Commit Graph

132 Commits

Author SHA1 Message Date
Ziyang Xuan
85f0173df3 ipv6/addrconf: fix a null-ptr-deref bug for ip6_ptr
Change net device's MTU to smaller than IPV6_MIN_MTU or unregister
device while matching route. That may trigger null-ptr-deref bug
for ip6_ptr probability as following.

=========================================================
BUG: KASAN: null-ptr-deref in find_match.part.0+0x70/0x134
Read of size 4 at addr 0000000000000308 by task ping6/263

CPU: 2 PID: 263 Comm: ping6 Not tainted 5.19.0-rc7+ #14
Call trace:
 dump_backtrace+0x1a8/0x230
 show_stack+0x20/0x70
 dump_stack_lvl+0x68/0x84
 print_report+0xc4/0x120
 kasan_report+0x84/0x120
 __asan_load4+0x94/0xd0
 find_match.part.0+0x70/0x134
 __find_rr_leaf+0x408/0x470
 fib6_table_lookup+0x264/0x540
 ip6_pol_route+0xf4/0x260
 ip6_pol_route_output+0x58/0x70
 fib6_rule_lookup+0x1a8/0x330
 ip6_route_output_flags_noref+0xd8/0x1a0
 ip6_route_output_flags+0x58/0x160
 ip6_dst_lookup_tail+0x5b4/0x85c
 ip6_dst_lookup_flow+0x98/0x120
 rawv6_sendmsg+0x49c/0xc70
 inet_sendmsg+0x68/0x94

Reproducer as following:
Firstly, prepare conditions:
$ip netns add ns1
$ip netns add ns2
$ip link add veth1 type veth peer name veth2
$ip link set veth1 netns ns1
$ip link set veth2 netns ns2
$ip netns exec ns1 ip -6 addr add 2001:0db8:0:f101::1/64 dev veth1
$ip netns exec ns2 ip -6 addr add 2001:0db8:0:f101::2/64 dev veth2
$ip netns exec ns1 ifconfig veth1 up
$ip netns exec ns2 ifconfig veth2 up
$ip netns exec ns1 ip -6 route add 2000::/64 dev veth1 metric 1
$ip netns exec ns2 ip -6 route add 2001::/64 dev veth2 metric 1

Secondly, execute the following two commands in two ssh windows
respectively:
$ip netns exec ns1 sh
$while true; do ip -6 addr add 2001:0db8:0:f101::1/64 dev veth1; ip -6 route add 2000::/64 dev veth1 metric 1; ping6 2000::2; done

$ip netns exec ns1 sh
$while true; do ip link set veth1 mtu 1000; ip link set veth1 mtu 1500; sleep 5; done

It is because ip6_ptr has been assigned to NULL in addrconf_ifdown() firstly,
then ip6_ignore_linkdown() accesses ip6_ptr directly without NULL check.

	cpu0			cpu1
fib6_table_lookup
__find_rr_leaf
			addrconf_notify [ NETDEV_CHANGEMTU ]
			addrconf_ifdown
			RCU_INIT_POINTER(dev->ip6_ptr, NULL)
find_match
ip6_ignore_linkdown

So we can add NULL check for ip6_ptr before using in ip6_ignore_linkdown() to
fix the null-ptr-deref bug.

Fixes: dcd1f57295 ("net/ipv6: Remove fib6_idev")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220728013307.656257-1-william.xuanziyang@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-28 10:42:44 -07:00
Jacques de Laval
47f0bd5032 net: Add new protocol attribute to IP addresses
This patch adds a new protocol attribute to IPv4 and IPv6 addresses.
Inspiration was taken from the protocol attribute of routes. User space
applications like iproute2 can set/get the protocol with the Netlink API.

The attribute is stored as an 8-bit unsigned integer.

The protocol attribute is set by kernel for these categories:

- IPv4 and IPv6 loopback addresses
- IPv6 addresses generated from router announcements
- IPv6 link local addresses

User space may pass custom protocols, not defined by the kernel.

Grouping addresses on their origin is useful in scenarios where you want
to distinguish between addresses based on who added them, e.g. kernel
vs. user space.

Tagging addresses with a string label is an existing feature that could be
used as a solution. Unfortunately the max length of a label is
15 characters, and for compatibility reasons the label must be prefixed
with the name of the device followed by a colon. Since device names also
have a max length of 15 characters, only -1 characters is guaranteed to be
available for any origin tag, which is not that much.

A reference implementation of user space setting and getting protocols
is available for iproute2:

9a6ea18bd7

Signed-off-by: Jacques de Laval <Jacques.De.Laval@westermo.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220217150202.80802-1-Jacques.De.Laval@westermo.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-18 21:20:06 -08:00
Ignat Korchagin
26394fc118 ipv6: mcast: use rcu-safe version of ipv6_get_lladdr()
Some time ago 8965779d2c ("ipv6,mcast: always hold idev->lock before mca_lock")
switched ipv6_get_lladdr() to __ipv6_get_lladdr(), which is rcu-unsafe
version. That was OK, because idev->lock was held for these codepaths.

In 88e2ca3080 ("mld: convert ifmcaddr6 to RCU") these external locks were
removed, so we probably need to restore the original rcu-safe call.

Otherwise, we occasionally get a machine crashed/stalled with the following
in dmesg:

[ 3405.966610][T230589] general protection fault, probably for non-canonical address 0xdead00000000008c: 0000 [#1] SMP NOPTI
[ 3405.982083][T230589] CPU: 44 PID: 230589 Comm: kworker/44:3 Tainted: G           O      5.15.19-cloudflare-2022.2.1 #1
[ 3405.998061][T230589] Hardware name: SUPA-COOL-SERV
[ 3406.009552][T230589] Workqueue: mld mld_ifc_work
[ 3406.017224][T230589] RIP: 0010:__ipv6_get_lladdr+0x34/0x60
[ 3406.025780][T230589] Code: 57 10 48 83 c7 08 48 89 e5 48 39 d7 74 3e 48 8d 82 38 ff ff ff eb 13 48 8b 90 d0 00 00 00 48 8d 82 38 ff ff ff 48 39 d7 74 22 <66> 83 78 32 20 77 1b 75 e4 89 ca 23 50 2c 75 dd 48 8b 50 08 48 8b
[ 3406.055748][T230589] RSP: 0018:ffff94e4b3fc3d10 EFLAGS: 00010202
[ 3406.065617][T230589] RAX: dead00000000005a RBX: ffff94e4b3fc3d30 RCX: 0000000000000040
[ 3406.077477][T230589] RDX: dead000000000122 RSI: ffff94e4b3fc3d30 RDI: ffff8c3a31431008
[ 3406.089389][T230589] RBP: ffff94e4b3fc3d10 R08: 0000000000000000 R09: 0000000000000000
[ 3406.101445][T230589] R10: ffff8c3a31430000 R11: 000000000000000b R12: ffff8c2c37887100
[ 3406.113553][T230589] R13: ffff8c3a39537000 R14: 00000000000005dc R15: ffff8c3a31431000
[ 3406.125730][T230589] FS:  0000000000000000(0000) GS:ffff8c3b9fc80000(0000) knlGS:0000000000000000
[ 3406.138992][T230589] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3406.149895][T230589] CR2: 00007f0dfea1db60 CR3: 000000387b5f2000 CR4: 0000000000350ee0
[ 3406.162421][T230589] Call Trace:
[ 3406.170235][T230589]  <TASK>
[ 3406.177736][T230589]  mld_newpack+0xfe/0x1a0
[ 3406.186686][T230589]  add_grhead+0x87/0xa0
[ 3406.195498][T230589]  add_grec+0x485/0x4e0
[ 3406.204310][T230589]  ? newidle_balance+0x126/0x3f0
[ 3406.214024][T230589]  mld_ifc_work+0x15d/0x450
[ 3406.223279][T230589]  process_one_work+0x1e6/0x380
[ 3406.232982][T230589]  worker_thread+0x50/0x3a0
[ 3406.242371][T230589]  ? rescuer_thread+0x360/0x360
[ 3406.252175][T230589]  kthread+0x127/0x150
[ 3406.261197][T230589]  ? set_kthread_struct+0x40/0x40
[ 3406.271287][T230589]  ret_from_fork+0x22/0x30
[ 3406.280812][T230589]  </TASK>
[ 3406.288937][T230589] Modules linked in: ... [last unloaded: kheaders]
[ 3406.476714][T230589] ---[ end trace 3525a7655f2f3b9e ]---

Fixes: 88e2ca3080 ("mld: convert ifmcaddr6 to RCU")
Reported-by: David Pinilla Caparros <dpini@cloudflare.com>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-14 13:30:37 +00:00
Guillaume Nault
36268983e9 Revert "ipv6: Honor all IPv6 PIO Valid Lifetime values"
This reverts commit b75326c201.

This commit breaks Linux compatibility with USGv6 tests. The RFC this
commit was based on is actually an expired draft: no published RFC
currently allows the new behaviour it introduced.

Without full IETF endorsement, the flash renumbering scenario this
patch was supposed to enable is never going to work, as other IPv6
equipements on the same LAN will keep the 2 hours limit.

Fixes: b75326c201 ("ipv6: Honor all IPv6 PIO Valid Lifetime values")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-27 13:35:14 +00:00
Linus Lüssing
9901408815 net: bridge: mcast: fix broken length + header check for MRDv6 Adv.
The IPv6 Multicast Router Advertisements parsing has the following two
issues:

For one thing, ICMPv6 MRD Advertisements are smaller than ICMPv6 MLD
messages (ICMPv6 MRD Adv.: 8 bytes vs. ICMPv6 MLDv1/2: >= 24 bytes,
assuming MLDv2 Reports with at least one multicast address entry).
When ipv6_mc_check_mld_msg() tries to parse an Multicast Router
Advertisement its MLD length check will fail - and it will wrongly
return -EINVAL, even if we have a valid MRD Advertisement. With the
returned -EINVAL the bridge code will assume a broken packet and will
wrongly discard it, potentially leading to multicast packet loss towards
multicast routers.

The second issue is the MRD header parsing in
br_ip6_multicast_mrd_rcv(): It wrongly checks for an ICMPv6 header
immediately after the IPv6 header (IPv6 next header type). However
according to RFC4286, section 2 all MRD messages contain a Router Alert
option (just like MLD). So instead there is an IPv6 Hop-by-Hop option
for the Router Alert between the IPv6 and ICMPv6 header, again leading
to the bridge wrongly discarding Multicast Router Advertisements.

To fix these two issues, introduce a new return value -ENODATA to
ipv6_mc_check_mld() to indicate a valid ICMPv6 packet with a hop-by-hop
option which is not an MLD but potentially an MRD packet. This also
simplifies further parsing in the bridge code, as ipv6_mc_check_mld()
already fully checks the ICMPv6 header and hop-by-hop option.

These issues were found and fixed with the help of the mrdisc tool
(https://github.com/troglobit/mrdisc).

Fixes: 4b3087c7e3 ("bridge: Snoop Multicast Router Advertisements")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-27 14:02:06 -07:00
Xin Long
4ef1a7cb08 ipv6: some fixes for ipv6_dev_find()
This patch is to do 3 things for ipv6_dev_find():

  As David A. noticed,

  - rt6_lookup() is not really needed. Different from __ip_dev_find(),
    ipv6_dev_find() doesn't have a compatibility problem, so remove it.

  As Hideaki suggested,

  - "valid" (non-tentative) check for the address is also needed.
    ipv6_chk_addr() calls ipv6_chk_addr_and_flags(), which will
    traverse the address hash list, but it's heavy to be called
    inside ipv6_dev_find(). This patch is to reuse the code of
    ipv6_chk_addr_and_flags() for ipv6_dev_find().

  - dev parameter is passed into ipv6_dev_find(), as link-local
    addresses from user space has sin6_scope_id set and the dev
    lookup needs it.

Fixes: 81f6cb3122 ("ipv6: add ipv6_dev_find()")
Suggested-by: YOSHIFUJI Hideaki <hideaki.yoshifuji@miraclelinux.com>
Reported-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-18 15:58:53 -07:00
Xin Long
81f6cb3122 ipv6: add ipv6_dev_find()
This is to add an ip_dev_find like function for ipv6, used to find
the dev by saddr.

It will be used by TIPC protocol. So also export it.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-05 12:19:52 -07:00
Cong Wang
8c0de6e96c ipv6: fix memory leaks on IPV6_ADDRFORM path
IPV6_ADDRFORM causes resource leaks when converting an IPv6 socket
to IPv4, particularly struct ipv6_ac_socklist. Similar to
struct ipv6_mc_socklist, we should just close it on this path.

This bug can be easily reproduced with the following C program:

  #include <stdio.h>
  #include <string.h>
  #include <sys/types.h>
  #include <sys/socket.h>
  #include <arpa/inet.h>

  int main()
  {
    int s, value;
    struct sockaddr_in6 addr;
    struct ipv6_mreq m6;

    s = socket(AF_INET6, SOCK_DGRAM, 0);
    addr.sin6_family = AF_INET6;
    addr.sin6_port = htons(5000);
    inet_pton(AF_INET6, "::ffff:192.168.122.194", &addr.sin6_addr);
    connect(s, (struct sockaddr *)&addr, sizeof(addr));

    inet_pton(AF_INET6, "fe80::AAAA", &m6.ipv6mr_multiaddr);
    m6.ipv6mr_interface = 5;
    setsockopt(s, SOL_IPV6, IPV6_JOIN_ANYCAST, &m6, sizeof(m6));

    value = AF_INET;
    setsockopt(s, SOL_IPV6, IPV6_ADDRFORM, &value, sizeof(value));

    close(s);
    return 0;
  }

Reported-by: ch3332xr@gmail.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-30 16:30:55 -07:00
Fernando Gont
b75326c201 ipv6: Honor all IPv6 PIO Valid Lifetime values
RFC4862 5.5.3 e) prevents received Router Advertisements from reducing
the Valid Lifetime of configured addresses to less than two hours, thus
preventing hosts from reacting to the information provided by a router
that has positive knowledge that a prefix has become invalid.

This patch makes hosts honor all Valid Lifetime values, as per
draft-gont-6man-slaac-renum-06, Section 4.2. This is meant to help
mitigate the problem discussed in draft-ietf-v6ops-slaac-renum.

Note: Attacks aiming at disabling an advertised prefix via a Valid
Lifetime of 0 are not really more harmful than other attacks
that can be performed via forged RA messages, such as those
aiming at completely disabling a next-hop router via an RA that
advertises a Router Lifetime of 0, or performing a Denial of
Service (DoS) attack by advertising illegitimate prefixes via
forged PIOs.  In scenarios where RA-based attacks are of concern,
proper mitigations such as RA-Guard [RFC6105] [RFC7113] should
be implemented.

Signed-off-by: Fernando Gont <fgont@si6networks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-23 12:29:21 -07:00
Alexander Aring
f37c605936 addrconf: add functionality to check on rpl requirements
This patch adds a functionality to addrconf to check on a specific RPL
address configuration. According to RFC 6554:

To detect loops in the SRH, a router MUST determine if the SRH
includes multiple addresses assigned to any interface on that
router. If such addresses appear more than once and are separated by
at least one address not assigned to that router.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-29 22:30:57 -07:00
Sven Eckelmann
54e1f08bdd ipv6: Annotate ipv6_addr_is_* bitwise pointer casts
The sparse commit 6002ded74587 ("add a flag to warn on casts to/from
bitwise pointers") introduced a check for non-direct casts from/to
restricted datatypes (when -Wbitwise-pointer is enabled).

This triggered a warning in the 64 bit optimized ipv6_addr_is_*() functions
because sparse doesn't know that the buffer already points to some data in
the correct bitwise integer format. But these were correct and can
therefore be marked with __force to signalize sparse an intended cast to a
specific bitwise type.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-16 16:09:44 -08:00
David S. Miller
3289086210 ipv6: Make ipv6_mc_may_pull() return bool.
Consistent with how pskb_may_pull() also now does so.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-07 09:37:27 -04:00
Stefano Brivio
3a7ef457e8 ipv6: Fix return value of ipv6_mc_may_pull() for malformed packets
Commit ba5ea61462 ("bridge: simplify ip_mc_check_igmp() and
ipv6_mc_check_mld() calls") replaces direct calls to pskb_may_pull()
in br_ipv6_multicast_mld2_report() with calls to ipv6_mc_may_pull(),
that returns -EINVAL on buffers too short to be valid IPv6 packets,
while maintaining the previous handling of the return code.

This leads to the direct opposite of the intended effect: if the
packet is malformed, -EINVAL evaluates as true, and we'll happily
proceed with the processing.

Return 0 if the packet is too short, in the same way as this was
fixed for IPv4 by commit 083b78a9ed ("ip: fix ip_mc_may_pull()
return value").

I don't have a reproducer for this, unlike the one referred to by
the IPv4 commit, but this is clearly broken.

Fixes: ba5ea61462 ("bridge: simplify ip_mc_check_igmp() and ipv6_mc_check_mld() calls")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-19 17:19:46 -07:00
Stephen Suryaputra
e1ae5c2ea4 vrf: Increment Icmp6InMsgs on the original netdev
Get the ingress interface and increment ICMP counters based on that
instead of skb->dev when the the dev is a VRF device.

This is a follow up on the following message:
https://www.spinics.net/lists/netdev/msg560268.html

v2: Avoid changing skb->dev since it has unintended effect for local
    delivery (David Ahern).
Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-12 11:00:11 -07:00
David Ahern
3616d08bcb ipv6: Move ipv6 stubs to a separate header file
The number of stubs is growing and has nothing to do with addrconf.
Move the definition of the stubs to a separate header file and update
users. In the move, drop the vxlan specific comment before ipv6_stub.

Code move only; no functional change intended.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-29 10:53:45 -07:00
David Ahern
6d3d07b45c ipv6: Refactor fib6_ignore_linkdown
fib6_ignore_linkdown takes a fib6_info but only looks at the net_device
and its IPv6 config. Change it to take a net_device over a fib6_info as
its input argument.

In addition, move it to a header file to make the check inline and usable
later with IPv4 code without going through the ipv6 stub, and rename to
ip6_ignore_linkdown since it is only checking the setting based on the
ipv6 struct on a device.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-29 10:48:04 -07:00
Peter Oskolkov
9b0a6a9dba ipv6_stub: add ipv6_route_input stub/proxy.
Proxy ip6_route_input via ipv6_stub, for later use by lwt bpf ip encap
(see the next patch in the patchset).

Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-13 18:27:55 -08:00
Linus Lüssing
4b3087c7e3 bridge: Snoop Multicast Router Advertisements
When multiple multicast routers are present in a broadcast domain then
only one of them will be detectable via IGMP/MLD query snooping. The
multicast router with the lowest IP address will become the selected and
active querier while all other multicast routers will then refrain from
sending queries.

To detect such rather silent multicast routers, too, RFC4286
("Multicast Router Discovery") provides a standardized protocol to
detect multicast routers for multicast snooping switches.

This patch implements the necessary MRD Advertisement message parsing
and after successful processing adds such routers to the internal
multicast router list.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-22 17:18:09 -08:00
Linus Lüssing
ba5ea61462 bridge: simplify ip_mc_check_igmp() and ipv6_mc_check_mld() calls
This patch refactors ip_mc_check_igmp(), ipv6_mc_check_mld() and
their callers (more precisely, the Linux bridge) to not rely on
the skb_trimmed parameter anymore.

An skb with its tail trimmed to the IP packet length was initially
introduced for the following three reasons:

1) To be able to verify the ICMPv6 checksum.
2) To be able to distinguish the version of an IGMP or MLD query.
   They are distinguishable only by their size.
3) To avoid parsing data for an IGMPv3 or MLDv2 report that is
   beyond the IP packet but still within the skb.

The first case still uses a cloned and potentially trimmed skb to
verfiy. However, there is no need to propagate it to the caller.
For the second and third case explicit IP packet length checks were
added.

This hopefully makes ip_mc_check_igmp() and ipv6_mc_check_mld() easier
to read and verfiy, as well as easier to use.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-22 17:18:08 -08:00
Jeff Barnhill
2384d02520 net/ipv6: Add anycast addresses to a global hashtable
icmp6_send() function is expensive on systems with a large number of
interfaces. Every time it’s called, it has to verify that the source
address does not correspond to an existing anycast address by looping
through every device and every anycast address on the device.  This can
result in significant delays for a CPU when there are a large number of
neighbors and ND timers are frequently timing out and calling
neigh_invalidate().

Add anycast addresses to a global hashtable to allow quick searching for
matching anycast addresses.  This is based on inet6_addr_lst in addrconf.c.

Signed-off-by: Jeff Barnhill <0xeffeff@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-02 23:54:56 -07:00
Joe Stringer
8a615c6b03 bpf: Allow sk_lookup with IPv6 module
This is a more complete fix than d71019b54b ("net: core: Fix build
with CONFIG_IPV6=m"), so that IPv6 sockets may be looked up if the IPv6
module is loaded (not just if it's compiled in).

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-15 16:08:39 -07:00
Martin KaFai Lau
2dbb9b9e6d bpf: Introduce BPF_PROG_TYPE_SK_REUSEPORT
This patch adds a BPF_PROG_TYPE_SK_REUSEPORT which can select
a SO_REUSEPORT sk from a BPF_MAP_TYPE_REUSEPORT_ARRAY.  Like other
non SK_FILTER/CGROUP_SKB program, it requires CAP_SYS_ADMIN.

BPF_PROG_TYPE_SK_REUSEPORT introduces "struct sk_reuseport_kern"
to store the bpf context instead of using the skb->cb[48].

At the SO_REUSEPORT sk lookup time, it is in the middle of transiting
from a lower layer (ipv4/ipv6) to a upper layer (udp/tcp).  At this
point,  it is not always clear where the bpf context can be appended
in the skb->cb[48] to avoid saving-and-restoring cb[].  Even putting
aside the difference between ipv4-vs-ipv6 and udp-vs-tcp.  It is not
clear if the lower layer is only ipv4 and ipv6 in the future and
will it not touch the cb[] again before transiting to the upper
layer.

For example, in udp_gro_receive(), it uses the 48 byte NAPI_GRO_CB
instead of IP[6]CB and it may still modify the cb[] after calling
the udp[46]_lib_lookup_skb().  Because of the above reason, if
sk->cb is used for the bpf ctx, saving-and-restoring is needed
and likely the whole 48 bytes cb[] has to be saved and restored.

Instead of saving, setting and restoring the cb[], this patch opts
to create a new "struct sk_reuseport_kern" and setting the needed
values in there.

The new BPF_PROG_TYPE_SK_REUSEPORT and "struct sk_reuseport_(kern|md)"
will serve all ipv4/ipv6 + udp/tcp combinations.  There is no protocol
specific usage at this point and it is also inline with the current
sock_reuseport.c implementation (i.e. no protocol specific requirement).

In "struct sk_reuseport_md", this patch exposes data/data_end/len
with semantic similar to other existing usages.  Together
with "bpf_skb_load_bytes()" and "bpf_skb_load_bytes_relative()",
the bpf prog can peek anywhere in the skb.  The "bind_inany" tells
the bpf prog that the reuseport group is bind-ed to a local
INANY address which cannot be learned from skb.

The new "bind_inany" is added to "struct sock_reuseport" which will be
used when running the new "BPF_PROG_TYPE_SK_REUSEPORT" bpf prog in order
to avoid repeating the "bind INANY" test on
"sk_v6_rcv_saddr/sk->sk_rcv_saddr" every time a bpf prog is run.  It can
only be properly initialized when a "sk->sk_reuseport" enabled sk is
adding to a hashtable (i.e. during "reuseport_alloc()" and
"reuseport_add_sock()").

The new "sk_select_reuseport()" is the main helper that the
bpf prog will use to select a SO_REUSEPORT sk.  It is the only function
that can use the new BPF_MAP_TYPE_REUSEPORT_ARRAY.  As mentioned in
the earlier patch, the validity of a selected sk is checked in
run time in "sk_select_reuseport()".  Doing the check in
verification time is difficult and inflexible (consider the map-in-map
use case).  The runtime check is to compare the selected sk's reuseport_id
with the reuseport_id that we want.  This helper will return -EXXX if the
selected sk cannot serve the incoming request (e.g. reuseport_id
not match).  The bpf prog can decide if it wants to do SK_DROP as its
discretion.

When the bpf prog returns SK_PASS, the kernel will check if a
valid sk has been selected (i.e. "reuse_kern->selected_sk != NULL").
If it does , it will use the selected sk.  If not, the kernel
will select one from "reuse->socks[]" (as before this patch).

The SK_DROP and SK_PASS handling logic will be in the next patch.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-11 01:58:46 +02:00
David Ahern
8308f3ff17 net/ipv6: Add support for specifying metric of connected routes
Add support for IFA_RT_PRIORITY to ipv6 addresses.

If the metric is changed on an existing address then the new route
is inserted before removing the old one. Since the metric is one
of the route keys, the prefix route can not be atomically replaced.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-29 10:12:45 -04:00
David Ahern
e6464b8c63 net/ipv6: Convert ipv6_add_addr to struct ifa6_config
Move config parameters for adding an ipv6 address to a struct. struct
names stem from inet6_rtm_newaddr which is the modern handler for
adding an address.

Start the conversion to ifa6_config with ipv6_add_addr. This is an argument
move only; no functional change intended. Mapping of variable changes:

    addr      -->  cfg->pfx
    peer_addr -->  cfg->peer_pfx
    pfxlen    -->  cfg->plen
    flags     -->  cfg->ifa_flags

scope, valid_lft, prefered_lft have the same names within cfg
(with corrected spelling).

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-29 10:12:44 -04:00
David Ahern
901731b882 net/ipv6: Add helper to return path MTU based on fib result
Determine path MTU from a FIB lookup result. Logic is based on
ip6_dst_mtu_forward plus lookup of nexthop exception.

Add ip6_dst_mtu_forward to ipv6_stubs to handle access by core
bpf code.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-22 10:51:09 +02:00
David Ahern
65a2022e89 net/ipv6: Add fib lookup stubs for use in bpf helper
Add stubs to retrieve a handle to an IPv6 FIB table, fib6_get_table,
a stub to do a lookup in a specific table, fib6_table_lookup, and
a stub for a full route lookup.

The stubs are needed for core bpf code to handle the case when the
IPv6 module is not builtin.

Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-11 00:10:57 +02:00
Stephen Suryaputra
bdb7cc643f ipv6: Count interface receive statistics on the ingress netdev
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>
2018-04-17 13:39:51 -04:00
Andrey Ignatov
d74bad4e74 bpf: Hooks for sys_connect
== 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>
2018-03-31 02:15:54 +02:00
David Ahern
232378e8db net/ipv6: Change address check to always take a device argument
ipv6_chk_addr_and_flags determines if an address is a local address and
optionally if it is an address on a specific device. For example, it is
called by ip6_route_info_create to determine if a given gateway address
is a local address. The address check currently does not consider L3
domains and as a result does not allow a route to be added in one VRF
if the nexthop points to an address in a second VRF. e.g.,

    $ ip route add 2001:db8:1::/64 vrf r2 via 2001:db8:102::23
    Error: Invalid gateway address.

where 2001:db8:102::23 is an address on an interface in vrf r1.

ipv6_chk_addr_and_flags needs to allow callers to always pass in a device
with a separate argument to not limit the address to the specific device.
The device is used used to determine the L3 domain of interest.

To that end add an argument to skip the device check and update callers
to always pass a device where possible and use the new argument to mean
any address in the domain.

Update a handful of users of ipv6_chk_addr with a NULL dev argument. This
patch handles the change to these callers without adding the domain check.

ip6_validate_gw needs to handle 2 cases - one where the device is given
as part of the nexthop spec and the other where the device is resolved.
There is at least 1 VRF case where deferring the check to only after
the route lookup has resolved the device fails with an unintuitive error
"RTNETLINK answers: No route to host" as opposed to the preferred
"Error: Gateway can not be a local address." The 'no route to host'
error is because of the fallback to a full lookup. The check is done
twice to avoid this error.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-16 11:28:38 -04:00
Florian Westphal
a3fde2addd rtnetlink: ipv6: convert remaining users to rtnl_register_module
convert remaining users of rtnl_register to rtnl_register_module
and un-export rtnl_register.

Requested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-04 13:35:36 -05:00
Eric Dumazet
27c565ae9d ipv6: remove IN6_ADDR_HSIZE from addrconf.h
IN6_ADDR_HSIZE is private to addrconf.c, move it here to avoid
confusion.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-05 09:17:27 +09:00
David S. Miller
2a171788ba Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Files removed in 'net-next' had their license header updated
in 'net'.  We take the remove from 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-04 09:26:51 +09:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Vishwanath Pai
da13c59b99 net: display hw address of source machine during ipv6 DAD failure
This patch updates the error messages displayed in kernel log to include
hwaddress of the source machine that caused ipv6 duplicate address
detection failures.

Examples:

a) When we receive a NA packet from another machine advertising our
address:

ICMPv6: NA: 34🆎cd:56:11:e8 advertised our address 2001:db8:: on eth0!

b) When we detect DAD failure during address assignment to an interface:

IPv6: eth0: IPv6 duplicate address 2001:db8:: used by 34🆎cd:56:11:e8
detected!

v2:
    Changed %pI6 to %pI6c in ndisc_recv_na()
    Chaged the v6 address in the commit message to 2001:db8::

Suggested-by: Igor Lubashev <ilubashe@akamai.com>
Signed-off-by: Vishwanath Pai <vpai@akamai.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-01 20:53:49 +09:00
Eric Dumazet
3f27fb2321 ipv6: addrconf: add per netns perturbation in inet6_addr_hash()
Bring IPv6 in par with IPv4 :

- Use net_hash_mix() to spread addresses a bit more.
- Use 256 slots hash table instead of 16

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-24 17:54:19 +09:00
David Ahern
de95e04791 net: Add extack to validator_info structs used for address notifier
Add extack to in_validator_info and in6_validator_info. Update the one
user of each, ipvlan, to return an error message for failures.

Only manual configuration of an address is plumbed in the IPv6 code path.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-20 13:15:07 +01:00
Joe Perches
7016e06271 net: Convert int functions to bool
Global function ipv6_rcv_saddr_equal and static functions
ipv6_rcv_saddr_equal and ipv4_rcv_saddr_equal currently return int.

bool is slightly more descriptive for these functions so change
their return type from int to bool.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-18 11:40:03 -07:00
Eric Dumazet
12d94a8049 ipv6: fix NULL dereference in ip6_route_dev_notify()
Based on a syzkaller report [1], I found that a per cpu allocation
failure in snmp6_alloc_dev() would then lead to NULL dereference in
ip6_route_dev_notify().

It seems this is a very old bug, thus no Fixes tag in this submission.

Let's add in6_dev_put_clear() helper, as we will probably use
it elsewhere (once available/present in net-next)

[1]
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 17294 Comm: syz-executor6 Not tainted 4.13.0-rc2+ #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88019f456680 task.stack: ffff8801c6e58000
RIP: 0010:__read_once_size include/linux/compiler.h:250 [inline]
RIP: 0010:atomic_read arch/x86/include/asm/atomic.h:26 [inline]
RIP: 0010:refcount_sub_and_test+0x7d/0x1b0 lib/refcount.c:178
RSP: 0018:ffff8801c6e5f1b0 EFLAGS: 00010202
RAX: 0000000000000037 RBX: dffffc0000000000 RCX: ffffc90005d25000
RDX: ffff8801c6e5f218 RSI: ffffffff82342bbf RDI: 0000000000000001
RBP: ffff8801c6e5f240 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff10038dcbe37
R13: 0000000000000006 R14: 0000000000000001 R15: 00000000000001b8
FS:  00007f21e0429700(0000) GS:ffff8801dc100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001ddbc22000 CR3: 00000001d632b000 CR4: 00000000001426e0
DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 refcount_dec_and_test+0x1a/0x20 lib/refcount.c:211
 in6_dev_put include/net/addrconf.h:335 [inline]
 ip6_route_dev_notify+0x1c9/0x4a0 net/ipv6/route.c:3732
 notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x51/0x90 net/core/dev.c:1678
 call_netdevice_notifiers net/core/dev.c:1694 [inline]
 rollback_registered_many+0x91c/0xe80 net/core/dev.c:7107
 rollback_registered+0x1be/0x3c0 net/core/dev.c:7149
 register_netdevice+0xbcd/0xee0 net/core/dev.c:7587
 register_netdev+0x1a/0x30 net/core/dev.c:7669
 loopback_net_init+0x76/0x160 drivers/net/loopback.c:214
 ops_init+0x10a/0x570 net/core/net_namespace.c:118
 setup_net+0x313/0x710 net/core/net_namespace.c:294
 copy_net_ns+0x27c/0x580 net/core/net_namespace.c:418
 create_new_namespaces+0x425/0x880 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xae/0x1e0 kernel/nsproxy.c:206
 SYSC_unshare kernel/fork.c:2347 [inline]
 SyS_unshare+0x653/0xfa0 kernel/fork.c:2297
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x4512c9
RSP: 002b:00007f21e0428c08 EFLAGS: 00000216 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 0000000000718150 RCX: 00000000004512c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000062020200
RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004b973d
R13: 00000000ffffffff R14: 000000002001d000 R15: 00000000000002dd
Code: 50 2b 34 82 c7 00 f1 f1 f1 f1 c7 40 04 04 f2 f2 f2 c7 40 08 f3 f3
f3 f3 e8 a1 43 39 ff 4c 89 f8 48 8b 95 70 ff ff ff 48 c1 e8 03 <0f> b6
0c 18 4c 89 f8 83 e0 07 83 c0 03 38 c8 7c 08 84 c9 0f 85
RIP: __read_once_size include/linux/compiler.h:250 [inline] RSP:
ffff8801c6e5f1b0
RIP: atomic_read arch/x86/include/asm/atomic.h:26 [inline] RSP:
ffff8801c6e5f1b0
RIP: refcount_sub_and_test+0x7d/0x1b0 lib/refcount.c:178 RSP:
ffff8801c6e5f1b0
---[ end trace e441d046c6410d31 ]---

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-15 17:06:34 -07:00
Reshetova, Elena
271201c09c net, ipv6: convert inet6_ifaddr.refcnt from atomic_t to refcount_t
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>
2017-07-04 01:29:04 -07:00
Reshetova, Elena
1be9246077 net, ipv6: convert inet6_dev.refcnt from atomic_t to refcount_t
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>
2017-07-04 01:29:04 -07:00
Krister Johansen
3ad7d2468f Ipvlan should return an error when an address is already in use.
The ipvlan code already knows how to detect when a duplicate address is
about to be assigned to an ipvlan device.  However, that failure is not
propogated outward and leads to a silent failure.

Introduce a validation step at ip address creation time and allow device
drivers to register to validate the incoming ip addresses.  The ipvlan
code is the first consumer.  If it detects an address in use, we can
return an error to the user before beginning to commit the new ifa in
the networking code.

This can be especially useful if it is necessary to provision many
ipvlans in containers.  The provisioning software (or operator) can use
this to detect situations where an ip address is unexpectedly in use.

Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-09 12:26:07 -04:00
WANG Cong
242d3a49a2 ipv6: reorder ip6_route_dev_notifier after ipv6_dev_notf
For each netns (except init_net), we initialize its null entry
in 3 places:

1) The template itself, as we use kmemdup()
2) Code around dst_init_metrics() in ip6_route_net_init()
3) ip6_route_dev_notify(), which is supposed to initialize it after
   loopback registers

Unfortunately the last one still happens in a wrong order because
we expect to initialize net->ipv6.ip6_null_entry->rt6i_idev to
net->loopback_dev's idev, thus we have to do that after we add
idev to loopback. However, this notifier has priority == 0 same as
ipv6_dev_notf, and ipv6_dev_notf is registered after
ip6_route_dev_notifier so it is called actually after
ip6_route_dev_notifier. This is similar to commit 2f460933f5
("ipv6: initialize route null entry in addrconf_init()") which
fixes init_net.

Fix it by picking a smaller priority for ip6_route_dev_notifier.
Also, we have to release the refcnt accordingly when unregistering
loopback_dev because device exit functions are called before subsys
exit functions.

Acked-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-08 17:31:24 -04:00
Yuval Shaia
4d6f28591f {net,IB}/{rxe,usnic}: Utilize generic mac to eui32 function
This logic seems to be duplicated in (at least) three separate files.
Move it to one place so code can be re-use.

Signed-off-by: Yuval Shaia <yuval.shaia@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
2017-04-25 14:21:34 -04:00
David Ahern
85b3daada4 net: ipv6: Refactor inet6_netconf_notify_devconf to take event
Refactor inet6_netconf_notify_devconf to take the event as an input arg.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-28 22:32:42 -07:00
Josef Bacik
fe38d2a1c8 inet: collapse ipv4/v6 rcv_saddr_equal functions into one
We pass these per-protocol equal functions around in various places, but
we can just have one function that checks the sk->sk_family and then do
the right comparison function.  I've also changed the ipv4 version to
not cast to inet_sock since it is unneeded.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-18 13:04:28 -05:00
WANG Cong
8651be8f14 ipv6: fix a potential deadlock in do_ipv6_setsockopt()
Baozeng reported this deadlock case:

       CPU0                    CPU1
       ----                    ----
  lock([  165.136033] sk_lock-AF_INET6);
                               lock([  165.136033] rtnl_mutex);
                               lock([  165.136033] sk_lock-AF_INET6);
  lock([  165.136033] rtnl_mutex);

Similar to commit 87e9f03159
("ipv4: fix a potential deadlock in mcast getsockopt() path")
this is due to we still have a case, ipv6_sock_mc_close(),
where we acquire sk_lock before rtnl_lock. Close this deadlock
with the similar solution, that is always acquire rtnl lock first.

Fixes: baf606d9c9 ("ipv4,ipv6: grab rtnl before locking the socket")
Reported-by: Baozeng Ding <sploving1@gmail.com>
Tested-by: Baozeng Ding <sploving1@gmail.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-21 11:29:02 -04:00
Maciej Żenczykowski
bd11f0741f ipv6 addrconf: implement RFC7559 router solicitation backoff
This implements:
  https://tools.ietf.org/html/rfc7559

Backoff is performed according to RFC3315 section 14:
  https://tools.ietf.org/html/rfc3315#section-14

We allow setting /proc/sys/net/ipv6/conf/*/router_solicitations
to a negative value meaning an unlimited number of retransmits,
and we make this the new default (inline with the RFC).

We also add a new setting:
  /proc/sys/net/ipv6/conf/*/router_solicitation_max_interval
defaulting to 1 hour (per RFC recommendation).

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Acked-by: Erik Kline <ek@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30 01:54:28 -04:00
Alexander Aring
cc84b3c6b4 ipv6: export several functions
This patch exports some neighbour discovery functions which can be used
by 6lowpan neighbour discovery ops functionality then.

Cc: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-15 20:41:23 -07:00
Alexander Aring
2ad3ed5919 6lowpan: add 802.15.4 short addr slaac
This patch adds the autoconfiguration if a valid 802.15.4 short address
is available for 802.15.4 6LoWPAN interfaces.

Cc: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-15 20:41:22 -07:00
Craig Gallek
a583636a83 inet: refactor inet[6]_lookup functions to take skb
This is a preliminary step to allow fast socket lookup of SO_REUSEPORT
groups.  Doing so with a BPF filter will require access to the
skb in question.  This change plumbs the skb (and offset to payload
data) through the call stack to the listening socket lookup
implementations where it will be used in a following patch.

Signed-off-by: Craig Gallek <kraig@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11 03:54:14 -05:00