When an IPv4 packet is received, the ip_rcv_core(...) sets the receiving
interface index into the IPv4 socket control block (v5.16-rc4,
net/ipv4/ip_input.c line 510):
IPCB(skb)->iif = skb->skb_iif;
If that IPv4 packet is meant to be encapsulated in an outer IPv6+SRH
header, the seg6_do_srh_encap(...) performs the required encapsulation.
In this case, the seg6_do_srh_encap function clears the IPv6 socket control
block (v5.16-rc4 net/ipv6/seg6_iptunnel.c line 163):
memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
The memset(...) was introduced in commit ef489749aa ("ipv6: sr: clear
IP6CB(skb) on SRH ip4ip6 encapsulation") a long time ago (2019-01-29).
Since the IPv6 socket control block and the IPv4 socket control block share
the same memory area (skb->cb), the receiving interface index info is lost
(IP6CB(skb)->iif is set to zero).
As a side effect, that condition triggers a NULL pointer dereference if
commit 0857d6f8c7 ("ipv6: When forwarding count rx stats on the orig
netdev") is applied.
To fix that issue, we set the IP6CB(skb)->iif with the index of the
receiving interface once again.
Fixes: ef489749aa ("ipv6: sr: clear IP6CB(skb) on SRH ip4ip6 encapsulation")
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20211208195409.12169-1-andrea.mayer@uniroma2.it
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The variable err is being initialized with a value that is never read, it
is being updated later on. The assignment is redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove all but the first include of net/lwtunnel.h from seg6_iptunnel.c.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Lv Ruyi <lv.ruyi@zte.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces netfilter hooks for solving the problem that
conntrack couldn't record both inner flows and outer flows.
This patch also introduces a new sysctl toggle for enabling lightweight
tunnel netfilter hooks.
Signed-off-by: Ryoga Saito <contact@proelbtn.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Refactor the function seg6_lwt_headroom out of the seg6_iptunnel.h uapi
header, because it is only used in seg6_iptunnel.c. Moreover, it is only
used in the kernel code, as indicated by the "#ifdef __KERNEL__".
Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Ioana-Ruxandra Stăncioi <stancioi@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The seg6_validate_srh() is used to validate SRH for three cases:
case1: SRH of data-plane SRv6 packets to be processed by the Linux kernel.
Case2: SRH of the netlink message received from user-space (iproute2)
Case3: SRH injected into packets through setsockopt
In case1, the SRH can be encoded in the Reduced way (i.e., first SID is
carried in DA only and not represented as SID in the SRH) and the
seg6_validate_srh() now handles this case correctly.
In case2 and case3, the SRH shouldn’t be encoded in the Reduced way
otherwise we lose the first segment (i.e., the first hop).
The current implementation of the seg6_validate_srh() allow SRH of case2
and case3 to be encoded in the Reduced way. This leads a slab-out-of-bounds
problem.
This patch verifies SRH of case1, case2 and case3. Allowing case1 to be
reduced while preventing SRH of case2 and case3 from being reduced .
Reported-by: syzbot+e8c028b62439eac42073@syzkaller.appspotmail.com
Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: 0cb7498f23 ("seg6: fix SRH processing to comply with RFC8754")
Signed-off-by: Ahmed Abdelsalam <ahabdels@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
The Internet Assigned Numbers Authority (IANA) has recently assigned
a protocol number value of 143 for Ethernet [1].
Before this assignment, encapsulation mechanisms such as Segment Routing
used the IPv6-NoNxt protocol number (59) to indicate that the encapsulated
payload is an Ethernet frame.
In this patch, we add the definition of the Ethernet protocol number to the
kernel headers and update the SRv6 L2 tunnels to use it.
[1] https://www.iana.org/assignments/protocol-numbers/protocol-numbers.xhtml
Signed-off-by: Paolo Lungaroni <paolo.lungaroni@cnit.it>
Reviewed-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Acked-by: Ahmed Abdelsalam <ahmed.abdelsalam@gssi.it>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We currently have two levels of strict validation:
1) liberal (default)
- undefined (type >= max) & NLA_UNSPEC attributes accepted
- attribute length >= expected accepted
- garbage at end of message accepted
2) strict (opt-in)
- NLA_UNSPEC attributes accepted
- attribute length >= expected accepted
Split out parsing strictness into four different options:
* TRAILING - check that there's no trailing data after parsing
attributes (in message or nested)
* MAXTYPE - reject attrs > max known type
* UNSPEC - reject attributes with NLA_UNSPEC policy entries
* STRICT_ATTRS - strictly validate attribute size
The default for future things should be *everything*.
The current *_strict() is a combination of TRAILING and MAXTYPE,
and is renamed to _deprecated_strict().
The current regular parsing has none of this, and is renamed to
*_parse_deprecated().
Additionally it allows us to selectively set one of the new flags
even on old policies. Notably, the UNSPEC flag could be useful in
this case, since it can be arranged (by filling in the policy) to
not be an incompatible userspace ABI change, but would then going
forward prevent forgetting attribute entries. Similar can apply
to the POLICY flag.
We end up with the following renames:
* nla_parse -> nla_parse_deprecated
* nla_parse_strict -> nla_parse_deprecated_strict
* nlmsg_parse -> nlmsg_parse_deprecated
* nlmsg_parse_strict -> nlmsg_parse_deprecated_strict
* nla_parse_nested -> nla_parse_nested_deprecated
* nla_validate_nested -> nla_validate_nested_deprecated
Using spatch, of course:
@@
expression TB, MAX, HEAD, LEN, POL, EXT;
@@
-nla_parse(TB, MAX, HEAD, LEN, POL, EXT)
+nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT)
@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT)
@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
@@
expression TB, MAX, NLA, POL, EXT;
@@
-nla_parse_nested(TB, MAX, NLA, POL, EXT)
+nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT)
@@
expression START, MAX, POL, EXT;
@@
-nla_validate_nested(START, MAX, POL, EXT)
+nla_validate_nested_deprecated(START, MAX, POL, EXT)
@@
expression NLH, HDRLEN, MAX, POL, EXT;
@@
-nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT)
+nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT)
For this patch, don't actually add the strict, non-renamed versions
yet so that it breaks compile if I get it wrong.
Also, while at it, make nla_validate and nla_parse go down to a
common __nla_validate_parse() function to avoid code duplication.
Ultimately, this allows us to have very strict validation for every
new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the
next patch, while existing things will continue to work as is.
In effect then, this adds fully strict validation for any new command.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb->cb may contain data from previous layers (in an observed case
IPv4 with L3 Master Device). In the observed scenario, the data in
IPCB(skb)->frags was misinterpreted as IP6CB(skb)->frag_max_size,
eventually caused an unexpected IPv6 fragmentation in ip6_fragment()
through ip6_finish_output().
This patch clears IP6CB(skb), which potentially contains garbage data,
on the SRH ip4ip6 encapsulation.
Fixes: 32d99d0b67 ("ipv6: sr: add support for ip4ip6 encapsulation")
Signed-off-by: Yohei Kanemaru <yohei.kanemaru@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In 'seg6_output', stack variable 'struct flowi6 fl6' was missing
initialization.
Fixes: 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The rol32 call is currently rotating hash but the rol'd value is
being discarded. I believe the current code is incorrect and hash
should be assigned the rotated value returned from rol32.
Detected by CoverityScan, CID#1468411 ("Useless call")
Fixes: b5facfdba1 ("ipv6: sr: Compute flowlabel for outer IPv6 header of seg6 encap mode")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: dlebrun@google.com
Signed-off-by: David S. Miller <davem@davemloft.net>
Filling in the padding slot in the bpf structure as a bug fix in 'ne'
overlapped with actually using that padding area for something in
'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
The seg6_make_flowlabel() is used by seg6_do_srh_encap() to compute the
flowlabel from a given skb. It relies on skb_get_hash() which eventually
calls __skb_flow_dissect() to extract the flow_keys struct values from
the skb.
In case of IPv4 traffic, calling seg6_make_flowlabel() after skb_push(),
skb_reset_network_header(), and skb_mac_header_rebuild() will results in
flow_keys struct of all key values set to zero.
This patch calls seg6_make_flowlabel() before resetting the headers of skb
to get the right key values.
Extracted Key values are based on the type inner packet as follows:
1) IPv6 traffic: src_IP, dst_IP, L4 proto, and flowlabel of inner packet.
2) IPv4 traffic: src_IP, dst_IP, L4 proto, src_port, and dst_port
3) L2 traffic: depends on what kind of traffic carried into the L2
frame. IPv6 and IPv4 traffic works as discussed 1) and 2)
Here a hex_dump of struct flow_keys for IPv4 and IPv6 traffic
10.100.1.100: 47302 > 30.0.0.2: 5001
00000000: 14 00 02 00 00 00 00 00 08 00 11 00 00 00 00 00
00000010: 00 00 00 00 00 00 00 00 13 89 b8 c6 1e 00 00 02
00000020: 0a 64 01 64
fc00:a1:a > b2::2
00000000: 28 00 03 00 00 00 00 00 86 dd 11 00 99 f9 02 00
00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 b2 00 00
00000020: 00 00 00 00 00 00 00 00 00 00 00 02 fc 00 00 a1
00000030: 00 00 00 00 00 00 00 00 00 00 00 0a
Signed-off-by: Ahmed Abdelsalam <amsalam20@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ECMP (equal-cost multipath) hashes are typically computed on the packets'
5-tuple(src IP, dst IP, src port, dst port, L4 proto).
For encapsulated packets, the L4 data is not readily available and ECMP
hashing will often revert to (src IP, dst IP). This will lead to traffic
polarization on a single ECMP path, causing congestion and waste of network
capacity.
In IPv6, the 20-bit flow label field is also used as part of the ECMP hash.
In the lack of L4 data, the hashing will be on (src IP, dst IP, flow
label). Having a non-zero flow label is thus important for proper traffic
load balancing when L4 data is unavailable (i.e., when packets are
encapsulated).
Currently, the seg6_do_srh_encap() function extracts the original packet's
flow label and set it as the outer IPv6 flow label. There are two issues
with this behaviour:
a) There is no guarantee that the inner flow label is set by the source.
b) If the original packet is not IPv6, the flow label will be set to
zero (e.g., IPv4 or L2 encap).
This patch adds a function, named seg6_make_flowlabel(), that computes a
flow label from a given skb. It supports IPv6, IPv4 and L2 payloads, and
leverages the per namespace 'seg6_flowlabel" sysctl value.
The currently support behaviours are as follows:
-1 set flowlabel to zero.
0 copy flowlabel from Inner paceket in case of Inner IPv6
(Set flowlabel to 0 in case IPv4/L2)
1 Compute the flowlabel using seg6_make_flowlabel()
This patch has been tested for IPv6, IPv4, and L2 traffic.
Signed-off-by: Ahmed Abdelsalam <amsalam20@gmail.com>
Acked-by: David Lebrun <dlebrun@google.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>
This patch implements the L2 frame encapsulation mechanism, referred to
as T.Encaps.L2 in the SRv6 specifications [1].
A new type of SRv6 tunnel mode is added (SEG6_IPTUN_MODE_L2ENCAP). It only
accepts packets with an existing MAC header (i.e., it will not work for
locally generated packets). The resulting packet looks like IPv6 -> SRH ->
Ethernet -> original L3 payload. The next header field of the SRH is set to
NEXTHDR_NONE.
[1] https://tools.ietf.org/html/draft-filsfils-spring-srv6-network-programming-01
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch enables the SRv6 encapsulation mode to carry an IPv4 payload.
All the infrastructure was already present, I just had to add a parameter
to seg6_do_srh_encap() to specify the inner packet protocol, and perform
some additional checks.
Usage example:
ip route add 1.2.3.4 encap seg6 mode encap segs fc00::1,fc00::2 dev eth0
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch exports the seg6_do_srh_encap() and seg6_do_srh_inline()
functions. It also removes the CONFIG_IPV6_SEG6_INLINE knob
that enabled the compilation of seg6_do_srh_inline(). This function
is now built-in.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass extack arg down to lwtunnel_build_state and the build_state callbacks.
Add messages for failures in lwtunnel_build_state, and add the extarg to
nla_parse where possible in the build_state callbacks.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When CONFIG_IPV6_SEG6_LWTUNNEL is selected, automatically select DST_CACHE.
This allows to remove multiple ifdefs.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
We already use dst_cache in seg6_output, when handling locally generated
packets. We extend it in seg6_input, to also handle forwarded packets, and avoid
unnecessary fib lookups.
Performances for SRH encapsulation before the patch:
Result: OK: 5656067(c5655678+d388) usec, 5000000 (1000byte,0frags)
884006pps 7072Mb/sec (7072048000bps) errors: 0
Performances after the patch:
Result: OK: 4774543(c4774084+d459) usec, 5000000 (1000byte,0frags)
1047220pps 8377Mb/sec (8377760000bps) errors: 0
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
To insert or encapsulate a packet with an SRH, we need a large enough skb
headroom. Currently, we are using pskb_expand_head to inconditionally increase
the size of the headroom by the amount needed by the SRH (and IPv6 header).
If this reallocation is performed by another CPU than the one that initially
allocated the skb, then when the initial CPU kfree the skb, it will enter the
__slab_free slowpath, impacting performances.
This patch replaces pskb_expand_head with skb_cow_head, that will reallocate the
skb head only if the headroom is not large enough.
Performances for SRH encapsulation before the patch:
Result: OK: 7348320(c7347271+d1048) usec, 5000000 (1000byte,0frags)
680427pps 5443Mb/sec (5443416000bps) errors: 0
Performances after the patch:
Result: OK: 5656067(c5655678+d388) usec, 5000000 (1000byte,0frags)
884006pps 7072Mb/sec (7072048000bps) errors: 0
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes the following sparse warnings:
net/ipv6/seg6_iptunnel.c:58:5: warning:
symbol 'nla_put_srh' was not declared. Should it be static?
net/ipv6/seg6_iptunnel.c:238:5: warning:
symbol 'seg6_input' was not declared. Should it be static?
net/ipv6/seg6_iptunnel.c:254:5: warning:
symbol 'seg6_output' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Nothing about lwt state requires a device reference, so remove the
input argument.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Modules implementing lwtunnel ops should not be allowed to unload
while there is state alive using those ops, so specify the owning
module for all lwtunnel ops.
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch enables the verification of the HMAC signature for transiting
SR-enabled packets, and its insertion on encapsulated/injected SRH.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch creates a new type of interfaceless lightweight tunnel (SEG6),
enabling the encapsulation and injection of SRH within locally emitted
packets and forwarded packets.
>From a configuration viewpoint, a seg6 tunnel would be configured as follows:
ip -6 ro ad fc00::1/128 encap seg6 mode encap segs fc42::1,fc42::2,fc42::3 dev eth0
Any packet whose destination address is fc00::1 would thus be encapsulated
within an outer IPv6 header containing the SRH with three segments, and would
actually be routed to the first segment of the list. If `mode inline' was
specified instead of `mode encap', then the SRH would be directly inserted
after the IPv6 header without outer encapsulation.
The inline mode is only available if CONFIG_IPV6_SEG6_INLINE is enabled. This
feature was made configurable because direct header insertion may break
several mechanisms such as PMTUD or IPSec AH.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
