Under some circumstances it is possible that no new temporary addresses
will be generated.
For instance, addrconf_prefix_rcv_add_addr() indirectly calls
ipv6_create_tempaddr(), which creates a tentative temporary address and
starts dad. Next, addrconf_prefix_rcv_add_addr() indirectly calls
addrconf_verify_rtnl(). Now, assume that the previously created temporary
address has the least preferred lifetime among all existing addresses and
is still tentative (that is, dad is still running). Hence, the next run of
addrconf_verify_rtnl() is performed when the preferred lifetime of the
temporary address ends. If dad succeeds before the next run, the temporary
address becomes deprecated during the next run, but no new temporary
address is generated.
In order to fix this, schedule the next addrconf_verify_rtnl() run slightly
before the temporary address becomes deprecated, if dad succeeded.
Signed-off-by: Marcus Huewe <suse-tux@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
When for instance a mobile Linux device roams from one access point to
another with both APs sharing the same broadcast domain and a
multicast snooping switch in between:
1) (c) <~~~> (AP1) <--[SSW]--> (AP2)
2) (AP1) <--[SSW]--> (AP2) <~~~> (c)
Then currently IPv6 multicast packets will get lost for (c) until an
MLD Querier sends its next query message. The packet loss occurs
because upon roaming the Linux host so far stayed silent regarding
MLD and the snooping switch will therefore be unaware of the
multicast topology change for a while.
This patch fixes this by always resending MLD reports when an interface
change happens, for instance from NO-CARRIER to CARRIER state.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
Just like commit 4acd4945cd ("ipv6: addrconf: Avoid calling
netdevice notifiers with RCU read-side lock"), it is unnecessary
to make addrconf_disable_change() use RCU iteration over the
netdev list, since it already holds the RTNL lock, or we may meet
Illegal context switch in RCU read-side critical section.
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implemented RFC7527 Enhanced DAD.
IPv6 duplicate address detection can fail if there is some temporary
loopback of Ethernet frames. RFC7527 solves this by including a random
nonce in the NS messages used for DAD, and if an NS is received with the
same nonce it is assumed to be a looped back DAD probe and is ignored.
RFC7527 is enabled by default. Can be disabled by setting both of
conf/{all,interface}/enhanced_dad to zero.
Signed-off-by: Erik Nordmark <nordmark@arista.com>
Signed-off-by: Bob Gilligan <gilligan@arista.com>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
udplite conflict is resolved by taking what 'net-next' did
which removed the backlog receive method assignment, since
it is no longer necessary.
Two entries were added to the non-priv ethtool operations
switch statement, one in 'net' and one in 'net-next, so
simple overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
When an ipv6 address has the tentative flag set, it can't be
used as source for egress traffic, while the associated route,
if any, can be looked up and even stored into some dst_cache.
In the latter scenario, the source ipv6 address selected and
stored in the cache is most probably wrong (e.g. with
link-local scope) and the entity using the dst_cache will
experience lack of ipv6 connectivity until said cache is
cleared or invalidated.
Overall this may cause lack of connectivity over most IPv6 tunnels
(comprising geneve and vxlan), if the first egress packet reaches
the tunnel before the DaD is completed for the used ipv6
address.
This patch bumps a new genid after that the IFA_F_TENTATIVE flag
is cleared, so that dst_cache will be invalidated on
next lookup and ipv6 connectivity restored.
Fixes: 0c1d70af92 ("net: use dst_cache for vxlan device")
Fixes: 468dfffcd7 ("geneve: add dst caching support")
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the necessary functions to compute and check the HMAC signature
of an SR-enabled packet. Two HMAC algorithms are supported: hmac(sha1) and
hmac(sha256).
In order to avoid dynamic memory allocation for each HMAC computation,
a per-cpu ring buffer is allocated for this purpose.
A new per-interface sysctl called seg6_require_hmac is added, allowing a
user-defined policy for processing HMAC-signed SR-enabled packets.
A value of -1 means that the HMAC field will always be ignored.
A value of 0 means that if an HMAC field is present, its validity will
be enforced (the packet is dropped is the signature is incorrect).
Finally, a value of 1 means that any SR-enabled packet that does not
contain an HMAC signature or whose signature is incorrect will be dropped.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement minimal support for processing of SR-enabled packets
as described in
https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-02.
This patch implements the following operations:
- Intermediate segment endpoint: incrementation of active segment and rerouting.
- Egress for SR-encapsulated packets: decapsulation of outer IPv6 header + SRH
and routing of inner packet.
- Cleanup flag support for SR-inlined packets: removal of SRH if we are the
penultimate segment endpoint.
A per-interface sysctl seg6_enabled is provided, to accept/deny SR-enabled
packets. Default is deny.
This patch does not provide support for HMAC-signed packets.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
The check for an underflow of tmp_prefered_lft is always false
because tmp_prefered_lft is unsigned. The intention of the check
was to guard against racing with an update of the
temp_prefered_lft sysctl, potentially resulting in an underflow.
As suggested by David Miller, the best way to prevent the race is
by reading the sysctl variable using READ_ONCE.
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Fixes: 76506a986d ("IPv6: fix DESYNC_FACTOR")
Signed-off-by: David S. Miller <davem@davemloft.net>
The IPv6 temporary address generation uses a variable called DESYNC_FACTOR
to prevent hosts updating the addresses at the same time. Quoting RFC 4941:
... The value DESYNC_FACTOR is a random value (different for each
client) that ensures that clients don't synchronize with each other and
generate new addresses at exactly the same time ...
DESYNC_FACTOR is defined as:
DESYNC_FACTOR -- A random value within the range 0 - MAX_DESYNC_FACTOR.
It is computed once at system start (rather than each time it is used)
and must never be greater than (TEMP_VALID_LIFETIME - REGEN_ADVANCE).
First, I believe the RFC has a typo in it and meant to say: "and must
never be greater than (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE)"
The reason is that at various places in the RFC, DESYNC_FACTOR is used in
a calculation like (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR) or
(TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE - DESYNC_FACTOR). It needs to be
smaller than (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE) for the result of
these calculations to be larger than zero. It's never used in a
calculation together with TEMP_VALID_LIFETIME.
I already submitted an errata to the rfc-editor:
https://www.rfc-editor.org/errata_search.php?rfc=4941
The Linux implementation of DESYNC_FACTOR is very wrong:
max_desync_factor is used in places DESYNC_FACTOR should be used.
max_desync_factor is initialized to the RFC-recommended value for
MAX_DESYNC_FACTOR (600) but the whole point is to get a _random_ value.
And nothing ensures that the value used is not greater than
(TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE), which leads to underflows. The
effect can easily be observed when setting the temp_prefered_lft sysctl
e.g. to 60. The preferred lifetime of the temporary addresses will be
bogus.
TEMP_PREFERRED_LIFETIME and REGEN_ADVANCE are not constants and can be
influenced by these three sysctls: regen_max_retry, dad_transmits and
temp_prefered_lft. Thus, the upper bound for desync_factor needs to be
re-calculated each time a new address is generated and if desync_factor is
larger than the new upper bound, a new random value needs to be
re-generated.
And since we already have max_desync_factor configurable per interface, we
also need to calculate and store desync_factor per interface.
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
The randomized interface identifier (rndid) was periodically updated from
the regen_timer timer. Simplify the code by updating the rndid only when
needed by ipv6_try_regen_rndid().
This makes the follow-up DESYNC_FACTOR fix much simpler. Also it fixes a
reference counting error in this error path, where an in6_dev_put was
missing:
err = addrconf_sysctl_register(ndev);
if (err) {
ipv6_mc_destroy_dev(ndev);
- del_timer(&ndev->regen_timer);
snmp6_unregister_dev(ndev);
goto err_release;
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
The goal of the patch is to fix this scenario:
ip link add dummy1 type dummy
ip link set dummy1 up
ip link set lo down ; ip link set lo up
After that sequence, the local route to the link layer address of dummy1 is
not there anymore.
When the loopback is set down, all local routes are deleted by
addrconf_ifdown()/rt6_ifdown(). At this time, the rt6_info entry still
exists, because the corresponding idev has a reference on it. After the rcu
grace period, dst_rcu_free() is called, and thus ___dst_free(), which will
set obsolete to DST_OBSOLETE_DEAD.
In this case, init_loopback() is called before dst_rcu_free(), thus
obsolete is still sets to something <= 0. So, the function doesn't add the
route again. To avoid that race, let's check the rt6 refcnt instead.
Fixes: 25fb6ca4ed ("net IPv6 : Fix broken IPv6 routing table after loopback down-up")
Fixes: a881ae1f62 ("ipv6: don't call addrconf_dst_alloc again when enable lo")
Fixes: 33d99113b1 ("ipv6: reallocate addrconf router for ipv6 address when lo device up")
Reported-by: Francesco Santoro <francesco.santoro@6wind.com>
Reported-by: Samuel Gauthier <samuel.gauthier@6wind.com>
CC: Balakumaran Kannan <Balakumaran.Kannan@ap.sony.com>
CC: Maruthi Thotad <Maruthi.Thotad@ap.sony.com>
CC: Sabrina Dubroca <sd@queasysnail.net>
CC: Hannes Frederic Sowa <hannes@stressinduktion.org>
CC: Weilong Chen <chenweilong@huawei.com>
CC: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This disallows setting /proc/sys/net/ipv6/conf/*/router_solicitations
to values below -1.
-1 continues to mean an unlimited number of retransmits.
Note: this depends on 'ipv6 addrconf: remove addrconf_sysctl_hop_limit()'
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is an effective no-op in terms of user observable behaviour.
By preventing the overwrite of non-null extra1/extra2 fields
in addrconf_sysctl() we can enable the use of proc_dointvec_minmax().
This allows us to eliminate the constant min/max (1..255) trampoline
function that is addrconf_sysctl_hop_limit().
This is nice because it simplifies the code, and allows future
sysctls with constant min/max limits to also not require trampolines.
We still can't eliminate the trampoline for mtu because it isn't
actually a constant (it depends on other tunables of the device)
and thus requires at-write-time logic to enforce range.
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Acked-by: Erik Kline <ek@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This implements:
https://tools.ietf.org/html/rfc7559
Backoff is performed according to RFC3315 section 14:
https://tools.ietf.org/html/rfc3315#section-14
We allow setting /proc/sys/net/ipv6/conf/*/router_solicitations
to a negative value meaning an unlimited number of retransmits,
and we make this the new default (inline with the RFC).
We also add a new setting:
/proc/sys/net/ipv6/conf/*/router_solicitation_max_interval
defaulting to 1 hour (per RFC recommendation).
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Acked-by: Erik Kline <ek@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The parameter items(is always ICMP6_MIB_MAX) is useless for __snmp6_fill_statsdev
Signed-off-by: Jia He <hejianet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In general, when DAD detected IPv6 duplicate address, ifp->state
will be set to INET6_IFADDR_STATE_ERRDAD and DAD is stopped by a
delayed work, the call tree should be like this:
ndisc_recv_ns
-> addrconf_dad_failure <- missing ifp put
-> addrconf_mod_dad_work
-> schedule addrconf_dad_work()
-> addrconf_dad_stop() <- missing ifp hold before call it
addrconf_dad_failure() called with ifp refcont holding but not put.
addrconf_dad_work() call addrconf_dad_stop() without extra holding
refcount. This will not cause any issue normally.
But the race between addrconf_dad_failure() and addrconf_dad_work()
may cause ifp refcount leak and netdevice can not be unregister,
dmesg show the following messages:
IPv6: eth0: IPv6 duplicate address fe80::XX:XXXX:XXXX:XX detected!
...
unregister_netdevice: waiting for eth0 to become free. Usage count = 1
Cc: stable@vger.kernel.org
Fixes: c15b1ccadb ("ipv6: move DAD and addrconf_verify processing
to workqueue")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All changes are notified, but the initial state was missing.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The 'default' value was not advertised.
Fixes: f3a1bfb11c ("rtnl/ipv6: use netconf msg to advertise forwarding status")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If DAD fails with accept_dad set to 2, global addresses and host routes
are incorrectly left in place. Even though disable_ipv6 is set,
contrary to documentation, the addresses are not dynamically deleted
from the interface. It is only on a subsequent link down/up that these
are removed. The fix is not only to set the disable_ipv6 flag, but
also to call addrconf_ifdown(), which is the action to carry out when
disabling IPv6. This results in the addresses and routes being deleted
immediately. The DAD failure for the LL addr is determined as before
via netlink, or by the absence of the LL addr (which also previously
would have had to be checked for in case of an intervening link down
and up). As the call to addrconf_ifdown() requires an rtnl lock, the
logic to disable IPv6 when DAD fails is moved to addrconf_dad_work().
Previous behavior:
root@vm1:/# sysctl net.ipv6.conf.eth3.accept_dad=2
net.ipv6.conf.eth3.accept_dad = 2
root@vm1:/# ip -6 addr add 2000::10/64 dev eth3
root@vm1:/# ip link set up eth3
root@vm1:/# ip -6 addr show dev eth3
5: eth3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qlen 1000
inet6 2000::10/64 scope global
valid_lft forever preferred_lft forever
inet6 fe80::5054:ff:fe43:dd5a/64 scope link tentative dadfailed
valid_lft forever preferred_lft forever
root@vm1:/# ip -6 route show dev eth3
2000::/64 proto kernel metric 256
fe80::/64 proto kernel metric 256
root@vm1:/# ip link set down eth3
root@vm1:/# ip link set up eth3
root@vm1:/# ip -6 addr show dev eth3
root@vm1:/# ip -6 route show dev eth3
root@vm1:/#
New behavior:
root@vm1:/# sysctl net.ipv6.conf.eth3.accept_dad=2
net.ipv6.conf.eth3.accept_dad = 2
root@vm1:/# ip -6 addr add 2000::10/64 dev eth3
root@vm1:/# ip link set up eth3
root@vm1:/# ip -6 addr show dev eth3
root@vm1:/# ip -6 route show dev eth3
root@vm1:/#
Signed-off-by: Mike Manning <mmanning@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If IPv6 is disabled when the option is set to keep IPv6
addresses on link down, userspace is unaware of this as
there is no such indication via netlink. The solution is to
remove the IPv6 addresses in this case, which results in
netlink messages indicating removal of addresses in the
usual manner. This fix also makes the behavior consistent
with the case of having IPv6 disabled first, which stops
IPv6 addresses from being added.
Fixes: f1705ec197 ("net: ipv6: Make address flushing on ifdown optional")
Signed-off-by: Mike Manning <mmanning@brocade.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using list_move() instead of list_del() + list_add().
Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Default kernel behavior is to delete IPv6 addresses on link
down, which entails deletion of the multicast and the
subnet-router anycast addresses. These deletions do not
happen with sysctl setting to keep global IPv6 addresses on
link down, so every link down/up causes an increment of the
anycast and multicast refcounts. These bogus refcounts may
stop these addrs from being removed on subsequent calls to
delete them. The solution is to leave the groups for the
multicast and subnet anycast on link down for the callflow
when global IPv6 addresses are kept.
Fixes: f1705ec197 ("net: ipv6: Make address flushing on ifdown optional")
Signed-off-by: Mike Manning <mmanning@brocade.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All inet6_netconf_notify_devconf() callers are in process context,
so we can use GFP_KERNEL allocations if we take care of not holding
a rwlock while not needed in ip6mr (we hold RTNL there)
Fixes: d67b8c616b ("netconf: advertise mc_forwarding status")
Fixes: f3a1bfb11c ("rtnl/ipv6: use netconf msg to advertise forwarding status")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IPv6 version of 3f2fb9a834 ("net: l3mdev: address selection should only
consider devices in L3 domain") and the follow up commit, a17b693cdd876
("net: l3mdev: prefer VRF master for source address selection").
That is, if outbound device is given then the address preference order
is an address from that device, an address from the master device if it
is enslaved, and then an address from a device in the same L3 domain.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch exports some neighbour discovery functions which can be used
by 6lowpan neighbour discovery ops functionality then.
Cc: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces neighbour discovery ops callback structure. The
idea is to separate the handling for 6LoWPAN into the 6lowpan module.
These callback offers 6lowpan different handling, such as 802.15.4 short
address handling or RFC6775 (Neighbor Discovery Optimization for IPv6
over 6LoWPANs).
Cc: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch moves the functionality to add a RA PIO prefix generated
address in an own function. This move prepares to add a hook for
adding a second address for a second link-layer address. E.g. short
address for 802.15.4 6LoWPAN.
Cc: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the autoconfiguration if a valid 802.15.4 short address
is available for 802.15.4 6LoWPAN interfaces.
Cc: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
L3 master devices are virtual devices similar to the loopback
device. Link local and multicast routes for these devices do
not make sense. The ipv6 addrconf code already skips adding a
linklocal address; do the same for the mcast route.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Minor overlapping changes in the conflicts.
In the macsec case, the change of the default ID macro
name overlapped with the 64-bit netlink attribute alignment
fixes in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
It was a simple idea -- save IPv6 configured addresses on a link down
so that IPv6 behaves similar to IPv4. As always the devil is in the
details and the IPv6 stack as too many behavioral differences from IPv4
making the simple idea more complicated than it needs to be.
The current implementation for keeping IPv6 addresses can panic or spit
out a warning in one of many paths:
1. IPv6 route gets an IPv4 route as its 'next' which causes a panic in
rt6_fill_node while handling a route dump request.
2. rt->dst.obsolete is set to DST_OBSOLETE_DEAD hitting the WARN_ON in
fib6_del
3. Panic in fib6_purge_rt because rt6i_ref count is not 1.
The root cause of all these is references related to the host route for
an address that is retained.
So, this patch deletes the host route every time the ifdown loop runs.
Since the host route is deleted and will be re-generated an up there is
no longer a need for the l3mdev fix up. On the 'admin up' side move
addrconf_permanent_addr into the NETDEV_UP event handling so that it
runs only once versus on UP and CHANGE events.
All of the current panics and warnings appear to be related to
addresses on the loopback device, but given the catastrophic nature when
a bug is triggered this patch takes the conservative approach and evicts
all host routes rather than trying to determine when it can be re-used
and when it can not. That can be a later optimizaton if desired.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 841645b5f2.
Ok, this puts the feature back. I've decided to apply David A.'s
bug fix and run with that rather than make everyone wait another
whole release for this feature.
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts the following three commits:
70af921db6799977d9aaf1705ec197
The feature was ill conceived, has terrible semantics, and has added
nothing but regressions to the already fragile ipv6 stack.
Fixes: f1705ec197 ("net: ipv6: Make address flushing on ifdown optional")
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts were two cases of simple overlapping changes,
nothing serious.
In the UDP case, we need to add a hlist_add_tail_rcu()
to linux/rculist.h, because we've moved UDP socket handling
away from using nulls lists.
Signed-off-by: David S. Miller <davem@davemloft.net>
Separated from previous patch for readability.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Struct ctl_table_header holds pointer to sysctl table which could be used
for freeing it after unregistration. IPv4 sysctls already use that.
Remove redundant NULL assignment: ndev allocated using kzalloc.
This also saves some bytes: sysctl table could be shorter than
DEVCONF_MAX+1 if some options are disable in config.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
f1705ec197 added the option to retain user configured addresses on an
admin down. A comment to one of the later revisions suggested using the
IFA_F_PERMANENT flag rather than adding a user_managed boolean to the
ifaddr struct. A side effect of this change is that link local and
loopback addresses are also retained which is not part of the objective
of f1705ec197. Add check to drop those addresses.
Fixes: f1705ec197 ("net: ipv6: Make address flushing on ifdown optional")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The original tokenized iid support implemented via f53adae4ea ("net: ipv6:
add tokenized interface identifier support") didn't allow for clearing a
device token as it was intended that this addressing mode was the only one
active for globally scoped IPv6 addresses. Later we relaxed that restriction
via 617fe29d45 ("net: ipv6: only invalidate previously tokenized addresses"),
and we should also allow for clearing tokens as there's no good reason why
it shouldn't be allowed.
Fixes: 617fe29d45 ("net: ipv6: only invalidate previously tokenized addresses")
Reported-by: Robin H. Johnson <robbat2@gentoo.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
ifupdown2 found a kernel bug with IPv6 routes and movement from the main
table to the VRF table. Sequence of events:
Create the interface and add addresses:
ip link add dev eth4.105 link eth4 type vlan id 105
ip addr add dev eth4.105 8.105.105.10/24
ip -6 addr add dev eth4.105 2008:105:105::10/64
At this point IPv6 has inserted a prefix route in the main table even
though the interface is 'down'. From there the VRF device is created:
ip link add dev vrf105 type vrf table 105
ip addr add dev vrf105 9.9.105.10/32
ip -6 addr add dev vrf105 2000:9:105::10/128
ip link set vrf105 up
Then the interface is enslaved, while still in the 'down' state:
ip link set dev eth4.105 master vrf105
Since the device is down the VRF driver cycling the device does not
send the NETDEV_UP and NETDEV_DOWN but rather the NETDEV_CHANGE event
which does not flush the routes inserted prior.
When the link is brought up
ip link set dev eth4.105 up
the prefix route is added in the VRF table, but does not remove
the route from the main table.
Fix by handling the NETDEV_CHANGEUPPER event similar what was implemented
for IPv4 in 7f49e7a38b ("net: Flush local routes when device changes vrf
association")
Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds macro NETCONFA_ALL to represent all type of netconf
attributes for IPv4 and IPv6.
Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrew and Ying Huang's test robot both reported usage count problems that
trace back to the 'keep address on ifdown' patch.
>From Andrew:
We execute CRIU test on linux-next. On the current linux-next kernel
they hangs on creating a network namespace.
The kernel log contains many massages like this:
[ 1036.122108] unregister_netdevice: waiting for lo to become free.
Usage count = 2
[ 1046.165156] unregister_netdevice: waiting for lo to become free.
Usage count = 2
[ 1056.210287] unregister_netdevice: waiting for lo to become free.
Usage count = 2
I tried to revert this patch and the bug disappeared.
Here is a set of commands to reproduce this bug:
[root@linux-next-test linux-next]# uname -a
Linux linux-next-test 4.5.0-rc6-next-20160301+ #3 SMP Wed Mar 2
17:32:18 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
[root@linux-next-test ~]# unshare -n
[root@linux-next-test ~]# ip link set up dev lo
[root@linux-next-test ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
group default qlen 1
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
[root@linux-next-test ~]# logout
[root@linux-next-test ~]# unshare -n
-----
The problem is a change made to RTM_DELADDR case in __ipv6_ifa_notify that
was added in an early version of the offending patch and is no longer
needed.
Fixes: f1705ec197 ("net: ipv6: Make address flushing on ifdown optional")
Cc: Andrey Wagin <avagin@gmail.com>
Cc: Ying Huang <ying.huang@linux.intel.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Tested-by: Jeremiah Mahler <jmmahler@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit f1705ec197 allows IPv6 addresses to be retained on a link down.
The address can have a cached host route which can point to the wrong
FIB table if the L3 enslavement is changed (e.g., route can point to local
table instead of VRF table if device is added to an L3 domain).
On link up check the table of the cached host route against the FIB
table associated with the device and correct if needed.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, all ipv6 addresses are flushed when the interface is configured
down, including global, static addresses:
$ ip -6 addr show dev eth1
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 state UP qlen 1000
inet6 2100:1::2/120 scope global
valid_lft forever preferred_lft forever
inet6 fe80::e0:f9ff:fe79:34bd/64 scope link
valid_lft forever preferred_lft forever
$ ip link set dev eth1 down
$ ip -6 addr show dev eth1
<< nothing; all addresses have been flushed>>
Add a new sysctl to make this behavior optional. The new setting defaults to
flush all addresses to maintain backwards compatibility. When the set global
addresses with no expire times are not flushed on an admin down. The sysctl
is per-interface or system-wide for all interfaces
$ sysctl -w net.ipv6.conf.eth1.keep_addr_on_down=1
or
$ sysctl -w net.ipv6.conf.all.keep_addr_on_down=1
Will keep addresses on eth1 on an admin down.
$ ip -6 addr show dev eth1
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 state UP qlen 1000
inet6 2100:1::2/120 scope global
valid_lft forever preferred_lft forever
inet6 fe80::e0:f9ff:fe79:34bd/64 scope link
valid_lft forever preferred_lft forever
$ ip link set dev eth1 down
$ ip -6 addr show dev eth1
3: eth1: <BROADCAST,MULTICAST> mtu 1500 state DOWN qlen 1000
inet6 2100:1::2/120 scope global tentative
valid_lft forever preferred_lft forever
inet6 fe80::e0:f9ff:fe79:34bd/64 scope link tentative
valid_lft forever preferred_lft forever
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/phy/bcm7xxx.c
drivers/net/phy/marvell.c
drivers/net/vxlan.c
All three conflicts were cases of simple overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
An error response from a RTM_GETNETCONF request can return the positive
error value EINVAL in the struct nlmsgerr that can mislead userspace.
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In certain 802.11 wireless deployments, there will be NA proxies
that use knowledge of the network to correctly answer requests.
To prevent unsolicitd advertisements on the shared medium from
being a problem, on such deployments wireless needs to drop them.
Enable this by providing an option called "drop_unsolicited_na".
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to solve a problem with 802.11, the so-called hole-196 attack,
add an option (sysctl) called "drop_unicast_in_l2_multicast" which, if
enabled, causes the stack to drop IPv6 unicast packets encapsulated in
link-layer multi- or broadcast frames. Such frames can (as an attack)
be created by any member of the same wireless network and transmitted
as valid encrypted frames since the symmetric key for broadcast frames
is shared between all stations.
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A rcu stall with the following backtrace was seen on a system with
forwarding, optimistic_dad and use_optimistic set. To reproduce,
set these flags and allow ipv6 autoconf.
This occurs because the device write_lock is acquired while already
holding the read_lock. Back trace below -
INFO: rcu_preempt self-detected stall on CPU { 1} (t=2100 jiffies
g=3992 c=3991 q=4471)
<6> Task dump for CPU 1:
<2> kworker/1:0 R running task 12168 15 2 0x00000002
<2> Workqueue: ipv6_addrconf addrconf_dad_work
<6> Call trace:
<2> [<ffffffc000084da8>] el1_irq+0x68/0xdc
<2> [<ffffffc000cc4e0c>] _raw_write_lock_bh+0x20/0x30
<2> [<ffffffc000bc5dd8>] __ipv6_dev_ac_inc+0x64/0x1b4
<2> [<ffffffc000bcbd2c>] addrconf_join_anycast+0x9c/0xc4
<2> [<ffffffc000bcf9f0>] __ipv6_ifa_notify+0x160/0x29c
<2> [<ffffffc000bcfb7c>] ipv6_ifa_notify+0x50/0x70
<2> [<ffffffc000bd035c>] addrconf_dad_work+0x314/0x334
<2> [<ffffffc0000b64c8>] process_one_work+0x244/0x3fc
<2> [<ffffffc0000b7324>] worker_thread+0x2f8/0x418
<2> [<ffffffc0000bb40c>] kthread+0xe0/0xec
v2: do addrconf_dad_kick inside read lock and then acquire write
lock for ipv6_ifa_notify as suggested by Eric
Fixes: 7fd2561e4e ("net: ipv6: Add a sysctl to make optimistic
addresses useful candidates")
Cc: Eric Dumazet <edumazet@google.com>
Cc: Erik Kline <ek@google.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The userspace needs to know why is the address being removed so that it can
perhaps obtain a new address.
Without the DADFAILED flag it's impossible to distinguish removal of a
temporary and tentative address due to DAD failure from other reasons (device
removed, manual address removal).
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
