ip6_route_info_create() invokes nexthop_get(), which increases the
refcount of the "nh".
When ip6_route_info_create() returns, local variable "nh" becomes
invalid, so the refcount should be decreased to keep refcount balanced.
The reference counting issue happens in one exception handling path of
ip6_route_info_create(). When nexthops can not be used with source
routing, the function forgets to decrease the refcnt increased by
nexthop_get(), causing a refcnt leak.
Fix this issue by pulling up the error source routing handling when
nexthops can not be used with source routing.
Fixes: f88d8ea67f ("ipv6: Plumb support for nexthop object in a fib6_info")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
One additional field btf_id is added to struct
bpf_ctx_arg_aux to store the precomputed btf_ids.
The btf_id is computed at build time with
BTF_ID_LIST or BTF_ID_LIST_GLOBAL macro definitions.
All existing bpf iterators are changed to used
pre-compute btf_ids.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200720163403.1393551-1-yhs@fb.com
Thomas reported a regression with IPv6 and anycast using the following
reproducer:
echo 1 > /proc/sys/net/ipv6/conf/all/forwarding
ip -6 a add fc12::1/16 dev lo
sleep 2
echo "pinging lo"
ping6 -c 2 fc12::
The conversion of addrconf_f6i_alloc to use ip6_route_info_create missed
the use of fib6_is_reject which checks addresses added to the loopback
interface and sets the REJECT flag as needed. Update fib6_is_reject for
loopback checks to handle RTF_ANYCAST addresses.
Fixes: c7a1ce397a ("ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create")
Reported-by: thomas.gambier@nexedi.com
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Brian reported a crash in IPv6 code when using rpfilter with a setup
running FRR and external nexthop objects. The root cause of the crash
is fib6_select_path setting fib6_nh in the result to NULL because of
an improper check for nexthop objects.
More specifically, rpfilter invokes ip6_route_lookup with flowi6_oif
set causing fib6_select_path to be called with have_oif_match set.
fib6_select_path has early check on have_oif_match and jumps to the
out label which presumes a builtin fib6_nh. This path is invalid for
nexthop objects; for external nexthops fib6_select_path needs to just
return if the fib6_nh has already been set in the result otherwise it
returns after the call to nexthop_path_fib6_result. Update the check
on have_oif_match to not bail on external nexthops.
Update selftests for this problem.
Fixes: f88d8ea67f ("ipv6: Plumb support for nexthop object in a fib6_info")
Reported-by: Brian Rak <brak@choopa.com>
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
It was reported that a considerable amount of cycles were spent on the
expensive indirect calls on fib6_rule_lookup. This patch introduces an
inline helper called pol_route_func that uses the indirect_call_wrappers
to avoid the indirect calls.
This patch saves around 50ns per call.
Performance was measured on the receiver by checking the amount of
syncookies that server was able to generate under a synflood load.
Traffic was generated using trafgen[1] which was pushing around 1Mpps on
a single queue. Receiver was using only one rx queue which help to
create a bottle neck and make the experiment rx-bounded.
These are the syncookies generated over 10s from the different runs:
Whithout the patch:
TcpExtSyncookiesSent 3553749 0.0
TcpExtSyncookiesSent 3550895 0.0
TcpExtSyncookiesSent 3553845 0.0
TcpExtSyncookiesSent 3541050 0.0
TcpExtSyncookiesSent 3539921 0.0
TcpExtSyncookiesSent 3557659 0.0
TcpExtSyncookiesSent 3526812 0.0
TcpExtSyncookiesSent 3536121 0.0
TcpExtSyncookiesSent 3529963 0.0
TcpExtSyncookiesSent 3536319 0.0
With the patch:
TcpExtSyncookiesSent 3611786 0.0
TcpExtSyncookiesSent 3596682 0.0
TcpExtSyncookiesSent 3606878 0.0
TcpExtSyncookiesSent 3599564 0.0
TcpExtSyncookiesSent 3601304 0.0
TcpExtSyncookiesSent 3609249 0.0
TcpExtSyncookiesSent 3617437 0.0
TcpExtSyncookiesSent 3608765 0.0
TcpExtSyncookiesSent 3620205 0.0
TcpExtSyncookiesSent 3601895 0.0
Without the patch the average is 354263 pkt/s or 2822 ns/pkt and with
the patch the average is 360738 pkt/s or 2772 ns/pkt which gives an
estimate of 50 ns per packet.
[1] http://netsniff-ng.org/
Changelog since v1:
- Change ordering in the ICW (Paolo Abeni)
Cc: Luigi Rizzo <lrizzo@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Brian Vazquez <brianvv@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces ecmp nexthops and nexthop groups
for mac fdb entries. In subsequent patches this is used
by the vxlan driver fdb entries. The use case is
E-VPN multihoming [1,2,3] which requires bridged vxlan traffic
to be load balanced to remote switches (vteps) belonging to
the same multi-homed ethernet segment (This is analogous to
a multi-homed LAG but over vxlan).
Changes include new nexthop flag NHA_FDB for nexthops
referenced by fdb entries. These nexthops only have ip.
This patch includes appropriate checks to avoid routes
referencing such nexthops.
example:
$ip nexthop add id 12 via 172.16.1.2 fdb
$ip nexthop add id 13 via 172.16.1.3 fdb
$ip nexthop add id 102 group 12/13 fdb
$bridge fdb add 02:02:00:00:00:13 dev vxlan1000 nhid 101 self
[1] E-VPN https://tools.ietf.org/html/rfc7432
[2] E-VPN VxLAN: https://tools.ietf.org/html/rfc8365
[3] LPC talk with mention of nexthop groups for L2 ecmp
http://vger.kernel.org/lpc_net2018_talks/scaling_bridge_fdb_database_slidesV3.pdf
v4 - fixed uninitialized variable reported by kernel test robot
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Prepare for better compat ioctl handling by moving the user copy out
of ipv6_route_ioctl.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the bpf verifier trace check into the new switch statement in
HEAD.
Resolve the overlapping changes in hinic, where bug fixes overlap
the addition of VF support.
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-05-14
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Merged tag 'perf-for-bpf-2020-05-06' from tip tree that includes CAP_PERFMON.
2) support for narrow loads in bpf_sock_addr progs and additional
helpers in cg-skb progs, from Andrey.
3) bpf benchmark runner, from Andrii.
4) arm and riscv JIT optimizations, from Luke.
5) bpf iterator infrastructure, from Yonghong.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit b121b341e5 ("bpf: Add PTR_TO_BTF_ID_OR_NULL
support") adds a field btf_id_or_null_non0_off to
bpf_prog->aux structure to indicate that the
first ctx argument is PTR_TO_BTF_ID reg_type and
all others are PTR_TO_BTF_ID_OR_NULL.
This approach does not really scale if we have
other different reg types in the future, e.g.,
a pointer to a buffer.
This patch enables bpf_iter targets registering ctx argument
reg types which may be different from the default one.
For example, for pointers to structures, the default reg_type
is PTR_TO_BTF_ID for tracing program. The target can register
a particular pointer type as PTR_TO_BTF_ID_OR_NULL which can
be used by the verifier to enforce accesses.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200513180221.2949882-1-yhs@fb.com
Change func bpf_iter_unreg_target() parameter from target
name to target reg_info, similar to bpf_iter_reg_target().
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200513180220.2949737-1-yhs@fb.com
Currently bpf_iter_reg_target takes parameters from target
and allocates memory to save them. This is really not
necessary, esp. in the future we may grow information
passed from targets to bpf_iter manager.
The patch refactors the code so target reg_info
becomes static and bpf_iter manager can just take
a reference to it.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200513180219.2949605-1-yhs@fb.com
This patch added netlink and ipv6_route targets, using
the same seq_ops (except show() and minor changes for stop())
for /proc/net/{netlink,ipv6_route}.
The net namespace for these targets are the current net
namespace at file open stage, similar to
/proc/net/{netlink,ipv6_route} reference counting
the net namespace at seq_file open stage.
Since module is not supported for now, ipv6_route is
supported only if the IPV6 is built-in, i.e., not compiled
as a module. The restriction can be lifted once module
is properly supported for bpf_iter.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200509175910.2476329-1-yhs@fb.com
We currently have to adjust ipv6 route gc_thresh/max_size depending
on number of cpus on a server, this makes very little sense.
If the kernels sets /proc/sys/net/ipv6/route/gc_thresh to 1024
and /proc/sys/net/ipv6/route/max_size to 4096, then we better
not track the percpu dst that our implementation uses.
Only routes not added (directly or indirectly) by the admin
should be tracked and limited.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: David Ahern <dsahern@kernel.org>
Cc: Maciej Żenczykowski <maze@google.com>
Acked-by: Wei Wang <weiwan@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
percpu_counter_add() uses a default batch size which is quite big
on platforms with 256 cpus. (2*256 -> 512)
This means dst_entries_get_fast() can be off by +/- 2*(nr_cpus^2)
(131072 on servers with 256 cpus)
Reduce the batch size to something more reasonable, and
add logic to ip6_dst_gc() to call dst_entries_get_slow()
before calling the _very_ expensive fib6_run_gc() function.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This reverts commit 19bda36c42:
| ipv6: add mtu lock check in __ip6_rt_update_pmtu
|
| Prior to this patch, ipv6 didn't do mtu lock check in ip6_update_pmtu.
| It leaded to that mtu lock doesn't really work when receiving the pkt
| of ICMPV6_PKT_TOOBIG.
|
| This patch is to add mtu lock check in __ip6_rt_update_pmtu just as ipv4
| did in __ip_rt_update_pmtu.
The above reasoning is incorrect. IPv6 *requires* icmp based pmtu to work.
There's already a comment to this effect elsewhere in the kernel:
$ git grep -p -B1 -A3 'RTAX_MTU lock'
net/ipv6/route.c=4813=
static int rt6_mtu_change_route(struct fib6_info *f6i, void *p_arg)
...
/* In IPv6 pmtu discovery is not optional,
so that RTAX_MTU lock cannot disable it.
We still use this lock to block changes
caused by addrconf/ndisc.
*/
This reverts to the pre-4.9 behaviour.
Cc: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Xin Long <lucien.xin@gmail.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Fixes: 19bda36c42 ("ipv6: add mtu lock check in __ip6_rt_update_pmtu")
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-05-01 (v2)
The following pull-request contains BPF updates for your *net-next* tree.
We've added 61 non-merge commits during the last 6 day(s) which contain
a total of 153 files changed, 6739 insertions(+), 3367 deletions(-).
The main changes are:
1) pulled work.sysctl from vfs tree with sysctl bpf changes.
2) bpf_link observability, from Andrii.
3) BTF-defined map in map, from Andrii.
4) asan fixes for selftests, from Andrii.
5) Allow bpf_map_lookup_elem for SOCKMAP and SOCKHASH, from Jakub.
6) production cloudflare classifier as a selftes, from Lorenz.
7) bpf_ktime_get_*_ns() helper improvements, from Maciej.
8) unprivileged bpftool feature probe, from Quentin.
9) BPF_ENABLE_STATS command, from Song.
10) enable bpf_[gs]etsockopt() helpers for sock_ops progs, from Stanislav.
11) enable a bunch of common helpers for cg-device, sysctl, sockopt progs,
from Stanislav.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Nik reported a bug with pcpu dst cache when nexthop objects are
used illustrated by the following:
$ ip netns add foo
$ ip -netns foo li set lo up
$ ip -netns foo addr add 2001:db8:11::1/128 dev lo
$ ip netns exec foo sysctl net.ipv6.conf.all.forwarding=1
$ ip li add veth1 type veth peer name veth2
$ ip li set veth1 up
$ ip addr add 2001:db8:10::1/64 dev veth1
$ ip li set dev veth2 netns foo
$ ip -netns foo li set veth2 up
$ ip -netns foo addr add 2001:db8:10::2/64 dev veth2
$ ip -6 nexthop add id 100 via 2001:db8:10::2 dev veth1
$ ip -6 route add 2001:db8:11::1/128 nhid 100
Create a pcpu entry on cpu 0:
$ taskset -a -c 0 ip -6 route get 2001:db8:11::1
Re-add the route entry:
$ ip -6 ro del 2001:db8:11::1
$ ip -6 route add 2001:db8:11::1/128 nhid 100
Route get on cpu 0 returns the stale pcpu:
$ taskset -a -c 0 ip -6 route get 2001:db8:11::1
RTNETLINK answers: Network is unreachable
While cpu 1 works:
$ taskset -a -c 1 ip -6 route get 2001:db8:11::1
2001:db8:11::1 from :: via 2001:db8:10::2 dev veth1 src 2001:db8:10::1 metric 1024 pref medium
Conversion of FIB entries to work with external nexthop objects
missed an important difference between IPv4 and IPv6 - how dst
entries are invalidated when the FIB changes. IPv4 has a per-network
namespace generation id (rt_genid) that is bumped on changes to the FIB.
Checking if a dst_entry is still valid means comparing rt_genid in the
rtable to the current value of rt_genid for the namespace.
IPv6 also has a per network namespace counter, fib6_sernum, but the
count is saved per fib6_node. With the per-node counter only dst_entries
based on fib entries under the node are invalidated when changes are
made to the routes - limiting the scope of invalidations. IPv6 uses a
reference in the rt6_info, 'from', to track the corresponding fib entry
used to create the dst_entry. When validating a dst_entry, the 'from'
is used to backtrack to the fib6_node and check the sernum of it to the
cookie passed to the dst_check operation.
With the inline format (nexthop definition inline with the fib6_info),
dst_entries cached in the fib6_nh have a 1:1 correlation between fib
entries, nexthop data and dst_entries. With external nexthops, IPv6
looks more like IPv4 which means multiple fib entries across disparate
fib6_nodes can all reference the same fib6_nh. That means validation
of dst_entries based on external nexthops needs to use the IPv4 format
- the per-network namespace counter.
Add sernum to rt6_info and set it when creating a pcpu dst entry. Update
rt6_get_cookie to return sernum if it is set and update dst_check for
IPv6 to look for sernum set and based the check on it if so. Finally,
rt6_get_pcpu_route needs to validate the cached entry before returning
a pcpu entry (similar to the rt_cache_valid calls in __mkroute_input and
__mkroute_output for IPv4).
This problem only affects routes using the new, external nexthops.
Thanks to the kbuild test robot for catching the IS_ENABLED needed
around rt_genid_ipv6 before I sent this out.
Fixes: 5b98324ebe ("ipv6: Allow routes to use nexthop objects")
Reported-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Tested-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current route nexthop API maintains user space compatibility
with old route API by default. Dumps and netlink notifications
support both new and old API format. In systems which have
moved to the new API, this compatibility mode cancels some
of the performance benefits provided by the new nexthop API.
This patch adds new sysctl nexthop_compat_mode which is on
by default but provides the ability to turn off compatibility
mode allowing systems to run entirely with the new routing
API. Old route API behaviour and support is not modified by this
sysctl.
Uses a single sysctl to cover both ipv4 and ipv6 following
other sysctls. Covers dumps and delete notifications as
suggested by David Ahern.
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Used in subsequent work to skip route delete
notifications on nexthop deletes.
Suggested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from userspace in common code. This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.
As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The build_state callback of lwtunnel doesn't contain the net namespace
structure yet. This patch will add it so we can check on specific
address configuration at creation time of rpl source routes.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previous changes to the IP routing code have removed all the
tests for the DS_HOST route flag.
Remove the flags and all the code that sets it.
Signed-off-by: David Laight <david.laight@aculab.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Convert the various uses of fallthrough comments to fallthrough;
Done via script
Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe@perches.com/
And by hand:
net/ipv6/ip6_fib.c has a fallthrough comment outside of an #ifdef block
that causes gcc to emit a warning if converted in-place.
So move the new fallthrough; inside the containing #ifdef/#endif too.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When splitting an RTA_MULTIPATH request into multiple routes and adding the
second and later components, we must not simply remove NLM_F_REPLACE but
instead replace it by NLM_F_CREATE. Otherwise, it may look like the netlink
message was malformed.
For example,
ip route add 2001:db8::1/128 dev dummy0
ip route change 2001:db8::1/128 nexthop via fe80::30:1 dev dummy0 \
nexthop via fe80::30:2 dev dummy0
results in the following warnings:
[ 1035.057019] IPv6: RTM_NEWROUTE with no NLM_F_CREATE or NLM_F_REPLACE
[ 1035.057517] IPv6: NLM_F_CREATE should be set when creating new route
This patch makes the nlmsg sequence look equivalent for __ip6_ins_rt() to
what it would get if the multipath route had been added in multiple netlink
operations:
ip route add 2001:db8::1/128 dev dummy0
ip route change 2001:db8::1/128 nexthop via fe80::30:1 dev dummy0
ip route append 2001:db8::1/128 nexthop via fe80::30:2 dev dummy0
Fixes: 2759647247 ("ipv6: fix ECMP route replacement")
Signed-off-by: Benjamin Poirier <bpoirier@cumulusnetworks.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In a similar fashion to previous patch, add "offload" and "trap"
indication to IPv6 routes.
This is done by using two unused bits in 'struct fib6_info' to hold
these indications. Capable drivers are expected to set these when
processing the various in-kernel route notifications.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that mlxsw is converted to use the new FIB notifications it is
possible to delete the old ones and use the new replace / append /
delete notifications.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When an entire multipath route is deleted, only emit a notification if
it is the first route in the node. Emit a replace notification in case
the last sibling is followed by another route. Otherwise, emit a delete
notification.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In a similar fashion to previous patches, only notify the new multipath
route if it is the first route in the node or if it was appended to such
route.
The type of the notification (replace vs. append) is determined based on
the number of routes added ('nhn') and the number of sibling routes. If
the two do not match, then an append notification should be sent.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The MTU update code is supposed to be invoked in response to real
networking events that update the PMTU. In IPv6 PMTU update function
__ip6_rt_update_pmtu() we called dst_confirm_neigh() to update neighbor
confirmed time.
But for tunnel code, it will call pmtu before xmit, like:
- tnl_update_pmtu()
- skb_dst_update_pmtu()
- ip6_rt_update_pmtu()
- __ip6_rt_update_pmtu()
- dst_confirm_neigh()
If the tunnel remote dst mac address changed and we still do the neigh
confirm, we will not be able to update neigh cache and ping6 remote
will failed.
So for this ip_tunnel_xmit() case, _EVEN_ if the MTU is changed, we
should not be invoking dst_confirm_neigh() as we have no evidence
of successful two-way communication at this point.
On the other hand it is also important to keep the neigh reachability fresh
for TCP flows, so we cannot remove this dst_confirm_neigh() call.
To fix the issue, we have to add a new bool parameter for dst_ops.update_pmtu
to choose whether we should do neigh update or not. I will add the parameter
in this patch and set all the callers to true to comply with the previous
way, and fix the tunnel code one by one on later patches.
v5: No change.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
dst_ops.update_pmtu to control whether we should do neighbor confirm.
Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.
Suggested-by: David Miller <davem@davemloft.net>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Minor conflict in drivers/s390/net/qeth_l2_main.c, kept the lock
from commit c8183f5489 ("s390/qeth: fix potential deadlock on
workqueue flush"), removed the code which was removed by commit
9897d583b0 ("s390/qeth: consolidate some duplicated HW cmd code").
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Use a per namespace counter, increment it on successful creation
of any route using the source address, decrement it on deletion
of such routes.
This allows us to check easily if the routing decision in the
current namespace depends on the packet source. Will be used
by the next patch.
Suggested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previously we will return directly if (!rt || !rt->fib6_nh.fib_nh_gw_family)
in function rt6_probe(), but after commit cc3a86c802
("ipv6: Change rt6_probe to take a fib6_nh"), the logic changed to
return if there is fib_nh_gw_family.
Fixes: cc3a86c802 ("ipv6: Change rt6_probe to take a fib6_nh")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
One conflict in the BPF samples Makefile, some fixes in 'net' whilst
we were converting over to Makefile.target rules in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
While looking at a syzbot KCSAN report [1], I found multiple
issues in this code :
1) fib6_nh->last_probe has an initial value of 0.
While probably okay on 64bit kernels, this causes an issue
on 32bit kernels since the time_after(jiffies, 0 + interval)
might be false ~24 days after boot (for HZ=1000)
2) The data-race found by KCSAN
I could use READ_ONCE() and WRITE_ONCE(), but we also can
take the opportunity of not piling-up too many rt6_probe_deferred()
works by using instead cmpxchg() so that only one cpu wins the race.
[1]
BUG: KCSAN: data-race in find_match / find_match
write to 0xffff8880bb7aabe8 of 8 bytes by interrupt on cpu 1:
rt6_probe net/ipv6/route.c:663 [inline]
find_match net/ipv6/route.c:757 [inline]
find_match+0x5bd/0x790 net/ipv6/route.c:733
__find_rr_leaf+0xe3/0x780 net/ipv6/route.c:831
find_rr_leaf net/ipv6/route.c:852 [inline]
rt6_select net/ipv6/route.c:896 [inline]
fib6_table_lookup+0x383/0x650 net/ipv6/route.c:2164
ip6_pol_route+0xee/0x5c0 net/ipv6/route.c:2200
ip6_pol_route_output+0x48/0x60 net/ipv6/route.c:2452
fib6_rule_lookup+0x3d6/0x470 net/ipv6/fib6_rules.c:117
ip6_route_output_flags_noref+0x16b/0x230 net/ipv6/route.c:2484
ip6_route_output_flags+0x50/0x1a0 net/ipv6/route.c:2497
ip6_dst_lookup_tail+0x25d/0xc30 net/ipv6/ip6_output.c:1049
ip6_dst_lookup_flow+0x68/0x120 net/ipv6/ip6_output.c:1150
inet6_csk_route_socket+0x2f7/0x420 net/ipv6/inet6_connection_sock.c:106
inet6_csk_xmit+0x91/0x1f0 net/ipv6/inet6_connection_sock.c:121
__tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169
tcp_transmit_skb net/ipv4/tcp_output.c:1185 [inline]
tcp_xmit_probe_skb+0x19b/0x1d0 net/ipv4/tcp_output.c:3735
read to 0xffff8880bb7aabe8 of 8 bytes by interrupt on cpu 0:
rt6_probe net/ipv6/route.c:657 [inline]
find_match net/ipv6/route.c:757 [inline]
find_match+0x521/0x790 net/ipv6/route.c:733
__find_rr_leaf+0xe3/0x780 net/ipv6/route.c:831
find_rr_leaf net/ipv6/route.c:852 [inline]
rt6_select net/ipv6/route.c:896 [inline]
fib6_table_lookup+0x383/0x650 net/ipv6/route.c:2164
ip6_pol_route+0xee/0x5c0 net/ipv6/route.c:2200
ip6_pol_route_output+0x48/0x60 net/ipv6/route.c:2452
fib6_rule_lookup+0x3d6/0x470 net/ipv6/fib6_rules.c:117
ip6_route_output_flags_noref+0x16b/0x230 net/ipv6/route.c:2484
ip6_route_output_flags+0x50/0x1a0 net/ipv6/route.c:2497
ip6_dst_lookup_tail+0x25d/0xc30 net/ipv6/ip6_output.c:1049
ip6_dst_lookup_flow+0x68/0x120 net/ipv6/ip6_output.c:1150
inet6_csk_route_socket+0x2f7/0x420 net/ipv6/inet6_connection_sock.c:106
inet6_csk_xmit+0x91/0x1f0 net/ipv6/inet6_connection_sock.c:121
__tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 18894 Comm: udevd Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Fixes: cc3a86c802 ("ipv6: Change rt6_probe to take a fib6_nh")
Fixes: f547fac624 ("ipv6: rate-limit probes for neighbourless routes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The same code which recognizes ICMP error packets is duplicated several
times. Use the icmp_is_err() and icmpv6_is_err() helpers instead, which
do the same thing.
ip_multipath_l3_keys() and tcf_nat_act() didn't check for all the error types,
assume that they should instead.
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Faster jhash2() can be used instead of jhash(), since
IPv6 addresses have the needed alignment requirement.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is the equivalent of commit 2c6b55f45d ("ipv6: fix neighbour
resolution with raw socket") for ip6_confirm_neigh(): we can send a
packet with MSG_CONFIRM on a raw socket for a connected route, so the
gateway would be :: here, and we should pick the next hop using
rt6_nexthop() instead.
This was found by code review and, to the best of my knowledge, doesn't
actually fix a practical issue: the destination address from the packet
is not considered while confirming a neighbour, as ip6_confirm_neigh()
calls choose_neigh_daddr() without passing the packet, so there are no
similar issues as the one fixed by said commit.
A possible source of issues with the existing implementation might come
from the fact that, if we have a cached dst, we won't consider it,
while rt6_nexthop() takes care of that. I might just not be creative
enough to find a practical problem here: the only way to affect this
with cached routes is to have one coming from an ICMPv6 redirect, but
if the next hop is a directly connected host, there should be no
topology for which a redirect applies here, and tests with redirected
routes show no differences for MSG_CONFIRM (and MSG_PROBE) packets on
raw sockets destined to a directly connected host.
However, directly using the dst gateway here is not consistent anymore
with neighbour resolution, and, in general, as we want the next hop,
using rt6_nexthop() looks like the only sane way to fetch it.
Reported-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Guillaume Nault <gnault@redhat.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes a stupid bug I recently introduced...
ip6_route_info_create() returns an ERR_PTR(err) and not a NULL on error.
Fixes: d55a2e374a ("net-ipv6: fix excessive RTF_ADDRCONF flag on ::1/128 local route (and others)'")
Cc: David Ahern <dsahern@gmail.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When creating a v4 route that uses a v6 nexthop from a nexthop group.
Allow the kernel to properly send the nexthop as v6 via the RTA_VIA
attribute.
Broken behavior:
$ ip nexthop add via fe80::9 dev eth0
$ ip nexthop show
id 1 via fe80::9 dev eth0 scope link
$ ip route add 4.5.6.7/32 nhid 1
$ ip route show
default via 10.0.2.2 dev eth0
4.5.6.7 nhid 1 via 254.128.0.0 dev eth0
10.0.2.0/24 dev eth0 proto kernel scope link src 10.0.2.15
$
Fixed behavior:
$ ip nexthop add via fe80::9 dev eth0
$ ip nexthop show
id 1 via fe80::9 dev eth0 scope link
$ ip route add 4.5.6.7/32 nhid 1
$ ip route show
default via 10.0.2.2 dev eth0
4.5.6.7 nhid 1 via inet6 fe80::9 dev eth0
10.0.2.0/24 dev eth0 proto kernel scope link src 10.0.2.15
$
v2, v3: Addresses code review comments from David Ahern
Fixes: dcb1ecb50e (“ipv4: Prepare for fib6_nh from a nexthop object”)
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A change to the core nla helpers was missed during the push of
the nexthop changes. rt6_fill_node_nexthop should be calling
nla_nest_start_noflag not nla_nest_start. Currently, iproute2
does not print multipath data because of parsing issues with
the attribute.
Fixes: f88d8ea67f ("ipv6: Plumb support for nexthop object in a fib6_info")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a subtle change in behaviour introduced by:
commit c7a1ce397a
'ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create'
Before that patch /proc/net/ipv6_route includes:
00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000003 00000000 80200001 lo
Afterwards /proc/net/ipv6_route includes:
00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000002 00000000 80240001 lo
ie. the above commit causes the ::1/128 local (automatic) route to be flagged with RTF_ADDRCONF (0x040000).
AFAICT, this is incorrect since these routes are *not* coming from RA's.
As such, this patch restores the old behaviour.
Fixes: c7a1ce397a ("ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create")
Cc: David Ahern <dsahern@gmail.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Simplify the unlock path in __ip6_rt_update_pmtu by using a
single point where rcu_read_unlock is called.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The nexthop path in rt6_update_exception_stamp_rt needs to call
rcu_read_unlock if it fails to find a fib6_nh match rather than
just returning.
Fixes: e659ba31d8 ("ipv6: Handle all fib6_nh in a nexthop in exception handling")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
