Pass a sockptr_t to prepare for set_fs-less handling of the kernel
pointer from bpf-cgroup.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass a sockptr_t to prepare for set_fs-less handling of the kernel
pointer from bpf-cgroup.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-07-21
The following pull-request contains BPF updates for your *net-next* tree.
We've added 46 non-merge commits during the last 6 day(s) which contain
a total of 68 files changed, 4929 insertions(+), 526 deletions(-).
The main changes are:
1) Run BPF program on socket lookup, from Jakub.
2) Introduce cpumap, from Lorenzo.
3) s390 JIT fixes, from Ilya.
4) teach riscv JIT to emit compressed insns, from Luke.
5) use build time computed BTF ids in bpf iter, from Yonghong.
====================
Purely independent overlapping changes in both filter.h and xdp.h
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
Add setsockopt SOL_IP/IP_RECVERR_4884 to return the offset to an
extension struct if present.
ICMP messages may include an extension structure after the original
datagram. RFC 4884 standardized this behavior. It stores the offset
in words to the extension header in u8 icmphdr.un.reserved[1].
The field is valid only for ICMP types destination unreachable, time
exceeded and parameter problem, if length is at least 128 bytes and
entire packet does not exceed 576 bytes.
Return the offset to the start of the extension struct when reading an
ICMP error from the error queue, if it matches the above constraints.
Do not return the raw u8 field. Return the offset from the start of
the user buffer, in bytes. The kernel does not return the network and
transport headers, so subtract those.
Also validate the headers. Return the offset regardless of validation,
as an invalid extension must still not be misinterpreted as part of
the original datagram. Note that !invalid does not imply valid. If
the extension version does not match, no validation can take place,
for instance.
For backward compatibility, make this optional, set by setsockopt
SOL_IP/IP_RECVERR_RFC4884. For API example and feature test, see
github.com/wdebruij/kerneltools/blob/master/tests/recv_icmp_v2.c
For forward compatibility, reserve only setsockopt value 1, leaving
other bits for additional icmp extensions.
Changes
v1->v2:
- convert word offset to byte offset from start of user buffer
- return in ee_data as u8 may be insufficient
- define extension struct and object header structs
- return len only if constraints met
- if returning len, also validate
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Handle the few cases that need special treatment in-line using
in_compat_syscall(). This also removes all the now unused
compat_{get,set}sockopt methods.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Handle the few cases that need special treatment in-line using
in_compat_syscall().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Factor out one helper each for setting the native and compat
version of the MCAST_MSFILTER option.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Factor out one helper each for setting the native and compat
version of the MCAST_MSFILTER option.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Factor out one helper each for getting the native and compat
version of the MCAST_MSFILTER option.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lift the in_compat_syscall() from the callers instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
All instances handle compat sockopts via in_compat_syscall() now, so
remove the compat_{get,set} methods as well as the
compat_nf_{get,set}sockopt wrappers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge the native and compat {get,set}sockopt handlers using
in_compat_syscall().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge the native and compat {get,set}sockopt handlers using
in_compat_syscall().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the compat handling to sock_common_{get,set}sockopt instead,
keyed of in_compat_syscall(). This allow to remove the now unused
->compat_{get,set}sockopt methods from struct proto_ops.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Following INET/TCP socket lookup changes, modify UDP socket lookup to let
BPF program select a receiving socket before searching for a socket by
destination address and port as usual.
Lookup of connected sockets that match packet 4-tuple is unaffected by this
change. BPF program runs, and potentially overrides the lookup result, only
if a 4-tuple match was not found.
Suggested-by: Marek Majkowski <marek@cloudflare.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200717103536.397595-9-jakub@cloudflare.com
Prepare for calling into reuseport from __udp4_lib_lookup as well.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200717103536.397595-8-jakub@cloudflare.com
Run a BPF program before looking up a listening socket on the receive path.
Program selects a listening socket to yield as result of socket lookup by
calling bpf_sk_assign() helper and returning SK_PASS code. Program can
revert its decision by assigning a NULL socket with bpf_sk_assign().
Alternatively, BPF program can also fail the lookup by returning with
SK_DROP, or let the lookup continue as usual with SK_PASS on return, when
no socket has been selected with bpf_sk_assign().
This lets the user match packets with listening sockets freely at the last
possible point on the receive path, where we know that packets are destined
for local delivery after undergoing policing, filtering, and routing.
With BPF code selecting the socket, directing packets destined to an IP
range or to a port range to a single socket becomes possible.
In case multiple programs are attached, they are run in series in the order
in which they were attached. The end result is determined from return codes
of all the programs according to following rules:
1. If any program returned SK_PASS and selected a valid socket, the socket
is used as result of socket lookup.
2. If more than one program returned SK_PASS and selected a socket,
last selection takes effect.
3. If any program returned SK_DROP, and no program returned SK_PASS and
selected a socket, socket lookup fails with -ECONNREFUSED.
4. If all programs returned SK_PASS and none of them selected a socket,
socket lookup continues to htable-based lookup.
Suggested-by: Marek Majkowski <marek@cloudflare.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200717103536.397595-5-jakub@cloudflare.com
Prepare for calling into reuseport from __inet_lookup_listener as well.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200717103536.397595-4-jakub@cloudflare.com
There are two existing SNMP counters, TCPDSACKRecv and TCPDSACKOfoRecv,
which are incremented depending on whether the DSACKed range is below
the cumulative ACK sequence number or not. Unfortunately, these both
implicitly assume each DSACK covers only one segment. This makes these
counters unusable for estimating spurious retransmit rates,
or real/non-spurious loss rate.
This patch introduces a new SNMP counter, TCPDSACKRecvSegs, which tracks
the estimated number of duplicate segments based on:
(DSACKed sequence range) / MSS. This counter is usable for estimating
spurious retransmit rates, or real/non-spurious loss rate.
Signed-off-by: Priyaranjan Jha <priyarjha@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, while processing DSACK, we assume DSACK covers only one
segment. This leads to significant underestimation of DSACKs with
LRO/GRO. This patch fixes segment accounting with DSACK by estimating
segment count from DSACK sequence range / MSS.
Signed-off-by: Priyaranjan Jha <priyarjha@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yousuk Seung <ysseung@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-07-13
The following pull-request contains BPF updates for your *net-next* tree.
We've added 36 non-merge commits during the last 7 day(s) which contain
a total of 62 files changed, 2242 insertions(+), 468 deletions(-).
The main changes are:
1) Avoid trace_printk warning banner by switching bpf_trace_printk to use
its own tracing event, from Alan.
2) Better libbpf support on older kernels, from Andrii.
3) Additional AF_XDP stats, from Ciara.
4) build time resolution of BTF IDs, from Jiri.
5) BPF_CGROUP_INET_SOCK_RELEASE hook, from Stanislav.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Simple fixes which require no deep knowledge of the code.
Cc: Paul Moore <paul@paul-moore.com>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 0c3d79bce4 ("tcp: reduce SYN-ACK
retrans for TCP_DEFER_ACCEPT") introduces syn_ack_recalc() which decides
if a minisock is held and a SYN+ACK is retransmitted or not.
If rskq_defer_accept is not zero in syn_ack_recalc(), max_retries always
has the same value because max_retries is overwritten by rskq_defer_accept
in reqsk_timer_handler().
This commit adds three changes:
- remove redundant non-zero check for rskq_defer_accept in
reqsk_timer_handler().
- remove max_retries from the arguments of syn_ack_recalc() and use
rskq_defer_accept instead.
- rename thresh to max_syn_ack_retries for readability.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Reviewed-by: Benjamin Herrenschmidt <benh@amazon.com>
CC: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add an interface to report offloaded UDP ports via ethtool netlink.
Now that core takes care of tracking which UDP tunnel ports the NICs
are aware of we can quite easily export this information out to
user space.
The responsibility of writing the netlink dumps is split between
ethtool code and udp_tunnel_nic.c - since udp_tunnel module may
not always be loaded, yet we should always report the capabilities
of the NIC.
$ ethtool --show-tunnels eth0
Tunnel information for eth0:
UDP port table 0:
Size: 4
Types: vxlan
No entries
UDP port table 1:
Size: 4
Types: geneve, vxlan-gpe
Entries (1):
port 1230, vxlan-gpe
v4:
- back to v2, build fix is now directly in udp_tunnel.h
v3:
- don't compile ETHTOOL_MSG_TUNNEL_INFO_GET in if CONFIG_INET
not set.
v2:
- fix string set count,
- reorder enums in the uAPI,
- fix type of ETHTOOL_A_TUNNEL_UDP_TABLE_TYPES to bitset
in docs and comments.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cater to devices which:
(a) may want to sleep in the callbacks;
(b) only have IPv4 support;
(c) need all the programming to happen while the netdev is up.
Drivers attach UDP tunnel offload info struct to their netdevs,
where they declare how many UDP ports of various tunnel types
they support. Core takes care of tracking which ports to offload.
Use a fixed-size array since this matches what almost all drivers
do, and avoids a complexity and uncertainty around memory allocations
in an atomic context.
Make sure that tunnel drivers don't try to replay the ports when
new NIC netdev is registered. Automatic replays would mess up
reference counting, and will be removed completely once all drivers
are converted.
v4:
- use a #define NULL to avoid build issues with CONFIG_INET=n.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit bf9765145b ("sock: Make sk_protocol a 16-bit value")
the current size of 'sdiag_protocol' is not sufficient to represent
the possible protocol values.
This change introduces a new inet diag request attribute to let
user space specify the relevant protocol number using u32 values.
The attribute is parsed by inet diag core on get/dump command
and the extended protocol value, if available, is preferred to
'sdiag_protocol' to lookup the diag handler.
The parse attributed are exposed to all the diag handlers via
the cb->data.
Note that inet_diag_dump_one_icsk() is left unmodified, as it
will not be used by protocol using the extended attribute.
Suggested-by: David S. Miller <davem@davemloft.net>
Co-developed-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
Acked-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@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 updates for net-next:
1) Support for rejecting packets from the prerouting chain, from
Laura Garcia Liebana.
2) Remove useless assignment in pipapo, from Stefano Brivio.
3) On demand hook registration in IPVS, from Julian Anastasov.
4) Expire IPVS connection from process context to not overload
timers, also from Julian.
5) Fallback to conntrack TCP tracker to handle connection reuse
in IPVS, from Julian Anastasov.
6) Several patches to support for chain bindings.
7) Expose enum nft_chain_flags through UAPI.
8) Reject unsupported chain flags from the netlink control plane.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Sometimes it's handy to know when the socket gets freed. In
particular, we'd like to try to use a smarter allocation of
ports for bpf_bind and explore the possibility of limiting
the number of SOCK_DGRAM sockets the process can have.
Implement BPF_CGROUP_INET_SOCK_RELEASE hook that triggers on
inet socket release. It triggers only for userspace sockets
(not in-kernel ones) and therefore has the same semantics as
the existing BPF_CGROUP_INET_SOCK_CREATE.
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200706230128.4073544-2-sdf@google.com
IPv4 ping sockets don't set fl4.fl4_icmp_{type,code}, which leads to
incomplete IPsec ACQUIRE messages being sent to userspace. Currently,
both raw sockets and IPv6 ping sockets set those fields.
Expected output of "ip xfrm monitor":
acquire proto esp
sel src 10.0.2.15/32 dst 8.8.8.8/32 proto icmp type 8 code 0 dev ens4
policy src 10.0.2.15/32 dst 8.8.8.8/32
<snip>
Currently with ping sockets:
acquire proto esp
sel src 10.0.2.15/32 dst 8.8.8.8/32 proto icmp type 0 code 0 dev ens4
policy src 10.0.2.15/32 dst 8.8.8.8/32
<snip>
The Libreswan test suite found this problem after Fedora changed the
value for the sysctl net.ipv4.ping_group_range.
Fixes: c319b4d76b ("net: ipv4: add IPPROTO_ICMP socket kind")
Reported-by: Paul Wouters <pwouters@redhat.com>
Tested-by: Paul Wouters <pwouters@redhat.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-07-04
The following pull-request contains BPF updates for your *net-next* tree.
We've added 73 non-merge commits during the last 17 day(s) which contain
a total of 106 files changed, 5233 insertions(+), 1283 deletions(-).
The main changes are:
1) bpftool ability to show PIDs of processes having open file descriptors
for BPF map/program/link/BTF objects, relying on BPF iterator progs
to extract this info efficiently, from Andrii Nakryiko.
2) Addition of BPF iterator progs for dumping TCP and UDP sockets to
seq_files, from Yonghong Song.
3) Support access to BPF map fields in struct bpf_map from programs
through BTF struct access, from Andrey Ignatov.
4) Add a bpf_get_task_stack() helper to be able to dump /proc/*/stack
via seq_file from BPF iterator progs, from Song Liu.
5) Make SO_KEEPALIVE and related options available to bpf_setsockopt()
helper, from Dmitry Yakunin.
6) Optimize BPF sk_storage selection of its caching index, from Martin
KaFai Lau.
7) Removal of redundant synchronize_rcu()s from BPF map destruction which
has been a historic leftover, from Alexei Starovoitov.
8) Several improvements to test_progs to make it easier to create a shell
loop that invokes each test individually which is useful for some CIs,
from Jesper Dangaard Brouer.
9) Fix bpftool prog dump segfault when compiled without skeleton code on
older clang versions, from John Fastabend.
10) Bunch of cleanups and minor improvements, from various others.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Use struct pid instead of user space pid values that are prone to wrap
araound.
In addition track the entire thread group instead of just the first
thread that is started by exec. There are no multi-threaded user mode
drivers today but there is nothing preclucing user drivers from being
multi-threaded, so it is just a good idea to track the entire process.
Take a reference count on the tgid's in question to make it possible
to remove exit_umh in a future change.
As a struct pid is available directly use kill_pid_info.
The prior process signalling code was iffy in using a userspace pid
known to be in the initial pid namespace and then looking up it's task
in whatever the current pid namespace is. It worked only because
kernel threads always run in the initial pid namespace.
As the tgid is now refcounted verify the tgid is NULL at the start of
fork_usermode_driver to avoid the possibility of silent pid leaks.
v1: https://lkml.kernel.org/r/87mu4qdlv2.fsf_-_@x220.int.ebiederm.org
v2: https://lkml.kernel.org/r/a70l4oy8.fsf_-_@x220.int.ebiederm.org
Link: https://lkml.kernel.org/r/20200702164140.4468-12-ebiederm@xmission.com
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This essentially reverts commit 7212303268 ("tcp: md5: reject TCP_MD5SIG
or TCP_MD5SIG_EXT on established sockets")
Mathieu reported that many vendors BGP implementations can
actually switch TCP MD5 on established flows.
Quoting Mathieu :
Here is a list of a few network vendors along with their behavior
with respect to TCP MD5:
- Cisco: Allows for password to be changed, but within the hold-down
timer (~180 seconds).
- Juniper: When password is initially set on active connection it will
reset, but after that any subsequent password changes no network
resets.
- Nokia: No notes on if they flap the tcp connection or not.
- Ericsson/RedBack: Allows for 2 password (old/new) to co-exist until
both sides are ok with new passwords.
- Meta-Switch: Expects the password to be set before a connection is
attempted, but no further info on whether they reset the TCP
connection on a change.
- Avaya: Disable the neighbor, then set password, then re-enable.
- Zebos: Would normally allow the change when socket connected.
We can revert my prior change because commit 9424e2e7ad ("tcp: md5: fix potential
overestimation of TCP option space") removed the leak of 4 kernel bytes to
the wire that was the main reason for my patch.
While doing my investigations, I found a bug when a MD5 key is changed, leading
to these commits that stable teams want to consider before backporting this revert :
Commit 6a2febec33 ("tcp: md5: add missing memory barriers in tcp_md5_do_add()/tcp_md5_hash_key()")
Commit e6ced831ef ("tcp: md5: refine tcp_md5_do_add()/tcp_md5_hash_key() barriers")
Fixes: 7212303268 "tcp: md5: reject TCP_MD5SIG or TCP_MD5SIG_EXT on established sockets"
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Whenever tcp_try_rmem_schedule() returns an error, we are under
trouble and should make sure to wakeup readers so that they
can drain socket queues and eventually make room.
Fixes: 03f45c883c ("tcp: avoid extra wakeups for SO_RCVLOWAT users")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When no full socket is available, skbs are sent over a per-netns
control socket. Its sk_mark is temporarily adjusted to match that
of the real (request or timewait) socket or to reflect an incoming
skb, so that the outgoing skb inherits this in __ip_make_skb.
Introduction of the socket cookie mark field broke this. Now the
skb is set through the cookie and cork:
<caller> # init sockc.mark from sk_mark or cmsg
ip_append_data
ip_setup_cork # convert sockc.mark to cork mark
ip_push_pending_frames
ip_finish_skb
__ip_make_skb # set skb->mark to cork mark
But I missed these special control sockets. Update all callers of
__ip(6)_make_skb that were originally missed.
For IPv6, the same two icmp(v6) paths are affected. The third
case is not, as commit 92e55f412c ("tcp: don't annotate
mark on control socket from tcp_v6_send_response()") replaced
the ctl_sk->sk_mark with passing the mark field directly as a
function argument. That commit predates the commit that
introduced the bug.
Fixes: c6af0c227a ("ip: support SO_MARK cmsg")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reported-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Whenever cookie_init_timestamp() has been used to encode
ECN,SACK,WSCALE options, we can not remove the TS option in the SYNACK.
Otherwise, tcp_synack_options() will still advertize options like WSCALE
that we can not deduce later when receiving the packet from the client
to complete 3WHS.
Note that modern linux TCP stacks wont use MD5+TS+SACK in a SYN packet,
but we can not know for sure that all TCP stacks have the same logic.
Before the fix a tcpdump would exhibit this wrong exchange :
10:12:15.464591 IP C > S: Flags [S], seq 4202415601, win 65535, options [nop,nop,md5 valid,mss 1400,sackOK,TS val 456965269 ecr 0,nop,wscale 8], length 0
10:12:15.464602 IP S > C: Flags [S.], seq 253516766, ack 4202415602, win 65535, options [nop,nop,md5 valid,mss 1400,nop,nop,sackOK,nop,wscale 8], length 0
10:12:15.464611 IP C > S: Flags [.], ack 1, win 256, options [nop,nop,md5 valid], length 0
10:12:15.464678 IP C > S: Flags [P.], seq 1:13, ack 1, win 256, options [nop,nop,md5 valid], length 12
10:12:15.464685 IP S > C: Flags [.], ack 13, win 65535, options [nop,nop,md5 valid], length 0
After this patch the exchange looks saner :
11:59:59.882990 IP C > S: Flags [S], seq 517075944, win 65535, options [nop,nop,md5 valid,mss 1400,sackOK,TS val 1751508483 ecr 0,nop,wscale 8], length 0
11:59:59.883002 IP S > C: Flags [S.], seq 1902939253, ack 517075945, win 65535, options [nop,nop,md5 valid,mss 1400,sackOK,TS val 1751508479 ecr 1751508483,nop,wscale 8], length 0
11:59:59.883012 IP C > S: Flags [.], ack 1, win 256, options [nop,nop,md5 valid,nop,nop,TS val 1751508483 ecr 1751508479], length 0
11:59:59.883114 IP C > S: Flags [P.], seq 1:13, ack 1, win 256, options [nop,nop,md5 valid,nop,nop,TS val 1751508483 ecr 1751508479], length 12
11:59:59.883122 IP S > C: Flags [.], ack 13, win 256, options [nop,nop,md5 valid,nop,nop,TS val 1751508483 ecr 1751508483], length 0
11:59:59.883152 IP S > C: Flags [P.], seq 1:13, ack 13, win 256, options [nop,nop,md5 valid,nop,nop,TS val 1751508484 ecr 1751508483], length 12
11:59:59.883170 IP C > S: Flags [.], ack 13, win 256, options [nop,nop,md5 valid,nop,nop,TS val 1751508484 ecr 1751508484], length 0
Of course, no SACK block will ever be added later, but nothing should break.
Technically, we could remove the 4 nops included in MD5+TS options,
but again some stacks could break seeing not conventional alignment.
Fixes: 4957faade1 ("TCPCT part 1g: Responder Cookie => Initiator")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
My prior fix went a bit too far, according to Herbert and Mathieu.
Since we accept that concurrent TCP MD5 lookups might see inconsistent
keys, we can use READ_ONCE()/WRITE_ONCE() instead of smp_rmb()/smp_wmb()
Clearing all key->key[] is needed to avoid possible KMSAN reports,
if key->keylen is increased. Since tcp_md5_do_add() is not fast path,
using __GFP_ZERO to clear all struct tcp_md5sig_key is simpler.
data_race() was added in linux-5.8 and will prevent KCSAN reports,
this can safely be removed in stable backports, if data_race() is
not yet backported.
v2: use data_race() both in tcp_md5_hash_key() and tcp_md5_do_add()
Fixes: 6a2febec33 ("tcp: md5: add missing memory barriers in tcp_md5_do_add()/tcp_md5_hash_key()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Marco Elver <elver@google.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
MD5 keys are read with RCU protection, and tcp_md5_do_add()
might update in-place a prior key.
Normally, typical RCU updates would allocate a new piece
of memory. In this case only key->key and key->keylen might
be updated, and we do not care if an incoming packet could
see the old key, the new one, or some intermediate value,
since changing the key on a live flow is known to be problematic
anyway.
We only want to make sure that in the case key->keylen
is changed, cpus in tcp_md5_hash_key() wont try to use
uninitialized data, or crash because key->keylen was
read twice to feed sg_init_one() and ahash_request_set_crypt()
Fixes: 9ea88a1530 ("tcp: md5: check md5 signature without socket lock")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When skb is coalesced tcp_ack_tstamp() still needs to be called when not
fully acked in tcp_clean_rtx_queue(), otherwise SCM_TSTAMP_ACK
timestamps may never be fired. Since the original patch series had
dependent commits, this patch fixes the issue instead of reverting by
restoring calls to tcp_ack_tstamp() when skb is not fully acked.
Fixes: fdb7eb21dd ("tcp: stamp SCM_TSTAMP_ACK later in tcp_clean_rtx_queue()")
Signed-off-by: Yousuk Seung <ysseung@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vti uses skb->protocol to determine packet type, and bails out if it's
not set. For AF_PACKET injection, we need to support its call chain of:
packet_sendmsg -> packet_snd -> packet_parse_headers ->
dev_parse_header_protocol -> parse_protocol
Without a valid parse_protocol, this returns zero, and vti rejects the
skb. So, this wires up the ip_tunnel handler for layer 3 packets for
that case.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ipip uses skb->protocol to determine packet type, and bails out if it's
not set. For AF_PACKET injection, we need to support its call chain of:
packet_sendmsg -> packet_snd -> packet_parse_headers ->
dev_parse_header_protocol -> parse_protocol
Without a valid parse_protocol, this returns zero, and ipip rejects the
skb. So, this wires up the ip_tunnel handler for layer 3 packets for
that case.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some devices that take straight up layer 3 packets benefit from having a
shared header_ops so that AF_PACKET sockets can inject packets that are
recognized. This shared infrastructure will be used by other drivers
that currently can't inject packets using AF_PACKET. It also exposes the
parser function, as it is useful in standalone form too.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
REJECT statement can be only used in INPUT, FORWARD and OUTPUT
chains. This patch adds support of REJECT, both icmp and tcp
reset, at PREROUTING stage.
The need for this patch comes from the requirement of some
forwarding devices to reject traffic before the natting and
routing decisions.
The main use case is to be able to send a graceful termination
to legitimate clients that, under any circumstances, the NATed
endpoints are not available. This option allows clients to
decide either to perform a reconnection or manage the error in
their side, instead of just dropping the connection and let
them die due to timeout.
It is supported ipv4, ipv6 and inet families for nft
infrastructure.
Signed-off-by: Laura Garcia Liebana <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
