Move the creation of struct ifa6_config up to callers of inet6_addr_add.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move config parameters for adding an ipv6 address to a struct. struct
names stem from inet6_rtm_newaddr which is the modern handler for
adding an address.
Start the conversion to ifa6_config with ipv6_add_addr. This is an argument
move only; no functional change intended. Mapping of variable changes:
addr --> cfg->pfx
peer_addr --> cfg->peer_pfx
pfxlen --> cfg->plen
flags --> cfg->ifa_flags
scope, valid_lft, prefered_lft have the same names within cfg
(with corrected spelling).
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Variants of proc_create{,_data} that directly take a struct seq_operations
and deal with network namespaces in ->open and ->release. All callers of
proc_create + seq_open_net converted over, and seq_{open,release}_net are
removed entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
The addrconf_ifdown() evaluates keep_addr_on_down state twice. There
is no need to do it.
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Ivan Vecera <cera@cera.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric noticed that __ipv6_ifa_notify is called under rcu_read_lock, so
the gfp argument to addrconf_prefix_route can not be GFP_KERNEL.
While scrubbing other calls I noticed addrconf_addr_gen has one
place with GFP_ATOMIC that can be GFP_KERNEL.
Fixes: acb54e3cba ("net/ipv6: Add gfp_flags to route add functions")
Reported-by: syzbot+2add39b05179b31f912f@syzkaller.appspotmail.com
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
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>
addrconf_dst_alloc now returns a fib6_info. Update the name
and its users to reflect the change.
Rename only; no functional change intended.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change the prefix for fib6_info struct elements from rt6i_ to fib6_.
rt6i_pcpu and rt6i_exception_bucket are left as is given that they
point to rt6_info entries.
Rename only; not functional change intended.
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>
Last step before flipping the data type for FIB entries:
- use fib6_info_alloc to create FIB entries in ip6_route_info_create
and addrconf_dst_alloc
- use fib6_info_release in place of dst_release, ip6_rt_put and
rt6_release
- remove the dst_hold before calling __ip6_ins_rt or ip6_del_rt
- when purging routes, drop per-cpu routes
- replace inc and dec of rt6i_ref with fib6_info_hold and fib6_info_release
- use rt->from since it points to the FIB entry
- drop references to exception bucket, fib6_metrics and per-cpu from
dst entries (those are relevant for fib entries only)
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Most FIB entries can be added using memory allocated with GFP_KERNEL.
Add gfp_flags to ip6_route_add and addrconf_dst_alloc. Code paths that
can be reached from the packet path (e.g., ndisc and autoconfig) or
atomic notifiers use GFP_ATOMIC; paths from user context (adding
addresses and routes) use GFP_KERNEL.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Continuing to wean FIB paths off of dst_entry, use a bool to hold
requests for certain dst settings. Add a helper to convert the
flags to DST flags when a FIB entry is converted to a dst_entry.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add expires to rt6_info for FIB entries, and add fib6 helpers to
manage it. Data path use of dst.expires remains.
The transition is fairly straightforward: when working with fib entries,
rt->dst.expires is just rt->expires, rt6_clean_expires is replaced with
fib6_clean_expires, rt6_set_expires becomes fib6_set_expires, and
rt6_check_expired becomes fib6_check_expired, where the fib6 versions
are added by this patch.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce fib6_nh structure and move nexthop related data from
rt6_info and rt6_info.dst to fib6_nh. References to dev, gateway or
lwtstate from a FIB lookup perspective are converted to use fib6_nh;
datapath references to dst version are left as is.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The RTN_ type for IPv6 FIB entries is currently embedded in rt6i_flags
and dst.error. Since dst is going to be removed, it can no longer be
relied on for FIB dumps so save the route type as fib6_type.
fc_type is set in current users based on the algorithm in rt6_fill_node:
- rt6i_flags contains RTF_LOCAL: fc_type = RTN_LOCAL
- rt6i_flags contains RTF_ANYCAST: fc_type = RTN_ANYCAST
- else fc_type = RTN_UNICAST
Similarly, fib6_type is set in the rt6_info templates based on the
RTF_REJECT section of rt6_fill_node converting dst.error to RTN type.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass network namespace reference into route add, delete and get
functions.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Send a netlink notification when userspace adds a manually configured
address if DAD is enabled and optimistic flag isn't set.
Moreover send RTM_DELADDR notifications for tentative addresses.
Some userspace applications (e.g. NetworkManager) are interested in
addr netlink events albeit the address is still in tentative state,
however events are not sent if DAD process is not completed.
If the address is added and immediately removed userspace listeners
are not notified. This behaviour can be easily reproduced by using
veth interfaces:
$ ip -b - <<EOF
> link add dev vm1 type veth peer name vm2
> link set dev vm1 up
> link set dev vm2 up
> addr add 2001:db8:a🅱️1:2:3:4/64 dev vm1
> addr del 2001:db8:a🅱️1:2:3:4/64 dev vm1
EOF
This patch reverts the behaviour introduced by the commit f784ad3d79
("ipv6: do not send RTM_DELADDR for tentative addresses")
Suggested-by: Thomas Haller <thaller@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove unnecessary check on update_lft variable in
addrconf_prefix_rcv_add_addr routine since it is always set to 0.
Moreover remove update_lft re-initialization to 0
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove local ADBG macro and use netdev_dbg/pr_debug
Miscellanea:
o Remove unnecessary debug message after allocation failure as there
already is a dump_stack() on the failure paths
o Leave the allocation failure message on snmp6_alloc_dev as there
is one code path that does not do a dump_stack()
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Prefer the direct use of octal for permissions.
Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace
and some typing.
Miscellanea:
o Whitespace neatening around these conversions.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lookup the L3 master device for the passed in device. Only consider
addresses on netdev's with the same master device. If the device is
not enslaved or is NULL, then the l3mdev is NULL which means only
devices not enslaved (ie, in the default domain) are considered.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6_chk_addr_and_flags determines if an address is a local address and
optionally if it is an address on a specific device. For example, it is
called by ip6_route_info_create to determine if a given gateway address
is a local address. The address check currently does not consider L3
domains and as a result does not allow a route to be added in one VRF
if the nexthop points to an address in a second VRF. e.g.,
$ ip route add 2001:db8:1::/64 vrf r2 via 2001:db8:102::23
Error: Invalid gateway address.
where 2001:db8:102::23 is an address on an interface in vrf r1.
ipv6_chk_addr_and_flags needs to allow callers to always pass in a device
with a separate argument to not limit the address to the specific device.
The device is used used to determine the L3 domain of interest.
To that end add an argument to skip the device check and update callers
to always pass a device where possible and use the new argument to mean
any address in the domain.
Update a handful of users of ipv6_chk_addr with a NULL dev argument. This
patch handles the change to these callers without adding the domain check.
ip6_validate_gw needs to handle 2 cases - one where the device is given
as part of the nexthop spec and the other where the device is resolved.
There is at least 1 VRF case where deferring the check to only after
the route lookup has resolved the device fails with an unintuitive error
"RTNETLINK answers: No route to host" as opposed to the preferred
"Error: Gateway can not be a local address." The 'no route to host'
error is because of the fallback to a full lookup. The check is done
twice to avoid this error.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
According to RFC 4429 (section 3.1), adding new IPv6 addresses as
optimistic addresses is acceptable, as long as the implementation
follows some rules:
* Optimistic DAD SHOULD only be used when the implementation is aware
that the address is based on a most likely unique interface
identifier (such as in [RFC2464]), generated randomly [RFC3041],
or by a well-distributed hash function [RFC3972] or assigned by
Dynamic Host Configuration Protocol for IPv6 (DHCPv6) [RFC3315].
Optimistic DAD SHOULD NOT be used for manually entered
addresses.
Thus, it seems reasonable to allow userspace to set the optimistic flag
when adding new addresses.
We must not let userspace set NODAD + OPTIMISTIC, since if the kernel is
not performing DAD we would never clear the optimistic flag. We must
also ignore userspace's request to add OPTIMISTIC flag to addresses that
have already completed DAD (addresses that don't have the TENTATIVE
flag, or that have the DADFAILED flag).
Then we also need to clear the OPTIMISTIC flag on permanent addresses
when DAD fails. Otherwise, IFA_F_OPTIMISTIC addresses added by userspace
can still be used after DAD has failed, because in
ipv6_chk_addr_and_flags(), IFA_F_OPTIMISTIC overrides IFA_F_TENTATIVE.
Setting IFA_F_OPTIMISTIC from userspace is conditional on
CONFIG_IPV6_OPTIMISTIC_DAD and the optimistic_dad sysctl.
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
These pernet_operations create and destroy /proc entries
and safely may be converted and safely may be mark as async.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
These pernet_operations (un)register sysctl, which
are not touched by anybody else.
So, it's safe to make them async.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unsolicited IPv6 neighbor advertisements should be sent after DAD
completes. Update ndisc_send_unsol_na to skip tentative, non-optimistic
addresses and have those sent by addrconf_dad_completed after DAD.
Fixes: 4a6e3c5def ("net: ipv6: send unsolicited NA on admin up")
Reported-by: Vivek Venkatraman <vivek@cumulusnetworks.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
/proc has been ignoring struct file_operations::owner field for 10 years.
Specifically, it started with commit 786d7e1612
("Fix rmmod/read/write races in /proc entries"). Notice the chunk where
inode->i_fop is initialized with proxy struct file_operations for
regular files:
- if (de->proc_fops)
- inode->i_fop = de->proc_fops;
+ if (de->proc_fops) {
+ if (S_ISREG(inode->i_mode))
+ inode->i_fop = &proc_reg_file_ops;
+ else
+ inode->i_fop = de->proc_fops;
+ }
VFS stopped pinning module at this point.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to IPv4, when the carrier of a netdev changes we should toggle
the 'linkdown' flag on all the nexthops using it as their nexthop
device.
This will later allow us to test for the presence of this flag during
route lookup and dump.
Up until commit 4832c30d54 ("net: ipv6: put host and anycast routes on
device with address") host and anycast routes used the loopback netdev
as their nexthop device and thus were not marked with the 'linkdown'
flag. The patch preserves this behavior and allows one to ping the local
address even when the nexthop device does not have a carrier and the
'ignore_routes_with_linkdown' sysctl is set.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To make IPv6 more in line with IPv4 we need to be able to respond
differently to different netdev events. For example, when a netdev is
unregistered all the routes using it as their nexthop device should be
flushed, whereas when the netdev's carrier changes only the 'linkdown'
flag should be toggled.
Currently, this is not possible, as the function that traverses the
routing tables is not aware of the triggering event.
Propagate the triggering event down, so that it could be used in later
patches.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previous patch marked nexthops with the 'dead' and 'linkdown' flags.
Clear these flags when the netdev comes back up.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
convert remaining users of rtnl_register to rtnl_register_module
and un-export rtnl_register.
Requested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This removes __rtnl_register and switches callers to either
rtnl_register or rtnl_register_module.
Also, rtnl_register() will now print an error if memory allocation
failed rather than panic the kernel.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
With commits 35e015e1f5 and a2d3f3e338, the global 'accept_dad' flag
is also taken into account (default value is 1). If either global or
per-interface flag is non-zero, DAD will be enabled on a given interface.
This is not backward compatible: before those patches, the user could
disable DAD just by setting the per-interface flag to 0. Now, the
user instead needs to set both flags to 0 to actually disable DAD.
Restore the previous behaviour by setting the default for the global
'accept_dad' flag to 0. This way, DAD is still enabled by default,
as per-interface flags are set to 1 on device creation, but setting
them to 0 is enough to disable DAD on a given interface.
- Before 35e015e1f57a7 and a2d3f3e338:
global per-interface DAD enabled
[default] 1 1 yes
X 0 no
X 1 yes
- After 35e015e1f5 and a2d3f3e338:
global per-interface DAD enabled
[default] 1 1 yes
0 0 no
0 1 yes
1 0 yes
- After this fix:
global per-interface DAD enabled
1 1 yes
0 0 no
[default] 0 1 yes
1 0 yes
Fixes: 35e015e1f5 ("ipv6: fix net.ipv6.conf.all interface DAD handlers")
Fixes: a2d3f3e338 ("ipv6: fix net.ipv6.conf.all.accept_dad behaviour for real")
CC: Stefano Brivio <sbrivio@redhat.com>
CC: Matteo Croce <mcroce@redhat.com>
CC: Erik Kline <ek@google.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a per-device sysctl to specify the default traffic class to use for
kernel originated IPv6 Neighbour Discovery packets.
Currently this includes:
- Router Solicitation (ICMPv6 type 133)
ndisc_send_rs() -> ndisc_send_skb() -> ip6_nd_hdr()
- Neighbour Solicitation (ICMPv6 type 135)
ndisc_send_ns() -> ndisc_send_skb() -> ip6_nd_hdr()
- Neighbour Advertisement (ICMPv6 type 136)
ndisc_send_na() -> ndisc_send_skb() -> ip6_nd_hdr()
- Redirect (ICMPv6 type 137)
ndisc_send_redirect() -> ndisc_send_skb() -> ip6_nd_hdr()
and if the kernel ever gets around to generating RA's,
it would presumably also include:
- Router Advertisement (ICMPv6 type 134)
(radvd daemon could pick up on the kernel setting and use it)
Interface drivers may examine the Traffic Class value and translate
the DiffServ Code Point into a link-layer appropriate traffic
prioritization scheme. An example of mapping IETF DSCP values to
IEEE 802.11 User Priority values can be found here:
https://tools.ietf.org/html/draft-ietf-tsvwg-ieee-802-11
The expected primary use case is to properly prioritize ND over wifi.
Testing:
jzem22:~# cat /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
0
jzem22:~# echo -1 > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
-bash: echo: write error: Invalid argument
jzem22:~# echo 256 > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
-bash: echo: write error: Invalid argument
jzem22:~# echo 0 > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
jzem22:~# echo 255 > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
jzem22:~# cat /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
255
jzem22:~# echo 34 > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
jzem22:~# cat /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
34
jzem22:~# echo $[0xDC] > /proc/sys/net/ipv6/conf/eth0/ndisc_tclass
jzem22:~# tcpdump -v -i eth0 icmp6 and src host jzem22.pgc and dst host fe80::1
tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 262144 bytes
IP6 (class 0xdc, hlim 255, next-header ICMPv6 (58) payload length: 24)
jzem22.pgc > fe80::1: [icmp6 sum ok] ICMP6, neighbor advertisement,
length 24, tgt is jzem22.pgc, Flags [solicited]
(based on original change written by Erik Kline, with minor changes)
v2: fix 'suspicious rcu_dereference_check() usage'
by explicitly grabbing the rcu_read_lock.
Cc: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Erik Kline <ek@google.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IN6_ADDR_HSIZE is private to addrconf.c, move it here to avoid
confusion.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Smooth Cong Wang's bug fix into 'net-next'. Basically put
the bulk of the tcf_block_put() logic from 'net' into
tcf_block_put_ext(), but after the offload unbind.
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch updates the error messages displayed in kernel log to include
hwaddress of the source machine that caused ipv6 duplicate address
detection failures.
Examples:
a) When we receive a NA packet from another machine advertising our
address:
ICMPv6: NA: 34🆎cd:56:11:e8 advertised our address 2001:db8:: on eth0!
b) When we detect DAD failure during address assignment to an interface:
IPv6: eth0: IPv6 duplicate address 2001:db8:: used by 34🆎cd:56:11:e8
detected!
v2:
Changed %pI6 to %pI6c in ndisc_recv_na()
Chaged the v6 address in the commit message to 2001:db8::
Suggested-by: Igor Lubashev <ilubashe@akamai.com>
Signed-off-by: Vishwanath Pai <vpai@akamai.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rcu_read_lock() is enough here, no need to block BH.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Table is really RCU protected, no need to block BH
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rcu_read_lock() is enough here, no need to block BH.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
rcu_read_lock() is enough here, as inet6_ifa_finish_destroy()
uses kfree_rcu()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Bring IPv6 in par with IPv4 :
- Use net_hash_mix() to spread addresses a bit more.
- Use 256 slots hash table instead of 16
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6_add_addr_hash() can compute the hash value outside of
locked section and pass it to ipv6_chk_same_addr().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6_chk_same_addr() is only used by ipv6_add_addr_hash(),
so moving it avoids a forward declaration.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add extack to in_validator_info and in6_validator_info. Update the one
user of each, ipvlan, to return an error message for failures.
Only manual configuration of an address is plumbed in the IPv6 code path.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet6addr_validator chain was added by commit 3ad7d2468f ("Ipvlan
should return an error when an address is already in use") to allow
address validation before changes are committed and to be able to
fail the address change with an error back to the user. The address
validation is not done for addresses received from router
advertisements.
Handling RAs in softirq context is the only reason for the notifier
chain to be atomic versus blocking. Since the only current user, ipvlan,
of the validator chain ignores softirq context, the notifier can be made
blocking and simply not invoked for softirq path.
The blocking option is needed by spectrum for example to validate
resources for an adding an address to an interface.
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6_add_addr is called in process context with rtnl lock held
(e.g., manual config of an address) or during softirq processing
(e.g., autoconf and address from a router advertisement).
Currently, ipv6_add_addr calls rcu_read_lock_bh shortly after entry
and does not call unlock until exit, minus the call around the address
validator notifier. Similarly, addrconf_hash_lock is taken after the
validator notifier and held until exit. This forces the allocation of
inet6_ifaddr to always be atomic.
Refactor ipv6_add_addr as follows:
1. add an input boolean to discriminate the call path (process context
or softirq). This new flag controls whether the alloc can be done
with GFP_KERNEL or GFP_ATOMIC.
2. Move the rcu_read_lock_bh and unlock calls only around functions that
do rcu updates.
3. Remove the in6_dev_hold and put added by 3ad7d2468f ("Ipvlan should
return an error when an address is already in use."). This was done
presumably because rcu_read_unlock_bh needs to be called before calling
the validator. Since rcu_read_lock is not needed before the validator
runs revert the hold and put added by 3ad7d2468f and only do the
hold when setting ifp->idev.
4. move duplicate address check and insertion of new address in the global
address hash into a helper. The helper is called after an ifa is
allocated and filled in.
This allows the ifa for manually configured addresses to be done with
GFP_KERNEL and reduces the overall amount of time with rcu_read_lock held
and hash table spinlock held.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to the previous patch, use the device lookup functions
that bump device refcount and flag this as DOIT_UNLOCKED to avoid
rtnl mutex.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of relying on rtnl mutex bump device reference count.
After this change, values reported can change in parallel, but thats not
much different from current state, as anyone can change the settings
right after rtnl_unlock (and before userspace processed reply).
While at it, switch to GFP_KERNEL allocation.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
By extending the rcu section a bit, we can avoid these
very expensive in6_ifa_put()/in6_ifa_hold() calls
done in __ipv6_dev_get_saddr() and ipv6_dev_get_saddr()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Callers hold rcu_read_lock(), so we do not need
the rcu_read_lock()/rcu_read_unlock() pair.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet6_ifa_finish_destroy() already uses kfree_rcu() to free
inet6_ifaddr structs.
We need to use proper list additions/deletions in order
to allow readers to use RCU instead of idev->lock rwlock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 35e015e1f5 ("ipv6: fix net.ipv6.conf.all interface DAD handlers")
was intended to affect accept_dad flag handling in such a way that
DAD operation and mode on a given interface would be selected
according to the maximum value of conf/{all,interface}/accept_dad.
However, addrconf_dad_begin() checks for particular cases in which we
need to skip DAD, and this check was modified in the wrong way.
Namely, it was modified so that, if the accept_dad flag is 0 for the
given interface *or* for all interfaces, DAD would be skipped.
We have instead to skip DAD if accept_dad is 0 for the given interface
*and* for all interfaces.
Fixes: 35e015e1f5 ("ipv6: fix net.ipv6.conf.all interface DAD handlers")
Acked-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Reported-by: Erik Kline <ek@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With all the preparation work before, we are now ready to replace rwlock
with rcu and spinlock in fib6_table.
That means now all fib6_node in fib6_table are protected by rcu. And
when freeing fib6_node, call_rcu() is used to wait for the rcu grace
period before releasing the memory.
When accessing fib6_node, corresponding rcu APIs need to be used.
And all previous sessions protected by the write lock will now be
protected by the spin lock per table.
All previous sessions protected by read lock will now be protected by
rcu_read_lock().
A couple of things to note here:
1. As part of the work of replacing rwlock with rcu, the linked list of
fn->leaf now has to be rcu protected as well. So both fn->leaf and
rt->dst.rt6_next are now __rcu tagged and corresponding rcu APIs are
used when manipulating them.
2. For fn->rr_ptr, first of all, it also needs to be rcu protected now
and is tagged with __rcu and rcu APIs are used in corresponding places.
Secondly, fn->rr_ptr is changed in rt6_select() which is a reader
thread. This makes the issue a bit complicated. We think a valid
solution for it is to let rt6_select() grab the tb6_lock if it decides
to change it. As it is not in the normal operation and only happens when
there is no valid neighbor cache for the route, we think the performance
impact should be low.
3. fib6_walk_continue() has to be called with tb6_lock held even in the
route dumping related functions, e.g. inet6_dump_fib(),
fib6_tables_dump() and ipv6_route_seq_ops. It is because
fib6_walk_continue() makes modifications to the walker structure, and so
are fib6_repair_tree() and fib6_del_route(). In order to do proper
syncing between them, we need to let fib6_walk_continue() hold the lock.
We may be able to do further improvement on the way we do the tree walk
to get rid of the need for holding the spin lock. But not for now.
4. When fib6_del_route() removes a route from the tree, we no longer
mark rt->dst.rt6_next to NULL to make simultaneous reader be able to
further traverse the list with rcu. However, rt->dst.rt6_next is only
valid within this same rcu period. No one should access it later.
5. All the operation of atomic_inc(rt->rt6i_ref) is changed to be
performed before we publish this route (either by linking it to fn->leaf
or insert it in the list pointed by fn->leaf) just to be safe because as
soon as we publish the route, some read thread will be able to access it.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With rwlock, it is safe to call dst_hold() in the read thread because
read thread is guaranteed to be separated from write thread.
However, after we replace rwlock with rcu, it is no longer safe to use
dst_hold(). A dst might already have been deleted but is waiting for the
rcu grace period to pass before freeing the memory when a read thread is
trying to do dst_hold(). This could potentially cause double free issue.
So this commit replaces all dst_hold() with dst_hold_safe() in all read
thread to avoid this double free issue.
And in order to make the code more compact, a new function ip6_hold_safe()
is introduced. It calls dst_hold_safe() first, and if that fails, it will
either fall back to hold and return net->ipv6.ip6_null_entry or set rt to
NULL according to the caller's need.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit makes use of the exception hash table implementation to
store dst caches created by pmtu discovery and ip redirect into the hash
table under the rt_info and no longer inserts these routes into fib6
tree.
This makes the fib6 tree only contain static configured routes and could
now be protected by rcu instead of a rw lock.
With this change, in the route lookup related functions, after finding
the rt6_info with the longest prefix, we also need to search for the
exception table before doing backtracking.
In the route delete function, if the route being deleted is not a dst
cache, deletion of this route also need to flush the whole hash table
under it. If it is a dst cache, then only delete the cached dst in the
hash table.
Note: for fib6_walk_continue() function, w->root now is always pointing
to a root node considering that fib6_prune_clones() is removed from the
code. So we add a WARN_ON() msg to make sure w->root always points to a
root node and also removed the update of w->root in fib6_repair_tree().
This is a prerequisite for later patch because we don't need to make
w->root as rcu protected when replacing rwlock with RCU.
Also, we remove all prune related variables as it is no longer used.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fib6_locate() is used to find the fib6_node according to the passed in
prefix address key. It currently tries to find the fib6_node with the
exact match of the passed in key. However, when we move cached routes
into the exception table, fib6_locate() will fail to find the fib6_node
for it as the cached routes will be stored in the exception table under
the fib6_node with the longest prefix match of the cache's dst addr key.
This commit adds a new parameter to let the caller specify if it needs
exact match or longest prefix match.
Right now, all callers still does exact match when calling
fib6_locate(). It will be changed in later commit where exception table
is hooked up to store cached routes.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The NS for DAD are sent on admin up as long as a valid qdisc is found.
A race condition exists by which these packets will not egress the
interface if the operational state of the lower device is not yet up.
The solution is to delay DAD until the link is operationally up
according to RFC2863. Rather than only doing this, follow the existing
code checks by deferring IPv6 device initialization altogether. The fix
allows DAD on devices like tunnels that are controlled by userspace
control plane. The fix has no impact on regular deployments, but means
that there is no IPv6 connectivity until the port has been opened in
the case of port-based network access control, which should be
desirable.
Signed-off-by: Mike Manning <mmanning@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IS_ERR() already implies unlikely(), so it can be omitted.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, writing into
net.ipv6.conf.all.{accept_dad,use_optimistic,optimistic_dad} has no effect.
Fix handling of these flags by:
- using the maximum of global and per-interface values for the
accept_dad flag. That is, if at least one of the two values is
non-zero, enable DAD on the interface. If at least one value is
set to 2, enable DAD and disable IPv6 operation on the interface if
MAC-based link-local address was found
- using the logical OR of global and per-interface values for the
optimistic_dad flag. If at least one of them is set to one, optimistic
duplicate address detection (RFC 4429) is enabled on the interface
- using the logical OR of global and per-interface values for the
use_optimistic flag. If at least one of them is set to one,
optimistic addresses won't be marked as deprecated during source address
selection on the interface.
While at it, as we're modifying the prototype for ipv6_use_optimistic_addr(),
drop inline, and let the compiler decide.
Fixes: 7fd2561e4e ("net: ipv6: Add a sysctl to make optimistic addresses useful candidates")
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit f784ad3d79 ("ipv6: do not send RTM_DELADDR for tentative
addresses") incorrectly assumes that no RTM_NEWADDR are sent for
addresses in tentative state, as this does happen for the standard
IPv6 use-case of DAD failure, see the call to ipv6_ifa_notify() in
addconf_dad_stop(). So as a result of this change, no RTM_DELADDR is
sent after DAD failure for a link-local when strict DAD (accept_dad=2)
is configured, or on the next admin down in other cases. The absence
of this notification breaks backwards compatibility and causes problems
after DAD failure if this notification was being relied on. The
solution is to allow RTM_DELADDR to still be sent after DAD failure.
Fixes: f784ad3d79 ("ipv6: do not send RTM_DELADDR for tentative addresses")
Signed-off-by: Mike Manning <mmanning@brocade.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit c5cff8561d adds rcu grace period before freeing fib6_node. This
generates a new sparse warning on rt->rt6i_node related code:
net/ipv6/route.c:1394:30: error: incompatible types in comparison
expression (different address spaces)
./include/net/ip6_fib.h:187:14: error: incompatible types in comparison
expression (different address spaces)
This commit adds "__rcu" tag for rt6i_node and makes sure corresponding
rcu API is used for it.
After this fix, sparse no longer generates the above warning.
Fixes: c5cff8561d ("ipv6: add rcu grace period before freeing fib6_node")
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
One nagging difference between ipv4 and ipv6 is host routes for ipv6
addresses are installed using the loopback device or VRF / L3 Master
device. e.g.,
2001:db8:1::/120 dev veth0 proto kernel metric 256 pref medium
local 2001:db8:1::1 dev lo table local proto kernel metric 0 pref medium
Using the loopback device is convenient -- necessary for local tx, but
has some nasty side effects, most notably setting the 'lo' device down
causes all host routes for all local IPv6 address to be removed from the
FIB and completely breaks IPv6 networking across all interfaces.
This patch puts FIB entries for IPv6 routes against the device. This
simplifies the routes in the FIB, for example by making dst->dev and
rt6i_idev->dev the same (a future patch can look at removing the device
reference taken for rt6i_idev for FIB entries).
When copies are made on FIB lookups, the cloned route has dst->dev
set to loopback (or the L3 master device). This is needed for the
local Tx of packets to local addresses.
With fib entries allocated against the real network device, the addrconf
code that reinserts host routes on admin up of 'lo' is no longer needed.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This change allows us to later indicate to rtnetlink core that certain
doit functions should be called without acquiring rtnl_mutex.
This change should have no effect, we simply replace the last (now
unused) calcit argument with the new flag.
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When an interface is brought back up, the kernel tries to restore the
host routes tied to its permanent addresses.
However, if the host route was removed from the FIB, then we need to
reinsert it. This is done by releasing the current dst and allocating a
new, so as to not reuse a dst with obsolete values.
Since this function is called under RTNL and using the same explanation
from the previous patch, we can test if the route is in the FIB by
checking its node pointer instead of its reference count.
Tested using the following script and Andrey's reproducer mentioned
in commit 8048ced9be ("net: ipv6: regenerate host route if moved to gc
list") and linked below:
$ ip link set dev lo up
$ ip link add dummy1 type dummy
$ ip -6 address add cafe::1/64 dev dummy1
$ ip link set dev lo down # cafe::1/128 is removed
$ ip link set dev dummy1 up
$ ip link set dev lo up
The host route is correctly regenerated.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Link: http://lkml.kernel.org/r/CAAeHK+zSe82vc5gCRgr_EoUwiALPnWVdWJBPwJZBpbxYz=kGJw@mail.gmail.com
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the loopback device is brought back up we need to check if the host
route attached to the address is still in the FIB and regenerate one in
case it's not.
Host routes using the loopback device are always inserted into and
removed from the FIB under RTNL (under which this function is called),
so we can test their node pointer instead of the reference count in
order to check if the route is in the FIB or not.
Tested using the following script from Nicolas mentioned in
commit a220445f9f ("ipv6: correctly add local routes when lo goes up"):
$ ip link add dummy1 type dummy
$ ip link set dummy1 up
$ ip link set lo down ; ip link set lo up
The host route is correctly regenerated.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.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>
Currently, when the link for $DEV is down, this command succeeds but the
address is removed immediately by DAD (1):
ip addr add 1111::12/64 dev $DEV valid_lft 3600 preferred_lft 1800
In the same situation, this will succeed and not remove the address (2):
ip addr add 1111::12/64 dev $DEV
ip addr change 1111::12/64 dev $DEV valid_lft 3600 preferred_lft 1800
The comment in addrconf_dad_begin() when !IF_READY makes it look like
this is the intended behavior, but doesn't explain why:
* If the device is not ready:
* - keep it tentative if it is a permanent address.
* - otherwise, kill it.
We clearly cannot prevent userspace from doing (2), but we can make (1)
work consistently with (2).
addrconf_dad_stop() is only called in two cases: if DAD failed, or to
skip DAD when the link is down. In that second case, the fix is to avoid
deleting the address, like we already do for permanent addresses.
Fixes: 3c21edbd11 ("[IPV6]: Defer IPv6 device initialization until the link becomes ready.")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The per netns loopback_dev->ip6_ptr is unregistered and set to
NULL when its mtu is set to smaller than IPV6_MIN_MTU, this
leads to that we could set rt->rt6i_idev NULL after a
rt6_uncached_list_flush_dev() and then crash after another
call.
In this case we should just bring its inet6_dev down, rather
than unregistering it, at least prior to commit 176c39af29
("netns: fix addrconf_ifdown kernel panic") we always
override the case for loopback.
Thanks a lot to Andrey for finding a reliable reproducer.
Fixes: 176c39af29 ("netns: fix addrconf_ifdown kernel panic")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Daniel Lezcano <dlezcano@fr.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Two entries being added at the same time to the IFLA
policy table, whilst parallel bug fixes to decnet
routing dst handling overlapping with the dst gc removal
in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar as ipv4, ipv6 path also needs to call dst_hold_safe() when
necessary to avoid double free issue on the dst.
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now when starting the dad work in addrconf_mod_dad_work, if the dad work
is idle and queued, it needs to hold ifa.
The problem is there's one gap in [1], during which if the pending dad work
is removed elsewhere. It will miss to hold ifa, but the dad word is still
idea and queue.
if (!delayed_work_pending(&ifp->dad_work))
in6_ifa_hold(ifp);
<--------------[1]
mod_delayed_work(addrconf_wq, &ifp->dad_work, delay);
An use-after-free issue can be caused by this.
Chen Wei found this issue when WARN_ON(!hlist_unhashed(&ifp->addr_lst)) in
net6_ifa_finish_destroy was hit because of it.
As Hannes' suggestion, this patch is to fix it by holding ifa first in
addrconf_mod_dad_work, then calling mod_delayed_work and putting ifa if
the dad_work is already in queue.
Note that this patch did not choose to fix it with:
if (!mod_delayed_work(delay))
in6_ifa_hold(ifp);
As with it, when delay == 0, dad_work would be scheduled immediately, all
addrconf_mod_dad_work(0) callings had to be moved under ifp->lock.
Reported-by: Wei Chen <weichen@redhat.com>
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ipvlan code already knows how to detect when a duplicate address is
about to be assigned to an ipvlan device. However, that failure is not
propogated outward and leads to a silent failure.
Introduce a validation step at ip address creation time and allow device
drivers to register to validate the incoming ip addresses. The ipvlan
code is the first consumer. If it detects an address in use, we can
return an error to the user before beginning to commit the new ifa in
the networking code.
This can be especially useful if it is necessary to provision many
ipvlans in containers. The provisioning software (or operator) can use
this to detect situations where an ip address is unexpectedly in use.
Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Every address gets added with TENTATIVE flag even for the addresses with
IFA_F_NODAD flag and dad-work is scheduled for them. During this DAD process
we realize it's an address with NODAD and complete the process without
sending any probe. However the TENTATIVE flags stays on the
address for sometime enough to cause misinterpretation when we receive a NS.
While processing NS, if the address has TENTATIVE flag, we mark it DADFAILED
and endup with an address that was originally configured as NODAD with
DADFAILED.
We can't avoid scheduling dad_work for addresses with NODAD but we can
avoid adding TENTATIVE flag to avoid this racy situation.
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For each netns (except init_net), we initialize its null entry
in 3 places:
1) The template itself, as we use kmemdup()
2) Code around dst_init_metrics() in ip6_route_net_init()
3) ip6_route_dev_notify(), which is supposed to initialize it after
loopback registers
Unfortunately the last one still happens in a wrong order because
we expect to initialize net->ipv6.ip6_null_entry->rt6i_idev to
net->loopback_dev's idev, thus we have to do that after we add
idev to loopback. However, this notifier has priority == 0 same as
ipv6_dev_notf, and ipv6_dev_notf is registered after
ip6_route_dev_notifier so it is called actually after
ip6_route_dev_notifier. This is similar to commit 2f460933f5
("ipv6: initialize route null entry in addrconf_init()") which
fixes init_net.
Fix it by picking a smaller priority for ip6_route_dev_notifier.
Also, we have to release the refcnt accordingly when unregistering
loopback_dev because device exit functions are called before subsys
exit functions.
Acked-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrey reported a crash on init_net.ipv6.ip6_null_entry->rt6i_idev
since it is always NULL.
This is clearly wrong, we have code to initialize it to loopback_dev,
unfortunately the order is still not correct.
loopback_dev is registered very early during boot, we lose a chance
to re-initialize it in notifier. addrconf_init() is called after
ip6_route_init(), which means we have no chance to correct it.
Fix it by moving this initialization explicitly after
ipv6_add_dev(init_net.loopback_dev) in addrconf_init().
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrey reported a warning triggered by the rcu code:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 5911 at lib/debugobjects.c:289
debug_print_object+0x175/0x210
ODEBUG: activate active (active state 1) object type: rcu_head hint:
(null)
Modules linked in:
CPU: 1 PID: 5911 Comm: a.out Not tainted 4.11.0-rc8+ #271
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:16
dump_stack+0x192/0x22d lib/dump_stack.c:52
__warn+0x19f/0x1e0 kernel/panic.c:549
warn_slowpath_fmt+0xe0/0x120 kernel/panic.c:564
debug_print_object+0x175/0x210 lib/debugobjects.c:286
debug_object_activate+0x574/0x7e0 lib/debugobjects.c:442
debug_rcu_head_queue kernel/rcu/rcu.h:75
__call_rcu.constprop.76+0xff/0x9c0 kernel/rcu/tree.c:3229
call_rcu_sched+0x12/0x20 kernel/rcu/tree.c:3288
rt6_rcu_free net/ipv6/ip6_fib.c:158
rt6_release+0x1ea/0x290 net/ipv6/ip6_fib.c:188
fib6_del_route net/ipv6/ip6_fib.c:1461
fib6_del+0xa42/0xdc0 net/ipv6/ip6_fib.c:1500
__ip6_del_rt+0x100/0x160 net/ipv6/route.c:2174
ip6_del_rt+0x140/0x1b0 net/ipv6/route.c:2187
__ipv6_ifa_notify+0x269/0x780 net/ipv6/addrconf.c:5520
addrconf_ifdown+0xe60/0x1a20 net/ipv6/addrconf.c:3672
...
Andrey's reproducer program runs in a very tight loop, calling
'unshare -n' and then spawning 2 sets of 14 threads running random ioctl
calls. The relevant networking sequence:
1. New network namespace created via unshare -n
- ip6tnl0 device is created in down state
2. address added to ip6tnl0
- equivalent to ip -6 addr add dev ip6tnl0 fd00::bb/1
- DAD is started on the address and when it completes the host
route is inserted into the FIB
3. ip6tnl0 is brought up
- the new fixup_permanent_addr function restarts DAD on the address
4. exit namespace
- teardown / cleanup sequence starts
- once in a blue moon, lo teardown appears to happen BEFORE teardown
of ip6tunl0
+ down on 'lo' removes the host route from the FIB since the dst->dev
for the route is loobback
+ host route added to rcu callback list
* rcu callback has not run yet, so rt is NOT on the gc list so it has
NOT been marked obsolete
5. in parallel to 4. worker_thread runs addrconf_dad_completed
- DAD on the address on ip6tnl0 completes
- calls ipv6_ifa_notify which inserts the host route
All of that happens very quickly. The result is that a host route that
has been deleted from the IPv6 FIB and added to the RCU list is re-inserted
into the FIB.
The exit namespace eventually gets to cleaning up ip6tnl0 which removes the
host route from the FIB again, calls the rcu function for cleanup -- and
triggers the double rcu trace.
The root cause is duplicate DAD on the address -- steps 2 and 3. Arguably,
DAD should not be started in step 2. The interface is in the down state,
so it can not really send out requests for the address which makes starting
DAD pointless.
Since the second DAD was introduced by a recent change, seems appropriate
to use it for the Fixes tag and have the fixup function only start DAD for
addresses in the PREDAD state which occurs in addrconf_ifdown if the
address is retained.
Big thanks to Andrey for isolating a reliable reproducer for this problem.
Fixes: f1705ec197 ("net: ipv6: Make address flushing on ifdown optional")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Taking down the loopback device wreaks havoc on IPv6 routing. By
extension, taking down a VRF device wreaks havoc on its table.
Dmitry and Andrey both reported heap out-of-bounds reports in the IPv6
FIB code while running syzkaller fuzzer. The root cause is a dead dst
that is on the garbage list gets reinserted into the IPv6 FIB. While on
the gc (or perhaps when it gets added to the gc list) the dst->next is
set to an IPv4 dst. A subsequent walk of the ipv6 tables causes the
out-of-bounds access.
Andrey's reproducer was the key to getting to the bottom of this.
With IPv6, host routes for an address have the dst->dev set to the
loopback device. When the 'lo' device is taken down, rt6_ifdown initiates
a walk of the fib evicting routes with the 'lo' device which means all
host routes are removed. That process moves the dst which is attached to
an inet6_ifaddr to the gc list and marks it as dead.
The recent change to keep global IPv6 addresses added a new function,
fixup_permanent_addr, that is called on admin up. That function restarts
dad for an inet6_ifaddr and when it completes the host route attached
to it is inserted into the fib. Since the route was marked dead and
moved to the gc list, re-inserting the route causes the reported
out-of-bounds accesses. If the device with the address is taken down
or the address is removed, the WARN_ON in fib6_del is triggered.
All of those faults are fixed by regenerating the host route if the
existing one has been moved to the gc list, something that can be
determined by checking if the rt6i_ref counter is 0.
Fixes: f1705ec197 ("net: ipv6: Make address flushing on ifdown optional")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add netlink_ext_ack arg to rtnl_doit_func. Pass extack arg to nlmsg_parse
for doit functions that call it directly.
This is the first step to using extended error reporting in rtnetlink.
>From here individual subsystems can be updated to set netlink_ext_ack as
needed.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Johan Hedberg says:
====================
pull request: bluetooth-next 2017-04-14
Here's the main batch of Bluetooth & 802.15.4 patches for the 4.12
kernel.
- Many fixes to 6LoWPAN, in particular for BLE
- New CA8210 IEEE 802.15.4 device driver (accounting for most of the
lines of code added in this pull request)
- Added Nokia Bluetooth (UART) HCI driver
- Some serdev & TTY changes that are dependencies for the Nokia
driver (with acks from relevant maintainers and an agreement that
these come through the bluetooth tree)
- Support for new Intel Bluetooth device
- Various other minor cleanups/fixes here and there
Please let me know if there are any issues pulling. Thanks.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts were simply overlapping changes. In the net/ipv4/route.c
case the code had simply moved around a little bit and the same fix
was made in both 'net' and 'net-next'.
In the net/sched/sch_generic.c case a fix in 'net' happened at
the same time that a new argument was added to qdisc_hash_add().
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
According to RFC 7668 U/L bit shall not be used:
https://wiki.tools.ietf.org/html/rfc7668#section-3.2.2 [Page 10]:
In the figure, letter 'b' represents a bit from the
Bluetooth device address, copied as is without any changes on any
bit. This means that no bit in the IID indicates whether the
underlying Bluetooth device address is public or random.
|0 1|1 3|3 4|4 6|
|0 5|6 1|2 7|8 3|
+----------------+----------------+----------------+----------------+
|bbbbbbbbbbbbbbbb|bbbbbbbb11111111|11111110bbbbbbbb|bbbbbbbbbbbbbbbb|
+----------------+----------------+----------------+----------------+
Because of this the code cannot figure out the address type from the IP
address anymore thus it makes no sense to use peer_lookup_ba as it needs
the peer address type.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds support for 48 bit 6LoWPAN address length
autoconfiguration which is the case for BTLE 6LoWPAN.
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
addrconf_ifdown() removes elements from the idev->addr_list without
holding the idev->lock.
If this happens while the loop in __ipv6_dev_get_saddr() is handling the
same element, that function ends up in an infinite loop:
NMI watchdog: BUG: soft lockup - CPU#1 stuck for 23s! [test:1719]
Call Trace:
ipv6_get_saddr_eval+0x13c/0x3a0
__ipv6_dev_get_saddr+0xe4/0x1f0
ipv6_dev_get_saddr+0x1b4/0x204
ip6_dst_lookup_tail+0xcc/0x27c
ip6_dst_lookup_flow+0x38/0x80
udpv6_sendmsg+0x708/0xba8
sock_sendmsg+0x18/0x30
SyS_sendto+0xb8/0xf8
syscall_common+0x34/0x58
Fixes: 6a923934c3 (Revert "ipv6: Revert optional address flusing on ifdown.")
Signed-off-by: Rabin Vincent <rabinv@axis.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
