linux-stable.git/net/ipv6, branch v4.19.26

netfilter: ipv6: Don't preserve original oif for loopback address

2019-02-27T09:09:03+00:00

commit 15df03c661cb362366ecfc3a21820cb934f3e4ca upstream.

Commit 508b09046c0f ("netfilter: ipv6: Preserve link scope traffic
original oif") made ip6_route_me_harder() keep the original oif for
link-local and multicast packets. However, it also affected packets
for the loopback address because it used rt6_need_strict().

REDIRECT rules in the OUTPUT chain rewrite the destination to loopback
address; thus its oif should not be preserved. This commit fixes the bug
that redirected local packets are being dropped. Actually the packet was
not exactly dropped; Instead it was sent out to the original oif rather
than lo. When a packet with daddr ::1 is sent to the router, it is
effectively dropped.

Fixes: 508b09046c0f ("netfilter: ipv6: Preserve link scope traffic original oif")
Signed-off-by: Eli Cooper 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach()

2019-02-27T09:08:59+00:00

[ Upstream commit 173656accaf583698bac3f9e269884ba60d51ef4 ]

If we disabled IPv6 from the kernel command line (ipv6.disable=1), we should
not call ip6_err_gen_icmpv6_unreach(). This:

  ip link add sit1 type sit local 192.0.2.1 remote 192.0.2.2 ttl 1
  ip link set sit1 up
  ip addr add 198.51.100.1/24 dev sit1
  ping 198.51.100.2

if IPv6 is disabled at boot time, will crash the kernel.

v2: there's no need to use in6_dev_get(), use __in6_dev_get() instead,
    as we only need to check that idev exists and we are under
    rcu_read_lock() (from netif_receive_skb_internal()).

Reported-by: Jianlin Shi 
Fixes: ca15a078bd90 ("sit: generate icmpv6 error when receiving icmpv4 error")
Cc: Oussama Ghorbel 
Signed-off-by: Hangbin Liu 
Reviewed-by: Stefano Brivio 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: propagate genlmsg_reply return code

2019-02-27T09:08:58+00:00

[ Upstream commit d1f20798a119be71746949ba9b2e2ff330fdc038 ]

genlmsg_reply can fail, so propagate its return code

Fixes: 915d7e5e593 ("ipv6: sr: add code base for control plane support of SR-IPv6")
Signed-off-by: Li RongQing 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bpf: Fix [::] -> [::1] rewrite in sys_sendmsg

2019-02-27T09:08:52+00:00

[ Upstream commit e8e36984080b55ac5e57bdb09a5b570f2fc8e963 ]

sys_sendmsg has supported unspecified destination IPv6 (wildcard) for
unconnected UDP sockets since 876c7f41. When [::] is passed by user as
destination, sys_sendmsg rewrites it with [::1] to be consistent with
BSD (see "BSD'ism" comment in the code).

This didn't work when cgroup-bpf was enabled though since the rewrite
[::] -> [::1] happened before passing control to cgroup-bpf block where
fl6.daddr was updated with passed by user sockaddr_in6.sin6_addr (that
might or might not be changed by BPF program). That way if user passed
[::] as dst IPv6 it was first rewritten with [::1] by original code from
876c7f41, but then rewritten back with [::] by cgroup-bpf block.

It happened even when BPF_CGROUP_UDP6_SENDMSG program was not present
(CONFIG_CGROUP_BPF=y was enough).

The fix is to apply BSD'ism after cgroup-bpf block so that [::] is
replaced with [::1] no matter where it came from: passed by user to
sys_sendmsg or set by BPF_CGROUP_UDP6_SENDMSG program.

Fixes: 1cedee13d25a ("bpf: Hooks for sys_sendmsg")
Reported-by: Nitin Rawat 
Signed-off-by: Andrey Ignatov 
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

net: ip6_gre: initialize erspan_ver just for erspan tunnels

2019-02-23T08:07:24+00:00

[ Upstream commit 4974d5f678abb34401558559d47e2ea3d1c15cba ]

After commit c706863bc890 ("net: ip6_gre: always reports o_key to
userspace"), ip6gre and ip6gretap tunnels started reporting TUNNEL_KEY
output flag even if it is not configured.
ip6gre_fill_info checks erspan_ver value to add TUNNEL_KEY for
erspan tunnels, however in commit 84581bdae9587 ("erspan: set
erspan_ver to 1 by default when adding an erspan dev")
erspan_ver is initialized to 1 even for ip6gre or ip6gretap
Fix the issue moving erspan_ver initialization in a dedicated routine

Fixes: c706863bc890 ("net: ip6_gre: always reports o_key to userspace")
Signed-off-by: Lorenzo Bianconi 
Reviewed-by: Greg Rose 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net: fix IPv6 prefix route residue

2019-02-23T08:07:24+00:00

[ Upstream commit e75913c93f7cd5f338ab373c34c93a655bd309cb ]

Follow those steps:
 # ip addr add 2001:123::1/32 dev eth0
 # ip addr add 2001:123:456::2/64 dev eth0
 # ip addr del 2001:123::1/32 dev eth0
 # ip addr del 2001:123:456::2/64 dev eth0
and then prefix route of 2001:123::1/32 will still exist.

This is because ipv6_prefix_equal in check_cleanup_prefix_route
func does not check whether two IPv6 addresses have the same
prefix length. If the prefix of one address starts with another
shorter address prefix, even though their prefix lengths are
different, the return value of ipv6_prefix_equal is true.

Here I add a check of whether two addresses have the same prefix
to decide whether their prefixes are equal.

Fixes: 5b84efecb7d9 ("ipv6 addrconf: don't cleanup prefix route for IFA_F_NOPREFIXROUTE")
Signed-off-by: Zhiqiang Liu 
Reported-by: Wenhao Zhang 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

xfrm6_tunnel: Fix spi check in __xfrm6_tunnel_alloc_spi

2019-02-12T18:47:13+00:00

[ Upstream commit fa89a4593b927b3f59c3b69379f31d3b22272e4e ]

gcc warn this:

net/ipv6/xfrm6_tunnel.c:143 __xfrm6_tunnel_alloc_spi() warn:
 always true condition '(spi <= 4294967295) => (0-u32max <= u32max)'

'spi' is u32, which always not greater than XFRM6_TUNNEL_SPI_MAX
because of wrap around. So the second forloop will never reach.

Signed-off-by: YueHaibing 
Signed-off-by: Steffen Klassert 
Signed-off-by: Sasha Levin

ip6mr: Fix notifiers call on mroute_clean_tables()

2019-02-06T16:30:09+00:00

[ Upstream commit 146820cc240f4389cf33481c058d9493aef95e25 ]

When the MC route socket is closed, mroute_clean_tables() is called to
cleanup existing routes. Mistakenly notifiers call was put on the cleanup
of the unresolved MC route entries cache.
In a case where the MC socket closes before an unresolved route expires,
the notifier call leads to a crash, caused by the driver trying to
increment a non initialized refcount_t object [1] and then when handling
is done, to decrement it [2]. This was detected by a test recently added in
commit 6d4efada3b82 ("selftests: forwarding: Add multicast routing test").

Fix that by putting notifiers call on the resolved entries traversal,
instead of on the unresolved entries traversal.

[1]

[  245.748967] refcount_t: increment on 0; use-after-free.
[  245.754829] WARNING: CPU: 3 PID: 3223 at lib/refcount.c:153 refcount_inc_checked+0x2b/0x30
...
[  245.802357] Hardware name: Mellanox Technologies Ltd. MSN2740/SA001237, BIOS 5.6.5 06/07/2016
[  245.811873] RIP: 0010:refcount_inc_checked+0x2b/0x30
...
[  245.907487] Call Trace:
[  245.910231]  mlxsw_sp_router_fib_event.cold.181+0x42/0x47 [mlxsw_spectrum]
[  245.917913]  notifier_call_chain+0x45/0x7
[  245.922484]  atomic_notifier_call_chain+0x15/0x20
[  245.927729]  call_fib_notifiers+0x15/0x30
[  245.932205]  mroute_clean_tables+0x372/0x3f
[  245.936971]  ip6mr_sk_done+0xb1/0xc0
[  245.940960]  ip6_mroute_setsockopt+0x1da/0x5f0
...

[2]

[  246.128487] refcount_t: underflow; use-after-free.
[  246.133859] WARNING: CPU: 0 PID: 7 at lib/refcount.c:187 refcount_sub_and_test_checked+0x4c/0x60
[  246.183521] Hardware name: Mellanox Technologies Ltd. MSN2740/SA001237, BIOS 5.6.5 06/07/2016
...
[  246.193062] Workqueue: mlxsw_core_ordered mlxsw_sp_router_fibmr_event_work [mlxsw_spectrum]
[  246.202394] RIP: 0010:refcount_sub_and_test_checked+0x4c/0x60
...
[  246.298889] Call Trace:
[  246.301617]  refcount_dec_and_test_checked+0x11/0x20
[  246.307170]  mlxsw_sp_router_fibmr_event_work.cold.196+0x47/0x78 [mlxsw_spectrum]
[  246.315531]  process_one_work+0x1fa/0x3f0
[  246.320005]  worker_thread+0x2f/0x3e0
[  246.324083]  kthread+0x118/0x130
[  246.327683]  ? wq_update_unbound_numa+0x1b0/0x1b0
[  246.332926]  ? kthread_park+0x80/0x80
[  246.337013]  ret_from_fork+0x1f/0x30

Fixes: 088aa3eec2ce ("ip6mr: Support fib notifications")
Signed-off-by: Nir Dotan 
Reviewed-by: Ido Schimmel 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: ip6_gre: always reports o_key to userspace

2019-02-06T16:30:08+00:00

[ Upstream commit c706863bc8902d0c2d1a5a27ac8e1ead5d06b79d ]

As Erspan_v4, Erspan_v6 protocol relies on o_key to configure
session id header field. However TUNNEL_KEY bit is cleared in
ip6erspan_tunnel_xmit since ERSPAN protocol does not set the key field
of the external GRE header and so the configured o_key is not reported
to userspace. The issue can be triggered with the following reproducer:

$ip link add ip6erspan1 type ip6erspan local 2000::1 remote 2000::2 \
    key 1 seq erspan_ver 1
$ip link set ip6erspan1 up
ip -d link sh ip6erspan1

ip6erspan1@NONE:  mtu 1422 qdisc noop state DOWN mode DEFAULT
    link/ether ba:ff:09:24:c3:0e brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 1500
    ip6erspan remote 2000::2 local 2000::1 encaplimit 4 flowlabel 0x00000 ikey 0.0.0.1 iseq oseq

Fix the issue adding TUNNEL_KEY bit to the o_flags parameter in
ip6gre_fill_info

Fixes: 5a963eb61b7c ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Lorenzo Bianconi 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: ip_gre: use erspan key field for tunnel lookup

2019-02-06T16:30:06+00:00

[ Upstream commit cb73ee40b1b381eaf3749e6dbeed567bb38e5258 ]

Use ERSPAN key header field as tunnel key in gre_parse_header routine
since ERSPAN protocol sets the key field of the external GRE header to
0 resulting in a tunnel lookup fail in ip6gre_err.
In addition remove key field parsing and pskb_may_pull check in
erspan_rcv and ip6erspan_rcv

Fixes: 5a963eb61b7c ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Lorenzo Bianconi 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman