Commit Graph

294 Commits

Author SHA1 Message Date
Eric Dumazet
cb34b7cf17 ipv6/sit: use DEV_STATS_INC() to avoid data-races
syzbot/KCSAN reported that multiple cpus are updating dev->stats.tx_error
concurrently.

This is because sit tunnels are NETIF_F_LLTX, meaning their ndo_start_xmit()
is not protected by a spinlock.

While original KCSAN report was about tx path, rx path has the same issue.

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-16 12:48:44 +00:00
Eric Dumazet
d89d7ff012 ipv6: ensure sane device mtu in tunnels
Another syzbot report [1] with no reproducer hints
at a bug in ip6_gre tunnel (dev:ip6gretap0)

Since ipv6 mcast code makes sure to read dev->mtu once
and applies a sanity check on it (see commit b9b312a7a4
"ipv6: mcast: better catch silly mtu values"), a remaining
possibility is that a layer is able to set dev->mtu to
an underflowed value (high order bit set).

This could happen indeed in ip6gre_tnl_link_config_route(),
ip6_tnl_link_config() and ipip6_tunnel_bind_dev()

Make sure to sanitize mtu value in a local variable before
it is written once on dev->mtu, as lockless readers could
catch wrong temporary value.

[1]
skbuff: skb_over_panic: text:ffff80000b7a2f38 len:40 put:40 head:ffff000149dcf200 data:ffff000149dcf2b0 tail:0xd8 end:0xc0 dev:ip6gretap0
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:120
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 10241 Comm: kworker/1:1 Not tainted 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022
Workqueue: mld mld_ifc_work
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : skb_panic+0x4c/0x50 net/core/skbuff.c:116
lr : skb_panic+0x4c/0x50 net/core/skbuff.c:116
sp : ffff800020dd3b60
x29: ffff800020dd3b70 x28: 0000000000000000 x27: ffff00010df2a800
x26: 00000000000000c0 x25: 00000000000000b0 x24: ffff000149dcf200
x23: 00000000000000c0 x22: 00000000000000d8 x21: ffff80000b7a2f38
x20: ffff00014c2f7800 x19: 0000000000000028 x18: 00000000000001a9
x17: 0000000000000000 x16: ffff80000db49158 x15: ffff000113bf1a80
x14: 0000000000000000 x13: 00000000ffffffff x12: ffff000113bf1a80
x11: ff808000081c0d5c x10: 0000000000000000 x9 : 73f125dc5c63ba00
x8 : 73f125dc5c63ba00 x7 : ffff800008161d1c x6 : 0000000000000000
x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000
x2 : ffff0001fefddcd0 x1 : 0000000100000000 x0 : 0000000000000089
Call trace:
skb_panic+0x4c/0x50 net/core/skbuff.c:116
skb_over_panic net/core/skbuff.c:125 [inline]
skb_put+0xd4/0xdc net/core/skbuff.c:2049
ip6_mc_hdr net/ipv6/mcast.c:1714 [inline]
mld_newpack+0x14c/0x270 net/ipv6/mcast.c:1765
add_grhead net/ipv6/mcast.c:1851 [inline]
add_grec+0xa20/0xae0 net/ipv6/mcast.c:1989
mld_send_cr+0x438/0x5a8 net/ipv6/mcast.c:2115
mld_ifc_work+0x38/0x290 net/ipv6/mcast.c:2653
process_one_work+0x2d8/0x504 kernel/workqueue.c:2289
worker_thread+0x340/0x610 kernel/workqueue.c:2436
kthread+0x12c/0x158 kernel/kthread.c:376
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860
Code: 91011400 aa0803e1 a90027ea 94373093 (d4210000)

Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20221024020124.3756833-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-25 16:04:22 -07:00
Liu Jian
b86fca800a net: Add helper function to parse netlink msg of ip_tunnel_parm
Add ip_tunnel_netlink_parms to parse netlink msg of ip_tunnel_parm.
Reduces duplicate code, no actual functional changes.

Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-10-03 07:59:06 +01:00
Liu Jian
537dd2d9fb net: Add helper function to parse netlink msg of ip_tunnel_encap
Add ip_tunnel_netlink_encap_parms to parse netlink msg of ip_tunnel_encap.
Reduces duplicate code, no actual functional changes.

Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-10-03 07:59:06 +01:00
Wolfram Sang
7574cc5837 ipv6: move from strlcpy with unused retval to strscpy
Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20220818210220.8491-1-wsa+renesas@sang-engineering.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-22 17:59:42 -07:00
Jakub Kicinski
0d8730f07c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.c
  9c5de246c1 ("net: sparx5: mdb add/del handle non-sparx5 devices")
  fbb89d02e3 ("net: sparx5: Allow mdb entries to both CPU and ports")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-30 16:31:00 -07:00
katrinzhou
adabdd8f6a ipv6/sit: fix ipip6_tunnel_get_prl return value
When kcalloc fails, ipip6_tunnel_get_prl() should return -ENOMEM.
Move the position of label "out" to return correctly.

Addresses-Coverity: ("Unused value")
Fixes: 300aaeeaab ("[IPV6] SIT: Add SIOCGETPRL ioctl to get/dump PRL.")
Signed-off-by: katrinzhou <katrinzhou@tencent.com>
Reviewed-by: Eric Dumazet<edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220628035030.1039171-1-zys.zljxml@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-28 21:00:34 -07:00
Eric Dumazet
3a960ca7f6 sit: use dev_sw_netstats_rx_add()
We have a convenient helper, let's use it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-09 21:53:10 -07:00
Jakub Kicinski
d62607c3fe net: rename reference+tracking helpers
Netdev reference helpers have a dev_ prefix for historic
reasons. Renaming the old helpers would be too much churn
but we can rename the tracking ones which are relatively
recent and should be the default for new code.

Rename:
 dev_hold_track()    -> netdev_hold()
 dev_put_track()     -> netdev_put()
 dev_replace_track() -> netdev_ref_replace()

Link: https://lore.kernel.org/r/20220608043955.919359-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-09 21:52:55 -07:00
Ignat Korchagin
ed6ae5ca43 sit: allow encapsulated IPv6 traffic to be delivered locally
While experimenting with FOU encapsulation Amir noticed that encapsulated IPv6
traffic fails to be delivered, if the peer IP address is configured locally.

It can be easily verified by creating a sit interface like below:

$ sudo ip link add name fou_test type sit remote 127.0.0.1 encap fou encap-sport auto encap-dport 1111
$ sudo ip link set fou_test up

and sending some IPv4 and IPv6 traffic to it

$ ping -I fou_test -c 1 1.1.1.1
$ ping6 -I fou_test -c 1 fe80::d0b0:dfff:fe4c:fcbc

"tcpdump -i any udp dst port 1111" will confirm that only the first IPv4 ping
was encapsulated and attempted to be delivered.

This seems like a limitation: for example, in a cloud environment the "peer"
service may be arbitrarily scheduled on any server within the cluster, where all
nodes are trying to send encapsulated traffic. And the unlucky node will not be
able to. Moreover, delivering encapsulated IPv4 traffic locally is allowed.

But I may not have all the context about this restriction and this code predates
the observable git history.

Reported-by: Amir Razmjou <arazmjou@cloudflare.com>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220107123842.211335-1-ignat@cloudflare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-12 13:56:07 -08:00
Jakub Kicinski
7cd2802d74 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-16 16:13:19 -08:00
Eric Dumazet
e28587cc49 sit: do not call ipip6_dev_free() from sit_init_net()
ipip6_dev_free is sit dev->priv_destructor, already called
by register_netdevice() if something goes wrong.

Alternative would be to make ipip6_dev_free() robust against
multiple invocations, but other drivers do not implement this
strategy.

syzbot reported:

dst_release underflow
WARNING: CPU: 0 PID: 5059 at net/core/dst.c:173 dst_release+0xd8/0xe0 net/core/dst.c:173
Modules linked in:
CPU: 1 PID: 5059 Comm: syz-executor.4 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:dst_release+0xd8/0xe0 net/core/dst.c:173
Code: 4c 89 f2 89 d9 31 c0 5b 41 5e 5d e9 da d5 44 f9 e8 1d 90 5f f9 c6 05 87 48 c6 05 01 48 c7 c7 80 44 99 8b 31 c0 e8 e8 67 29 f9 <0f> 0b eb 85 0f 1f 40 00 53 48 89 fb e8 f7 8f 5f f9 48 83 c3 a8 48
RSP: 0018:ffffc9000aa5faa0 EFLAGS: 00010246
RAX: d6894a925dd15a00 RBX: 00000000ffffffff RCX: 0000000000040000
RDX: ffffc90005e19000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: 0000000000000000 R08: ffffffff816a1f42 R09: ffffed1017344f2c
R10: ffffed1017344f2c R11: 0000000000000000 R12: 0000607f462b1358
R13: 1ffffffff1bfd305 R14: ffffe8ffffcb1358 R15: dffffc0000000000
FS:  00007f66c71a2700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f88aaed5058 CR3: 0000000023e0f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 dst_cache_destroy+0x107/0x1e0 net/core/dst_cache.c:160
 ipip6_dev_free net/ipv6/sit.c:1414 [inline]
 sit_init_net+0x229/0x550 net/ipv6/sit.c:1936
 ops_init+0x313/0x430 net/core/net_namespace.c:140
 setup_net+0x35b/0x9d0 net/core/net_namespace.c:326
 copy_net_ns+0x359/0x5c0 net/core/net_namespace.c:470
 create_new_namespaces+0x4ce/0xa00 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x11e/0x180 kernel/nsproxy.c:226
 ksys_unshare+0x57d/0xb50 kernel/fork.c:3075
 __do_sys_unshare kernel/fork.c:3146 [inline]
 __se_sys_unshare kernel/fork.c:3144 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3144
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f66c882ce99
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f66c71a2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f66c893ff60 RCX: 00007f66c882ce99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000048040200
RBP: 00007f66c8886ff1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff6634832f R14: 00007f66c71a2300 R15: 0000000000022000
 </TASK>

Fixes: cf124db566 ("net: Fix inconsistent teardown and release of private netdev state.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20211216111741.1387540-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-16 08:38:10 -08:00
Eric Dumazet
c0fd407a06 sit: add net device refcount tracking to ip_tunnel
Note that other ip_tunnel users do not seem to hold a reference
on tunnel->dev. Probably needs some investigations.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-06 16:05:11 -08:00
Jakub Kicinski
5a1b7e1a53 ip: use dev_addr_set() in tunnels
Use dev_addr_set() instead of writing to netdev->dev_addr
directly in ip tunnels drivers.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-13 09:41:37 -07:00
Arnd Bergmann
3e7a1c7c56 ip_tunnel: use ndo_siocdevprivate
The various ipv4 and ipv6 tunnel drivers each implement a set
of 12 SIOCDEVPRIVATE commands for managing tunnels. These
all work correctly in compat mode.

Move them over to the new .ndo_siocdevprivate operation.

Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David Ahern <dsahern@kernel.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-27 20:11:44 +01:00
Vasily Averin
1b51d82719 memcg: ipv6/sit: account and don't WARN on ip_tunnel_prl structs allocation
Author: Andrey Ryabinin <aryabinin@virtuozzo.com>

The size of the ip_tunnel_prl structs allocation is controllable from
user-space, thus it's better to avoid spam in dmesg if allocation failed.
Also add __GFP_ACCOUNT as this is a good candidate for per-memcg
accounting. Allocation is temporary and limited by 4GB.

Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 06:00:38 -07:00
Guillaume Nault
730eed2772 sit: allow redirecting ip6ip, ipip and mplsip packets to eth devices
Even though sit transports L3 data (IPv6, IPv4 or MPLS) packets, it
needs to reset the mac_header pointer, so that other parts of the stack
don't mistakenly access the outer header after the packet has been
decapsulated. There are two rx handlers to modify: ipip6_rcv() for the
ip6ip mode and sit_tunnel_rcv() which is used to re-implement the ipip
and mplsip modes of ipip.ko.

This allows to push an Ethernet header to sit packets and redirect
them to an Ethernet device:

  $ tc filter add dev sit0 ingress matchall          \
      action vlan push_eth dst_mac 00:00:5e:00:53:01 \
                           src_mac 00:00:5e:00:53:00 \
      action mirred egress redirect dev eth0

Without this patch, push_eth refuses to add an ethernet header because
the skb appears to already have a MAC header.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-28 12:44:17 -07:00
David S. Miller
126285651b Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net
Bug fixes overlapping feature additions and refactoring, mostly.

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 13:01:52 -07:00
zhang kai
261ba78cc3 sit: set name of device back to struct parms
addrconf_set_sit_dstaddr will use parms->name.

Signed-off-by: zhang kai <zhangkaiheb@126.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-03 13:57:36 -07:00
zhang kai
7f0e869c4e sit: replace 68 with micro IPV4_MIN_MTU
Use meaningfull micro IPV4_MIN_MTU

Signed-off-by: zhang kai <zhangkaiheb@126.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-02 13:28:05 -07:00
Jakub Kicinski
8203c7ce4e Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
 - keep the ZC code, drop the code related to reinit
net/bridge/netfilter/ebtables.c
 - fix build after move to net_generic

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-04-17 11:08:07 -07:00
Hristo Venev
610f8c0fc8 net: sit: Unregister catch-all devices
A sit interface created without a local or a remote address is linked
into the `sit_net::tunnels_wc` list of its original namespace. When
deleting a network namespace, delete the devices that have been moved.

The following script triggers a null pointer dereference if devices
linked in a deleted `sit_net` remain:

    for i in `seq 1 30`; do
        ip netns add ns-test
        ip netns exec ns-test ip link add dev veth0 type veth peer veth1
        ip netns exec ns-test ip link add dev sit$i type sit dev veth0
        ip netns exec ns-test ip link set dev sit$i netns $$
        ip netns del ns-test
    done
    for i in `seq 1 30`; do
        ip link del dev sit$i
    done

Fixes: 5e6700b3bf ("sit: add support of x-netns")
Signed-off-by: Hristo Venev <hristo@venev.name>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-13 14:31:52 -07:00
Eric Dumazet
0d7a7b2014 ipv6: remove extra dev_hold() for fallback tunnels
My previous commits added a dev_hold() in tunnels ndo_init(),
but forgot to remove it from special functions setting up fallback tunnels.

Fallback tunnels do call their respective ndo_init()

This leads to various reports like :

unregister_netdevice: waiting for ip6gre0 to become free. Usage count = 2

Fixes: 48bb569726 ("ip6_tunnel: sit: proper dev_{hold|put} in ndo_[un]init methods")
Fixes: 6289a98f08 ("sit: proper dev_{hold|put} in ndo_[un]init methods")
Fixes: 40cb881b5a ("ip6_vti: proper dev_{hold|put} in ndo_[un]init methods")
Fixes: 7f700334be ("ip6_gre: proper dev_{hold|put} in ndo_[un]init methods")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-31 14:53:11 -07:00
Eric Dumazet
6289a98f08 sit: proper dev_{hold|put} in ndo_[un]init methods
After adopting CONFIG_PCPU_DEV_REFCNT=n option, syzbot was able to trigger
a warning [1]

Issue here is that:

- all dev_put() should be paired with a corresponding prior dev_hold().

- A driver doing a dev_put() in its ndo_uninit() MUST also
  do a dev_hold() in its ndo_init(), only when ndo_init()
  is returning 0.

Otherwise, register_netdevice() would call ndo_uninit()
in its error path and release a refcount too soon.

Fixes: 919067cc84 ("net: add CONFIG_PCPU_DEV_REFCNT")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-29 16:31:51 -07:00
kernel test robot
284fda1eff sit: use min
Opportunity for min()

Generated by: scripts/coccinelle/misc/minmax.cocci

CC: Denis Efremov <efremov@linux.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: kernel test robot <lkp@intel.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-28 17:58:39 -07:00
Jason A. Donenfeld
4372339efc net: always use icmp{,v6}_ndo_send from ndo_start_xmit
There were a few remaining tunnel drivers that didn't receive the prior
conversion to icmp{,v6}_ndo_send. Knowing now that this could lead to
memory corrution (see ee576c47db ("net: icmp: pass zeroed opts from
icmp{,v6}_ndo_send before sending") for details), there's even more
imperative to have these all converted. So this commit goes through the
remaining cases that I could find and does a boring translation to the
ndo variety.

The Fixes: line below is the merge that originally added icmp{,v6}_
ndo_send and converted the first batch of icmp{,v6}_send users. The
rationale then for the change applies equally to this patch. It's just
that these drivers were left out of the initial conversion because these
network devices are hiding in net/ rather than in drivers/net/.

Cc: Florian Westphal <fw@strlen.de>
Cc: Willem de Bruijn <willemb@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David Ahern <dsahern@kernel.org>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Fixes: 803381f9f1 ("Merge branch 'icmp-account-for-NAT-when-sending-icmps-from-ndo-layer'")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-01 13:11:35 -08:00
Jakub Kicinski
47e4bb147a net: sit: unregister_netdevice on newlink's error path
We need to unregister the netdevice if config failed.
.ndo_uninit takes care of most of the heavy lifting.

This was uncovered by recent commit c269a24ce0 ("net: make
free_netdev() more lenient with unregistering devices").
Previously the partially-initialized device would be left
in the system.

Reported-and-tested-by: syzbot+2393580080a2da190f04@syzkaller.appspotmail.com
Fixes: e2f1f072db ("sit: allow to configure 6rd tunnels via netlink")
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Link: https://lore.kernel.org/r/20210114012947.2515313-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-14 10:26:46 -08:00
Jakub Kicinski
e1d9d7b913 Merge https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-12 16:54:48 -08:00
Heiner Kallweit
98d7fc4638 ipv4/ipv6: switch to dev_get_tstats64
Replace ip_tunnel_get_stats64() with the new identical core function
dev_get_tstats64().

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-09 17:50:28 -08:00
Oliver Herms
8ef9ba4d66 IPv6: Set SIT tunnel hard_header_len to zero
Due to the legacy usage of hard_header_len for SIT tunnels while
already using infrastructure from net/ipv4/ip_tunnel.c the
calculation of the path MTU in tnl_update_pmtu is incorrect.
This leads to unnecessary creation of MTU exceptions for any
flow going over a SIT tunnel.

As SIT tunnels do not have a header themsevles other than their
transport (L3, L2) headers we're leaving hard_header_len set to zero
as tnl_update_pmtu is already taking care of the transport headers
sizes.

This will also help avoiding unnecessary IPv6 GC runs and spinlock
contention seen when using SIT tunnels and for more than
net.ipv6.route.gc_thresh flows.

Fixes: c544193214 ("GRE: Refactor GRE tunneling code.")
Signed-off-by: Oliver Herms <oliver.peter.herms@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20201103104133.GA1573211@tws
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-09 15:07:40 -08:00
Jason A. Donenfeld
75ea1f4773 net: sit: implement header_ops->parse_protocol for AF_PACKET
Sit uses skb->protocol to determine packet type, and bails out if it's
not set. For AF_PACKET injection, we need to support its call chain of:

    packet_sendmsg -> packet_snd -> packet_parse_headers ->
      dev_parse_header_protocol -> parse_protocol

Without a valid parse_protocol, this returns zero, and sit rejects the
skb. So, this wires up the ip_tunnel handler for layer 3 packets for
that case.

Reported-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-30 12:29:39 -07:00
Christoph Hellwig
f60fe2df93 sit: impement ->ndo_tunnel_ctl
Implement the ->ndo_tunnel_ctl method, and use ip_tunnel_ioctl to
handle userspace requests for the SIOCGETTUNNEL, SIOCADDTUNNEL,
SIOCCHGTUNNEL and SIOCDELTUNNEL ioctls.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-19 15:45:12 -07:00
Christoph Hellwig
fd5d687b76 sit: refactor ipip6_tunnel_ioctl
Split the ioctl handler into one function per command instead of having
a all the logic sit in one giant switch statement.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-19 15:45:12 -07:00
Hangbin Liu
4d42df46d6 sit: do not confirm neighbor when do pmtu update
When do IPv6 tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end,
we should not call dst_confirm_neigh() as there is no two-way communication.

v5: No change.
v4: No change.
v3: Do not remove dst_confirm_neigh, but add a new bool parameter in
    dst_ops.update_pmtu to control whether we should do neighbor confirm.
    Also split the big patch to small ones for each area.
v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu.

Reviewed-by: Guillaume Nault <gnault@redhat.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-24 22:28:55 -08:00
Haishuang Yan
6e3d1bbbba sit: use dst_cache in ipip6_tunnel_xmit
Same as other ip tunnel, use dst_cache in xmit action to avoid
unnecessary fib lookups.

Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-14 12:15:28 -07:00
Thomas Gleixner
2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Stephen Suryaputra
ff6ab32bd4 vrf: sit mtu should not be updated when vrf netdev is the link
VRF netdev mtu isn't typically set and have an mtu of 65536. When the
link of a tunnel is set, the tunnel mtu is changed from 1480 to the link
mtu minus tunnel header. In the case of VRF netdev is the link, then the
tunnel mtu becomes 65516. So, fix it by not setting the tunnel mtu in
this case.

Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-07 12:19:19 -07:00
Lorenzo Bianconi
bb9bd814eb ipv6: sit: reset ip header pointer in ipip6_rcv
ipip6 tunnels run iptunnel_pull_header on received skbs. This can
determine the following use-after-free accessing iph pointer since
the packet will be 'uncloned' running pskb_expand_head if it is a
cloned gso skb (e.g if the packet has been sent though a veth device)

[  706.369655] BUG: KASAN: use-after-free in ipip6_rcv+0x1678/0x16e0 [sit]
[  706.449056] Read of size 1 at addr ffffe01b6bd855f5 by task ksoftirqd/1/=
[  706.669494] Hardware name: HPE ProLiant m400 Server/ProLiant m400 Server, BIOS U02 08/19/2016
[  706.771839] Call trace:
[  706.801159]  dump_backtrace+0x0/0x2f8
[  706.845079]  show_stack+0x24/0x30
[  706.884833]  dump_stack+0xe0/0x11c
[  706.925629]  print_address_description+0x68/0x260
[  706.982070]  kasan_report+0x178/0x340
[  707.025995]  __asan_report_load1_noabort+0x30/0x40
[  707.083481]  ipip6_rcv+0x1678/0x16e0 [sit]
[  707.132623]  tunnel64_rcv+0xd4/0x200 [tunnel4]
[  707.185940]  ip_local_deliver_finish+0x3b8/0x988
[  707.241338]  ip_local_deliver+0x144/0x470
[  707.289436]  ip_rcv_finish+0x43c/0x14b0
[  707.335447]  ip_rcv+0x628/0x1138
[  707.374151]  __netif_receive_skb_core+0x1670/0x2600
[  707.432680]  __netif_receive_skb+0x28/0x190
[  707.482859]  process_backlog+0x1d0/0x610
[  707.529913]  net_rx_action+0x37c/0xf68
[  707.574882]  __do_softirq+0x288/0x1018
[  707.619852]  run_ksoftirqd+0x70/0xa8
[  707.662734]  smpboot_thread_fn+0x3a4/0x9e8
[  707.711875]  kthread+0x2c8/0x350
[  707.750583]  ret_from_fork+0x10/0x18

[  707.811302] Allocated by task 16982:
[  707.854182]  kasan_kmalloc.part.1+0x40/0x108
[  707.905405]  kasan_kmalloc+0xb4/0xc8
[  707.948291]  kasan_slab_alloc+0x14/0x20
[  707.994309]  __kmalloc_node_track_caller+0x158/0x5e0
[  708.053902]  __kmalloc_reserve.isra.8+0x54/0xe0
[  708.108280]  __alloc_skb+0xd8/0x400
[  708.150139]  sk_stream_alloc_skb+0xa4/0x638
[  708.200346]  tcp_sendmsg_locked+0x818/0x2b90
[  708.251581]  tcp_sendmsg+0x40/0x60
[  708.292376]  inet_sendmsg+0xf0/0x520
[  708.335259]  sock_sendmsg+0xac/0xf8
[  708.377096]  sock_write_iter+0x1c0/0x2c0
[  708.424154]  new_sync_write+0x358/0x4a8
[  708.470162]  __vfs_write+0xc4/0xf8
[  708.510950]  vfs_write+0x12c/0x3d0
[  708.551739]  ksys_write+0xcc/0x178
[  708.592533]  __arm64_sys_write+0x70/0xa0
[  708.639593]  el0_svc_handler+0x13c/0x298
[  708.686646]  el0_svc+0x8/0xc

[  708.739019] Freed by task 17:
[  708.774597]  __kasan_slab_free+0x114/0x228
[  708.823736]  kasan_slab_free+0x10/0x18
[  708.868703]  kfree+0x100/0x3d8
[  708.905320]  skb_free_head+0x7c/0x98
[  708.948204]  skb_release_data+0x320/0x490
[  708.996301]  pskb_expand_head+0x60c/0x970
[  709.044399]  __iptunnel_pull_header+0x3b8/0x5d0
[  709.098770]  ipip6_rcv+0x41c/0x16e0 [sit]
[  709.146873]  tunnel64_rcv+0xd4/0x200 [tunnel4]
[  709.200195]  ip_local_deliver_finish+0x3b8/0x988
[  709.255596]  ip_local_deliver+0x144/0x470
[  709.303692]  ip_rcv_finish+0x43c/0x14b0
[  709.349705]  ip_rcv+0x628/0x1138
[  709.388413]  __netif_receive_skb_core+0x1670/0x2600
[  709.446943]  __netif_receive_skb+0x28/0x190
[  709.497120]  process_backlog+0x1d0/0x610
[  709.544169]  net_rx_action+0x37c/0xf68
[  709.589131]  __do_softirq+0x288/0x1018

[  709.651938] The buggy address belongs to the object at ffffe01b6bd85580
                which belongs to the cache kmalloc-1024 of size 1024
[  709.804356] The buggy address is located 117 bytes inside of
                1024-byte region [ffffe01b6bd85580, ffffe01b6bd85980)
[  709.946340] The buggy address belongs to the page:
[  710.003824] page:ffff7ff806daf600 count:1 mapcount:0 mapping:ffffe01c4001f600 index:0x0
[  710.099914] flags: 0xfffff8000000100(slab)
[  710.149059] raw: 0fffff8000000100 dead000000000100 dead000000000200 ffffe01c4001f600
[  710.242011] raw: 0000000000000000 0000000000380038 00000001ffffffff 0000000000000000
[  710.334966] page dumped because: kasan: bad access detected

Fix it resetting iph pointer after iptunnel_pull_header

Fixes: a09a4c8dd1 ("tunnels: Remove encapsulation offloads on decap")
Tested-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-04 18:34:23 -07:00
Miaohe Lin
a843dc4eba net: sit: fix UBSAN Undefined behaviour in check_6rd
In func check_6rd,tunnel->ip6rd.relay_prefixlen may equal to
32,so UBSAN complain about it.

UBSAN: Undefined behaviour in net/ipv6/sit.c:781:47
shift exponent 32 is too large for 32-bit type 'unsigned int'
CPU: 6 PID: 20036 Comm: syz-executor.0 Not tainted 4.19.27 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1
04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xca/0x13e lib/dump_stack.c:113
ubsan_epilogue+0xe/0x81 lib/ubsan.c:159
__ubsan_handle_shift_out_of_bounds+0x293/0x2e8 lib/ubsan.c:425
check_6rd.constprop.9+0x433/0x4e0 net/ipv6/sit.c:781
try_6rd net/ipv6/sit.c:806 [inline]
ipip6_tunnel_xmit net/ipv6/sit.c:866 [inline]
sit_tunnel_xmit+0x141c/0x2720 net/ipv6/sit.c:1033
__netdev_start_xmit include/linux/netdevice.h:4300 [inline]
netdev_start_xmit include/linux/netdevice.h:4309 [inline]
xmit_one net/core/dev.c:3243 [inline]
dev_hard_start_xmit+0x17c/0x780 net/core/dev.c:3259
__dev_queue_xmit+0x1656/0x2500 net/core/dev.c:3829
neigh_output include/net/neighbour.h:501 [inline]
ip6_finish_output2+0xa36/0x2290 net/ipv6/ip6_output.c:120
ip6_finish_output+0x3e7/0xa20 net/ipv6/ip6_output.c:154
NF_HOOK_COND include/linux/netfilter.h:278 [inline]
ip6_output+0x1e2/0x720 net/ipv6/ip6_output.c:171
dst_output include/net/dst.h:444 [inline]
ip6_local_out+0x99/0x170 net/ipv6/output_core.c:176
ip6_send_skb+0x9d/0x2f0 net/ipv6/ip6_output.c:1697
ip6_push_pending_frames+0xc0/0x100 net/ipv6/ip6_output.c:1717
rawv6_push_pending_frames net/ipv6/raw.c:616 [inline]
rawv6_sendmsg+0x2435/0x3530 net/ipv6/raw.c:946
inet_sendmsg+0xf8/0x5c0 net/ipv4/af_inet.c:798
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg+0xc8/0x110 net/socket.c:631
___sys_sendmsg+0x6cf/0x890 net/socket.c:2114
__sys_sendmsg+0xf0/0x1b0 net/socket.c:2152
do_syscall_64+0xc8/0x580 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe

Signed-off-by: linmiaohe <linmiaohe@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-11 10:32:45 -07:00
Mao Wenan
07f12b26e2 net: sit: fix memory leak in sit_init_net()
If register_netdev() is failed to register sitn->fb_tunnel_dev,
it will go to err_reg_dev and forget to free netdev(sitn->fb_tunnel_dev).

BUG: memory leak
unreferenced object 0xffff888378daad00 (size 512):
  comm "syz-executor.1", pid 4006, jiffies 4295121142 (age 16.115s)
  hex dump (first 32 bytes):
    00 e6 ed c0 83 88 ff ff 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
backtrace:
    [<00000000d6dcb63e>] kvmalloc include/linux/mm.h:577 [inline]
    [<00000000d6dcb63e>] kvzalloc include/linux/mm.h:585 [inline]
    [<00000000d6dcb63e>] netif_alloc_netdev_queues net/core/dev.c:8380 [inline]
    [<00000000d6dcb63e>] alloc_netdev_mqs+0x600/0xcc0 net/core/dev.c:8970
    [<00000000867e172f>] sit_init_net+0x295/0xa40 net/ipv6/sit.c:1848
    [<00000000871019fa>] ops_init+0xad/0x3e0 net/core/net_namespace.c:129
    [<00000000319507f6>] setup_net+0x2ba/0x690 net/core/net_namespace.c:314
    [<0000000087db4f96>] copy_net_ns+0x1dc/0x330 net/core/net_namespace.c:437
    [<0000000057efc651>] create_new_namespaces+0x382/0x730 kernel/nsproxy.c:107
    [<00000000676f83de>] copy_namespaces+0x2ed/0x3d0 kernel/nsproxy.c:165
    [<0000000030b74bac>] copy_process.part.27+0x231e/0x6db0 kernel/fork.c:1919
    [<00000000fff78746>] copy_process kernel/fork.c:1713 [inline]
    [<00000000fff78746>] _do_fork+0x1bc/0xe90 kernel/fork.c:2224
    [<000000001c2e0d1c>] do_syscall_64+0xc8/0x580 arch/x86/entry/common.c:290
    [<00000000ec48bd44>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
    [<0000000039acff8a>] 0xffffffffffffffff

Signed-off-by: Mao Wenan <maowenan@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-02 00:53:23 -08:00
Hangbin Liu
173656acca sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach()
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 <jishi@redhat.com>
Fixes: ca15a078bd ("sit: generate icmpv6 error when receiving icmpv4 error")
Cc: Oussama Ghorbel <ghorbel@pivasoftware.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-07 10:48:42 -08:00
Willem de Bruijn
cb9f1b7838 ip: validate header length on virtual device xmit
KMSAN detected read beyond end of buffer in vti and sit devices when
passing truncated packets with PF_PACKET. The issue affects additional
ip tunnel devices.

Extend commit 76c0ddd8c3 ("ip6_tunnel: be careful when accessing the
inner header") and commit ccfec9e5cb ("ip_tunnel: be careful when
accessing the inner header").

Move the check to a separate helper and call at the start of each
ndo_start_xmit function in net/ipv4 and net/ipv6.

Minor changes:
- convert dev_kfree_skb to kfree_skb on error path,
  as dev_kfree_skb calls consume_skb which is not for error paths.
- use pskb_network_may_pull even though that is pedantic here,
  as the same as pskb_may_pull for devices without llheaders.
- do not cache ipv6 hdrs if used only once
  (unsafe across pskb_may_pull, was more relevant to earlier patch)

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-01 12:05:02 -08:00
Maciej Żenczykowski
1042caa79e net-ipv4: remove 2 always zero parameters from ipv4_redirect()
(the parameters in question are mark and flow_flags)

Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 20:30:55 -07:00
Maciej Żenczykowski
d888f39666 net-ipv4: remove 2 always zero parameters from ipv4_update_pmtu()
(the parameters in question are mark and flow_flags)

Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 20:30:55 -07:00
Nicolas Dichtel
f7ff1fde94 ip6_tunnel: remove magic mtu value 0xFFF8
I don't know where this value comes from (probably a copy and paste and
paste and paste ...).
Let's use standard values which are a bit greater.

Link: https://git.kernel.org/pub/scm/linux/kernel/git/davem/netdev-vger-cvs.git/commit/?id=e5afd356a411a
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-01 13:56:30 -04:00
Eric Dumazet
b95211e066 ipv6: sit: better validate user provided tunnel names
Use dev_valid_name() to make sure user does not provide illegal
device name.

syzbot caught the following bug :

BUG: KASAN: stack-out-of-bounds in strlcpy include/linux/string.h:300 [inline]
BUG: KASAN: stack-out-of-bounds in ipip6_tunnel_locate+0x63b/0xaa0 net/ipv6/sit.c:254
Write of size 33 at addr ffff8801b64076d8 by task syzkaller932654/4453

CPU: 0 PID: 4453 Comm: syzkaller932654 Not tainted 4.16.0+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b9/0x29f lib/dump_stack.c:53
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0xac/0x2f5 mm/kasan/report.c:412
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
 memcpy+0x37/0x50 mm/kasan/kasan.c:303
 strlcpy include/linux/string.h:300 [inline]
 ipip6_tunnel_locate+0x63b/0xaa0 net/ipv6/sit.c:254
 ipip6_tunnel_ioctl+0xe71/0x241b net/ipv6/sit.c:1221
 dev_ifsioc+0x43e/0xb90 net/core/dev_ioctl.c:334
 dev_ioctl+0x69a/0xcc0 net/core/dev_ioctl.c:525
 sock_ioctl+0x47e/0x680 net/socket.c:1015
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1cf/0x1650 fs/ioctl.c:684
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701
 SYSC_ioctl fs/ioctl.c:708 [inline]
 SyS_ioctl+0x24/0x30 fs/ioctl.c:706
 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-05 15:16:15 -04:00
Kirill Tkhai
2f635ceeb2 net: Drop pernet_operations::async
Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-27 13:18:09 -04:00
Eric Dumazet
79134e6ce2 net: do not create fallback tunnels for non-default namespaces
fallback tunnels (like tunl0, gre0, gretap0, erspan0, sit0,
ip6tnl0, ip6gre0) are automatically created when the corresponding
module is loaded.

These tunnels are also automatically created when a new network
namespace is created, at a great cost.

In many cases, netns are used for isolation purposes, and these
extra network devices are a waste of resources. We are using
thousands of netns per host, and hit the netns creation/delete
bottleneck a lot. (Many thanks to Kirill for recent work on this)

Add a new sysctl so that we can opt-out from this automatic creation.

Note that these tunnels are still created for the initial namespace,
to be the least intrusive for typical setups.

Tested:
lpk43:~# cat add_del_unshare.sh
for i in `seq 1 40`
do
 (for j in `seq 1 100` ; do  unshare -n /bin/true >/dev/null ; done) &
done
wait

lpk43:~# echo 0 >/proc/sys/net/core/fb_tunnels_only_for_init_net
lpk43:~# time ./add_del_unshare.sh

real	0m37.521s
user	0m0.886s
sys	7m7.084s
lpk43:~# echo 1 >/proc/sys/net/core/fb_tunnels_only_for_init_net
lpk43:~# time ./add_del_unshare.sh

real	0m4.761s
user	0m0.851s
sys	1m8.343s
lpk43:~#

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09 11:23:11 -05:00
David S. Miller
0f3e9c97eb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
All of the conflicts were cases of overlapping changes.

In net/core/devlink.c, we have to make care that the
resouce size_params have become a struct member rather
than a pointer to such an object.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-06 01:20:46 -05:00
Xin Long
2b3957c34b sit: fix IFLA_MTU ignored on NEWLINK
Commit 128bb975dc ("ip6_gre: init dev->mtu and dev->hard_header_len
correctly") fixed IFLA_MTU ignored on NEWLINK for ip6_gre. The same
mtu fix is also needed for sit.

Note that dev->hard_header_len setting for sit works fine, no need to
fix it. sit is actually ipv4 tunnel, it can't call ip6_tnl_change_mtu
to set mtu.

Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-27 14:36:28 -05:00