dump(sk, skb, cb, r,
bc, net_admin) < 0) {
spin_unlock(&ilb->lock);
goto done;
}
next_listen:
++num;
}
spin_unlock(&ilb->lock);
s_num = 0;
}
skip_listen_ht:
cb->args[0] = 1;
s_i = num = s_num = 0;
}
if (!(idiag_states & ~TCPF_LISTEN))
goto out;
#define SKARR_SZ 16
for (i = s_i; i <= hashinfo->ehash_mask; i++) {
struct inet_ehash_bucket *head = &hashinfo->ehash[i];
spinlock_t *lock = inet_ehash_lockp(hashinfo, i);
struct hlist_nulls_node *node;
struct sock *sk_arr[SKARR_SZ];
int num_arr[SKARR_SZ];
int idx, accum, res;
if (hlist_nulls_empty(&head->chain))
continue;
if (i > s_i)
s_num = 0;
next_chunk:
num = 0;
accum = 0;
spin_lock_bh(lock);
sk_nulls_for_each(sk, node, &head->chain) {
int state;
if (!net_eq(sock_net(sk), net))
continue;
if (num < s_num)
goto next_normal;
state = (sk->sk_state == TCP_TIME_WAIT) ?
inet_twsk(sk)->tw_substate : sk->sk_state;
if (!(idiag_states & (1 << state)))
goto next_normal;
if (r->sdiag_family != AF_UNSPEC &&
sk->sk_family != r->sdiag_family)
goto next_normal;
if (r->id.idiag_sport != htons(sk->sk_num) &&
r->id.idiag_sport)
goto next_normal;
if (r->id.idiag_dport != sk->sk_dport &&
r->id.idiag_dport)
goto next_normal;
twsk_build_assert();
if (!inet_diag_bc_sk(bc, sk))
goto next_normal;
sock_hold(sk);
num_arr[accum] = num;
sk_arr[accum] = sk;
if (++accum == SKARR_SZ)
break;
next_normal:
++num;
}
spin_unlock_bh(lock);
res = 0;
for (idx = 0; idx < accum; idx++) {
if (res >= 0) {
res = sk_diag_fill(sk_arr[idx], skb, r,
sk_user_ns(NETLINK_CB(cb->skb).sk),
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, NLM_F_MULTI,
cb->nlh, net_admin);
if (res < 0)
num = num_arr[idx];
}
sock_gen_put(sk_arr[idx]);
}
if (res < 0)
break;
cond_resched();
if (accum == SKARR_SZ) {
s_num = num + 1;
goto next_chunk;
}
}
done:
cb->args[1] = i;
cb->args[2] = num;
out:
;
}
EXPORT_SYMBOL_GPL(inet_diag_dump_icsk);
static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
const struct inet_diag_req_v2 *r,
struct nlattr *bc)
{
const struct inet_diag_handler *handler;
int err = 0;
handler = inet_diag_lock_handler(r->sdiag_protocol);
if (!IS_ERR(handler))
handler->dump(skb, cb, r, bc);
else
err = PTR_ERR(handler);
inet_diag_unlock_handler(handler);
return err ? : skb->len;
}
static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
int hdrlen = sizeof(struct inet_diag_req_v2);
struct nlattr *bc = NULL;
if (nlmsg_attrlen(cb->nlh, hdrlen))
bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE);
return __inet_diag_dump(skb, cb, nlmsg_data(cb->nlh), bc);
}
static int inet_diag_type2proto(int type)
{
switch (type) {
case TCPDIAG_GETSOCK:
return IPPROTO_TCP;
case DCCPDIAG_GETSOCK:
return IPPROTO_DCCP;
default:
return 0;
}
}
static int inet_diag_dump_compat(struct sk_buff *skb,
struct netlink_callback *cb)
{
struct inet_diag_req *rc = nlmsg_data(cb->nlh);
int hdrlen = sizeof(struct inet_diag_req);
struct inet_diag_req_v2 req;
struct nlattr *bc = NULL;
req.sdiag_family = AF_UNSPEC; /* compatibility */
req.sdiag_protocol = inet_diag_type2proto(cb->nlh->nlmsg_type);
req.idiag_ext = rc->idiag_ext;
req.idiag_states = rc->idiag_states;
req.id = rc->id;
if (nlmsg_attrlen(cb->nlh, hdrlen))
bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE);
return __inet_diag_dump(skb, cb, &req, bc);
}
static int inet_diag_get_exact_compat(struct sk_buff *in_skb,
const struct nlmsghdr *nlh)
{
struct inet_diag_req *rc = nlmsg_data(nlh);
struct inet_diag_req_v2 req;
req.sdiag_family = rc->idiag_family;
req.sdiag_protocol = inet_diag_type2proto(nlh->nlmsg_type);
req.idiag_ext = rc->idiag_ext;
req.idiag_states = rc->idiag_states;
req.id = rc->id;
return inet_diag_cmd_exact(SOCK_DIAG_BY_FAMILY, in_skb, nlh, &req);
}
static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh)
{
int hdrlen = sizeof(struct inet_diag_req);
struct net *net = sock_net(skb->sk);
if (nlh->nlmsg_type >= INET_DIAG_GETSOCK_MAX ||
nlmsg_len(nlh) < hdrlen)
return -EINVAL;
if (nlh->nlmsg_flags & NLM_F_DUMP) {
if (nlmsg_attrlen(nlh, hdrlen)) {
struct nlattr *attr;
int err;
attr = nlmsg_find_attr(nlh, hdrlen,
INET_DIAG_REQ_BYTECODE);
err = inet_diag_bc_audit(attr, skb);
if (err)
return err;
}
{
struct netlink_dump_control c = {
.dump = inet_diag_dump_compat,
};
return netlink_dump_start(net->diag_nlsk, skb, nlh, &c);
}
}
return inet_diag_get_exact_compat(skb, nlh);
}
static int inet_diag_handler_cmd(struct sk_buff *skb, struct nlmsghdr *h)
{
int hdrlen = sizeof(struct inet_diag_req_v2);
struct net *net = sock_net(skb->sk);
if (nlmsg_len(h) < hdrlen)
return -EINVAL;
if (h->nlmsg_type == SOCK_DIAG_BY_FAMILY &&
h->nlmsg_flags & NLM_F_DUMP) {
if (nlmsg_attrlen(h, hdrlen)) {
struct nlattr *attr;
int err;
attr = nlmsg_find_attr(h, hdrlen,
INET_DIAG_REQ_BYTECODE);
err = inet_diag_bc_audit(attr, skb);
if (err)
return err;
}
{
struct netlink_dump_control c = {
.dump = inet_diag_dump,
};
return netlink_dump_start(net->diag_nlsk, skb, h, &c);
}
}
return inet_diag_cmd_exact(h->nlmsg_type, skb, h, nlmsg_data(h));
}
static
int inet_diag_handler_get_info(struct sk_buff *skb, struct sock *sk)
{
const struct inet_diag_handler *handler;
struct nlmsghdr *nlh;
struct nlattr *attr;
struct inet_diag_msg *r;
void *info = NULL;
int err = 0;
nlh = nlmsg_put(skb, 0, 0, SOCK_DIAG_BY_FAMILY, sizeof(*r), 0);
if (!nlh)
return -ENOMEM;
r = nlmsg_data(nlh);
memset(r, 0, sizeof(*r));
inet_diag_msg_common_fill(r, sk);
if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_STREAM)
r->id.idiag_sport = inet_sk(sk)->inet_sport;
r->idiag_state = sk->sk_state;
if ((err = nla_put_u8(skb, INET_DIAG_PROTOCOL, sk->sk_protocol))) {
nlmsg_cancel(skb, nlh);
return err;
}
handler = inet_diag_lock_handler(sk->sk_protocol);
if (IS_ERR(handler)) {
inet_diag_unlock_handler(handler);
nlmsg_cancel(skb, nlh);
return PTR_ERR(handler);
}
attr = handler->idiag_info_size
? nla_reserve_64bit(skb, INET_DIAG_INFO,
handler->idiag_info_size,
INET_DIAG_PAD)
: NULL;
if (attr)
info = nla_data(attr);
handler->idiag_get_info(sk, r, info);
inet_diag_unlock_handler(handler);
nlmsg_end(skb, nlh);
return 0;
}
static const struct sock_diag_handler inet_diag_handler = {
.family = AF_INET,
.dump = inet_diag_handler_cmd,
.get_info = inet_diag_handler_get_info,
.destroy = inet_diag_handler_cmd,
};
static const struct sock_diag_handler inet6_diag_handler = {
.family = AF_INET6,
.dump = inet_diag_handler_cmd,
.get_info = inet_diag_handler_get_info,
.destroy = inet_diag_handler_cmd,
};
int inet_diag_register(const struct inet_diag_handler *h)
{
const __u16 type = h->idiag_type;
int err = -EINVAL;
if (type >= IPPROTO_MAX)
goto out;
mutex_lock(&inet_diag_table_mutex);
err = -EEXIST;
if (!inet_diag_table[type]) {
inet_diag_table[type] = h;
err = 0;
}
mutex_unlock(&inet_diag_table_mutex);
out:
return err;
}
EXPORT_SYMBOL_GPL(inet_diag_register);
void inet_diag_unregister(const struct inet_diag_handler *h)
{
const __u16 type = h->idiag_type;
if (type >= IPPROTO_MAX)
return;
mutex_lock(&inet_diag_table_mutex);
inet_diag_table[type] = NULL;
mutex_unlock(&inet_diag_table_mutex);
}
EXPORT_SYMBOL_GPL(inet_diag_unregister);
static int __init inet_diag_init(void)
{
const int inet_diag_table_size = (IPPROTO_MAX *
sizeof(struct inet_diag_handler *));
int err = -ENOMEM;
inet_diag_table = kzalloc(inet_diag_table_size, GFP_KERNEL);
if (!inet_diag_table)
goto out;
err = sock_diag_register(&inet_diag_handler);
if (err)
goto out_free_nl;
err = sock_diag_register(&inet6_diag_handler);
if (err)
goto out_free_inet;
sock_diag_register_inet_compat(inet_diag_rcv_msg_compat);
out:
return err;
out_free_inet:
sock_diag_unregister(&inet_diag_handler);
out_free_nl:
kfree(inet_diag_table);
goto out;
}
static void __exit inet_diag_exit(void)
{
sock_diag_unregister(&inet6_diag_handler);
sock_diag_unregister(&inet_diag_handler);
sock_diag_unregister_inet_compat(inet_diag_rcv_msg_compat);
kfree(inet_diag_table);
}
module_init(inet_diag_init);
module_exit(inet_diag_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2 /* AF_INET */);
MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10 /* AF_INET6 */);