Calling setsockopt with IPV6_JOIN_ANYCAST or IPV6_LEAVE_ANYCAST
triggers the assertion in addrconf_join_solict()/addrconf_leave_solict()
ipv6_sock_ac_join(), ipv6_sock_ac_drop(), ipv6_sock_ac_close() need to
take RTNL before calling ipv6_dev_ac_inc/dec. Same thing with
ipv6_sock_mc_join(), ipv6_sock_mc_drop(), ipv6_sock_mc_close() before
calling ipv6_dev_mc_inc/dec.
This patch moves ASSERT_RTNL() up a level in the call stack.
Signed-off-by: Cong Wang <xiyou.wangc...@gmail.com>
Signed-off-by: Sabrina Dubroca <s...@queasysnail.net>
Reported-by: Tommi Rantala <tt.rant...@gmail.com>
---
I included Cong's Signed-off-by for the first part of the patch,
I hope that's OK.
This patch is based on -next, but since the assertion can also be
triggered on a current kernel (tested on a 3.16), I think it should
also go in stable.
include/linux/netdevice.h | 4 ++--
net/core/dev.c | 11 ++++++-----
net/ipv6/addrconf.c | 15 +++++----------
net/ipv6/anycast.c | 30 +++++++++++++++++++-----------
net/ipv6/mcast.c | 16 ++++++++++++++++
5 files changed, 48 insertions(+), 28 deletions(-)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 429801370d0c..1ae0e745b1b1 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2077,8 +2077,8 @@ void __dev_remove_pack(struct packet_type *pt);
void dev_add_offload(struct packet_offload *po);
void dev_remove_offload(struct packet_offload *po);
-struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short flags,
- unsigned short mask);
+struct net_device *dev_get_by_flags(struct net *net, unsigned short flags,
+ unsigned short mask);
struct net_device *dev_get_by_name(struct net *net, const char *name);
struct net_device *dev_get_by_name_rcu(struct net *net, const char *name);
struct net_device *__dev_get_by_name(struct net *net, const char *name);
diff --git a/net/core/dev.c b/net/core/dev.c
index 443b814db05b..8fede6ef4a39 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -897,23 +897,24 @@ struct net_device *dev_getfirstbyhwtype(struct net *net,
unsigned short type)
EXPORT_SYMBOL(dev_getfirstbyhwtype);
/**
- * dev_get_by_flags_rcu - find any device with given flags
+ * dev_get_by_flags - find any device with given flags
* @net: the applicable net namespace
* @if_flags: IFF_* values
* @mask: bitmask of bits in if_flags to check
*
* Search for any interface with the given flags. Returns NULL if a device
* is not found or a pointer to the device. Must be called inside
- * rcu_read_lock(), and result refcount is unchanged.
+ * rtnl_lock(), and result refcount is unchanged.
*/
-struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short
if_flags,
+struct net_device *dev_get_by_flags(struct net *net, unsigned short if_flags,
unsigned short mask)
{
struct net_device *dev, *ret;
+ ASSERT_RTNL();
ret = NULL;
- for_each_netdev_rcu(net, dev) {
+ for_each_netdev(net, dev) {
if (((dev->flags ^ if_flags) & mask) == 0) {
ret = dev;
break;
@@ -921,7 +922,7 @@ struct net_device *dev_get_by_flags_rcu(struct net *net,
unsigned short if_flags
}
return ret;
}
-EXPORT_SYMBOL(dev_get_by_flags_rcu);
+EXPORT_SYMBOL(dev_get_by_flags);
/**
* dev_valid_name - check if name is okay for network device
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 267ce3caee24..7ada65937d23 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1690,14 +1690,12 @@ void addrconf_dad_failure(struct inet6_ifaddr *ifp)
addrconf_mod_dad_work(ifp, 0);
}
-/* Join to solicited addr multicast group. */
-
+/* Join to solicited addr multicast group.
+ * caller must hold RTNL */
void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
{
struct in6_addr maddr;
- ASSERT_RTNL();
-
if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
return;
@@ -1705,12 +1703,11 @@ void addrconf_join_solict(struct net_device *dev, const
struct in6_addr *addr)
ipv6_dev_mc_inc(dev, &maddr);
}
+/* caller must hold RTNL */
void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
{
struct in6_addr maddr;
- ASSERT_RTNL();
-
if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
return;
@@ -1718,12 +1715,11 @@ void addrconf_leave_solict(struct inet6_dev *idev,
const struct in6_addr *addr)
__ipv6_dev_mc_dec(idev, &maddr);
}
+/* caller must hold RTNL */
static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
{
struct in6_addr addr;
- ASSERT_RTNL();
-
if (ifp->prefix_len >= 127) /* RFC 6164 */
return;
ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
@@ -1732,12 +1728,11 @@ static void addrconf_join_anycast(struct inet6_ifaddr
*ifp)
ipv6_dev_ac_inc(ifp->idev->dev, &addr);
}
+/* caller must hold RTNL */
static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
{
struct in6_addr addr;
- ASSERT_RTNL();
-
if (ifp->prefix_len >= 127) /* RFC 6164 */
return;
ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
diff --git a/net/ipv6/anycast.c b/net/ipv6/anycast.c
index 210183244689..572c2faede55 100644
--- a/net/ipv6/anycast.c
+++ b/net/ipv6/anycast.c
@@ -77,7 +77,7 @@ int ipv6_sock_ac_join(struct sock *sk, int ifindex, const
struct in6_addr *addr)
pac->acl_next = NULL;
pac->acl_addr = *addr;
- rcu_read_lock();
+ rtnl_lock();
if (ifindex == 0) {
struct rt6_info *rt;
@@ -90,11 +90,11 @@ int ipv6_sock_ac_join(struct sock *sk, int ifindex, const
struct in6_addr *addr)
goto error;
} else {
/* router, no matching interface: just pick one */
- dev = dev_get_by_flags_rcu(net, IFF_UP,
- IFF_UP | IFF_LOOPBACK);
+ dev = dev_get_by_flags(net, IFF_UP,
+ IFF_UP | IFF_LOOPBACK);
}
} else
- dev = dev_get_by_index_rcu(net, ifindex);
+ dev = __dev_get_by_index(net, ifindex);
if (dev == NULL) {
err = -ENODEV;
@@ -136,7 +136,7 @@ int ipv6_sock_ac_join(struct sock *sk, int ifindex, const
struct in6_addr *addr)
}
error:
- rcu_read_unlock();
+ rtnl_unlock();
if (pac)
sock_kfree_s(sk, pac, sizeof(*pac));
return err;
@@ -171,13 +171,15 @@ int ipv6_sock_ac_drop(struct sock *sk, int ifindex, const
struct in6_addr *addr)
spin_unlock_bh(&ipv6_sk_ac_lock);
- rcu_read_lock();
- dev = dev_get_by_index_rcu(net, pac->acl_ifindex);
+ rtnl_lock();
+ dev = __dev_get_by_index(net, pac->acl_ifindex);
if (dev)
ipv6_dev_ac_dec(dev, &pac->acl_addr);
- rcu_read_unlock();
+ rtnl_unlock();
sock_kfree_s(sk, pac, sizeof(*pac));
+ if (!dev)
+ return -ENODEV;
return 0;
}
@@ -198,12 +200,12 @@ void ipv6_sock_ac_close(struct sock *sk)
spin_unlock_bh(&ipv6_sk_ac_lock);
prev_index = 0;
- rcu_read_lock();
+ rtnl_lock();
while (pac) {
struct ipv6_ac_socklist *next = pac->acl_next;
if (pac->acl_ifindex != prev_index) {
- dev = dev_get_by_index_rcu(net, pac->acl_ifindex);
+ dev = __dev_get_by_index(net, pac->acl_ifindex);
prev_index = pac->acl_ifindex;
}
if (dev)
@@ -211,7 +213,7 @@ void ipv6_sock_ac_close(struct sock *sk)
sock_kfree_s(sk, pac, sizeof(*pac));
pac = next;
}
- rcu_read_unlock();
+ rtnl_unlock();
}
static void aca_put(struct ifacaddr6 *ac)
@@ -233,6 +235,8 @@ int ipv6_dev_ac_inc(struct net_device *dev, const struct
in6_addr *addr)
struct rt6_info *rt;
int err;
+ ASSERT_RTNL();
+
idev = in6_dev_get(dev);
if (idev == NULL)
@@ -302,6 +306,8 @@ int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct
in6_addr *addr)
{
struct ifacaddr6 *aca, *prev_aca;
+ ASSERT_RTNL();
+
write_lock_bh(&idev->lock);
prev_aca = NULL;
for (aca = idev->ac_list; aca; aca = aca->aca_next) {
@@ -336,6 +342,8 @@ static int ipv6_dev_ac_dec(struct net_device *dev, const
struct in6_addr *addr)
{
struct inet6_dev *idev = __in6_dev_get(dev);
+ ASSERT_RTNL();
+
if (idev == NULL)
return -ENODEV;
return __ipv6_dev_ac_dec(idev, addr);
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 70881795da96..d73ac1ef65f2 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -172,6 +172,7 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const
struct in6_addr *addr)
mc_lst->next = NULL;
mc_lst->addr = *addr;
+ rtnl_lock();
rcu_read_lock();
if (ifindex == 0) {
struct rt6_info *rt;
@@ -185,6 +186,7 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const
struct in6_addr *addr)
if (dev == NULL) {
rcu_read_unlock();
+ rtnl_unlock();
sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
return -ENODEV;
}
@@ -202,6 +204,7 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const
struct in6_addr *addr)
if (err) {
rcu_read_unlock();
+ rtnl_unlock();
sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
return err;
}
@@ -212,6 +215,7 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const
struct in6_addr *addr)
spin_unlock(&ipv6_sk_mc_lock);
rcu_read_unlock();
+ rtnl_unlock();
return 0;
}
@@ -229,6 +233,7 @@ int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const
struct in6_addr *addr)
if (!ipv6_addr_is_multicast(addr))
return -EINVAL;
+ rtnl_lock();
spin_lock(&ipv6_sk_mc_lock);
for (lnk = &np->ipv6_mc_list;
(mc_lst = rcu_dereference_protected(*lnk,
@@ -252,12 +257,15 @@ int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const
struct in6_addr *addr)
} else
(void) ip6_mc_leave_src(sk, mc_lst, NULL);
rcu_read_unlock();
+ rtnl_unlock();
+
atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
kfree_rcu(mc_lst, rcu);
return 0;
}
}
spin_unlock(&ipv6_sk_mc_lock);
+ rtnl_unlock();
return -EADDRNOTAVAIL;
}
@@ -302,6 +310,7 @@ void ipv6_sock_mc_close(struct sock *sk)
if (!rcu_access_pointer(np->ipv6_mc_list))
return;
+ rtnl_lock();
spin_lock(&ipv6_sk_mc_lock);
while ((mc_lst = rcu_dereference_protected(np->ipv6_mc_list,
lockdep_is_held(&ipv6_sk_mc_lock))) != NULL) {
@@ -328,6 +337,7 @@ void ipv6_sock_mc_close(struct sock *sk)
spin_lock(&ipv6_sk_mc_lock);
}
spin_unlock(&ipv6_sk_mc_lock);
+ rtnl_unlock();
}
int ip6_mc_source(int add, int omode, struct sock *sk,
@@ -845,6 +855,8 @@ int ipv6_dev_mc_inc(struct net_device *dev, const struct
in6_addr *addr)
struct ifmcaddr6 *mc;
struct inet6_dev *idev;
+ ASSERT_RTNL();
+
/* we need to take a reference on idev */
idev = in6_dev_get(dev);
@@ -916,6 +928,8 @@ int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct
in6_addr *addr)
{
struct ifmcaddr6 *ma, **map;
+ ASSERT_RTNL();
+
write_lock_bh(&idev->lock);
for (map = &idev->mc_list; (ma = *map) != NULL; map = &ma->next) {
if (ipv6_addr_equal(&ma->mca_addr, addr)) {
@@ -942,6 +956,8 @@ int ipv6_dev_mc_dec(struct net_device *dev, const struct
in6_addr *addr)
struct inet6_dev *idev;
int err;
+ ASSERT_RTNL();
+
rcu_read_lock();
idev = __in6_dev_get(dev);
--
2.1.0
--
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