This is a cleanup patch, making code a bit more concise.
1) Use skb_network_offset(skb) in place of
(skb_network_header(skb) - skb->data)
2) Use -skb_network_offset(skb) in place of
(skb->data - skb_network_header(skb))
3) Use skb_transport_offset(skb) in place of
(skb_transport_header(skb) - skb->data)
4) Use skb_inner_transport_offset(skb) in place of
(skb_inner_transport_header(skb) - skb->data)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Edward Cree <ecree.xilinx@gmail.com> # for sfc
Signed-off-by: David S. Miller <davem@davemloft.net>
If we're processing an IOAM Pre-allocated Trace Option-Type (the only
one supported currently), then send the trace as an ioam6 event to the
netlink multicast group. This way, user space apps will be able to
collect IOAM data.
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
ioam6_fill_trace_data() writes inside the skb payload without ensuring
it's writeable (e.g., not cloned). This function is called both from the
input and output path. The output path (ioam6_iptunnel) already does the
check. This commit provides a fix for the input path, inside
ipv6_hop_ioam(). It also updates ip6_parse_tlv() to refresh the network
header pointer ("nh") when returning from ipv6_hop_ioam().
Fixes: 9ee11f0fff ("ipv6: ioam: Data plane support for Pre-allocated Trace")
Reported-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Get a coccinelle warning as follows:
net/ipv6/exthdrs.c:800:29-30: WARNING opportunity for swap()
Use swap() to replace opencoded implementation.
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230807020947.1991716-1-william.xuanziyang@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
RPL code has a pattern where skb_dst_drop() is called before
ip6_route_input().
However, ip6_route_input() calls skb_dst_drop() internally,
so we need not call skb_dst_drop() before ip6_route_input().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230710213511.5364-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ipv6_destopt_rcv() and ipv6_parse_hopopts() pulls these data
- Hop-by-Hop/Destination Options Header : 8
- Hdr Ext Len : skb_transport_header(skb)[1] << 3
and calls ip6_parse_tlv(), so it need not check if skb_headlen() is less
than skb_transport_offset(skb) + (skb_transport_header(skb)[1] << 3).
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We need not reload hdr in ipv6_srh_rcv() unless we call
pskb_expand_head().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ipv6_rthdr_rcv() pulls these data
- Segment Routing Header : 8
- Hdr Ext Len : skb_transport_header(skb)[1] << 3
needed by ipv6_srh_rcv(), so pskb_pull() in ipv6_srh_rcv() never
fails and can be replaced with skb_pull().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ipv6_rpl_srh_rcv() checks if ipv6_hdr(skb)->daddr or ohdr->rpl_segaddr[i]
is the multicast address with ipv6_addr_type().
We have the same check for ipv6_hdr(skb)->daddr in ipv6_rthdr_rcv(), so we
need not recheck it in ipv6_rpl_srh_rcv().
Also, we should use ipv6_addr_is_multicast() for ohdr->rpl_segaddr[i]
instead of ipv6_addr_type().
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As Eric Dumazet pointed out [0], ipv6_rthdr_rcv() pulls these data
- Segment Routing Header : 8
- Hdr Ext Len : skb_transport_header(skb)[1] << 3
needed by ipv6_rpl_srh_rcv(). We can remove pskb_may_pull() and
replace pskb_pull() with skb_pull() in ipv6_rpl_srh_rcv().
Link: https://lore.kernel.org/netdev/CANn89iLboLwLrHXeHJucAqBkEL_S0rJFog68t7wwwXO-aNf5Mg@mail.gmail.com/ [0]
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cross-merge networking fixes after downstream PR.
Conflicts:
net/sched/sch_taprio.c
d636fc5dd6 ("net: sched: add rcu annotations around qdisc->qdisc_sleeping")
dced11ef84 ("net/sched: taprio: don't overwrite "sch" variable in taprio_dump_class_stats()")
net/ipv4/sysctl_net_ipv4.c
e209fee411 ("net/ipv4: ping_group_range: allow GID from 2147483648 to 4294967294")
ccce324dab ("tcp: make the first N SYN RTO backoffs linear")
https://lore.kernel.org/all/20230605100816.08d41a7b@canb.auug.org.au/
No adjacent changes.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A remote DoS vulnerability of RPL Source Routing is assigned CVE-2023-2156.
The Source Routing Header (SRH) has the following format:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Next Header | Hdr Ext Len | Routing Type | Segments Left |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| CmprI | CmprE | Pad | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Addresses[1..n] .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The originator of an SRH places the first hop's IPv6 address in the IPv6
header's IPv6 Destination Address and the second hop's IPv6 address as
the first address in Addresses[1..n].
The CmprI and CmprE fields indicate the number of prefix octets that are
shared with the IPv6 Destination Address. When CmprI or CmprE is not 0,
Addresses[1..n] are compressed as follows:
1..n-1 : (16 - CmprI) bytes
n : (16 - CmprE) bytes
Segments Left indicates the number of route segments remaining. When the
value is not zero, the SRH is forwarded to the next hop. Its address
is extracted from Addresses[n - Segment Left + 1] and swapped with IPv6
Destination Address.
When Segment Left is greater than or equal to 2, the size of SRH is not
changed because Addresses[1..n-1] are decompressed and recompressed with
CmprI.
OTOH, when Segment Left changes from 1 to 0, the new SRH could have a
different size because Addresses[1..n-1] are decompressed with CmprI and
recompressed with CmprE.
Let's say CmprI is 15 and CmprE is 0. When we receive SRH with Segment
Left >= 2, Addresses[1..n-1] have 1 byte for each, and Addresses[n] has
16 bytes. When Segment Left is 1, Addresses[1..n-1] is decompressed to
16 bytes and not recompressed. Finally, the new SRH will need more room
in the header, and the size is (16 - 1) * (n - 1) bytes.
Here the max value of n is 255 as Segment Left is u8, so in the worst case,
we have to allocate 3825 bytes in the skb headroom. However, now we only
allocate a small fixed buffer that is IPV6_RPL_SRH_WORST_SWAP_SIZE (16 + 7
bytes). If the decompressed size overflows the room, skb_push() hits BUG()
below [0].
Instead of allocating the fixed buffer for every packet, let's allocate
enough headroom only when we receive SRH with Segment Left 1.
[0]:
skbuff: skb_under_panic: text:ffffffff81c9f6e2 len:576 put:576 head:ffff8880070b5180 data:ffff8880070b4fb0 tail:0x70 end:0x140 dev:lo
kernel BUG at net/core/skbuff.c:200!
invalid opcode: 0000 [#1] PREEMPT SMP PTI
CPU: 0 PID: 154 Comm: python3 Not tainted 6.4.0-rc4-00190-gc308e9ec0047 #7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:skb_panic (net/core/skbuff.c:200)
Code: 4f 70 50 8b 87 bc 00 00 00 50 8b 87 b8 00 00 00 50 ff b7 c8 00 00 00 4c 8b 8f c0 00 00 00 48 c7 c7 80 6e 77 82 e8 ad 8b 60 ff <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000003da0 EFLAGS: 00000246
RAX: 0000000000000085 RBX: ffff8880058a6600 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff88807dc1c540 RDI: ffff88807dc1c540
RBP: ffffc90000003e48 R08: ffffffff82b392c8 R09: 00000000ffffdfff
R10: ffffffff82a592e0 R11: ffffffff82b092e0 R12: ffff888005b1c800
R13: ffff8880070b51b8 R14: ffff888005b1ca18 R15: ffff8880070b5190
FS: 00007f4539f0b740(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055670baf3000 CR3: 0000000005b0e000 CR4: 00000000007506f0
PKRU: 55555554
Call Trace:
<IRQ>
skb_push (net/core/skbuff.c:210)
ipv6_rthdr_rcv (./include/linux/skbuff.h:2880 net/ipv6/exthdrs.c:634 net/ipv6/exthdrs.c:718)
ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:437 (discriminator 5))
ip6_input_finish (./include/linux/rcupdate.h:805 net/ipv6/ip6_input.c:483)
__netif_receive_skb_one_core (net/core/dev.c:5494)
process_backlog (./include/linux/rcupdate.h:805 net/core/dev.c:5934)
__napi_poll (net/core/dev.c:6496)
net_rx_action (net/core/dev.c:6565 net/core/dev.c:6696)
__do_softirq (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/irq.h:142 kernel/softirq.c:572)
do_softirq (kernel/softirq.c:472 kernel/softirq.c:459)
</IRQ>
<TASK>
__local_bh_enable_ip (kernel/softirq.c:396)
__dev_queue_xmit (net/core/dev.c:4272)
ip6_finish_output2 (./include/net/neighbour.h:544 net/ipv6/ip6_output.c:134)
rawv6_sendmsg (./include/net/dst.h:458 ./include/linux/netfilter.h:303 net/ipv6/raw.c:656 net/ipv6/raw.c:914)
sock_sendmsg (net/socket.c:724 net/socket.c:747)
__sys_sendto (net/socket.c:2144)
__x64_sys_sendto (net/socket.c:2156 net/socket.c:2152 net/socket.c:2152)
do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
RIP: 0033:0x7f453a138aea
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 7e c3 0f 1f 44 00 00 41 54 48 83 ec 30 44 89
RSP: 002b:00007ffcc212a1c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007ffcc212a288 RCX: 00007f453a138aea
RDX: 0000000000000060 RSI: 00007f4539084c20 RDI: 0000000000000003
RBP: 00007f4538308e80 R08: 00007ffcc212a300 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: ffffffffc4653600 R14: 0000000000000001 R15: 00007f4539712d1b
</TASK>
Modules linked in:
Fixes: 8610c7c6e3 ("net: ipv6: add support for rpl sr exthdr")
Reported-by: Max VA
Closes: https://www.interruptlabs.co.uk/articles/linux-ipv6-route-of-death
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230605180617.67284-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In processing IPv6 segment routing header (SRH), several functions call
skb_dst_drop before ip6_route_input. However, ip6_route_input calls
skb_dst_drop within it, so there is no need to call skb_dst_drop in advance.
Signed-off-by: Yuya Tajima <yuya.tajimaa@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace kfree_skb() used in TLV encoded option header parsing with
kfree_skb_reason(). Following functions are involved:
ip6_parse_tlv()
ipv6_hop_ra()
ipv6_hop_ioam()
ipv6_hop_jumbo()
ipv6_hop_calipso()
ipv6_dest_hao()
Most skb drops during this process are regarded as 'InHdrErrors',
as 'IPSTATS_MIB_INHDRERRORS' is used when ip6_parse_tlv() fails,
which make we use 'SKB_DROP_REASON_IP_INHDR' correspondingly.
However, 'IP_INHDR' is a relatively general reason. Therefore, we
can use other reasons with higher priority in some cases. For example,
'SKB_DROP_REASON_UNHANDLED_PROTO' is used for unknown TLV options.
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Reviewed-by: Jiang Biao <benbjiang@tencent.com>
Reviewed-by: Hao Peng <flyingpeng@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are two call chains for ipv6_hop_jumbo(). The first one is:
ipv6_destopt_rcv() -> ip6_parse_tlv() -> ipv6_hop_jumbo()
On this call chain, the drop statistics will be done in
ipv6_destopt_rcv() with 'IPSTATS_MIB_INHDRERRORS' if ipv6_hop_jumbo()
returns false.
The second call chain is:
ip6_rcv_core() -> ipv6_parse_hopopts() -> ip6_parse_tlv()
And the drop statistics will also be done in ip6_rcv_core() with
'IPSTATS_MIB_INHDRERRORS' if ipv6_hop_jumbo() returns false.
Therefore, the statistics in ipv6_hop_jumbo() is redundant, which
means the drop is counted twice. The statistics in ipv6_hop_jumbo()
is almost the same as the outside, except the
'IPSTATS_MIB_INTRUNCATEDPKTS', which seems that we have to ignore it.
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Reviewed-by: Jiang Biao <benbjiang@tencent.com>
Reviewed-by: Hao Peng <flyingpeng@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Address the following coccicheck warning:
net/ipv6/exthdrs.c:620:44-45: WARNING opportunity for swap()
by using swap() for the swapping of variable values and drop
the tmp (`addr`) variable that is not needed any more.
Signed-off-by: Guo Zhengkui <guozhengkui@vivo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Inline a part of ipv6_fixup_options() to avoid extra overhead on
function call if opt is NULL.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This statement is repeated with the initialization statement
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: luo penghao <luo.penghao@zte.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch anticipates the support for the IOAM insertion inside in-transit
packets, by making a difference between input and output in order to determine
the right value for its hop-limit (inherited from the IPv6 hop-limit).
Input case: happens before ip6_forward, the IPv6 hop-limit is not decremented
yet -> decrement the IOAM hop-limit to reflect the new hop inside the trace.
Output case: happens after ip6_forward, the IPv6 hop-limit has already been
decremented -> keep the same value for the IOAM hop-limit.
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
As presented last month in our "BIG TCP" talk at netdev 0x15,
we plan using IPv6 jumbograms.
One of the minor problem we talked about is the fact that
ip6_parse_tlv() is currently using tables to list known tlvs,
thus using potentially expensive indirect calls.
While we could mitigate this cost using macros from
indirect_call_wrapper.h, we also can get rid of the tables
and let the compiler emit optimized code.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Justin Iurman <justin.iurman@uliege.be>
Cc: Coco Li <lixiaoyan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement support for processing the IOAM Pre-allocated Trace with IPv6,
see [1] and [2]. Introduce a new IPv6 Hop-by-Hop TLV option, see IANA [3].
A new per-interface sysctl is introduced. The value is a boolean to accept (=1)
or ignore (=0, by default) IPv6 IOAM options on ingress for an interface:
- net.ipv6.conf.XXX.ioam6_enabled
Two other sysctls are introduced to define IOAM IDs, represented by an integer.
They are respectively per-namespace and per-interface:
- net.ipv6.ioam6_id
- net.ipv6.conf.XXX.ioam6_id
The value of the first one represents the IOAM ID of the node itself (u32; max
and default value = U32_MAX>>8, due to hop limit concatenation) while the other
represents the IOAM ID of an interface (u16; max and default value = U16_MAX).
Each "ioam6_id" sysctl has a "_wide" equivalent:
- net.ipv6.ioam6_id_wide
- net.ipv6.conf.XXX.ioam6_id_wide
The value of the first one represents the wide IOAM ID of the node itself (u64;
max and default value = U64_MAX>>8, due to hop limit concatenation) while the
other represents the wide IOAM ID of an interface (u32; max and default value
= U32_MAX).
The use of short and wide equivalents is not exclusive, a deployment could
choose to leverage both. For example, net.ipv6.conf.XXX.ioam6_id (short format)
could be an identifier for a physical interface, whereas
net.ipv6.conf.XXX.ioam6_id_wide (wide format) could be an identifier for a
logical sub-interface. Documentation about new sysctls is provided at the end
of this patchset.
Two relativistic hash tables are used: one for IOAM namespaces, the other for
IOAM schemas. A namespace can only have a single active schema and a schema
can only be attached to a single namespace (1:1 relationship).
[1] https://tools.ietf.org/html/draft-ietf-ippm-ioam-ipv6-options
[2] https://tools.ietf.org/html/draft-ietf-ippm-ioam-data
[3] https://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml#ipv6-parameters-2
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
First problem is that optlen is fetched without checking
there is more than one byte to parse.
Fix this by taking care of IPV6_TLV_PAD1 before
fetching optlen (under appropriate sanity checks against len)
Second problem is that IPV6_TLV_PADN checks of zero
padding are performed before the check of remaining length.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Fixes: c1412fce7e ("net/ipv6/exthdrs.c: Strict PadN option checking")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I see no reason why max_dst_opts_cnt and max_hbh_opts_cnt
are fetched from the initial net namespace.
The other sysctls (max_dst_opts_len & max_hbh_opts_len)
are in fact already using the current ns.
Note: it is not clear why ipv6_destopt_rcv() use two ways to
get to the netns :
1) dev_net(dst->dev)
Originally used to increment IPSTATS_MIB_INHDRERRORS
2) dev_net(skb->dev)
Tom used this variant in his patch.
Maybe this calls to use ipv6_skb_net() instead ?
Fixes: 47d3d7ac65 ("ipv6: Implement limits on Hop-by-Hop and Destination options")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@quantonium.net>
Cc: Coco Li <lixiaoyan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As specified in IETF RFC 8754, section 4.3.1.2, if the upper layer
header is IPv4 or IPv6, perform IPv6 decapsulation and resubmit the
decapsulated packet to the IPv4 or IPv6 module.
Only IPv6 decapsulation was implemented. This patch adds support for IPv4
decapsulation.
Link: https://tools.ietf.org/html/rfc8754#section-4.3.1.2
Signed-off-by: Julien Massonneau <julien.massonneau@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit bdb7cc643f ("ipv6: Count interface receive statistics on the
ingress netdev") removed all callees for ipv6_skb_idev(). Hence, since
then, ipv6_skb_idev() is unused and make CC=clang W=1 warns:
net/ipv6/exthdrs.c:909:33:
warning: unused function 'ipv6_skb_idev' [-Wunused-function]
So, remove this unused function and a -Wunused-function warning.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Link: https://lore.kernel.org/r/20201113135012.32499-1-lukas.bulwahn@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Simple fixes which require no deep knowledge of the code.
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes. Also, remove unnecessary
function ipv6_rpl_srh_alloc_size() and replace kzalloc() with kcalloc(),
which has a 2-factor argument form for multiplication.
This code was detected with the help of Coccinelle and, audited and
fixed manually.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds rpl source routing receive handling. Everything works
only if sysconf "rpl_seg_enabled" and source routing is enabled. Mostly
the same behaviour as IPv6 segmentation routing. To handle compression
and uncompression a rpl.c file is created which contains the necessary
functionality. The receive handling will also care about IPv6
encapsulated so far it's specified as possible nexthdr in RFC 6554.
Signed-off-by: Alexander Aring <alex.aring@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>
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>
At present the ipv6_renew_options_kern() function ends up calling into
access_ok() which is problematic if done from inside an interrupt as
access_ok() calls WARN_ON_IN_IRQ() on some (all?) architectures
(x86-64 is affected). Example warning/backtrace is shown below:
WARNING: CPU: 1 PID: 3144 at lib/usercopy.c:11 _copy_from_user+0x85/0x90
...
Call Trace:
<IRQ>
ipv6_renew_option+0xb2/0xf0
ipv6_renew_options+0x26a/0x340
ipv6_renew_options_kern+0x2c/0x40
calipso_req_setattr+0x72/0xe0
netlbl_req_setattr+0x126/0x1b0
selinux_netlbl_inet_conn_request+0x80/0x100
selinux_inet_conn_request+0x6d/0xb0
security_inet_conn_request+0x32/0x50
tcp_conn_request+0x35f/0xe00
? __lock_acquire+0x250/0x16c0
? selinux_socket_sock_rcv_skb+0x1ae/0x210
? tcp_rcv_state_process+0x289/0x106b
tcp_rcv_state_process+0x289/0x106b
? tcp_v6_do_rcv+0x1a7/0x3c0
tcp_v6_do_rcv+0x1a7/0x3c0
tcp_v6_rcv+0xc82/0xcf0
ip6_input_finish+0x10d/0x690
ip6_input+0x45/0x1e0
? ip6_rcv_finish+0x1d0/0x1d0
ipv6_rcv+0x32b/0x880
? ip6_make_skb+0x1e0/0x1e0
__netif_receive_skb_core+0x6f2/0xdf0
? process_backlog+0x85/0x250
? process_backlog+0x85/0x250
? process_backlog+0xec/0x250
process_backlog+0xec/0x250
net_rx_action+0x153/0x480
__do_softirq+0xd9/0x4f7
do_softirq_own_stack+0x2a/0x40
</IRQ>
...
While not present in the backtrace, ipv6_renew_option() ends up calling
access_ok() via the following chain:
access_ok()
_copy_from_user()
copy_from_user()
ipv6_renew_option()
The fix presented in this patch is to perform the userspace copy
earlier in the call chain such that it is only called when the option
data is actually coming from userspace; that place is
do_ipv6_setsockopt(). Not only does this solve the problem seen in
the backtrace above, it also allows us to simplify the code quite a
bit by removing ipv6_renew_options_kern() completely. We also take
this opportunity to cleanup ipv6_renew_options()/ipv6_renew_option()
a small amount as well.
This patch is heavily based on a rough patch by Al Viro. I've taken
his original patch, converted a kmemdup() call in do_ipv6_setsockopt()
to a memdup_user() call, made better use of the e_inval jump target in
the same function, and cleaned up the use ipv6_renew_option() by
ipv6_renew_options().
CC: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The statistics such as InHdrErrors should be counted on the ingress
netdev rather than on the dev from the dst, which is the egress.
Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Function ipv6_push_rthdr4 allows to add an IPv6 Segment Routing Header
to a socket through setsockopt, but the current implementation doesn't
copy possible TLVs at the end of the SRH received from userspace.
Therefore, the execution of the following branch if (sr_has_hmac(sr_phdr))
{ ... } will never complete since the len and type fields of a possible
HMAC TLV are not copied, hence seg6_get_tlv_hmac will return an error,
and the HMAC will not be computed.
This commit adds a memcpy in case TLVs have been appended to the SRH.
Fixes: a149e7c7ce ("ipv6: sr: add support for SRH injection through setsockopt")
Acked-by: David Lebrun <dlebrun@google.com>
Signed-off-by: Mathieu Xhonneux <m.xhonneux@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
RFC 8200 (IPv6) defines Hop-by-Hop options and Destination options
extension headers. Both of these carry a list of TLVs which is
only limited by the maximum length of the extension header (2048
bytes). By the spec a host must process all the TLVs in these
options, however these could be used as a fairly obvious
denial of service attack. I think this could in fact be
a significant DOS vector on the Internet, one mitigating
factor might be that many FWs drop all packets with EH (and
obviously this is only IPv6) so an Internet wide attack might not
be so effective (yet!).
By my calculation, the worse case packet with TLVs in a standard
1500 byte MTU packet that would be processed by the stack contains
1282 invidual TLVs (including pad TLVS) or 724 two byte TLVs. I
wrote a quick test program that floods a whole bunch of these
packets to a host and sure enough there is substantial time spent
in ip6_parse_tlv. These packets contain nothing but unknown TLVS
(that are ignored), TLV padding, and bogus UDP header with zero
payload length.
25.38% [kernel] [k] __fib6_clean_all
21.63% [kernel] [k] ip6_parse_tlv
4.21% [kernel] [k] __local_bh_enable_ip
2.18% [kernel] [k] ip6_pol_route.isra.39
1.98% [kernel] [k] fib6_walk_continue
1.88% [kernel] [k] _raw_write_lock_bh
1.65% [kernel] [k] dst_release
This patch adds configurable limits to Destination and Hop-by-Hop
options. There are three limits that may be set:
- Limit the number of options in a Hop-by-Hop or Destination options
extension header.
- Limit the byte length of a Hop-by-Hop or Destination options
extension header.
- Disallow unrecognized options in a Hop-by-Hop or Destination
options extension header.
The limits are set in corresponding sysctls:
ipv6.sysctl.max_dst_opts_cnt
ipv6.sysctl.max_hbh_opts_cnt
ipv6.sysctl.max_dst_opts_len
ipv6.sysctl.max_hbh_opts_len
If a max_*_opts_cnt is less than zero then unknown TLVs are disallowed.
The number of known TLVs that are allowed is the absolute value of
this number.
If a limit is exceeded when processing an extension header the packet is
dropped.
Default values are set to 8 for options counts, and set to INT_MAX
for maximum length. Note the choice to limit options to 8 is an
arbitrary guess (roughly based on the fact that the stack supports
three HBH options and just one destination option).
These limits have being proposed in draft-ietf-6man-rfc6434-bis.
Tested (by Martin Lau)
I tested out 1 thread (i.e. one raw_udp process).
I changed the net.ipv6.max_dst_(opts|hbh)_number between 8 to 2048.
With sysctls setting to 2048, the softirq% is packed to 100%.
With 8, the softirq% is almost unnoticable from mpstat.
v2;
- Code and documention cleanup.
- Change references of RFC2460 to be RFC8200.
- Add reference to RFC6434-bis where the limits will be in standard.
Signed-off-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
make use of the swap macro and remove unnecessary variable tmp_addr.
This makes the code easier to read and maintain.
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Notice that in some cases I placed the "fall through" comment
on its own line, which is what GCC is expecting to find.
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The seg6_validate_srh() function only allows SRHs whose active segment is
the first segment of the path. However, an application may insert an SRH
whose active segment is not the first one. Such an application might be
for example an SR-aware Virtual Network Function.
This patch enables to insert SRHs with an arbitrary active segment.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 67a51780ae ("ipv6: udp: leverage scratch area
helpers") udp6_recvmsg() read the skb len from the scratch area,
to avoid a cache miss.
But the UDP6 rx path support RFC 2675 UDPv6 jumbograms, and their
length exceeds the 16 bits available in the scratch area. As a side
effect the length returned by recvmsg() is:
<ingress datagram len> % (1<<16)
This commit addresses the issue allocating one more bit in the
IP6CB flags field and setting it for incoming jumbograms.
Such field is still in the first cacheline, so at recvmsg()
time we can check it and fallback to access skb->len if
required, without a measurable overhead.
Fixes: 67a51780ae ("ipv6: udp: leverage scratch area helpers")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.
Make these functions return void * and remove all the casts across
the tree, adding a (u8 *) cast only where the unsigned char pointer
was used directly, all done with the following spatch:
@@
expression SKB, LEN;
typedef u8;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
@@
- *(fn(SKB, LEN))
+ *(u8 *)fn(SKB, LEN)
@@
expression E, SKB, LEN;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
type T;
@@
- E = ((T *)(fn(SKB, LEN)))
+ E = fn(SKB, LEN)
@@
expression SKB, LEN;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
@@
- fn(SKB, LEN)[0]
+ *(u8 *)fn(SKB, LEN)
Note that the last part there converts from push(...)[0] to the
more idiomatic *(u8 *)push(...).
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since that change also made the nfrag function not necessary
for exports, remove it.
Fixes: 89a23c8b52 ("ip6_tunnel: Fix missing tunnel encapsulation limit option")
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit a149e7c7ce ("ipv6: sr: add support for SRH injection through
setsockopt") introduced handling of IPV6_SRCRT_TYPE_4, but at the same
time restricted it to only IPV6_SRCRT_TYPE_0 and
IPV6_SRCRT_TYPE_4. Previously, ipv6_push_exthdr() and fl6_update_dst()
would also handle other values (ie STRICT and TYPE_2).
Restore previous source routing behavior, by handling IPV6_SRCRT_STRICT
and IPV6_SRCRT_TYPE_2 the same way as IPV6_SRCRT_TYPE_0 in
ipv6_push_exthdr() and fl6_update_dst().
Fixes: a149e7c7ce ("ipv6: sr: add support for SRH injection through setsockopt")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The icmpv6_param_prob() function already does a kfree_skb(),
this patch removes the duplicate one.
Fixes: 1ababeba4a ("ipv6: implement dataplane support for rthdr type 4 (Segment Routing Header)")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the latest version of the IPv6 Segment Routing IETF draft [1] the
cleanup flag is removed and the flags field length is shrunk from 16 bits
to 8 bits. As a consequence, the input of the HMAC computation is modified
in a non-backward compatible way by covering the whole octet of flags
instead of only the cleanup bit. As such, if an implementation compatible
with the latest draft computes the HMAC of an SRH who has other flags set
to 1, then the HMAC result would differ from the current implementation.
This patch carries those modifications to prevent conflict with other
implementations of IPv6 SR.
[1] https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-05
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
ktime is a union because the initial implementation stored the time in
scalar nanoseconds on 64 bit machine and in a endianess optimized timespec
variant for 32bit machines. The Y2038 cleanup removed the timespec variant
and switched everything to scalar nanoseconds. The union remained, but
become completely pointless.
Get rid of the union and just keep ktime_t as simple typedef of type s64.
The conversion was done with coccinelle and some manual mopping up.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
This patch adds support for per-socket SRH injection with the setsockopt
system call through the IPPROTO_IPV6, IPV6_RTHDR options.
The SRH is pushed through the ipv6_push_nfrag_opts function.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch prepares for insertion of SRH through setsockopt().
The new source address argument is used when an HMAC field is
present in the SRH, which must be filled. The HMAC signature
process requires the source address as input text.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
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>
Justin Iurman