icmp6_send() function is expensive on systems with a large number of
interfaces. Every time it’s called, it has to verify that the source
address does not correspond to an existing anycast address by looping
through every device and every anycast address on the device. This can
result in significant delays for a CPU when there are a large number of
neighbors and ND timers are frequently timing out and calling
neigh_invalidate().
Add anycast addresses to a global hashtable to allow quick searching for
matching anycast addresses. This is based on inet6_addr_lst in addrconf.c.
Signed-off-by: Jeff Barnhill <0xeffeff@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for IFA_RT_PRIORITY to ipv6 addresses.
If the metric is changed on an existing address then the new route
is inserted before removing the old one. Since the metric is one
of the route keys, the prefix route can not be atomically replaced.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
aca_idev has only 1 user - inet6_fill_ifacaddr - and it only
wants the device index which can be extracted from the fib6_info
nexthop.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Convert all code paths referencing a FIB entry from
rt6_info to fib6_info.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The address generation mode for IPv6 link-local can only be configured
by netlink messages. This patch adds the ability to change the address
generation mode via sysctl.
v1 -> v2
Removed the rtnl lock and switch to use RCU lock to iterate through
the netdev list.
v2 -> v3
Removed the addrgenmode variable from the idev structure and use the
systcl storage for the flag.
Simplifed the logic for sysctl handling by removing the supported
for all operation.
Added support for more types of tunnel interfaces for link-local
address generation.
Based the patches from net-next.
v3 -> v4
Removed unnecessary whitespace changes.
Signed-off-by: Felix Jia <felix.jia@alliedtelesis.co.nz>
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>
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>
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>
If a DAD conflict is detected, we want to retry privacy stable address
generation up to idgen_retries (= 3) times with a delay of idgen_delay
(= 1 second). Add the logic to addrconf_dad_failure.
By design, we don't clean up dad failed permanent addresses.
Cc: Erik Kline <ek@google.com>
Cc: Fernando Gont <fgont@si6networks.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: YOSHIFUJI Hideaki/吉藤英明 <hideaki.yoshifuji@miraclelinux.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces a possibility for userspace to set various (so far
two) modes of generating addresses. This is useful for example for
NetworkManager because it can set the mode to NONE and take care of link
local addresses itself. That allow it to have the interface up,
monitoring carrier but still don't have any addresses on it.
One more use-case by Dan Williams:
<quote>
WWAN devices often have their LL address provided by the firmware of the
device, which sometimes refuses to respond to incorrect LL addresses
when doing DHCPv6 or IPv6 ND. The kernel cannot generate the correct LL
address for two reasons:
1) WWAN pseudo-ethernet interfaces often construct a fake MAC address,
or read a meaningless MAC address from the firmware. Thus the EUI64 and
the IPv6LL address the kernel assigns will be wrong. The real LL
address is often retrieved from the firmware with AT or proprietary
commands.
2) WWAN PPP interfaces receive their LL address from IPV6CP, not from
kernel assignments. Only after IPV6CP has completed do we know the LL
address of the PPP interface and its peer. But the kernel has already
assigned an incorrect LL address to the interface.
So being able to suppress the kernel LL address generation and assign
the one retrieved from the firmware is less complicated and more robust.
</quote>
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
addrconf_join_solict and addrconf_join_anycast may cause actions which
need rtnl locked, especially on first address creation.
A new DAD state is introduced which defers processing of the initial
DAD processing into a workqueue.
To get rtnl lock we need to push the code paths which depend on those
calls up to workqueues, specifically addrconf_verify and the DAD
processing.
(v2)
addrconf_dad_failure needs to be queued up to the workqueue, too. This
patch introduces a new DAD state and stop the DAD processing in the
workqueue (this is because of the possible ipv6_del_addr processing
which removes the solicited multicast address from the device).
addrconf_verify_lock is removed, too. After the transition it is not
needed any more.
As we are not processing in bottom half anymore we need to be a bit more
careful about disabling bottom half out when we lock spin_locks which are also
used in bh.
Relevant backtrace:
[ 541.030090] RTNL: assertion failed at net/core/dev.c (4496)
[ 541.031143] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 3.10.33-1-amd64-vyatta #1
[ 541.031145] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[ 541.031146] ffffffff8148a9f0 000000000000002f ffffffff813c98c1 ffff88007c4451f8
[ 541.031148] 0000000000000000 0000000000000000 ffffffff813d3540 ffff88007fc03d18
[ 541.031150] 0000880000000006 ffff88007c445000 ffffffffa0194160 0000000000000000
[ 541.031152] Call Trace:
[ 541.031153] <IRQ> [<ffffffff8148a9f0>] ? dump_stack+0xd/0x17
[ 541.031180] [<ffffffff813c98c1>] ? __dev_set_promiscuity+0x101/0x180
[ 541.031183] [<ffffffff813d3540>] ? __hw_addr_create_ex+0x60/0xc0
[ 541.031185] [<ffffffff813cfe1a>] ? __dev_set_rx_mode+0xaa/0xc0
[ 541.031189] [<ffffffff813d3a81>] ? __dev_mc_add+0x61/0x90
[ 541.031198] [<ffffffffa01dcf9c>] ? igmp6_group_added+0xfc/0x1a0 [ipv6]
[ 541.031208] [<ffffffff8111237b>] ? kmem_cache_alloc+0xcb/0xd0
[ 541.031212] [<ffffffffa01ddcd7>] ? ipv6_dev_mc_inc+0x267/0x300 [ipv6]
[ 541.031216] [<ffffffffa01c2fae>] ? addrconf_join_solict+0x2e/0x40 [ipv6]
[ 541.031219] [<ffffffffa01ba2e9>] ? ipv6_dev_ac_inc+0x159/0x1f0 [ipv6]
[ 541.031223] [<ffffffffa01c0772>] ? addrconf_join_anycast+0x92/0xa0 [ipv6]
[ 541.031226] [<ffffffffa01c311e>] ? __ipv6_ifa_notify+0x11e/0x1e0 [ipv6]
[ 541.031229] [<ffffffffa01c3213>] ? ipv6_ifa_notify+0x33/0x50 [ipv6]
[ 541.031233] [<ffffffffa01c36c8>] ? addrconf_dad_completed+0x28/0x100 [ipv6]
[ 541.031241] [<ffffffff81075c1d>] ? task_cputime+0x2d/0x50
[ 541.031244] [<ffffffffa01c38d6>] ? addrconf_dad_timer+0x136/0x150 [ipv6]
[ 541.031247] [<ffffffffa01c37a0>] ? addrconf_dad_completed+0x100/0x100 [ipv6]
[ 541.031255] [<ffffffff8105313a>] ? call_timer_fn.isra.22+0x2a/0x90
[ 541.031258] [<ffffffffa01c37a0>] ? addrconf_dad_completed+0x100/0x100 [ipv6]
Hunks and backtrace stolen from a patch by Stephen Hemminger.
Reported-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
net/ipv4/tcp_metrics.c
Overlapping changes between the "don't create two tcp metrics objects
with the same key" race fix in net and the addition of the destination
address in the lookup key in net-next.
Minor overlapping changes in bnx2x driver.
Signed-off-by: David S. Miller <davem@davemloft.net>
In commit 1ec047eb47 ("ipv6: introduce per-interface counter for
dad-completed ipv6 addresses") I build the detection of the first
operational link-local address much to complex. Additionally this code
now has a race condition.
Replace it with a much simpler variant, which just scans the address
list when duplicate address detection completes, to check if this is
the first valid link local address and send RS and MLD reports then.
Fixes: 1ec047eb47 ("ipv6: introduce per-interface counter for dad-completed ipv6 addresses")
Reported-by: Jiri Pirko <jiri@resnulli.us>
Cc: Flavio Leitner <fbl@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Flavio Leitner <fbl@redhat.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no more space in u8 ifa_flags. So do what davem suffested and
add another netlink attr called IFA_FLAGS for carry more flags.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Thomas Haller <thaller@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The code for privacy extentions is very mature, and making it
configurable only gives marginal memory/code savings in exchange
for obfuscation and hard to read code via CPP ifdef'ery.
Signed-off-by: David S. Miller <davem@davemloft.net>
i) RFC3810, 9.2. Query Interval [QI] says:
The Query Interval variable denotes the interval between General
Queries sent by the Querier. Default value: 125 seconds. [...]
ii) RFC3810, 9.3. Query Response Interval [QRI] says:
The Maximum Response Delay used to calculate the Maximum Response
Code inserted into the periodic General Queries. Default value:
10000 (10 seconds) [...] The number of seconds represented by the
[Query Response Interval] must be less than the [Query Interval].
iii) RFC3810, 9.12. Older Version Querier Present Timeout [OVQPT] says:
The Older Version Querier Present Timeout is the time-out for
transitioning a host back to MLDv2 Host Compatibility Mode. When an
MLDv1 query is received, MLDv2 hosts set their Older Version Querier
Present Timer to [Older Version Querier Present Timeout].
This value MUST be ([Robustness Variable] times (the [Query Interval]
in the last Query received)) plus ([Query Response Interval]).
Hence, on *default* the timeout results in:
[RV] = 2, [QI] = 125sec, [QRI] = 10sec
[OVQPT] = [RV] * [QI] + [QRI] = 260sec
Having that said, we currently calculate [OVQPT] (here given as 'switchback'
variable) as ...
switchback = (idev->mc_qrv + 1) * max_delay
RFC3810, 9.12. says "the [Query Interval] in the last Query received". In
section "9.14. Configuring timers", it is said:
This section is meant to provide advice to network administrators on
how to tune these settings to their network. Ambitious router
implementations might tune these settings dynamically based upon
changing characteristics of the network. [...]
iv) RFC38010, 9.14.2. Query Interval:
The overall level of periodic MLD traffic is inversely proportional
to the Query Interval. A longer Query Interval results in a lower
overall level of MLD traffic. The value of the Query Interval MUST
be equal to or greater than the Maximum Response Delay used to
calculate the Maximum Response Code inserted in General Query
messages.
I assume that was why switchback is calculated as is (3 * max_delay), although
this setting seems to be meant for routers only to configure their [QI]
interval for non-default intervals. So usage here like this is clearly wrong.
Concluding, the current behaviour in IPv6's multicast code is not conform
to the RFC as switch back is calculated wrongly. That is, it has a too small
value, so MLDv2 hosts switch back again to MLDv2 way too early, i.e. ~30secs
instead of ~260secs on default.
Hence, introduce necessary helper functions and fix this up properly as it
should be.
Introduced in 06da92283 ("[IPV6]: Add MLDv2 support."). Credits to Hannes
Frederic Sowa who also had a hand in this as well. Also thanks to Hangbin Liu
who did initial testing.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: David Stevens <dlstevens@us.ibm.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
RFC3590/RFC3810 specifies we should resend MLD reports as soon as a
valid link-local address is available.
We now use the valid_ll_addr_cnt to check if it is necessary to resend
a new report.
Changes since Flavio Leitner's version:
a) adapt for valid_ll_addr_cnt
b) resend first reports directly in the path and just arm the timer for
mc_qrv-1 resends.
Reported-by: Flavio Leitner <fleitner@redhat.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David Stevens <dlstevens@us.ibm.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jeff Barnhill
David Ahern
Reshetova, Elena
Felix Jia
Erik Nordmark
Jiri Bohac
Maciej Żenczykowski
Hannes Frederic Sowa
Li RongQing
Sébastien Barré
Jiri Pirko
David S. Miller
Daniel Borkmann