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6828 commits

Author SHA1 Message Date
Maciej Żenczykowski 82f31ebf61 net: port < inet_prot_sock(net) --> inet_port_requires_bind_service(net, port)
Note that the sysctl write accessor functions guarantee that:
  net->ipv4.sysctl_ip_prot_sock <= net->ipv4.ip_local_ports.range[0]
invariant is maintained, and as such the max() in selinux hooks is actually spurious.

ie. even though
  if (snum < max(inet_prot_sock(sock_net(sk)), low) || snum > high) {
per logic is the same as
  if ((snum < inet_prot_sock(sock_net(sk)) && snum < low) || snum > high) {
it is actually functionally equivalent to:
  if (snum < low || snum > high) {
which is equivalent to:
  if (snum < inet_prot_sock(sock_net(sk)) || snum < low || snum > high) {
even though the first clause is spurious.

But we want to hold on to it in case we ever want to change what what
inet_port_requires_bind_service() means (for example by changing
it from a, by default, [0..1024) range to some sort of set).

Test: builds, git 'grep inet_prot_sock' finds no other references
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-26 13:20:46 -08:00
Jakub Kicinski a9f852e92e Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Minor conflict in drivers/s390/net/qeth_l2_main.c, kept the lock
from commit c8183f5489 ("s390/qeth: fix potential deadlock on
workqueue flush"), removed the code which was removed by commit
9897d583b0 ("s390/qeth: consolidate some duplicated HW cmd code").

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-11-22 16:27:24 -08:00
Andrea Mayer fd1fef0c45 seg6: allow local packet processing for SRv6 End.DT6 behavior
End.DT6 behavior makes use of seg6_lookup_nexthop() function which drops
all packets that are destined to be locally processed. However, DT* should
be able to deliver decapsulated packets that are destined to local
addresses. Function seg6_lookup_nexthop() is also used by DX6, so in order
to maintain compatibility I created another routing helper function which
is called seg6_lookup_any_nexthop(). This function is able to take into
account both packets that have to be processed locally and the ones that
are destined to be forwarded directly to another machine. Hence,
seg6_lookup_any_nexthop() is used in DT6 rather than seg6_lookup_nexthop()
to allow local delivery.

Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-22 09:45:55 -08:00
Maciej Żenczykowski 35fc59c956 net-ipv6: IPV6_TRANSPARENT - check NET_RAW prior to NET_ADMIN
NET_RAW is less dangerous, so more likely to be available to a process,
so check it first to prevent some spurious logging.

This matches IP_TRANSPARENT which checks NET_RAW first.

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-21 19:15:20 -08:00
Paolo Abeni 197dbf24e3 ipv6: introduce and uses route look hints for list input.
When doing RX batch packet processing, we currently always repeat
the route lookup for each ingress packet. When no custom rules are
in place, and there aren't routes depending on source addresses,
we know that packets with the same destination address will use
the same dst.

This change tries to avoid per packet route lookup caching
the destination address of the latest successful lookup, and
reusing it for the next packet when the above conditions are
in place. Ingress traffic for most servers should fit.

The measured performance delta under UDP flood vs a recvmmsg
receiver is as follow:

vanilla		patched		delta
Kpps		Kpps		%
1431		1674		+17

In the worst-case scenario - each packet has a different
destination address - the performance delta is within noise
range.

v3 -> v4:
 - support hints for SUBFLOW build, too (David A.)
 - several style fixes (Eric)

v2 -> v3:
 - add fib6_has_custom_rules() helpers (David A.)
 - add ip6_extract_route_hint() helper (Edward C.)
 - use hint directly in ip6_list_rcv_finish() (Willem)

v1 -> v2:
 - fix build issue with !CONFIG_IPV6_MULTIPLE_TABLES
 - fix potential race when fib6_has_custom_rules is set
   while processing a packet batch

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-21 14:45:55 -08:00
Paolo Abeni b9b33e7c24 ipv6: keep track of routes using src
Use a per namespace counter, increment it on successful creation
of any route using the source address, decrement it on deletion
of such routes.

This allows us to check easily if the routing decision in the
current namespace depends on the packet source. Will be used
by the next patch.

Suggested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-21 14:45:55 -08:00
Krzysztof Kozlowski 43da14110c net: Fix Kconfig indentation, continued
Adjust indentation from spaces to tab (+optional two spaces) as in
coding style.  This fixes various indentation mixups (seven spaces,
tab+one space, etc).

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-21 12:00:21 -08:00
Hangbin Liu 004b39427f ipv6/route: return if there is no fib_nh_gw_family
Previously we will return directly if (!rt || !rt->fib6_nh.fib_nh_gw_family)
in function rt6_probe(), but after commit cc3a86c802
("ipv6: Change rt6_probe to take a fib6_nh"), the logic changed to
return if there is fib_nh_gw_family.

Fixes: cc3a86c802 ("ipv6: Change rt6_probe to take a fib6_nh")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-20 12:17:39 -08:00
David S. Miller 99638e9d6c Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

1) Wildcard support for the net,iface set from Kristian Evensen.

2) Offload support for matching on the input interface.

3) Simplify matching on vlan header fields.

4) Add nft_payload_rebuild_vlan_hdr() function to rebuild the vlan
   header from the vlan sk_buff metadata.

5) Pass extack to nft_flow_cls_offload_setup().

6) Add C-VLAN matching support.

7) Use time64_t in xt_time to fix y2038 overflow, from Arnd Bergmann.

8) Use time_t in nft_meta to fix y2038 overflow, also from Arnd.

9) Add flow_action_entry_next() helper function to flowtable offload
   infrastructure.

10) Add IPv6 support to the flowtable offload infrastructure.

11) Support for input interface matching from postrouting,
    from Phil Sutter.

12) Missing check for ndo callback in flowtable offload, from wenxu.

13) Remove conntrack parameter from flow_offload_fill_dir(), from wenxu.

14) Do not pass flow_rule object for rule removal, cookie is sufficient
    to achieve this.

15) Release flow_rule object in case of error from the offload commit
    path.

16) Undo offload ruleset updates if transaction fails.

17) Check for error when binding flowtable callbacks, from wenxu.

18) Always unbind flowtable callbacks when unregistering hooks.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-18 16:43:05 -08:00
David S. Miller 19b7e21c55 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Lots of overlapping changes and parallel additions, stuff
like that.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-16 21:51:42 -08:00
Andrea Mayer c71644d00f seg6: fix skb transport_header after decap_and_validate()
in the receive path (more precisely in ip6_rcv_core()) the
skb->transport_header is set to skb->network_header + sizeof(*hdr). As a
consequence, after routing operations, destination input expects to find
skb->transport_header correctly set to the next protocol (or extension
header) that follows the network protocol. However, decap behaviors (DX*,
DT*) remove the outer IPv6 and SRH extension and do not set again the
skb->transport_header pointer correctly. For this reason, the patch sets
the skb->transport_header to the skb->network_header + sizeof(hdr) in each
DX* and DT* behavior.

Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-16 12:18:32 -08:00
Andrea Mayer 7f91ed8c4f seg6: fix srh pointer in get_srh()
pskb_may_pull may change pointers in header. For this reason, it is
mandatory to reload any pointer that points into skb header.

Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-16 12:18:32 -08:00
Phil Sutter 28f8bfd1ac netfilter: Support iif matches in POSTROUTING
Instead of generally passing NULL to NF_HOOK_COND() for input device,
pass skb->dev which contains input device for routed skbs.

Note that iptables (both legacy and nft) reject rules with input
interface match from being added to POSTROUTING chains, but nftables
allows this.

Cc: Eric Garver <eric@garver.life>
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-11-15 23:44:48 +01:00
Pablo Neira Ayuso 5c27d8d76c netfilter: nf_flow_table_offload: add IPv6 support
Add nf_flow_rule_route_ipv6() and use it from the IPv6 and the inet
flowtable type definitions. Rename the nf_flow_rule_route() function to
nf_flow_rule_route_ipv4().

Adjust maximum number of actions, which now becomes 16 to leave
sufficient room for the IPv6 address mangling for NAT.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-11-15 23:44:47 +01:00
Pablo Neira Ayuso c29f74e0df netfilter: nf_flow_table: hardware offload support
This patch adds the dataplane hardware offload to the flowtable
infrastructure. Three new flags represent the hardware state of this
flow:

* FLOW_OFFLOAD_HW: This flow entry resides in the hardware.
* FLOW_OFFLOAD_HW_DYING: This flow entry has been scheduled to be remove
  from hardware. This might be triggered by either packet path (via TCP
  RST/FIN packet) or via aging.
* FLOW_OFFLOAD_HW_DEAD: This flow entry has been already removed from
  the hardware, the software garbage collector can remove it from the
  software flowtable.

This patch supports for:

* IPv4 only.
* Aging via FLOW_CLS_STATS, no packet and byte counter synchronization
  at this stage.

This patch also adds the action callback that specifies how to convert
the flow entry into the flow_rule object that is passed to the driver.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-12 19:42:26 -08:00
Pablo Neira Ayuso 8bb69f3b29 netfilter: nf_tables: add flowtable offload control plane
This patch adds the NFTA_FLOWTABLE_FLAGS attribute that allows users to
specify the NF_FLOWTABLE_HW_OFFLOAD flag. This patch also adds a new
setup interface for the flowtable type to perform the flowtable offload
block callback configuration.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-12 19:42:26 -08:00
David S. Miller 14684b9301 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
One conflict in the BPF samples Makefile, some fixes in 'net' whilst
we were converting over to Makefile.target rules in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-09 11:04:37 -08:00
Eric Dumazet 1bef4c223b ipv6: fixes rt6_probe() and fib6_nh->last_probe init
While looking at a syzbot KCSAN report [1], I found multiple
issues in this code :

1) fib6_nh->last_probe has an initial value of 0.

   While probably okay on 64bit kernels, this causes an issue
   on 32bit kernels since the time_after(jiffies, 0 + interval)
   might be false ~24 days after boot (for HZ=1000)

2) The data-race found by KCSAN
   I could use READ_ONCE() and WRITE_ONCE(), but we also can
   take the opportunity of not piling-up too many rt6_probe_deferred()
   works by using instead cmpxchg() so that only one cpu wins the race.

[1]
BUG: KCSAN: data-race in find_match / find_match

write to 0xffff8880bb7aabe8 of 8 bytes by interrupt on cpu 1:
 rt6_probe net/ipv6/route.c:663 [inline]
 find_match net/ipv6/route.c:757 [inline]
 find_match+0x5bd/0x790 net/ipv6/route.c:733
 __find_rr_leaf+0xe3/0x780 net/ipv6/route.c:831
 find_rr_leaf net/ipv6/route.c:852 [inline]
 rt6_select net/ipv6/route.c:896 [inline]
 fib6_table_lookup+0x383/0x650 net/ipv6/route.c:2164
 ip6_pol_route+0xee/0x5c0 net/ipv6/route.c:2200
 ip6_pol_route_output+0x48/0x60 net/ipv6/route.c:2452
 fib6_rule_lookup+0x3d6/0x470 net/ipv6/fib6_rules.c:117
 ip6_route_output_flags_noref+0x16b/0x230 net/ipv6/route.c:2484
 ip6_route_output_flags+0x50/0x1a0 net/ipv6/route.c:2497
 ip6_dst_lookup_tail+0x25d/0xc30 net/ipv6/ip6_output.c:1049
 ip6_dst_lookup_flow+0x68/0x120 net/ipv6/ip6_output.c:1150
 inet6_csk_route_socket+0x2f7/0x420 net/ipv6/inet6_connection_sock.c:106
 inet6_csk_xmit+0x91/0x1f0 net/ipv6/inet6_connection_sock.c:121
 __tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169
 tcp_transmit_skb net/ipv4/tcp_output.c:1185 [inline]
 tcp_xmit_probe_skb+0x19b/0x1d0 net/ipv4/tcp_output.c:3735

read to 0xffff8880bb7aabe8 of 8 bytes by interrupt on cpu 0:
 rt6_probe net/ipv6/route.c:657 [inline]
 find_match net/ipv6/route.c:757 [inline]
 find_match+0x521/0x790 net/ipv6/route.c:733
 __find_rr_leaf+0xe3/0x780 net/ipv6/route.c:831
 find_rr_leaf net/ipv6/route.c:852 [inline]
 rt6_select net/ipv6/route.c:896 [inline]
 fib6_table_lookup+0x383/0x650 net/ipv6/route.c:2164
 ip6_pol_route+0xee/0x5c0 net/ipv6/route.c:2200
 ip6_pol_route_output+0x48/0x60 net/ipv6/route.c:2452
 fib6_rule_lookup+0x3d6/0x470 net/ipv6/fib6_rules.c:117
 ip6_route_output_flags_noref+0x16b/0x230 net/ipv6/route.c:2484
 ip6_route_output_flags+0x50/0x1a0 net/ipv6/route.c:2497
 ip6_dst_lookup_tail+0x25d/0xc30 net/ipv6/ip6_output.c:1049
 ip6_dst_lookup_flow+0x68/0x120 net/ipv6/ip6_output.c:1150
 inet6_csk_route_socket+0x2f7/0x420 net/ipv6/inet6_connection_sock.c:106
 inet6_csk_xmit+0x91/0x1f0 net/ipv6/inet6_connection_sock.c:121
 __tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 18894 Comm: udevd Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: cc3a86c802 ("ipv6: Change rt6_probe to take a fib6_nh")
Fixes: f547fac624 ("ipv6: rate-limit probes for neighbourless routes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-07 16:13:13 -08:00
Eric Dumazet 288efe8606 net: annotate lockless accesses to sk->sk_ack_backlog
sk->sk_ack_backlog can be read without any lock being held.
We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing
and/or potential KCSAN warnings.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-06 16:14:48 -08:00
Matteo Croce 54074f1dbd icmp: remove duplicate code
The same code which recognizes ICMP error packets is duplicated several
times. Use the icmp_is_err() and icmpv6_is_err() helpers instead, which
do the same thing.

ip_multipath_l3_keys() and tcf_nat_act() didn't check for all the error types,
assume that they should instead.

Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-05 14:03:11 -08:00
Eric Dumazet b6b556afd2 ipv6: use jhash2() in rt6_exception_hash()
Faster jhash2() can be used instead of jhash(), since
IPv6 addresses have the needed alignment requirement.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-04 11:28:49 -08:00
Francesco Ruggeri fac6fce9bd net: icmp6: provide input address for traceroute6
traceroute6 output can be confusing, in that it shows the address
that a router would use to reach the sender, rather than the address
the packet used to reach the router.
Consider this case:

        ------------------------ N2
         |                    |
       ------              ------  N3  ----
       | R1 |              | R2 |------|H2|
       ------              ------      ----
         |                    |
        ------------------------ N1
                  |
                 ----
                 |H1|
                 ----

where H1's default route is through R1, and R1's default route is
through R2 over N2.
traceroute6 from H1 to H2 shows R2's address on N1 rather than on N2.

The script below can be used to reproduce this scenario.

traceroute6 output without this patch:

traceroute to 2000:103::4 (2000:103::4), 30 hops max, 80 byte packets
 1  2000:101::1 (2000:101::1)  0.036 ms  0.008 ms  0.006 ms
 2  2000:101::2 (2000:101::2)  0.011 ms  0.008 ms  0.007 ms
 3  2000:103::4 (2000:103::4)  0.013 ms  0.010 ms  0.009 ms

traceroute6 output with this patch:

traceroute to 2000:103::4 (2000:103::4), 30 hops max, 80 byte packets
 1  2000:101::1 (2000:101::1)  0.056 ms  0.019 ms  0.006 ms
 2  2000:102::2 (2000:102::2)  0.013 ms  0.008 ms  0.008 ms
 3  2000:103::4 (2000:103::4)  0.013 ms  0.009 ms  0.009 ms

#!/bin/bash
#
#        ------------------------ N2
#         |                    |
#       ------              ------  N3  ----
#       | R1 |              | R2 |------|H2|
#       ------              ------      ----
#         |                    |
#        ------------------------ N1
#                  |
#                 ----
#                 |H1|
#                 ----
#
# N1: 2000:101::/64
# N2: 2000:102::/64
# N3: 2000:103::/64
#
# R1's host part of address: 1
# R2's host part of address: 2
# H1's host part of address: 3
# H2's host part of address: 4
#
# For example:
# the IPv6 address of R1's interface on N2 is 2000:102::1/64
#
# Nets are implemented by macvlan interfaces (bridge mode) over
# dummy interfaces.
#

# Create net namespaces
ip netns add host1
ip netns add host2
ip netns add rtr1
ip netns add rtr2

# Create nets
ip link add net1 type dummy; ip link set net1 up
ip link add net2 type dummy; ip link set net2 up
ip link add net3 type dummy; ip link set net3 up

# Add interfaces to net1, move them to their nemaspaces
ip link add link net1 dev host1net1 type macvlan mode bridge
ip link set host1net1 netns host1
ip link add link net1 dev rtr1net1 type macvlan mode bridge
ip link set rtr1net1 netns rtr1
ip link add link net1 dev rtr2net1 type macvlan mode bridge
ip link set rtr2net1 netns rtr2

# Add interfaces to net2, move them to their nemaspaces
ip link add link net2 dev rtr1net2 type macvlan mode bridge
ip link set rtr1net2 netns rtr1
ip link add link net2 dev rtr2net2 type macvlan mode bridge
ip link set rtr2net2 netns rtr2

# Add interfaces to net3, move them to their nemaspaces
ip link add link net3 dev rtr2net3 type macvlan mode bridge
ip link set rtr2net3 netns rtr2
ip link add link net3 dev host2net3 type macvlan mode bridge
ip link set host2net3 netns host2

# Configure interfaces and routes in host1
ip netns exec host1 ip link set lo up
ip netns exec host1 ip link set host1net1 up
ip netns exec host1 ip -6 addr add 2000:101::3/64 dev host1net1
ip netns exec host1 ip -6 route add default via 2000:101::1

# Configure interfaces and routes in rtr1
ip netns exec rtr1 ip link set lo up
ip netns exec rtr1 ip link set rtr1net1 up
ip netns exec rtr1 ip -6 addr add 2000:101::1/64 dev rtr1net1
ip netns exec rtr1 ip link set rtr1net2 up
ip netns exec rtr1 ip -6 addr add 2000:102::1/64 dev rtr1net2
ip netns exec rtr1 ip -6 route add default via 2000:102::2
ip netns exec rtr1 sysctl net.ipv6.conf.all.forwarding=1

# Configure interfaces and routes in rtr2
ip netns exec rtr2 ip link set lo up
ip netns exec rtr2 ip link set rtr2net1 up
ip netns exec rtr2 ip -6 addr add 2000:101::2/64 dev rtr2net1
ip netns exec rtr2 ip link set rtr2net2 up
ip netns exec rtr2 ip -6 addr add 2000:102::2/64 dev rtr2net2
ip netns exec rtr2 ip link set rtr2net3 up
ip netns exec rtr2 ip -6 addr add 2000:103::2/64 dev rtr2net3
ip netns exec rtr2 sysctl net.ipv6.conf.all.forwarding=1

# Configure interfaces and routes in host2
ip netns exec host2 ip link set lo up
ip netns exec host2 ip link set host2net3 up
ip netns exec host2 ip -6 addr add 2000:103::4/64 dev host2net3
ip netns exec host2 ip -6 route add default via 2000:103::2

# Ping host2 from host1
ip netns exec host1 ping6 -c5 2000:103::4

# Traceroute host2 from host1
ip netns exec host1 traceroute6 2000:103::4

# Delete nets
ip link del net3
ip link del net2
ip link del net1

# Delete namespaces
ip netns del rtr2
ip netns del rtr1
ip netns del host2
ip netns del host1

Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Original-patch-by: Honggang Xu <hxu@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-03 17:26:53 -08:00
David S. Miller d31e95585c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
The only slightly tricky merge conflict was the netdevsim because the
mutex locking fix overlapped a lot of driver reload reorganization.

The rest were (relatively) trivial in nature.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-02 13:54:56 -07:00
Eric Dumazet 7170a97774 net: annotate accesses to sk->sk_incoming_cpu
This socket field can be read and written by concurrent cpus.

Use READ_ONCE() and WRITE_ONCE() annotations to document this,
and avoid some compiler 'optimizations'.

KCSAN reported :

BUG: KCSAN: data-race in tcp_v4_rcv / tcp_v4_rcv

write to 0xffff88812220763c of 4 bytes by interrupt on cpu 0:
 sk_incoming_cpu_update include/net/sock.h:953 [inline]
 tcp_v4_rcv+0x1b3c/0x1bb0 net/ipv4/tcp_ipv4.c:1934
 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:442 [inline]
 ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124
 process_backlog+0x1d3/0x420 net/core/dev.c:5955
 napi_poll net/core/dev.c:6392 [inline]
 net_rx_action+0x3ae/0xa90 net/core/dev.c:6460
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082
 do_softirq.part.0+0x6b/0x80 kernel/softirq.c:337
 do_softirq kernel/softirq.c:329 [inline]
 __local_bh_enable_ip+0x76/0x80 kernel/softirq.c:189

read to 0xffff88812220763c of 4 bytes by interrupt on cpu 1:
 sk_incoming_cpu_update include/net/sock.h:952 [inline]
 tcp_v4_rcv+0x181a/0x1bb0 net/ipv4/tcp_ipv4.c:1934
 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:442 [inline]
 ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124
 process_backlog+0x1d3/0x420 net/core/dev.c:5955
 napi_poll net/core/dev.c:6392 [inline]
 net_rx_action+0x3ae/0xa90 net/core/dev.c:6460
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 run_ksoftirqd+0x46/0x60 kernel/softirq.c:603
 smpboot_thread_fn+0x37d/0x4a0 kernel/smpboot.c:165

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30 13:24:25 -07:00
Florian Westphal 51210ad5a5 inet: do not call sublist_rcv on empty list
syzbot triggered struct net NULL deref in NF_HOOK_LIST:
RIP: 0010:NF_HOOK_LIST include/linux/netfilter.h:331 [inline]
RIP: 0010:ip6_sublist_rcv+0x5c9/0x930 net/ipv6/ip6_input.c:292
 ipv6_list_rcv+0x373/0x4b0 net/ipv6/ip6_input.c:328
 __netif_receive_skb_list_ptype net/core/dev.c:5274 [inline]

Reason:
void ipv6_list_rcv(struct list_head *head, struct packet_type *pt,
                   struct net_device *orig_dev)
[..]
        list_for_each_entry_safe(skb, next, head, list) {
		/* iterates list */
                skb = ip6_rcv_core(skb, dev, net);
		/* ip6_rcv_core drops skb -> NULL is returned */
                if (skb == NULL)
                        continue;
	[..]
	}
	/* sublist is empty -> curr_net is NULL */
        ip6_sublist_rcv(&sublist, curr_dev, curr_net);

Before the recent change NF_HOOK_LIST did a list iteration before
struct net deref, i.e. it was a no-op in the empty list case.

List iteration now happens after *net deref, causing crash.

Follow the same pattern as the ip(v6)_list_rcv loop and add a list_empty
test for the final sublist dispatch too.

Cc: Edward Cree <ecree@solarflare.com>
Reported-by: syzbot+c54f457cad330e57e967@syzkaller.appspotmail.com
Fixes: ca58fbe06c ("netfilter: add and use nf_hook_slow_list()")
Signed-off-by: Florian Westphal <fw@strlen.de>
Tested-by: Leon Romanovsky <leonro@mellanox.com>
Tested-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-29 17:54:29 -07:00
Xin Long 2eb8d6d291 erspan: fix the tun_info options_len check for erspan
The check for !md doens't really work for ip_tunnel_info_opts(info) which
only does info + 1. Also to avoid out-of-bounds access on info, it should
ensure options_len is not less than erspan_metadata in both erspan_xmit()
and ip6erspan_tunnel_xmit().

Fixes: 1a66a836da ("gre: add collect_md mode to ERSPAN tunnel")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-29 17:36:42 -07:00
David S. Miller 4b1f5ddaff Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter/IPVS updates for net-next,
more specifically:

* Updates for ipset:

1) Coding style fix for ipset comment extension, from Jeremy Sowden.

2) De-inline many functions in ipset, from Jeremy Sowden.

3) Move ipset function definition from header to source file.

4) Move ip_set_put_flags() to source, export it as a symbol, remove
   inline.

5) Move range_to_mask() to the source file where this is used.

6) Move ip_set_get_ip_port() to the source file where this is used.

* IPVS selftests and netns improvements:

7) Two patches to speedup ipvs netns dismantle, from Haishuang Yan.

8) Three patches to add selftest script for ipvs, also from
   Haishuang Yan.

* Conntrack updates and new nf_hook_slow_list() function:

9) Document ct ecache extension, from Florian Westphal.

10) Skip ct extensions from ctnetlink dump, from Florian.

11) Free ct extension immediately, from Florian.

12) Skip access to ecache extension from nf_ct_deliver_cached_events()
    this is not correct as reported by Syzbot.

13) Add and use nf_hook_slow_list(), from Florian.

* Flowtable infrastructure updates:

14) Move priority to nf_flowtable definition.

15) Dynamic allocation of per-device hooks in flowtables.

16) Allow to include netdevice only once in flowtable definitions.

17) Rise maximum number of devices per flowtable.

* Netfilter hardware offload infrastructure updates:

18) Add nft_flow_block_chain() helper function.

19) Pass callback list to nft_setup_cb_call().

20) Add nft_flow_cls_offload_setup() helper function.

21) Remove rules for the unregistered device via netdevice event.

22) Support for multiple devices in a basechain definition at the
    ingress hook.

22) Add nft_chain_offload_cmd() helper function.

23) Add nft_flow_block_offload_init() helper function.

24) Rewind in case of failing to bind multiple devices to hook.

25) Typo in IPv6 tproxy module description, from Norman Rasmussen.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-26 11:35:43 -07:00
Ben Dooks (Codethink) 6c5d9c2a6b ipv6: include <net/addrconf.h> for missing declarations
Include <net/addrconf.h> for the missing declarations of
various functions. Fixes the following sparse warnings:

net/ipv6/addrconf_core.c:94:5: warning: symbol 'register_inet6addr_notifier' was not declared. Should it be static?
net/ipv6/addrconf_core.c💯5: warning: symbol 'unregister_inet6addr_notifier' was not declared. Should it be static?
net/ipv6/addrconf_core.c:106:5: warning: symbol 'inet6addr_notifier_call_chain' was not declared. Should it be static?
net/ipv6/addrconf_core.c:112:5: warning: symbol 'register_inet6addr_validator_notifier' was not declared. Should it be static?
net/ipv6/addrconf_core.c:118:5: warning: symbol 'unregister_inet6addr_validator_notifier' was not declared. Should it be static?
net/ipv6/addrconf_core.c:125:5: warning: symbol 'inet6addr_validator_notifier_call_chain' was not declared. Should it be static?
net/ipv6/addrconf_core.c:237:6: warning: symbol 'in6_dev_finish_destroy' was not declared. Should it be static?

Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-22 15:17:03 -07:00
David S. Miller 2f184393e0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Several cases of overlapping changes which were for the most
part trivially resolvable.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-20 10:43:00 -07:00
Eric Dumazet 9669fffc14 net: ensure correct skb->tstamp in various fragmenters
Thomas found that some forwarded packets would be stuck
in FQ packet scheduler because their skb->tstamp contained
timestamps far in the future.

We thought we addressed this point in commit 8203e2d844
("net: clear skb->tstamp in forwarding paths") but there
is still an issue when/if a packet needs to be fragmented.

In order to meet EDT requirements, we have to make sure all
fragments get the original skb->tstamp.

Note that this original skb->tstamp should be zero in
forwarding path, but might have a non zero value in
output path if user decided so.

Fixes: fb420d5d91 ("tcp/fq: move back to CLOCK_MONOTONIC")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Thomas Bartschies <Thomas.Bartschies@cvk.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-18 10:02:37 -07:00
Norman Rasmussen 0a9b338500 netfilter: nft_tproxy: Fix typo in IPv6 module description.
Signed-off-by: Norman Rasmussen <norman@rasmussen.co.za>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-10-17 12:21:11 +02:00
Mahesh Bandewar bd74708cd9 Revert "blackhole_netdev: fix syzkaller reported issue"
This reverts commit b0818f80c8.

Started seeing weird behavior after this patch especially in
the IPv6 code path. Haven't root caused it, but since this was
applied to net branch, taking a precautionary measure to revert
it and look / analyze those failures

Revert this now and I'll send a better fix after analysing / fixing
the weirdness observed.

CC: Eric Dumazet <edumazet@google.com>
CC: Wei Wang <weiwan@google.com>
CC: David S. Miller <davem@davemloft.net>
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-16 13:41:26 -04:00
Mahesh Bandewar b0818f80c8 blackhole_netdev: fix syzkaller reported issue
While invalidating the dst, we assign backhole_netdev instead of
loopback device. However, this device does not have idev pointer
and hence no ip6_ptr even if IPv6 is enabled. Possibly this has
triggered the syzbot reported crash.

The syzbot report does not have reproducer, however, this is the
only device that doesn't have matching idev created.

Crash instruction is :

static inline bool ip6_ignore_linkdown(const struct net_device *dev)
{
        const struct inet6_dev *idev = __in6_dev_get(dev);

        return !!idev->cnf.ignore_routes_with_linkdown; <= crash
}

Also ipv6 always assumes presence of idev and never checks for it
being NULL (as does the above referenced code). So adding a idev
for the blackhole_netdev to avoid this class of crashes in the future.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15 10:35:23 -07:00
Eric Dumazet 0f31746452 tcp: annotate tp->write_seq lockless reads
There are few places where we fetch tp->write_seq while
this field can change from IRQ or other cpu.

We need to add READ_ONCE() annotations, and also make
sure write sides use corresponding WRITE_ONCE() to avoid
store-tearing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13 10:13:08 -07:00
Eric Dumazet 7db48e9839 tcp: annotate tp->copied_seq lockless reads
There are few places where we fetch tp->copied_seq while
this field can change from IRQ or other cpu.

We need to add READ_ONCE() annotations, and also make
sure write sides use corresponding WRITE_ONCE() to avoid
store-tearing.

Note that tcp_inq_hint() was already using READ_ONCE(tp->copied_seq)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13 10:13:08 -07:00
Eric Dumazet dba7d9b8c7 tcp: annotate tp->rcv_nxt lockless reads
There are few places where we fetch tp->rcv_nxt while
this field can change from IRQ or other cpu.

We need to add READ_ONCE() annotations, and also make
sure write sides use corresponding WRITE_ONCE() to avoid
store-tearing.

Note that tcp_inq_hint() was already using READ_ONCE(tp->rcv_nxt)

syzbot reported :

BUG: KCSAN: data-race in tcp_poll / tcp_queue_rcv

write to 0xffff888120425770 of 4 bytes by interrupt on cpu 0:
 tcp_rcv_nxt_update net/ipv4/tcp_input.c:3365 [inline]
 tcp_queue_rcv+0x180/0x380 net/ipv4/tcp_input.c:4638
 tcp_rcv_established+0xbf1/0xf50 net/ipv4/tcp_input.c:5616
 tcp_v4_do_rcv+0x381/0x4e0 net/ipv4/tcp_ipv4.c:1542
 tcp_v4_rcv+0x1a03/0x1bf0 net/ipv4/tcp_ipv4.c:1923
 ip_protocol_deliver_rcu+0x51/0x470 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:442 [inline]
 ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413
 NF_HOOK include/linux/netfilter.h:305 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523
 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5004
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118
 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208
 napi_skb_finish net/core/dev.c:5671 [inline]
 napi_gro_receive+0x28f/0x330 net/core/dev.c:5704
 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061

read to 0xffff888120425770 of 4 bytes by task 7254 on cpu 1:
 tcp_stream_is_readable net/ipv4/tcp.c:480 [inline]
 tcp_poll+0x204/0x6b0 net/ipv4/tcp.c:554
 sock_poll+0xed/0x250 net/socket.c:1256
 vfs_poll include/linux/poll.h:90 [inline]
 ep_item_poll.isra.0+0x90/0x190 fs/eventpoll.c:892
 ep_send_events_proc+0x113/0x5c0 fs/eventpoll.c:1749
 ep_scan_ready_list.constprop.0+0x189/0x500 fs/eventpoll.c:704
 ep_send_events fs/eventpoll.c:1793 [inline]
 ep_poll+0xe3/0x900 fs/eventpoll.c:1930
 do_epoll_wait+0x162/0x180 fs/eventpoll.c:2294
 __do_sys_epoll_pwait fs/eventpoll.c:2325 [inline]
 __se_sys_epoll_pwait fs/eventpoll.c:2311 [inline]
 __x64_sys_epoll_pwait+0xcd/0x170 fs/eventpoll.c:2311
 do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7254 Comm: syz-fuzzer Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13 10:13:08 -07:00
Eric Dumazet d983ea6f16 tcp: add rcu protection around tp->fastopen_rsk
Both tcp_v4_err() and tcp_v6_err() do the following operations
while they do not own the socket lock :

	fastopen = tp->fastopen_rsk;
 	snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una;

The problem is that without appropriate barrier, the compiler
might reload tp->fastopen_rsk and trigger a NULL deref.

request sockets are protected by RCU, we can simply add
the missing annotations and barriers to solve the issue.

Fixes: 168a8f5805 ("tcp: TCP Fast Open Server - main code path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-13 10:13:08 -07:00
Haishuang Yan 4123f637a5 ip6erspan: remove the incorrect mtu limit for ip6erspan
ip6erspan driver calls ether_setup(), after commit 61e84623ac
("net: centralize net_device min/max MTU checking"), the range
of mtu is [min_mtu, max_mtu], which is [68, 1500] by default.

It causes the dev mtu of the erspan device to not be greater
than 1500, this limit value is not correct for ip6erspan tap
device.

Fixes: 61e84623ac ("net: centralize net_device min/max MTU checking")
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-08 19:46:42 -07:00
David S. Miller 6f4c930e02 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-10-05 13:37:23 -07:00
David Ahern 2d819d250a ipv6: Handle missing host route in __ipv6_ifa_notify
Rajendra reported a kernel panic when a link was taken down:

    [ 6870.263084] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8
    [ 6870.271856] IP: [<ffffffff8efc5764>] __ipv6_ifa_notify+0x154/0x290

    <snip>

    [ 6870.570501] Call Trace:
    [ 6870.573238] [<ffffffff8efc58c6>] ? ipv6_ifa_notify+0x26/0x40
    [ 6870.579665] [<ffffffff8efc98ec>] ? addrconf_dad_completed+0x4c/0x2c0
    [ 6870.586869] [<ffffffff8efe70c6>] ? ipv6_dev_mc_inc+0x196/0x260
    [ 6870.593491] [<ffffffff8efc9c6a>] ? addrconf_dad_work+0x10a/0x430
    [ 6870.600305] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70
    [ 6870.606732] [<ffffffff8ea93a7a>] ? process_one_work+0x18a/0x430
    [ 6870.613449] [<ffffffff8ea93d6d>] ? worker_thread+0x4d/0x490
    [ 6870.619778] [<ffffffff8ea93d20>] ? process_one_work+0x430/0x430
    [ 6870.626495] [<ffffffff8ea99dd9>] ? kthread+0xd9/0xf0
    [ 6870.632145] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70
    [ 6870.638573] [<ffffffff8ea99d00>] ? kthread_park+0x60/0x60
    [ 6870.644707] [<ffffffff8f01ae77>] ? ret_from_fork+0x57/0x70
    [ 6870.650936] Code: 31 c0 31 d2 41 b9 20 00 08 02 b9 09 00 00 0

addrconf_dad_work is kicked to be scheduled when a device is brought
up. There is a race between addrcond_dad_work getting scheduled and
taking the rtnl lock and a process taking the link down (under rtnl).
The latter removes the host route from the inet6_addr as part of
addrconf_ifdown which is run for NETDEV_DOWN. The former attempts
to use the host route in __ipv6_ifa_notify. If the down event removes
the host route due to the race to the rtnl, then the BUG listed above
occurs.

Since the DAD sequence can not be aborted, add a check for the missing
host route in __ipv6_ifa_notify. The only way this should happen is due
to the previously mentioned race. The host route is created when the
address is added to an interface; it is only removed on a down event
where the address is kept. Add a warning if the host route is missing
AND the device is up; this is a situation that should never happen.

Fixes: f1705ec197 ("net: ipv6: Make address flushing on ifdown optional")
Reported-by: Rajendra Dendukuri <rajendra.dendukuri@broadcom.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-04 18:08:58 -07:00
David Ahern 8ae72cbf62 Revert "ipv6: Handle race in addrconf_dad_work"
This reverts commit a3ce2a21bb.

Eric reported tests failings with commit. After digging into it,
the bottom line is that the DAD sequence is not to be messed with.
There are too many cases that are expected to proceed regardless
of whether a device is up.

Revert the patch and I will send a different solution for the
problem Rajendra reported.

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-04 14:31:10 -07:00
Jiri Pirko b7a595577e net: fib_notifier: propagate extack down to the notifier block callback
Since errors are propagated all the way up to the caller, propagate
possible extack of the caller all the way down to the notifier block
callback.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-04 11:10:56 -07:00
Jiri Pirko 55c894f762 net: fib_notifier: propagate possible error during fib notifier registration
Unlike events for registered notifier, during the registration, the
errors that happened for the block being registered are not propagated
up to the caller. Make sure the error is propagated for FIB rules and
entries.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-04 11:10:56 -07:00
Jiri Pirko 7c550daffe net: fib_notifier: make FIB notifier per-netns
Currently all users of FIB notifier only cares about events in init_net.
Later in this patchset, users get interested in other namespaces too.
However, for every registered block user is interested only about one
namespace. Make the FIB notifier registration per-netns and avoid
unnecessary calls of notifier block for other namespaces.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-04 11:10:55 -07:00
Josh Hunt 4094871db1 udp: only do GSO if # of segs > 1
Prior to this change an application sending <= 1MSS worth of data and
enabling UDP GSO would fail if the system had SW GSO enabled, but the
same send would succeed if HW GSO offload is enabled. In addition to this
inconsistency the error in the SW GSO case does not get back to the
application if sending out of a real device so the user is unaware of this
failure.

With this change we only perform GSO if the # of segments is > 1 even
if the application has enabled segmentation. I've also updated the
relevant udpgso selftests.

Fixes: bec1f6f697 ("udp: generate gso with UDP_SEGMENT")
Signed-off-by: Josh Hunt <johunt@akamai.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-03 11:47:10 -04:00
Josh Hunt 44b321e502 udp: fix gso_segs calculations
Commit dfec0ee22c ("udp: Record gso_segs when supporting UDP segmentation offload")
added gso_segs calculation, but incorrectly got sizeof() the pointer and
not the underlying data type. In addition let's fix the v6 case.

Fixes: bec1f6f697 ("udp: generate gso with UDP_SEGMENT")
Fixes: dfec0ee22c ("udp: Record gso_segs when supporting UDP segmentation offload")
Signed-off-by: Josh Hunt <johunt@akamai.com>
Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-03 11:47:10 -04:00
Eric Dumazet 6af1799aaf ipv6: drop incoming packets having a v4mapped source address
This began with a syzbot report. syzkaller was injecting
IPv6 TCP SYN packets having a v4mapped source address.

After an unsuccessful 4-tuple lookup, TCP creates a request
socket (SYN_RECV) and calls reqsk_queue_hash_req()

reqsk_queue_hash_req() calls sk_ehashfn(sk)

At this point we have AF_INET6 sockets, and the heuristic
used by sk_ehashfn() to either hash the IPv4 or IPv6 addresses
is to use ipv6_addr_v4mapped(&sk->sk_v6_daddr)

For the particular spoofed packet, we end up hashing V4 addresses
which were not initialized by the TCP IPv6 stack, so KMSAN fired
a warning.

I first fixed sk_ehashfn() to test both source and destination addresses,
but then faced various problems, including user-space programs
like packetdrill that had similar assumptions.

Instead of trying to fix the whole ecosystem, it is better
to admit that we have a dual stack behavior, and that we
can not build linux kernels without V4 stack anyway.

The dual stack API automatically forces the traffic to be IPv4
if v4mapped addresses are used at bind() or connect(), so it makes
no sense to allow IPv6 traffic to use the same v4mapped class.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-03 11:40:21 -04:00
David S. Miller 4fbb97bac1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) Remove the skb_ext_del from nf_reset, and renames it to a more
   fitting nf_reset_ct(). Patch from Florian Westphal.

2) Fix deadlock in nft_connlimit between packet path updates and
   the garbage collector.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-02 13:23:13 -07:00
David Ahern a3ce2a21bb ipv6: Handle race in addrconf_dad_work
Rajendra reported a kernel panic when a link was taken down:

[ 6870.263084] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8
[ 6870.271856] IP: [<ffffffff8efc5764>] __ipv6_ifa_notify+0x154/0x290

<snip>

[ 6870.570501] Call Trace:
[ 6870.573238] [<ffffffff8efc58c6>] ? ipv6_ifa_notify+0x26/0x40
[ 6870.579665] [<ffffffff8efc98ec>] ? addrconf_dad_completed+0x4c/0x2c0
[ 6870.586869] [<ffffffff8efe70c6>] ? ipv6_dev_mc_inc+0x196/0x260
[ 6870.593491] [<ffffffff8efc9c6a>] ? addrconf_dad_work+0x10a/0x430
[ 6870.600305] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70
[ 6870.606732] [<ffffffff8ea93a7a>] ? process_one_work+0x18a/0x430
[ 6870.613449] [<ffffffff8ea93d6d>] ? worker_thread+0x4d/0x490
[ 6870.619778] [<ffffffff8ea93d20>] ? process_one_work+0x430/0x430
[ 6870.626495] [<ffffffff8ea99dd9>] ? kthread+0xd9/0xf0
[ 6870.632145] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70
[ 6870.638573] [<ffffffff8ea99d00>] ? kthread_park+0x60/0x60
[ 6870.644707] [<ffffffff8f01ae77>] ? ret_from_fork+0x57/0x70
[ 6870.650936] Code: 31 c0 31 d2 41 b9 20 00 08 02 b9 09 00 00 0

addrconf_dad_work is kicked to be scheduled when a device is brought
up. There is a race between addrcond_dad_work getting scheduled and
taking the rtnl lock and a process taking the link down (under rtnl).
The latter removes the host route from the inet6_addr as part of
addrconf_ifdown which is run for NETDEV_DOWN. The former attempts
to use the host route in ipv6_ifa_notify. If the down event removes
the host route due to the race to the rtnl, then the BUG listed above
occurs.

This scenario does not occur when the ipv6 address is not kept
(net.ipv6.conf.all.keep_addr_on_down = 0) as addrconf_ifdown sets the
state of the ifp to DEAD. Handle when the addresses are kept by checking
IF_READY which is reset by addrconf_ifdown.

The 'dead' flag for an inet6_addr is set only under rtnl, in
addrconf_ifdown and it means the device is getting removed (or IPv6 is
disabled). The interesting cases for changing the idev flag are
addrconf_notify (NETDEV_UP and NETDEV_CHANGE) and addrconf_ifdown
(reset the flag). The former does not have the idev lock - only rtnl;
the latter has both. Based on that the existing dead + IF_READY check
can be moved to right after the rtnl_lock in addrconf_dad_work.

Fixes: f1705ec197 ("net: ipv6: Make address flushing on ifdown optional")
Reported-by: Rajendra Dendukuri <rajendra.dendukuri@broadcom.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-01 21:43:41 -04:00
Nicolas Dichtel 0d7982ce6e ipv6: minor code reorg in inet6_fill_ifla6_attrs()
Just put related code together to ease code reading: the memcpy() is
related to the nla_reserve().

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-01 14:59:03 -07:00