Don't hardcode a MTU value on vti tunnel initialization,
ip_tunnel_newlink() is able to deal with this already. See also
commit ffc2b6ee41 ("ip_gre: fix IFLA_MTU ignored on NEWLINK").
Fixes: 1181412c1a ("net/ipv4: VTI support new module for ip_vti.")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This re-introduces the effect of commit a32452366b ("vti4:
Don't count header length twice.") which was accidentally
reverted by merge commit f895f0cfbb ("Merge branch 'master' of
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec").
The commit message from Steffen Klassert said:
We currently count the size of LL_MAX_HEADER and struct iphdr
twice for vti4 devices, this leads to a wrong device mtu.
The size of LL_MAX_HEADER and struct iphdr is already counted in
ip_tunnel_bind_dev(), so don't do it again in vti_tunnel_init().
And this is still the case now: ip_tunnel_bind_dev() already
accounts for the header length of the link layer (not
necessarily LL_MAX_HEADER, if the output device is found), plus
one IP header.
For example, with a vti device on top of veth, with MTU of 1500,
the existing implementation would set the initial vti MTU to
1332, accounting once for LL_MAX_HEADER (128, included in
hard_header_len by vti) and twice for the same IP header (once
from hard_header_len, once from ip_tunnel_bind_dev()).
It should instead be 1480, because ip_tunnel_bind_dev() is able
to figure out that the output device is veth, so no additional
link layer header is attached, and will properly count one
single IP header.
The existing issue had the side effect of avoiding PMTUD for
most xfrm policies, by arbitrarily lowering the initial MTU.
However, the only way to get a consistent PMTU value is to let
the xfrm PMTU discovery do its course, and commit d6af1a31cc
("vti: Add pmtu handling to vti_xmit.") now takes care of local
delivery cases where the application ignores local socket
notifications.
Fixes: b9959fd3b0 ("vti: switch to new ip tunnel code")
Fixes: f895f0cfbb ("Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Some dst_ops (e.g. md_dst_ops)) doesn't set this handler. It may result to:
"BUG: unable to handle kernel NULL pointer dereference at (null)"
Let's add a helper to check if update_pmtu is available before calling it.
Fixes: 52a589d51f ("geneve: update skb dst pmtu on tx path")
Fixes: a93bf0ff44 ("vxlan: update skb dst pmtu on tx path")
CC: Roman Kapl <code@rkapl.cz>
CC: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unlike ipip and gre, ip_vti never uses err_count in vti4_err,
so no need to check err_count in vti_xmit, it's value always 0.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When running LTP IPsec tests, KASan might report:
BUG: KASAN: use-after-free in vti_tunnel_xmit+0xeee/0xff0 [ip_vti]
Read of size 4 at addr ffff880dc6ad1980 by task swapper/0/0
...
Call Trace:
<IRQ>
dump_stack+0x63/0x89
print_address_description+0x7c/0x290
kasan_report+0x28d/0x370
? vti_tunnel_xmit+0xeee/0xff0 [ip_vti]
__asan_report_load4_noabort+0x19/0x20
vti_tunnel_xmit+0xeee/0xff0 [ip_vti]
? vti_init_net+0x190/0x190 [ip_vti]
? save_stack_trace+0x1b/0x20
? save_stack+0x46/0xd0
dev_hard_start_xmit+0x147/0x510
? icmp_echo.part.24+0x1f0/0x210
__dev_queue_xmit+0x1394/0x1c60
...
Freed by task 0:
save_stack_trace+0x1b/0x20
save_stack+0x46/0xd0
kasan_slab_free+0x70/0xc0
kmem_cache_free+0x81/0x1e0
kfree_skbmem+0xb1/0xe0
kfree_skb+0x75/0x170
kfree_skb_list+0x3e/0x60
__dev_queue_xmit+0x1298/0x1c60
dev_queue_xmit+0x10/0x20
neigh_resolve_output+0x3a8/0x740
ip_finish_output2+0x5c0/0xe70
ip_finish_output+0x4ba/0x680
ip_output+0x1c1/0x3a0
xfrm_output_resume+0xc65/0x13d0
xfrm_output+0x1e4/0x380
xfrm4_output_finish+0x5c/0x70
Can be fixed if we get skb->len before dst_output().
Fixes: b9959fd3b0 ("vti: switch to new ip tunnel code")
Fixes: 22e1b23daf ("vti6: Support inter address family tunneling.")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This feature allows the administrator to set an fwmark for
packets traversing a tunnel. This allows the use of independent
routing tables for tunneled packets without the use of iptables.
There is no concept of per-packet routing decisions through IPv4
tunnels, so this implementation does not need to work with
per-packet route lookups as the v6 implementation may
(with IP6_TNL_F_USE_ORIG_FWMARK).
Further, since the v4 tunnel ioctls share datastructures
(which can not be trivially modified) with the kernel's internal
tunnel configuration structures, the mark attribute must be stored
in the tunnel structure itself and passed as a parameter when
creating or changing tunnel attributes.
Signed-off-by: Craig Gallek <kraig@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make struct pernet_operations::id unsigned.
There are 2 reasons to do so:
1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.
2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.
"int" being used as an array index needs to be sign-extended
to 64-bit before being used.
void f(long *p, int i)
{
g(p[i]);
}
roughly translates to
movsx rsi, esi
mov rdi, [rsi+...]
call g
MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.
Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:
static inline void *net_generic(const struct net *net, int id)
{
...
ptr = ng->ptr[id - 1];
...
}
And this function is used a lot, so those sign extensions add up.
Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):
add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]
However, overall balance is in negative direction:
add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
function old new delta
nfsd4_lock 3886 3959 +73
tipc_link_build_proto_msg 1096 1140 +44
mac80211_hwsim_new_radio 2776 2808 +32
tipc_mon_rcv 1032 1058 +26
svcauth_gss_legacy_init 1413 1429 +16
tipc_bcbase_select_primary 379 392 +13
nfsd4_exchange_id 1247 1260 +13
nfsd4_setclientid_confirm 782 793 +11
...
put_client_renew_locked 494 480 -14
ip_set_sockfn_get 730 716 -14
geneve_sock_add 829 813 -16
nfsd4_sequence_done 721 703 -18
nlmclnt_lookup_host 708 686 -22
nfsd4_lockt 1085 1063 -22
nfs_get_client 1077 1050 -27
tcf_bpf_init 1106 1076 -30
nfsd4_encode_fattr 5997 5930 -67
Total: Before=154856051, After=154854321, chg -0.00%
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case of inter address family tunneling (IPv6 over vti4 or IPv4 over
vti6), the inbound policy checks in vti_rcv_cb() and vti6_rcv_cb() are
using the wrong address family. As a result, all inbound inter address
family traffic is dropped.
Use the xfrm_ip2inner_mode() helper, as done in xfrm_input() (i.e., also
increment LINUX_MIB_XFRMINSTATEMODEERROR in case of error), to select the
inner_mode that contains the right address family for the inbound policy
checks.
Signed-off-by: Thomas Zeitlhofer <thomas.zeitlhofer+lkml@ze-it.at>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
When executing the script included below, the netns delete operation
hangs with the following message (repeated at 10 second intervals):
kernel:unregister_netdevice: waiting for lo to become free. Usage count = 1
This occurs because a reference to the lo interface in the "secure" netns
is still held by a dst entry in the xfrm bundle cache in the init netns.
Address this problem by garbage collecting the tunnel netns flow cache
when a cross-namespace vti interface receives a NETDEV_DOWN notification.
A more detailed description of the problem scenario (referencing commands
in the script below):
(1) ip link add vti_test type vti local 1.1.1.1 remote 1.1.1.2 key 1
The vti_test interface is created in the init namespace. vti_tunnel_init()
attaches a struct ip_tunnel to the vti interface's netdev_priv(dev),
setting the tunnel net to &init_net.
(2) ip link set vti_test netns secure
The vti_test interface is moved to the "secure" netns. Note that
the associated struct ip_tunnel still has tunnel->net set to &init_net.
(3) ip netns exec secure ping -c 4 -i 0.02 -I 192.168.100.1 192.168.200.1
The first packet sent using the vti device causes xfrm_lookup() to be
called as follows:
dst = xfrm_lookup(tunnel->net, skb_dst(skb), fl, NULL, 0);
Note that tunnel->net is the init namespace, while skb_dst(skb) references
the vti_test interface in the "secure" namespace. The returned dst
references an interface in the init namespace.
Also note that the first parameter to xfrm_lookup() determines which flow
cache is used to store the computed xfrm bundle, so after xfrm_lookup()
returns there will be a cached bundle in the init namespace flow cache
with a dst referencing a device in the "secure" namespace.
(4) ip netns del secure
Kernel begins to delete the "secure" namespace. At some point the
vti_test interface is deleted, at which point dst_ifdown() changes
the dst->dev in the cached xfrm bundle flow from vti_test to lo (still
in the "secure" namespace however).
Since nothing has happened to cause the init namespace's flow cache
to be garbage collected, this dst remains attached to the flow cache,
so the kernel loops waiting for the last reference to lo to go away.
<Begin script>
ip link add br1 type bridge
ip link set dev br1 up
ip addr add dev br1 1.1.1.1/8
ip netns add secure
ip link add vti_test type vti local 1.1.1.1 remote 1.1.1.2 key 1
ip link set vti_test netns secure
ip netns exec secure ip link set vti_test up
ip netns exec secure ip link s lo up
ip netns exec secure ip addr add dev lo 192.168.100.1/24
ip netns exec secure ip route add 192.168.200.0/24 dev vti_test
ip xfrm policy flush
ip xfrm state flush
ip xfrm policy add dir out tmpl src 1.1.1.1 dst 1.1.1.2 \
proto esp mode tunnel mark 1
ip xfrm policy add dir in tmpl src 1.1.1.2 dst 1.1.1.1 \
proto esp mode tunnel mark 1
ip xfrm state add src 1.1.1.1 dst 1.1.1.2 proto esp spi 1 \
mode tunnel enc des3_ede 0x112233445566778811223344556677881122334455667788
ip xfrm state add src 1.1.1.2 dst 1.1.1.1 proto esp spi 1 \
mode tunnel enc des3_ede 0x112233445566778811223344556677881122334455667788
ip netns exec secure ping -c 4 -i 0.02 -I 192.168.100.1 192.168.200.1
ip netns del secure
<End script>
Reported-by: Hangbin Liu <haliu@redhat.com>
Reported-by: Jan Tluka <jtluka@redhat.com>
Signed-off-by: Lance Richardson <lrichard@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently rely on the PMTU discovery of xfrm.
However if a packet is locally sent, the PMTU mechanism
of xfrm tries to do local socket notification what
might not work for applications like ping that don't
check for this. So add pmtu handling to vti_xmit to
report MTU changes immediately.
Reported-by: Mark McKinstry <Mark.McKinstry@alliedtelesis.co.nz>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
By moving stats update into iptunnel_xmit(), we can simplify
iptunnel_xmit() usage. With this change there is no need to
call another function (iptunnel_xmit_stats()) to update stats
in tunnel xmit code path.
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a sock paramter to dst_output making dst_output_sk superfluous.
Add a skb->sk parameter to all of the callers of dst_output
Have the callers of dst_output_sk call dst_output.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The vti6_rcv_cb and vti_rcv_cb calls were leaving the skb->mark modified
after completing the function. This resulted in the original skb->mark
value being lost. Since we only need skb->mark to be set for
xfrm_policy_check we can pull the assignment into the rcv_cb calls and then
just restore the original mark after xfrm_policy_check has been completed.
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Maciej Żenczykowski
Haishuang Yan
Stefano Brivio
Nicolas Dichtel
Xin Long
David S. Miller
Alexey Kodanev
Eric Dumazet
Florian Westphal
Matthias Schiffer
Hangbin Liu
Craig Gallek
Alexey Dobriyan
thomas.zeitlhofer+lkml@ze-it.at
Lance Richardson
Steffen Klassert
Pravin B Shelar
Nikolay Aleksandrov
Eric W. Biederman
Alexander Duyck