Pablo Neira Ayuso says:
====================
Netfilter/IPVS fixes for net
The following patchset contains Netfilter/IPVS fixes for your net tree,
they are:
1) Fix SIP conntrack with phones sending session descriptions for different
media types but same port numbers, from Florian Westphal.
2) Fix incorrect rtnl_lock mutex logic from IPVS sync thread, from Julian
Anastasov.
3) Skip compat array allocation in ebtables if there is no entries, also
from Florian.
4) Do not lose left/right bits when shifting marks from xt_connmark, from
Jack Ma.
5) Silence false positive memleak in conntrack extensions, from Cong Wang.
6) Fix CONFIG_NF_REJECT_IPV6=m link problems, from Arnd Bergmann.
7) Cannot kfree rule that is already in list in nf_tables, switch order
so this error handling is not required, from Florian Westphal.
8) Release set name in error path, from Florian.
9) include kmemleak.h in nf_conntrack_extend.c, from Stepheh Rothwell.
10) NAT chain and extensions depend on NF_TABLES.
11) Out of bound access when renaming chains, from Taehee Yoo.
12) Incorrect casting in xt_connmark leads to wrong bitshifting.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
KMSAN reported use of uninit-value that I tracked to lack
of proper size check on RTA_TABLE attribute.
I also believe RTA_PREFSRC lacks a similar check.
Fixes: 86872cb579 ("[IPv6] route: FIB6 configuration using struct fib6_config")
Fixes: c3968a857a ("ipv6: RTA_PREFSRC support for ipv6 route source address selection")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move these options inside the scope of the 'if' NF_TABLES and
NF_TABLES_IPV6 dependencies. This patch fixes:
net/ipv6/netfilter/nft_chain_nat_ipv6.o: In function `nft_nat_do_chain':
>> net/ipv6/netfilter/nft_chain_nat_ipv6.c:37: undefined reference to `nft_do_chain'
net/ipv6/netfilter/nft_chain_nat_ipv6.o: In function `nft_chain_nat_ipv6_exit':
>> net/ipv6/netfilter/nft_chain_nat_ipv6.c:94: undefined reference to `nft_unregister_chain_type'
net/ipv6/netfilter/nft_chain_nat_ipv6.o: In function `nft_chain_nat_ipv6_init':
>> net/ipv6/netfilter/nft_chain_nat_ipv6.c:87: undefined reference to `nft_register_chain_type'
that happens with:
CONFIG_NF_TABLES=m
CONFIG_NFT_CHAIN_NAT_IPV6=y
Fixes: 02c7b25e5f ("netfilter: nf_tables: build-in filter chain type")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
At the end of ip6_forward(), IPSTATS_MIB_OUTFORWDATAGRAMS and
IPSTATS_MIB_OUTOCTETS are incremented immediately before the NF_HOOK call
for NFPROTO_IPV6 / NF_INET_FORWARD. As a result, these counters get
incremented regardless of whether or not the netfilter hook allows the
packet to continue being processed. This change increments the counters
in ip6_forward_finish() so that it will not happen if the netfilter hook
chooses to terminate the packet, which is similar to how IPv4 works.
Signed-off-by: Jeff Barnhill <0xeffeff@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use valid_name() to make sure user does not provide illegal
device name.
Fixes: ed1efb2aef ("ipv6: Add support for IPsec virtual tunnel interfaces")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use valid_name() to make sure user does not provide illegal
device name.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Giving an integer to proc_doulongvec_minmax() is dangerous on 64bit arches,
since linker might place next to it a non zero value preventing a change
to ip6frag_low_thresh.
ip6frag_low_thresh is not used anymore in the kernel, but we do not
want to prematuraly break user scripts wanting to change it.
Since specifying a minimal value of 0 for proc_doulongvec_minmax()
is moot, let's remove these zero values in all defrag units.
Fixes: 6e00f7dd5e ("ipv6: frags: fix /proc/sys/net/ipv6/ip6frag_low_thresh")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit 694aba690d ("ipv4: factorize sk_wmem_alloc updates
done by __ip_append_data()") and commit 1f4c6eb240 ("ipv6:
factorize sk_wmem_alloc updates done by __ip6_append_data()"),
when transmitting sub MTU datagram, an addtional, unneeded atomic
operation is performed in ip*_append_data() to update wmem_alloc:
in the above condition the delta is 0.
The above cause small but measurable performance regression in UDP
xmit tput test with packet size below MTU.
This change avoids such overhead updating wmem_alloc only if
wmem_alloc_delta is non zero.
The error path is left intentionally unmodified: it's a slow path
and simplicity is preferred to performances.
Fixes: 694aba690d ("ipv4: factorize sk_wmem_alloc updates done by __ip_append_data()")
Fixes: 1f4c6eb240 ("ipv6: factorize sk_wmem_alloc updates done by __ip6_append_data()")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A new RTF_CACHE route can be created between ip6_sk_dst_lookup_flow()
and ip6_dst_store() calls in udpv6_sendmsg(), when datagram sending
results to ICMPV6_PKT_TOOBIG error:
udp_v6_send_skb(), for example with vti6 tunnel:
vti6_xmit(), get ICMPV6_PKT_TOOBIG error
skb_dst_update_pmtu(), can create a RTF_CACHE clone
icmpv6_send()
...
udpv6_err()
ip6_sk_update_pmtu()
ip6_update_pmtu(), can create a RTF_CACHE clone
...
ip6_datagram_dst_update()
ip6_dst_store()
And after commit 33c162a980 ("ipv6: datagram: Update dst cache of
a connected datagram sk during pmtu update"), the UDPv6 error handler
can update socket's dst cache, but it can happen before the update in
the end of udpv6_sendmsg(), preventing getting the new dst cache on
the next udpv6_sendmsg() calls.
In order to fix it, save dst in a connected socket only if the current
socket's dst cache is invalid.
The previous patch prepared ip6_sk_dst_lookup_flow() to do that with
the new argument, and this patch enables it in udpv6_sendmsg().
Fixes: 33c162a980 ("ipv6: datagram: Update dst cache of a connected datagram sk during pmtu update")
Fixes: 45e4fd2668 ("ipv6: Only create RTF_CACHE routes after encountering pmtu exception")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This should make it consistent with ip6_sk_dst_lookup_flow()
that is accepting the new 'connected' parameter of type bool.
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add 'connected' parameter to ip6_sk_dst_lookup_flow() and update
the cache only if ip6_sk_dst_check() returns NULL and a socket
is connected.
The function is used as before, the new behavior for UDP sockets
in udpv6_sendmsg() will be enabled in the next patch.
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move commonly used pattern of ip6_dst_store() usage to a separate
function - ip6_sk_dst_store_flow(), which will check the addresses
for equality using the flow information, before saving them.
There is no functional changes in this patch. In addition, it will
be used in the next patch, in ip6_sk_dst_lookup_flow().
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I forgot to change ip6frag_low_thresh proc_handler
from proc_dointvec_minmax to proc_doulongvec_minmax
Fixes: 3e67f106f6 ("inet: frags: break the 2GB limit for frags storage")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Minor conflicts in drivers/net/ethernet/mellanox/mlx5/core/en_rep.c,
we had some overlapping changes:
1) In 'net' MLX5E_PARAMS_LOG_{SQ,RQ}_SIZE -->
MLX5E_REP_PARAMS_LOG_{SQ,RQ}_SIZE
2) In 'net-next' params->log_rq_size is renamed to be
params->log_rq_mtu_frames.
3) In 'net-next' params->hard_mtu is added.
Signed-off-by: David S. Miller <davem@davemloft.net>
While testing my inet defrag changes, I found that the senders
could spend ~20% of cpu cycles in skb_set_owner_w() updating
sk->sk_wmem_alloc for every fragment they cook, competing
with TX completion of prior skbs possibly happening on another cpus.
The solution to this problem is to use alloc_skb() instead
of sock_wmalloc() and manually perform a single sk_wmem_alloc change.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
'tunnel' was already set at the start of ip6erspan_tap_init().
Fixes: 5a963eb61b ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-03-31
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Add raw BPF tracepoint API in order to have a BPF program type that
can access kernel internal arguments of the tracepoints in their
raw form similar to kprobes based BPF programs. This infrastructure
also adds a new BPF_RAW_TRACEPOINT_OPEN command to BPF syscall which
returns an anon-inode backed fd for the tracepoint object that allows
for automatic detach of the BPF program resp. unregistering of the
tracepoint probe on fd release, from Alexei.
2) Add new BPF cgroup hooks at bind() and connect() entry in order to
allow BPF programs to reject, inspect or modify user space passed
struct sockaddr, and as well a hook at post bind time once the port
has been allocated. They are used in FB's container management engine
for implementing policy, replacing fragile LD_PRELOAD wrapper
intercepting bind() and connect() calls that only works in limited
scenarios like glibc based apps but not for other runtimes in
containerized applications, from Andrey.
3) BPF_F_INGRESS flag support has been added to sockmap programs for
their redirect helper call bringing it in line with cls_bpf based
programs. Support is added for both variants of sockmap programs,
meaning for tx ULP hooks as well as recv skb hooks, from John.
4) Various improvements on BPF side for the nfp driver, besides others
this work adds BPF map update and delete helper call support from
the datapath, JITing of 32 and 64 bit XADD instructions as well as
offload support of bpf_get_prandom_u32() call. Initial implementation
of nfp packet cache has been tackled that optimizes memory access
(see merge commit for further details), from Jakub and Jiong.
5) Removal of struct bpf_verifier_env argument from the print_bpf_insn()
API has been done in order to prepare to use print_bpf_insn() soon
out of perf tool directly. This makes the print_bpf_insn() API more
generic and pushes the env into private data. bpftool is adjusted
as well with the print_bpf_insn() argument removal, from Jiri.
6) Couple of cleanups and prep work for the upcoming BTF (BPF Type
Format). The latter will reuse the current BPF verifier log as
well, thus bpf_verifier_log() is further generalized, from Martin.
7) For bpf_getsockopt() and bpf_setsockopt() helpers, IPv4 IP_TOS read
and write support has been added in similar fashion to existing
IPv6 IPV6_TCLASS socket option we already have, from Nikita.
8) Fixes in recent sockmap scatterlist API usage, which did not use
sg_init_table() for initialization thus triggering a BUG_ON() in
scatterlist API when CONFIG_DEBUG_SG was enabled. This adds and
uses a small helper sg_init_marker() to properly handle the affected
cases, from Prashant.
9) Let the BPF core follow IDR code convention and therefore use the
idr_preload() and idr_preload_end() helpers, which would also help
idr_alloc_cyclic() under GFP_ATOMIC to better succeed under memory
pressure, from Shaohua.
10) Last but not least, a spelling fix in an error message for the
BPF cookie UID helper under BPF sample code, from Colin.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
nf_ct_frag6_queue() uses skb->cb[] to store the fragment offset,
meaning that we could use two cache lines per skb when finding
the insertion point, if for some reason inet6_skb_parm size
is increased in the future.
By using skb->ip_defrag_offset instead of skb->cb[] we pack all the fields
in a single cache line, matching what we did for IPv4.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ip6_frag_queue uses skb->cb[] to store the fragment offset, meaning that
we could use two cache lines per skb when finding the insertion point,
if for some reason inet6_skb_parm size is increased in the future.
By using skb->ip_defrag_offset instead of skb->cb[], we pack all
the fields in a single cache line, matching what we did for IPv4.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make it similar to IPv4 ip_expire(), and release the lock
before calling icmp functions.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some users are willing to provision huge amounts of memory to be able
to perform reassembly reasonnably well under pressure.
Current memory tracking is using one atomic_t and integers.
Switch to atomic_long_t so that 64bit arches can use more than 2GB,
without any cost for 32bit arches.
Note that this patch avoids an overflow error, if high_thresh was set
to ~2GB, since this test in inet_frag_alloc() was never true :
if (... || frag_mem_limit(nf) > nf->high_thresh)
Tested:
$ echo 16000000000 >/proc/sys/net/ipv4/ipfrag_high_thresh
<frag DDOS>
$ grep FRAG /proc/net/sockstat
FRAG: inuse 14705885 memory 16000002880
$ nstat -n ; sleep 1 ; nstat | grep Reas
IpReasmReqds 3317150 0.0
IpReasmFails 3317112 0.0
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This function is obsolete, after rhashtable addition to inet defrag.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This refactors ip_expire() since one indentation level is removed.
Note: in the future, we should try hard to avoid the skb_clone()
since this is a serious performance cost.
Under DDOS, the ICMP message wont be sent because of rate limits.
Fact that ip6_expire_frag_queue() does not use skb_clone() is
disturbing too. Presumably IPv6 should have the same
issue than the one we fixed in commit ec4fbd6475
("inet: frag: release spinlock before calling icmp_send()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove sum_frag_mem_limit(), ip_frag_mem() & ip6_frag_mem()
Also since we use rhashtable we can bring back the number of fragments
in "grep FRAG /proc/net/sockstat /proc/net/sockstat6" that was
removed in commit 434d305405 ("inet: frag: don't account number
of fragment queues")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some applications still rely on IP fragmentation, and to be fair linux
reassembly unit is not working under any serious load.
It uses static hash tables of 1024 buckets, and up to 128 items per bucket (!!!)
A work queue is supposed to garbage collect items when host is under memory
pressure, and doing a hash rebuild, changing seed used in hash computations.
This work queue blocks softirqs for up to 25 ms when doing a hash rebuild,
occurring every 5 seconds if host is under fire.
Then there is the problem of sharing this hash table for all netns.
It is time to switch to rhashtables, and allocate one of them per netns
to speedup netns dismantle, since this is a critical metric these days.
Lookup is now using RCU. A followup patch will even remove
the refcount hold/release left from prior implementation and save
a couple of atomic operations.
Before this patch, 16 cpus (16 RX queue NIC) could not handle more
than 1 Mpps frags DDOS.
After the patch, I reach 9 Mpps without any tuning, and can use up to 2GB
of storage for the fragments (exact number depends on frags being evicted
after timeout)
$ grep FRAG /proc/net/sockstat
FRAG: inuse 1966916 memory 2140004608
A followup patch will change the limits for 64bit arches.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Florian Westphal <fw@strlen.de>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Alexander Aring <alex.aring@gmail.com>
Cc: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We want to call inet_frags_init() earlier.
This is a prereq to "inet: frags: use rhashtables for reassembly units"
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to simplify the API, add a pointer to struct inet_frags.
This will allow us to make things less complex.
These functions no longer have a struct inet_frags parameter :
inet_frag_destroy(struct inet_frag_queue *q /*, struct inet_frags *f */)
inet_frag_put(struct inet_frag_queue *q /*, struct inet_frags *f */)
inet_frag_kill(struct inet_frag_queue *q /*, struct inet_frags *f */)
inet_frags_exit_net(struct netns_frags *nf /*, struct inet_frags *f */)
ip6_expire_frag_queue(struct net *net, struct frag_queue *fq)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We will soon initialize one rhashtable per struct netns_frags
in inet_frags_init_net().
This patch changes the return value to eventually propagate an
error.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
"Post-hooks" are hooks that are called right before returning from
sys_bind. At this time IP and port are already allocated and no further
changes to `struct sock` can happen before returning from sys_bind but
BPF program has a chance to inspect the socket and change sys_bind
result.
Specifically it can e.g. inspect what port was allocated and if it
doesn't satisfy some policy, BPF program can force sys_bind to fail and
return EPERM to user.
Another example of usage is recording the IP:port pair to some map to
use it in later calls to sys_connect. E.g. if some TCP server inside
cgroup was bound to some IP:port_n, it can be recorded to a map. And
later when some TCP client inside same cgroup is trying to connect to
127.0.0.1:port_n, BPF hook for sys_connect can override the destination
and connect application to IP:port_n instead of 127.0.0.1:port_n. That
helps forcing all applications inside a cgroup to use desired IP and not
break those applications if they e.g. use localhost to communicate
between each other.
== Implementation details ==
Post-hooks are implemented as two new attach types
`BPF_CGROUP_INET4_POST_BIND` and `BPF_CGROUP_INET6_POST_BIND` for
existing prog type `BPF_PROG_TYPE_CGROUP_SOCK`.
Separate attach types for IPv4 and IPv6 are introduced to avoid access
to IPv6 field in `struct sock` from `inet_bind()` and to IPv4 field from
`inet6_bind()` since those fields might not make sense in such cases.
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
== The problem ==
See description of the problem in the initial patch of this patch set.
== The solution ==
The patch provides much more reliable in-kernel solution for the 2nd
part of the problem: making outgoing connecttion from desired IP.
It adds new attach types `BPF_CGROUP_INET4_CONNECT` and
`BPF_CGROUP_INET6_CONNECT` for program type
`BPF_PROG_TYPE_CGROUP_SOCK_ADDR` that can be used to override both
source and destination of a connection at connect(2) time.
Local end of connection can be bound to desired IP using newly
introduced BPF-helper `bpf_bind()`. It allows to bind to only IP though,
and doesn't support binding to port, i.e. leverages
`IP_BIND_ADDRESS_NO_PORT` socket option. There are two reasons for this:
* looking for a free port is expensive and can affect performance
significantly;
* there is no use-case for port.
As for remote end (`struct sockaddr *` passed by user), both parts of it
can be overridden, remote IP and remote port. It's useful if an
application inside cgroup wants to connect to another application inside
same cgroup or to itself, but knows nothing about IP assigned to the
cgroup.
Support is added for IPv4 and IPv6, for TCP and UDP.
IPv4 and IPv6 have separate attach types for same reason as sys_bind
hooks, i.e. to prevent reading from / writing to e.g. user_ip6 fields
when user passes sockaddr_in since it'd be out-of-bound.
== Implementation notes ==
The patch introduces new field in `struct proto`: `pre_connect` that is
a pointer to a function with same signature as `connect` but is called
before it. The reason is in some cases BPF hooks should be called way
before control is passed to `sk->sk_prot->connect`. Specifically
`inet_dgram_connect` autobinds socket before calling
`sk->sk_prot->connect` and there is no way to call `bpf_bind()` from
hooks from e.g. `ip4_datagram_connect` or `ip6_datagram_connect` since
it'd cause double-bind. On the other hand `proto.pre_connect` provides a
flexible way to add BPF hooks for connect only for necessary `proto` and
call them at desired time before `connect`. Since `bpf_bind()` is
allowed to bind only to IP and autobind in `inet_dgram_connect` binds
only port there is no chance of double-bind.
bpf_bind() sets `force_bind_address_no_port` to bind to only IP despite
of value of `bind_address_no_port` socket field.
bpf_bind() sets `with_lock` to `false` when calling to __inet_bind()
and __inet6_bind() since all call-sites, where bpf_bind() is called,
already hold socket lock.
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Refactor `bind()` code to make it ready to be called from BPF helper
function `bpf_bind()` (will be added soon). Implementation of
`inet_bind()` and `inet6_bind()` is separated into `__inet_bind()` and
`__inet6_bind()` correspondingly. These function can be used from both
`sk_prot->bind` and `bpf_bind()` contexts.
New functions have two additional arguments.
`force_bind_address_no_port` forces binding to IP only w/o checking
`inet_sock.bind_address_no_port` field. It'll allow to bind local end of
a connection to desired IP in `bpf_bind()` w/o changing
`bind_address_no_port` field of a socket. It's useful since `bpf_bind()`
can return an error and we'd need to restore original value of
`bind_address_no_port` in that case if we changed this before calling to
the helper.
`with_lock` specifies whether to lock socket when working with `struct
sk` or not. The argument is set to `true` for `sk_prot->bind`, i.e. old
behavior is preserved. But it will be set to `false` for `bpf_bind()`
use-case. The reason is all call-sites, where `bpf_bind()` will be
called, already hold that socket lock.
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
== The problem ==
There is a use-case when all processes inside a cgroup should use one
single IP address on a host that has multiple IP configured. Those
processes should use the IP for both ingress and egress, for TCP and UDP
traffic. So TCP/UDP servers should be bound to that IP to accept
incoming connections on it, and TCP/UDP clients should make outgoing
connections from that IP. It should not require changing application
code since it's often not possible.
Currently it's solved by intercepting glibc wrappers around syscalls
such as `bind(2)` and `connect(2)`. It's done by a shared library that
is preloaded for every process in a cgroup so that whenever TCP/UDP
server calls `bind(2)`, the library replaces IP in sockaddr before
passing arguments to syscall. When application calls `connect(2)` the
library transparently binds the local end of connection to that IP
(`bind(2)` with `IP_BIND_ADDRESS_NO_PORT` to avoid performance penalty).
Shared library approach is fragile though, e.g.:
* some applications clear env vars (incl. `LD_PRELOAD`);
* `/etc/ld.so.preload` doesn't help since some applications are linked
with option `-z nodefaultlib`;
* other applications don't use glibc and there is nothing to intercept.
== The solution ==
The patch provides much more reliable in-kernel solution for the 1st
part of the problem: binding TCP/UDP servers on desired IP. It does not
depend on application environment and implementation details (whether
glibc is used or not).
It adds new eBPF program type `BPF_PROG_TYPE_CGROUP_SOCK_ADDR` and
attach types `BPF_CGROUP_INET4_BIND` and `BPF_CGROUP_INET6_BIND`
(similar to already existing `BPF_CGROUP_INET_SOCK_CREATE`).
The new program type is intended to be used with sockets (`struct sock`)
in a cgroup and provided by user `struct sockaddr`. Pointers to both of
them are parts of the context passed to programs of newly added types.
The new attach types provides hooks in `bind(2)` system call for both
IPv4 and IPv6 so that one can write a program to override IP addresses
and ports user program tries to bind to and apply such a program for
whole cgroup.
== Implementation notes ==
[1]
Separate attach types for `AF_INET` and `AF_INET6` are added
intentionally to prevent reading/writing to offsets that don't make
sense for corresponding socket family. E.g. if user passes `sockaddr_in`
it doesn't make sense to read from / write to `user_ip6[]` context
fields.
[2]
The write access to `struct bpf_sock_addr_kern` is implemented using
special field as an additional "register".
There are just two registers in `sock_addr_convert_ctx_access`: `src`
with value to write and `dst` with pointer to context that can't be
changed not to break later instructions. But the fields, allowed to
write to, are not available directly and to access them address of
corresponding pointer has to be loaded first. To get additional register
the 1st not used by `src` and `dst` one is taken, its content is saved
to `bpf_sock_addr_kern.tmp_reg`, then the register is used to load
address of pointer field, and finally the register's content is restored
from the temporary field after writing `src` value.
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Donald reported that IPv6 route leaking between VRFs is not working.
The root cause is the strict argument in the call to rt6_lookup when
validating the nexthop spec.
ip6_route_check_nh validates the gateway and device (if given) of a
route spec. It in turn could call rt6_lookup (e.g., lookup in a given
table did not succeed so it falls back to a full lookup) and if so
sets the strict argument to 1. That means if the egress device is given,
the route lookup needs to return a result with the same device. This
strict requirement does not work with VRFs (IPv4 or IPv6) because the
oif in the flow struct is overridden with the index of the VRF device
to trigger a match on the l3mdev rule and force the lookup to its table.
The right long term solution is to add an l3mdev index to the flow
struct such that the oif is not overridden. That solution will not
backport well, so this patch aims for a simpler solution to relax the
strict argument if the route spec device is an l3mdev slave. As done
in other places, use the FLOWI_FLAG_SKIP_NH_OIF to know that the
RT6_LOOKUP_F_IFACE flag needs to be removed.
Fixes: ca254490c8 ("net: Add VRF support to IPv6 stack")
Reported-by: Donald Sharp <sharpd@cumulusnetworks.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Enabling TSO can lead to abysmal performances when using seg6 in
encap mode, such as with the ixgbe driver. This patch adds a call to
iptunnel_handle_offloads() to remove the encapsulation bit if needed.
Before:
root@comp4-seg6bpf:~# iperf3 -c fc00::55
Connecting to host fc00::55, port 5201
[ 4] local fc45::4 port 36592 connected to fc00::55 port 5201
[ ID] Interval Transfer Bandwidth Retr Cwnd
[ 4] 0.00-1.00 sec 196 KBytes 1.60 Mbits/sec 47 6.66 KBytes
[ 4] 1.00-2.00 sec 304 KBytes 2.49 Mbits/sec 100 5.33 KBytes
[ 4] 2.00-3.00 sec 284 KBytes 2.32 Mbits/sec 92 5.33 KBytes
After:
root@comp4-seg6bpf:~# iperf3 -c fc00::55
Connecting to host fc00::55, port 5201
[ 4] local fc45::4 port 43062 connected to fc00::55 port 5201
[ ID] Interval Transfer Bandwidth Retr Cwnd
[ 4] 0.00-1.00 sec 1.03 GBytes 8.89 Gbits/sec 0 743 KBytes
[ 4] 1.00-2.00 sec 1.03 GBytes 8.87 Gbits/sec 0 743 KBytes
[ 4] 2.00-3.00 sec 1.03 GBytes 8.87 Gbits/sec 0 743 KBytes
Reported-by: Tom Herbert <tom@quantonium.net>
Fixes: 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Signed-off-by: David Lebrun <dlebrun@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Do not allow setting ipv6 routes from userspace if disable_ipv6 has been
enabled. The issue can be triggered using the following reproducer:
- sysctl net.ipv6.conf.all.disable_ipv6=1
- ip -6 route add a🅱️c:d::/64 dev em1
- ip -6 route show
a🅱️c:d::/64 dev em1 metric 1024 pref medium
Fix it checking disable_ipv6 value in ip6_route_info_create routine
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter/IPVS updates for net-next
The following patchset contains Netfilter/IPVS updates for your net-next
tree. This batch comes with more input sanitization for xtables to
address bug reports from fuzzers, preparation works to the flowtable
infrastructure and assorted updates. In no particular order, they are:
1) Make sure userspace provides a valid standard target verdict, from
Florian Westphal.
2) Sanitize error target size, also from Florian.
3) Validate that last rule in basechain matches underflow/policy since
userspace assumes this when decoding the ruleset blob that comes
from the kernel, from Florian.
4) Consolidate hook entry checks through xt_check_table_hooks(),
patch from Florian.
5) Cap ruleset allocations at 512 mbytes, 134217728 rules and reject
very large compat offset arrays, so we have a reasonable upper limit
and fuzzers don't exercise the oom-killer. Patches from Florian.
6) Several WARN_ON checks on xtables mutex helper, from Florian.
7) xt_rateest now has a hashtable per net, from Cong Wang.
8) Consolidate counter allocation in xt_counters_alloc(), from Florian.
9) Earlier xt_table_unlock() call in {ip,ip6,arp,eb}tables, patch
from Xin Long.
10) Set FLOW_OFFLOAD_DIR_* to IP_CT_DIR_* definitions, patch from
Felix Fietkau.
11) Consolidate code through flow_offload_fill_dir(), also from Felix.
12) Inline ip6_dst_mtu_forward() just like ip_dst_mtu_maybe_forward()
to remove a dependency with flowtable and ipv6.ko, from Felix.
13) Cache mtu size in flow_offload_tuple object, this is safe for
forwarding as f87c10a8aa describes, from Felix.
14) Rename nf_flow_table.c to nf_flow_table_core.o, to simplify too
modular infrastructure, from Felix.
15) Add rt0, rt2 and rt4 IPv6 routing extension support, patch from
Ahmed Abdelsalam.
16) Remove unused parameter in nf_conncount_count(), from Yi-Hung Wei.
17) Support for counting only to nf_conncount infrastructure, patch
from Yi-Hung Wei.
18) Add strict NFT_CT_{SRC_IP,DST_IP,SRC_IP6,DST_IP6} key datatypes
to nft_ct.
19) Use boolean as return value from ipt_ah and from IPVS too, patch
from Gustavo A. R. Silva.
20) Remove useless parameters in nfnl_acct_overquota() and
nf_conntrack_broadcast_help(), from Taehee Yoo.
21) Use ipv6_addr_is_multicast() from xt_cluster, also from Taehee Yoo.
22) Statify nf_tables_obj_lookup_byhandle, patch from Fengguang Wu.
23) Fix typo in xt_limit, from Geert Uytterhoeven.
24) Do no use VLAs in Netfilter code, again from Gustavo.
25) Use ADD_COUNTER from ebtables, from Taehee Yoo.
26) Bitshift support for CONNMARK and MARK targets, from Jack Ma.
27) Use pr_*() and add pr_fmt(), from Arushi Singhal.
28) Add synproxy support to ctnetlink.
29) ICMP type and IGMP matching support for ebtables, patches from
Matthias Schiffer.
30) Support for the revision infrastructure to ebtables, from
Bernie Harris.
31) String match support for ebtables, also from Bernie.
32) Documentation for the new flowtable infrastructure.
33) Use generic comparison functions in ebt_stp, from Joe Perches.
34) Demodularize filter chains in nftables.
35) Register conntrack hooks in case nftables NAT chain is added.
36) Merge assignments with return in a couple of spots in the
Netfilter codebase, also from Arushi.
37) Document that xtables percpu counters are stored in the same
memory area, from Ben Hutchings.
38) Revert mark_source_chains() sanity checks that break existing
rulesets, from Florian Westphal.
39) Use is_zero_ether_addr() in the ipset codebase, from Joe Perches.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 0d7df906a0.
Valdis Kletnieks reported that xtables is broken in linux-next since
0d7df906a0 ("netfilter: x_tables: ensure last rule in base chain
matches underflow/policy"), as kernel rejects the (well-formed) ruleset:
[ 64.402790] ip6_tables: last base chain position 1136 doesn't match underflow 1344 (hook 1)
mark_source_chains is not the correct place for such a check, as it
terminates evaluation of a chain once it sees an unconditional verdict
(following rules are known to be unreachable). It seems preferrable to
fix libiptc instead, so remove this check again.
Fixes: 0d7df906a0 ("netfilter: x_tables: ensure last rule in base chain matches underflow/policy")
Reported-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Register conntrack hooks if the user adds NAT chains. Users get confused
with the existing behaviour since they will see no packets hitting this
chain until they add the first rule that refers to conntrack.
This patch adds new ->init() and ->free() indirections to chain types
that can be used by NAT chains to invoke the conntrack dependency.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
One module per supported filter chain family type takes too much memory
for very little code - too much modularization - place all chain filter
definitions in one single file.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use WARN_ON() instead since it should not happen that neither family
goes over NFPROTO_NUMPROTO nor there is already a chain of this type
already registered.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use nft_ prefix. By when I added chain types, I forgot to use the
nftables prefix. Rename enum nft_chain_type to enum nft_chain_types too,
otherwise there is an overlap.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
IPv4 was changed in commit 52a773d645 ("net: Export ip fragment
sysctl to unprivileged users")
The only sysctl that is not per-netns is not used :
ip6frag_secret_interval
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move call to call_fib6_entry_notifiers for new IPv6 routes to right
before the insertion into the FIB. At this point notifier handlers can
decide the fate of the new route with a clean path to delete the
potential new entry if the notifier returns non-0.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Steffen Klassert says:
====================
pull request (net-next): ipsec-next 2018-03-29
1) Remove a redundant pointer initialization esp_input_set_header().
From Colin Ian King.
2) Mark the xfrm kmem_caches as __ro_after_init.
From Alexey Dobriyan.
3) Do the checksum for an ipsec offlad packet in software
if the device does not advertise NETIF_F_HW_ESP_TX_CSUM.
From Shannon Nelson.
4) Use booleans for true and false instead of integers
in xfrm_policy_cache_flush().
From Gustavo A. R. Silva
Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Steffen Klassert says:
====================
pull request (net): ipsec 2018-03-29
1) Fix a rcu_read_lock/rcu_read_unlock imbalance
in the error path of xfrm_local_error().
From Taehee Yoo.
2) Some VTI MTU fixes. From Stefano Brivio.
3) Fix a too early overwritten skb control buffer
on xfrm transport mode.
Please note that this pull request has a merge conflict
in net/ipv4/ip_tunnel.c.
The conflict is between
commit f6cc9c054e ("ip_tunnel: Emit events for post-register MTU changes")
from the net tree and
commit 24fc79798b ("ip_tunnel: Clamp MTU to bounds on new link")
from the ipsec tree.
It can be solved as it is currently done in linux-next.
====================
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>
David S. Miller