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linux/net/ipv4/ipmr_base.c

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/* Linux multicast routing support
* Common logic shared by IPv4 [ipmr] and IPv6 [ip6mr] implementation
*/
#include <linux/rhashtable.h>
#include <linux/mroute_base.h>
/* Sets everything common except 'dev', since that is done under locking */
void vif_device_init(struct vif_device *v,
struct net_device *dev,
unsigned long rate_limit,
unsigned char threshold,
unsigned short flags,
unsigned short get_iflink_mask)
{
RCU_INIT_POINTER(v->dev, NULL);
v->bytes_in = 0;
v->bytes_out = 0;
v->pkt_in = 0;
v->pkt_out = 0;
v->rate_limit = rate_limit;
v->flags = flags;
v->threshold = threshold;
if (v->flags & get_iflink_mask)
v->link = dev_get_iflink(dev);
else
v->link = dev->ifindex;
}
EXPORT_SYMBOL(vif_device_init);
struct mr_table *
mr_table_alloc(struct net *net, u32 id,
struct mr_table_ops *ops,
void (*expire_func)(struct timer_list *t),
void (*table_set)(struct mr_table *mrt,
struct net *net))
{
struct mr_table *mrt;
int err;
mrt = kzalloc(sizeof(*mrt), GFP_KERNEL);
if (!mrt)
return ERR_PTR(-ENOMEM);
mrt->id = id;
write_pnet(&mrt->net, net);
mrt->ops = *ops;
err = rhltable_init(&mrt->mfc_hash, mrt->ops.rht_params);
if (err) {
ipmr: properly check rhltable_init() return value commit 8fb472c09b9d ("ipmr: improve hash scalability") added a call to rhltable_init() without checking its return value. This problem was then later copied to IPv6 and factorized in commit 0bbbf0e7d0e7 ("ipmr, ip6mr: Unite creation of new mr_table") kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 31552 Comm: syz-executor7 Not tainted 4.17.0-rc5+ #60 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rht_key_hashfn include/linux/rhashtable.h:277 [inline] RIP: 0010:__rhashtable_lookup include/linux/rhashtable.h:630 [inline] RIP: 0010:rhltable_lookup include/linux/rhashtable.h:716 [inline] RIP: 0010:mr_mfc_find_parent+0x2ad/0xbb0 net/ipv4/ipmr_base.c:63 RSP: 0018:ffff8801826aef70 EFLAGS: 00010203 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffc90001ea0000 RDX: 0000000000000079 RSI: ffffffff8661e859 RDI: 000000000000000c RBP: ffff8801826af1c0 R08: ffff8801b2212000 R09: ffffed003b5e46c2 R10: ffffed003b5e46c2 R11: ffff8801daf23613 R12: dffffc0000000000 R13: ffff8801826af198 R14: ffff8801cf8225c0 R15: ffff8801826af658 FS: 00007ff7fa732700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000003ffffff9c CR3: 00000001b0210000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ip6mr_cache_find_parent net/ipv6/ip6mr.c:981 [inline] ip6mr_mfc_delete+0x1fe/0x6b0 net/ipv6/ip6mr.c:1221 ip6_mroute_setsockopt+0x15c6/0x1d70 net/ipv6/ip6mr.c:1698 do_ipv6_setsockopt.isra.9+0x422/0x4660 net/ipv6/ipv6_sockglue.c:163 ipv6_setsockopt+0xbd/0x170 net/ipv6/ipv6_sockglue.c:922 rawv6_setsockopt+0x59/0x140 net/ipv6/raw.c:1060 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3039 __sys_setsockopt+0x1bd/0x390 net/socket.c:1903 __do_sys_setsockopt net/socket.c:1914 [inline] __se_sys_setsockopt net/socket.c:1911 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1911 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 8fb472c09b9d ("ipmr: improve hash scalability") Fixes: 0bbbf0e7d0e7 ("ipmr, ip6mr: Unite creation of new mr_table") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Cc: Yuval Mintz <yuvalm@mellanox.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-21 10:51:53 -07:00
kfree(mrt);
return ERR_PTR(err);
ipmr: properly check rhltable_init() return value commit 8fb472c09b9d ("ipmr: improve hash scalability") added a call to rhltable_init() without checking its return value. This problem was then later copied to IPv6 and factorized in commit 0bbbf0e7d0e7 ("ipmr, ip6mr: Unite creation of new mr_table") kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 31552 Comm: syz-executor7 Not tainted 4.17.0-rc5+ #60 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rht_key_hashfn include/linux/rhashtable.h:277 [inline] RIP: 0010:__rhashtable_lookup include/linux/rhashtable.h:630 [inline] RIP: 0010:rhltable_lookup include/linux/rhashtable.h:716 [inline] RIP: 0010:mr_mfc_find_parent+0x2ad/0xbb0 net/ipv4/ipmr_base.c:63 RSP: 0018:ffff8801826aef70 EFLAGS: 00010203 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffc90001ea0000 RDX: 0000000000000079 RSI: ffffffff8661e859 RDI: 000000000000000c RBP: ffff8801826af1c0 R08: ffff8801b2212000 R09: ffffed003b5e46c2 R10: ffffed003b5e46c2 R11: ffff8801daf23613 R12: dffffc0000000000 R13: ffff8801826af198 R14: ffff8801cf8225c0 R15: ffff8801826af658 FS: 00007ff7fa732700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000003ffffff9c CR3: 00000001b0210000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ip6mr_cache_find_parent net/ipv6/ip6mr.c:981 [inline] ip6mr_mfc_delete+0x1fe/0x6b0 net/ipv6/ip6mr.c:1221 ip6_mroute_setsockopt+0x15c6/0x1d70 net/ipv6/ip6mr.c:1698 do_ipv6_setsockopt.isra.9+0x422/0x4660 net/ipv6/ipv6_sockglue.c:163 ipv6_setsockopt+0xbd/0x170 net/ipv6/ipv6_sockglue.c:922 rawv6_setsockopt+0x59/0x140 net/ipv6/raw.c:1060 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3039 __sys_setsockopt+0x1bd/0x390 net/socket.c:1903 __do_sys_setsockopt net/socket.c:1914 [inline] __se_sys_setsockopt net/socket.c:1911 [inline] __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1911 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 8fb472c09b9d ("ipmr: improve hash scalability") Fixes: 0bbbf0e7d0e7 ("ipmr, ip6mr: Unite creation of new mr_table") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Cc: Yuval Mintz <yuvalm@mellanox.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-21 10:51:53 -07:00
}
INIT_LIST_HEAD(&mrt->mfc_cache_list);
INIT_LIST_HEAD(&mrt->mfc_unres_queue);
timer_setup(&mrt->ipmr_expire_timer, expire_func, 0);
mrt->mroute_reg_vif_num = -1;
table_set(mrt, net);
return mrt;
}
EXPORT_SYMBOL(mr_table_alloc);
void *mr_mfc_find_parent(struct mr_table *mrt, void *hasharg, int parent)
{
struct rhlist_head *tmp, *list;
struct mr_mfc *c;
list = rhltable_lookup(&mrt->mfc_hash, hasharg, *mrt->ops.rht_params);
rhl_for_each_entry_rcu(c, tmp, list, mnode)
if (parent == -1 || parent == c->mfc_parent)
return c;
return NULL;
}
EXPORT_SYMBOL(mr_mfc_find_parent);
void *mr_mfc_find_any_parent(struct mr_table *mrt, int vifi)
{
struct rhlist_head *tmp, *list;
struct mr_mfc *c;
list = rhltable_lookup(&mrt->mfc_hash, mrt->ops.cmparg_any,
*mrt->ops.rht_params);
rhl_for_each_entry_rcu(c, tmp, list, mnode)
if (c->mfc_un.res.ttls[vifi] < 255)
return c;
return NULL;
}
EXPORT_SYMBOL(mr_mfc_find_any_parent);
void *mr_mfc_find_any(struct mr_table *mrt, int vifi, void *hasharg)
{
struct rhlist_head *tmp, *list;
struct mr_mfc *c, *proxy;
list = rhltable_lookup(&mrt->mfc_hash, hasharg, *mrt->ops.rht_params);
rhl_for_each_entry_rcu(c, tmp, list, mnode) {
if (c->mfc_un.res.ttls[vifi] < 255)
return c;
/* It's ok if the vifi is part of the static tree */
proxy = mr_mfc_find_any_parent(mrt, c->mfc_parent);
if (proxy && proxy->mfc_un.res.ttls[vifi] < 255)
return c;
}
return mr_mfc_find_any_parent(mrt, vifi);
}
EXPORT_SYMBOL(mr_mfc_find_any);
#ifdef CONFIG_PROC_FS
void *mr_vif_seq_idx(struct net *net, struct mr_vif_iter *iter, loff_t pos)
{
struct mr_table *mrt = iter->mrt;
for (iter->ct = 0; iter->ct < mrt->maxvif; ++iter->ct) {
if (!VIF_EXISTS(mrt, iter->ct))
continue;
if (pos-- == 0)
return &mrt->vif_table[iter->ct];
}
return NULL;
}
EXPORT_SYMBOL(mr_vif_seq_idx);
void *mr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct mr_vif_iter *iter = seq->private;
struct net *net = seq_file_net(seq);
struct mr_table *mrt = iter->mrt;
++*pos;
if (v == SEQ_START_TOKEN)
return mr_vif_seq_idx(net, iter, 0);
while (++iter->ct < mrt->maxvif) {
if (!VIF_EXISTS(mrt, iter->ct))
continue;
return &mrt->vif_table[iter->ct];
}
return NULL;
}
EXPORT_SYMBOL(mr_vif_seq_next);
void *mr_mfc_seq_idx(struct net *net,
struct mr_mfc_iter *it, loff_t pos)
{
struct mr_table *mrt = it->mrt;
struct mr_mfc *mfc;
rcu_read_lock();
it->cache = &mrt->mfc_cache_list;
list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list)
if (pos-- == 0)
return mfc;
rcu_read_unlock();
spin_lock_bh(it->lock);
it->cache = &mrt->mfc_unres_queue;
list_for_each_entry(mfc, it->cache, list)
if (pos-- == 0)
return mfc;
spin_unlock_bh(it->lock);
it->cache = NULL;
return NULL;
}
EXPORT_SYMBOL(mr_mfc_seq_idx);
void *mr_mfc_seq_next(struct seq_file *seq, void *v,
loff_t *pos)
{
struct mr_mfc_iter *it = seq->private;
struct net *net = seq_file_net(seq);
struct mr_table *mrt = it->mrt;
struct mr_mfc *c = v;
++*pos;
if (v == SEQ_START_TOKEN)
return mr_mfc_seq_idx(net, seq->private, 0);
if (c->list.next != it->cache)
return list_entry(c->list.next, struct mr_mfc, list);
if (it->cache == &mrt->mfc_unres_queue)
goto end_of_list;
/* exhausted cache_array, show unresolved */
rcu_read_unlock();
it->cache = &mrt->mfc_unres_queue;
spin_lock_bh(it->lock);
if (!list_empty(it->cache))
return list_first_entry(it->cache, struct mr_mfc, list);
end_of_list:
spin_unlock_bh(it->lock);
it->cache = NULL;
return NULL;
}
EXPORT_SYMBOL(mr_mfc_seq_next);
#endif
int mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
struct mr_mfc *c, struct rtmsg *rtm)
{
struct net_device *vif_dev;
struct rta_mfc_stats mfcs;
struct nlattr *mp_attr;
struct rtnexthop *nhp;
unsigned long lastuse;
int ct;
/* If cache is unresolved, don't try to parse IIF and OIF */
if (c->mfc_parent >= MAXVIFS) {
rtm->rtm_flags |= RTNH_F_UNRESOLVED;
return -ENOENT;
}
rcu_read_lock();
vif_dev = rcu_dereference(mrt->vif_table[c->mfc_parent].dev);
if (vif_dev && nla_put_u32(skb, RTA_IIF, vif_dev->ifindex) < 0) {
rcu_read_unlock();
return -EMSGSIZE;
}
rcu_read_unlock();
if (c->mfc_flags & MFC_OFFLOAD)
rtm->rtm_flags |= RTNH_F_OFFLOAD;
mp_attr = nla_nest_start_noflag(skb, RTA_MULTIPATH);
if (!mp_attr)
return -EMSGSIZE;
rcu_read_lock();
for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) {
struct vif_device *vif = &mrt->vif_table[ct];
vif_dev = rcu_dereference(vif->dev);
if (vif_dev && c->mfc_un.res.ttls[ct] < 255) {
nhp = nla_reserve_nohdr(skb, sizeof(*nhp));
if (!nhp) {
rcu_read_unlock();
nla_nest_cancel(skb, mp_attr);
return -EMSGSIZE;
}
nhp->rtnh_flags = 0;
nhp->rtnh_hops = c->mfc_un.res.ttls[ct];
nhp->rtnh_ifindex = vif_dev->ifindex;
nhp->rtnh_len = sizeof(*nhp);
}
}
rcu_read_unlock();
nla_nest_end(skb, mp_attr);
lastuse = READ_ONCE(c->mfc_un.res.lastuse);
lastuse = time_after_eq(jiffies, lastuse) ? jiffies - lastuse : 0;
mfcs.mfcs_packets = c->mfc_un.res.pkt;
mfcs.mfcs_bytes = c->mfc_un.res.bytes;
mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if;
if (nla_put_64bit(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs, RTA_PAD) ||
nla_put_u64_64bit(skb, RTA_EXPIRES, jiffies_to_clock_t(lastuse),
RTA_PAD))
return -EMSGSIZE;
rtm->rtm_type = RTN_MULTICAST;
return 1;
}
EXPORT_SYMBOL(mr_fill_mroute);
static bool mr_mfc_uses_dev(const struct mr_table *mrt,
const struct mr_mfc *c,
const struct net_device *dev)
{
int ct;
for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) {
const struct net_device *vif_dev;
const struct vif_device *vif;
vif = &mrt->vif_table[ct];
vif_dev = rcu_access_pointer(vif->dev);
if (vif_dev && c->mfc_un.res.ttls[ct] < 255 &&
vif_dev == dev)
return true;
}
return false;
}
int mr_table_dump(struct mr_table *mrt, struct sk_buff *skb,
struct netlink_callback *cb,
int (*fill)(struct mr_table *mrt, struct sk_buff *skb,
u32 portid, u32 seq, struct mr_mfc *c,
int cmd, int flags),
spinlock_t *lock, struct fib_dump_filter *filter)
{
unsigned int e = 0, s_e = cb->args[1];
unsigned int flags = NLM_F_MULTI;
struct mr_mfc *mfc;
int err;
if (filter->filter_set)
flags |= NLM_F_DUMP_FILTERED;
list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list) {
if (e < s_e)
goto next_entry;
if (filter->dev &&
!mr_mfc_uses_dev(mrt, mfc, filter->dev))
goto next_entry;
err = fill(mrt, skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, mfc, RTM_NEWROUTE, flags);
if (err < 0)
goto out;
next_entry:
e++;
}
spin_lock_bh(lock);
list_for_each_entry(mfc, &mrt->mfc_unres_queue, list) {
if (e < s_e)
goto next_entry2;
if (filter->dev &&
!mr_mfc_uses_dev(mrt, mfc, filter->dev))
goto next_entry2;
err = fill(mrt, skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, mfc, RTM_NEWROUTE, flags);
if (err < 0) {
spin_unlock_bh(lock);
goto out;
}
next_entry2:
e++;
}
spin_unlock_bh(lock);
err = 0;
out:
cb->args[1] = e;
return err;
}
EXPORT_SYMBOL(mr_table_dump);
int mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb,
struct mr_table *(*iter)(struct net *net,
struct mr_table *mrt),
int (*fill)(struct mr_table *mrt,
struct sk_buff *skb,
u32 portid, u32 seq, struct mr_mfc *c,
int cmd, int flags),
spinlock_t *lock, struct fib_dump_filter *filter)
{
unsigned int t = 0, s_t = cb->args[0];
struct net *net = sock_net(skb->sk);
struct mr_table *mrt;
int err;
/* multicast does not track protocol or have route type other
* than RTN_MULTICAST
*/
if (filter->filter_set) {
if (filter->protocol || filter->flags ||
(filter->rt_type && filter->rt_type != RTN_MULTICAST))
return skb->len;
}
rcu_read_lock();
for (mrt = iter(net, NULL); mrt; mrt = iter(net, mrt)) {
if (t < s_t)
goto next_table;
err = mr_table_dump(mrt, skb, cb, fill, lock, filter);
if (err < 0)
break;
cb->args[1] = 0;
next_table:
t++;
}
rcu_read_unlock();
cb->args[0] = t;
return skb->len;
}
EXPORT_SYMBOL(mr_rtm_dumproute);
int mr_dump(struct net *net, struct notifier_block *nb, unsigned short family,
int (*rules_dump)(struct net *net,
struct notifier_block *nb,
struct netlink_ext_ack *extack),
struct mr_table *(*mr_iter)(struct net *net,
struct mr_table *mrt),
struct netlink_ext_ack *extack)
{
struct mr_table *mrt;
int err;
err = rules_dump(net, nb, extack);
if (err)
return err;
for (mrt = mr_iter(net, NULL); mrt; mrt = mr_iter(net, mrt)) {
struct vif_device *v = &mrt->vif_table[0];
struct net_device *vif_dev;
struct mr_mfc *mfc;
int vifi;
/* Notifiy on table VIF entries */
rcu_read_lock();
for (vifi = 0; vifi < mrt->maxvif; vifi++, v++) {
vif_dev = rcu_dereference(v->dev);
if (!vif_dev)
continue;
err = mr_call_vif_notifier(nb, family,
FIB_EVENT_VIF_ADD, v,
vif_dev, vifi,
mrt->id, extack);
if (err)
break;
}
rcu_read_unlock();
if (err)
return err;
/* Notify on table MFC entries */
list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list) {
err = mr_call_mfc_notifier(nb, family,
FIB_EVENT_ENTRY_ADD,
mfc, mrt->id, extack);
if (err)
return err;
}
}
return 0;
}
EXPORT_SYMBOL(mr_dump);