TWxSoftware/twx-linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Merge branch 'ipv6-lockless-dump-addrs'

Browse Source 
Eric Dumazet says:

====================
ipv6: lockless inet6_dump_addr()

This series removes RTNL locking to dump ipv6 addresses.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2024-03-08 11:15:36 +00:00
commit 570c86ed60
1 changed files with 78 additions and 90 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

168
net/ipv6/addrconf.c
View File

@ -717,7 +717,7 @@ static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
static u32 inet6_base_seq(const struct net *net) static u32 inet6_base_seq(const struct net *net)
{ {
u32 res = atomic_read(&net->ipv6.dev_addr_genid) + u32 res = atomic_read(&net->ipv6.dev_addr_genid) +
net->dev_base_seq; READ_ONCE(net->dev_base_seq);
/* Must not return 0 (see nl_dump_check_consistent()). /* Must not return 0 (see nl_dump_check_consistent()).
* Chose a value far away from 0. * Chose a value far away from 0.
@ -2728,7 +2728,7 @@ int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
if (update_lft) { if (update_lft) {
ifp->valid_lft = valid_lft; ifp->valid_lft = valid_lft;
ifp->prefered_lft = prefered_lft; ifp->prefered_lft = prefered_lft;
ifp->tstamp = now; WRITE_ONCE(ifp->tstamp, now);
flags = ifp->flags; flags = ifp->flags;
ifp->flags &= ~IFA_F_DEPRECATED; ifp->flags &= ~IFA_F_DEPRECATED;
spin_unlock_bh(&ifp->lock); spin_unlock_bh(&ifp->lock);
@ -4896,13 +4896,13 @@ static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
IFA_F_NOPREFIXROUTE); IFA_F_NOPREFIXROUTE);
ifp->flags |= cfg->ifa_flags; ifp->flags |= cfg->ifa_flags;
ifp->tstamp = jiffies; WRITE_ONCE(ifp->tstamp, jiffies);
ifp->valid_lft = cfg->valid_lft; WRITE_ONCE(ifp->valid_lft, cfg->valid_lft);
ifp->prefered_lft = cfg->preferred_lft; WRITE_ONCE(ifp->prefered_lft, cfg->preferred_lft);
ifp->ifa_proto = cfg->ifa_proto; WRITE_ONCE(ifp->ifa_proto, cfg->ifa_proto);
if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority) if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
ifp->rt_priority = cfg->rt_priority; WRITE_ONCE(ifp->rt_priority, cfg->rt_priority);
if (new_peer) if (new_peer)
ifp->peer_addr = *cfg->peer_pfx; ifp->peer_addr = *cfg->peer_pfx;
@ -5123,17 +5123,21 @@ struct inet6_fill_args {
enum addr_type_t type; enum addr_type_t type;
}; };
static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa, static int inet6_fill_ifaddr(struct sk_buff *skb,
const struct inet6_ifaddr *ifa,
struct inet6_fill_args *args) struct inet6_fill_args *args)
{ {
struct nlmsghdr *nlh; struct nlmsghdr *nlh;
u32 preferred, valid; u32 preferred, valid;
u32 flags, priority;
u8 proto;
nlh = nlmsg_put(skb, args->portid, args->seq, args->event, nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
sizeof(struct ifaddrmsg), args->flags); sizeof(struct ifaddrmsg), args->flags);
if (!nlh) if (!nlh)
return -EMSGSIZE; return -EMSGSIZE;
flags = READ_ONCE(ifa->flags);
put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope), put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
ifa->idev->dev->ifindex); ifa->idev->dev->ifindex);
@ -5141,13 +5145,14 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
goto error; goto error;
spin_lock_bh(&ifa->lock); preferred = READ_ONCE(ifa->prefered_lft);
if (!((ifa->flags&IFA_F_PERMANENT) && valid = READ_ONCE(ifa->valid_lft);
(ifa->prefered_lft == INFINITY_LIFE_TIME))) {
preferred = ifa->prefered_lft; if (!((flags & IFA_F_PERMANENT) &&
valid = ifa->valid_lft; (preferred == INFINITY_LIFE_TIME))) {
if (preferred != INFINITY_LIFE_TIME) { if (preferred != INFINITY_LIFE_TIME) {
long tval = (jiffies - ifa->tstamp)/HZ; long tval = (jiffies - READ_ONCE(ifa->tstamp)) / HZ;
if (preferred > tval) if (preferred > tval)
preferred -= tval; preferred -= tval;
else else
@ -5163,28 +5168,29 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
preferred = INFINITY_LIFE_TIME; preferred = INFINITY_LIFE_TIME;
valid = INFINITY_LIFE_TIME; valid = INFINITY_LIFE_TIME;
} }
spin_unlock_bh(&ifa->lock);
if (!ipv6_addr_any(&ifa->peer_addr)) { if (!ipv6_addr_any(&ifa->peer_addr)) {
if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 || if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0) nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
goto error; goto error;
} else } else {
if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0) if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
goto error; goto error;
}
if (ifa->rt_priority && priority = READ_ONCE(ifa->rt_priority);
nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority)) if (priority && nla_put_u32(skb, IFA_RT_PRIORITY, priority))
goto error; goto error;
if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0) if (put_cacheinfo(skb, ifa->cstamp, READ_ONCE(ifa->tstamp),
preferred, valid) < 0)
goto error; goto error;
if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0) if (nla_put_u32(skb, IFA_FLAGS, flags) < 0)
goto error; goto error;
if (ifa->ifa_proto && proto = READ_ONCE(ifa->ifa_proto);
nla_put_u8(skb, IFA_PROTO, ifa->ifa_proto)) if (proto && nla_put_u8(skb, IFA_PROTO, proto))
goto error; goto error;
nlmsg_end(skb, nlh); nlmsg_end(skb, nlh);
@ -5195,12 +5201,13 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
return -EMSGSIZE; return -EMSGSIZE;
} }
static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca, static int inet6_fill_ifmcaddr(struct sk_buff *skb,
const struct ifmcaddr6 *ifmca,
struct inet6_fill_args *args) struct inet6_fill_args *args)
{ {
struct nlmsghdr *nlh;
u8 scope = RT_SCOPE_UNIVERSE;
int ifindex = ifmca->idev->dev->ifindex; int ifindex = ifmca->idev->dev->ifindex;
u8 scope = RT_SCOPE_UNIVERSE;
struct nlmsghdr *nlh;
if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE) if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
scope = RT_SCOPE_SITE; scope = RT_SCOPE_SITE;
@ -5218,7 +5225,7 @@ static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex); put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 || if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp, put_cacheinfo(skb, ifmca->mca_cstamp, READ_ONCE(ifmca->mca_tstamp),
INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) { INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
nlmsg_cancel(skb, nlh); nlmsg_cancel(skb, nlh);
return -EMSGSIZE; return -EMSGSIZE;
@ -5228,13 +5235,14 @@ static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
return 0; return 0;
} }
static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca, static int inet6_fill_ifacaddr(struct sk_buff *skb,
const struct ifacaddr6 *ifaca,
struct inet6_fill_args *args) struct inet6_fill_args *args)
{ {
struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt); struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
int ifindex = dev ? dev->ifindex : 1; int ifindex = dev ? dev->ifindex : 1;
struct nlmsghdr *nlh;
u8 scope = RT_SCOPE_UNIVERSE; u8 scope = RT_SCOPE_UNIVERSE;
struct nlmsghdr *nlh;
if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE) if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
scope = RT_SCOPE_SITE; scope = RT_SCOPE_SITE;
@ -5252,7 +5260,7 @@ static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex); put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 || if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp, put_cacheinfo(skb, ifaca->aca_cstamp, READ_ONCE(ifaca->aca_tstamp),
INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) { INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
nlmsg_cancel(skb, nlh); nlmsg_cancel(skb, nlh);
return -EMSGSIZE; return -EMSGSIZE;
@ -5263,24 +5271,23 @@ static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
} }
/* called with rcu_read_lock() */ /* called with rcu_read_lock() */
static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb, static int in6_dump_addrs(const struct inet6_dev *idev, struct sk_buff *skb,
struct netlink_callback *cb, int s_ip_idx, struct netlink_callback *cb, int *s_ip_idx,
struct inet6_fill_args *fillargs) struct inet6_fill_args *fillargs)
{ {
struct ifmcaddr6 *ifmca; const struct ifmcaddr6 *ifmca;
struct ifacaddr6 *ifaca; const struct ifacaddr6 *ifaca;
int ip_idx = 0; int ip_idx = 0;
int err = 1; int err = 0;
read_lock_bh(&idev->lock);
switch (fillargs->type) { switch (fillargs->type) {
case UNICAST_ADDR: { case UNICAST_ADDR: {
struct inet6_ifaddr *ifa; const struct inet6_ifaddr *ifa;
fillargs->event = RTM_NEWADDR; fillargs->event = RTM_NEWADDR;
/* unicast address incl. temp addr */ /* unicast address incl. temp addr */
list_for_each_entry(ifa, &idev->addr_list, if_list) { list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
if (ip_idx < s_ip_idx) if (ip_idx < *s_ip_idx)
goto next; goto next;
err = inet6_fill_ifaddr(skb, ifa, fillargs); err = inet6_fill_ifaddr(skb, ifa, fillargs);
if (err < 0) if (err < 0)
@ -5292,27 +5299,25 @@ static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
break; break;
} }
case MULTICAST_ADDR: case MULTICAST_ADDR:
read_unlock_bh(&idev->lock);
fillargs->event = RTM_GETMULTICAST; fillargs->event = RTM_GETMULTICAST;
/* multicast address */ /* multicast address */
for (ifmca = rcu_dereference(idev->mc_list); for (ifmca = rcu_dereference(idev->mc_list);
ifmca; ifmca;
ifmca = rcu_dereference(ifmca->next), ip_idx++) { ifmca = rcu_dereference(ifmca->next), ip_idx++) {
if (ip_idx < s_ip_idx) if (ip_idx < *s_ip_idx)
continue; continue;
err = inet6_fill_ifmcaddr(skb, ifmca, fillargs); err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
if (err < 0) if (err < 0)
break; break;
} }
read_lock_bh(&idev->lock);
break; break;
case ANYCAST_ADDR: case ANYCAST_ADDR:
fillargs->event = RTM_GETANYCAST; fillargs->event = RTM_GETANYCAST;
/* anycast address */ /* anycast address */
for (ifaca = rcu_dereference(idev->ac_list); ifaca; for (ifaca = rcu_dereference(idev->ac_list); ifaca;
ifaca = rcu_dereference(ifaca->aca_next), ip_idx++) { ifaca = rcu_dereference(ifaca->aca_next), ip_idx++) {
if (ip_idx < s_ip_idx) if (ip_idx < *s_ip_idx)
continue; continue;
err = inet6_fill_ifacaddr(skb, ifaca, fillargs); err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
if (err < 0) if (err < 0)
@ -5322,8 +5327,7 @@ static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
default: default:
break; break;
} }
read_unlock_bh(&idev->lock); *s_ip_idx = err ? ip_idx : 0;
cb->args[2] = ip_idx;
return err; return err;
} }
@ -5386,6 +5390,7 @@ static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb, static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
enum addr_type_t type) enum addr_type_t type)
{ {
struct net *tgt_net = sock_net(skb->sk);
const struct nlmsghdr *nlh = cb->nlh; const struct nlmsghdr *nlh = cb->nlh;
struct inet6_fill_args fillargs = { struct inet6_fill_args fillargs = {
.portid = NETLINK_CB(cb->skb).portid, .portid = NETLINK_CB(cb->skb).portid,
@ -5394,72 +5399,52 @@ static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
.netnsid = -1, .netnsid = -1,
.type = type, .type = type,
}; };
struct net *tgt_net = sock_net(skb->sk); struct {
int idx, s_idx, s_ip_idx; unsigned long ifindex;
int h, s_h; int ip_idx;
} *ctx = (void *)cb->ctx;
struct net_device *dev; struct net_device *dev;
struct inet6_dev *idev; struct inet6_dev *idev;
struct hlist_head *head;
int err = 0; int err = 0;
s_h = cb->args[0];
s_idx = idx = cb->args[1];
s_ip_idx = cb->args[2];
rcu_read_lock(); rcu_read_lock();
if (cb->strict_check) { if (cb->strict_check) {
err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net, err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
skb->sk, cb); skb->sk, cb);
if (err < 0) if (err < 0)
goto put_tgt_net; goto done;
err = 0; err = 0;
if (fillargs.ifindex) { if (fillargs.ifindex) {
dev = __dev_get_by_index(tgt_net, fillargs.ifindex); err = -ENODEV;
if (!dev) { dev = dev_get_by_index_rcu(tgt_net, fillargs.ifindex);
err = -ENODEV; if (!dev)
goto put_tgt_net; goto done;
}
idev = __in6_dev_get(dev); idev = __in6_dev_get(dev);
if (idev) { if (idev)
err = in6_dump_addrs(idev, skb, cb, s_ip_idx, err = in6_dump_addrs(idev, skb, cb,
&ctx->ip_idx,
&fillargs); &fillargs);
if (err > 0) goto done;
err = 0;
}
goto put_tgt_net;
} }
} }
cb->seq = inet6_base_seq(tgt_net); cb->seq = inet6_base_seq(tgt_net);
for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) { for_each_netdev_dump(tgt_net, dev, ctx->ifindex) {
idx = 0; idev = __in6_dev_get(dev);
head = &tgt_net->dev_index_head[h]; if (!idev)
hlist_for_each_entry_rcu(dev, head, index_hlist) { continue;
if (idx < s_idx) err = in6_dump_addrs(idev, skb, cb, &ctx->ip_idx,
goto cont; &fillargs);
if (h > s_h || idx > s_idx) if (err < 0)
s_ip_idx = 0; goto done;
idev = __in6_dev_get(dev);
if (!idev)
goto cont;
if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
&fillargs) < 0)
goto done;
cont:
idx++;
}
} }
done: done:
cb->args[0] = h;
cb->args[1] = idx;
put_tgt_net:
rcu_read_unlock(); rcu_read_unlock();
if (fillargs.netnsid >= 0) if (fillargs.netnsid >= 0)
put_net(tgt_net); put_net(tgt_net);
return skb->len ? : err; return err;
} }
static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb) static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
@ -7469,15 +7454,18 @@ int __init addrconf_init(void)
goto errout; goto errout;
err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR, err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
inet6_rtm_getaddr, inet6_dump_ifaddr, inet6_rtm_getaddr, inet6_dump_ifaddr,
RTNL_FLAG_DOIT_UNLOCKED); RTNL_FLAG_DOIT_UNLOCKED |
RTNL_FLAG_DUMP_UNLOCKED);
if (err < 0) if (err < 0)
goto errout; goto errout;
err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST, err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
NULL, inet6_dump_ifmcaddr, 0); NULL, inet6_dump_ifmcaddr,
RTNL_FLAG_DUMP_UNLOCKED);
if (err < 0) if (err < 0)
goto errout; goto errout;
err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST, err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
NULL, inet6_dump_ifacaddr, 0); NULL, inet6_dump_ifacaddr,
RTNL_FLAG_DUMP_UNLOCKED);
if (err < 0) if (err < 0)
goto errout; goto errout;
err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF, err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,