Most of code paths in tunnels are lockless (eg NETIF_F_LLTX in tx).
Adopt SMP safe DEV_STATS_{INC|ADD}() to update dev->stats fields.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
2871edb32f ("can: kvaser_usb: Fix possible completions during init_completion")
abb8670938 ("can: kvaser_usb_leaf: Ignore stale bus-off after start")
8d21f5927a ("can: kvaser_usb_leaf: Fix improved state not being reported")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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>
When the payload is a VLAN encapsulated IPv6/IPv6 frame, we can
skip the 802.1q/802.1ad ethertypes and jump to the actual protocol.
This way we treat IPv4/IPv6 frames as IP instead of as "other".
Signed-off-by: Matthias May <matthias.may@westermo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current code always forces a dscp of 0 for all non-IP frames.
However when setting a specific TOS with the command
ip link add name tep0 type ip6gretap local fdd1:ced0:5d88:3fce::1
remote fdd1:ced0:5d88:3fce::2 tos 0xa0
one would expect all GRE encapsulated frames to have a TOS of 0xA0.
and not only when the payload is IPv4/IPv6.
Signed-off-by: Matthias May <matthias.may@westermo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
Recently we made o_seqno atomic_t. Stop special-casing TUNNEL_SEQ, and
always mark IP6GRE[TAP] devices as NETIF_F_LLTX, since we no longer need
the TX lock (&txq->_xmit_lock).
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
As pointed out by Jakub Kicinski, currently using TUNNEL_SEQ in
collect_md mode is racy for [IP6]GRE[TAP] devices. Consider the
following sequence of events:
1. An [IP6]GRE[TAP] device is created in collect_md mode using "ip link
add ... external". "ip" ignores "[o]seq" if "external" is specified,
so TUNNEL_SEQ is off, and the device is marked as NETIF_F_LLTX (i.e.
it uses lockless TX);
2. Someone sets TUNNEL_SEQ on outgoing skb's, using e.g.
bpf_skb_set_tunnel_key() in an eBPF program attached to this device;
3. gre_fb_xmit() or __gre6_xmit() processes these skb's:
gre_build_header(skb, tun_hlen,
flags, protocol,
tunnel_id_to_key32(tun_info->key.tun_id),
(flags & TUNNEL_SEQ) ? htonl(tunnel->o_seqno++)
: 0); ^^^^^^^^^^^^^^^^^
Since we are not using the TX lock (&txq->_xmit_lock), multiple CPUs may
try to do this tunnel->o_seqno++ in parallel, which is racy. Fix it by
making o_seqno atomic_t.
As mentioned by Eric Dumazet in commit b790e01aee ("ip_gre: lockless
xmit"), making o_seqno atomic_t increases "chance for packets being out
of order at receiver" when NETIF_F_LLTX is on.
Maybe a better fix would be:
1. Do not ignore "oseq" in external mode. Users MUST specify "oseq" if
they want the kernel to allow sequencing of outgoing packets;
2. Reject all outgoing TUNNEL_SEQ packets if the device was not created
with "oseq".
Unfortunately, that would break userspace.
We could now make [IP6]GRE[TAP] devices always NETIF_F_LLTX, but let us
do it in separate patches to keep this fix minimal.
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Fixes: 77a5196a80 ("gre: add sequence number for collect md mode.")
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For IP6GRE and IP6GRETAP devices, currently o_seqno starts from 1 in
native mode. According to RFC 2890 2.2., "The first datagram is sent
with a sequence number of 0." Fix it.
It is worth mentioning that o_seqno already starts from 0 in collect_md
mode, see the "if (tunnel->parms.collect_md)" clause in __gre6_xmit(),
where tunnel->o_seqno is passed to gre_build_header() before getting
incremented.
Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Feng reported an skb_under_panic BUG triggered by running
test_ip6gretap() in tools/testing/selftests/bpf/test_tunnel.sh:
[ 82.492551] skbuff: skb_under_panic: text:ffffffffb268bb8e len:403 put:12 head:ffff9997c5480000 data:ffff9997c547fff8 tail:0x18b end:0x2c0 dev:ip6gretap11
<...>
[ 82.607380] Call Trace:
[ 82.609389] <TASK>
[ 82.611136] skb_push.cold.109+0x10/0x10
[ 82.614289] __gre6_xmit+0x41e/0x590
[ 82.617169] ip6gre_tunnel_xmit+0x344/0x3f0
[ 82.620526] dev_hard_start_xmit+0xf1/0x330
[ 82.623882] sch_direct_xmit+0xe4/0x250
[ 82.626961] __dev_queue_xmit+0x720/0xfe0
<...>
[ 82.633431] packet_sendmsg+0x96a/0x1cb0
[ 82.636568] sock_sendmsg+0x30/0x40
<...>
The following sequence of events caused the BUG:
1. During ip6gretap device initialization, tunnel->tun_hlen (e.g. 4) is
calculated based on old flags (see ip6gre_calc_hlen());
2. packet_snd() reserves header room for skb A, assuming
tunnel->tun_hlen is 4;
3. Later (in clsact Qdisc), the eBPF program sets a new tunnel key for
skb A using bpf_skb_set_tunnel_key() (see _ip6gretap_set_tunnel());
4. __gre6_xmit() detects the new tunnel key, and recalculates
"tun_hlen" (e.g. 12) based on new flags (e.g. TUNNEL_KEY and
TUNNEL_SEQ);
5. gre_build_header() calls skb_push() with insufficient reserved header
room, triggering the BUG.
As sugguested by Cong, fix it by moving the call to skb_cow_head() after
the recalculation of tun_hlen.
Reproducer:
OBJ=$LINUX/tools/testing/selftests/bpf/test_tunnel_kern.o
ip netns add at_ns0
ip link add veth0 type veth peer name veth1
ip link set veth0 netns at_ns0
ip netns exec at_ns0 ip addr add 172.16.1.100/24 dev veth0
ip netns exec at_ns0 ip link set dev veth0 up
ip link set dev veth1 up mtu 1500
ip addr add dev veth1 172.16.1.200/24
ip netns exec at_ns0 ip addr add ::11/96 dev veth0
ip netns exec at_ns0 ip link set dev veth0 up
ip addr add dev veth1 ::22/96
ip link set dev veth1 up
ip netns exec at_ns0 \
ip link add dev ip6gretap00 type ip6gretap seq flowlabel 0xbcdef key 2 \
local ::11 remote ::22
ip netns exec at_ns0 ip addr add dev ip6gretap00 10.1.1.100/24
ip netns exec at_ns0 ip addr add dev ip6gretap00 fc80::100/96
ip netns exec at_ns0 ip link set dev ip6gretap00 up
ip link add dev ip6gretap11 type ip6gretap external
ip addr add dev ip6gretap11 10.1.1.200/24
ip addr add dev ip6gretap11 fc80::200/24
ip link set dev ip6gretap11 up
tc qdisc add dev ip6gretap11 clsact
tc filter add dev ip6gretap11 egress bpf da obj $OBJ sec ip6gretap_set_tunnel
tc filter add dev ip6gretap11 ingress bpf da obj $OBJ sec ip6gretap_get_tunnel
ping6 -c 3 -w 10 -q ::11
Fixes: 6712abc168 ("ip6_gre: add ip6 gre and gretap collect_md mode")
Reported-by: Feng Zhou <zhoufeng.zf@bytedance.com>
Co-developed-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Do not update tunnel->tun_hlen in data plane code. Use a local variable
instead, just like "tunnel_hlen" in net/ipv4/ip_gre.c:gre_fb_xmit().
Co-developed-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On egress side, xfrm lookup is called from __gre6_xmit() with the
fl6_gre_key field not initialized leading to policies selectors check
failure. Consequently, gre packets are sent without encryption.
On ingress side, INET6_PROTO_NOPOLICY was set, thus packets were not
checked against xfrm policies. Like for egress side, fl6_gre_key should be
correctly set, this is now done in decode_session6().
Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Cc: stable@vger.kernel.org
Signed-off-by: Ghalem Boudour <ghalem.boudour@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This reverts commit 9cf448c200.
This commit was added for equivalence with a similar fix to ip_gre.
That fix proved to have a bug. Upon closer inspection, ip6_gre is not
susceptible to the original bug.
So revert the unnecessary extra check.
In short, ipgre_xmit calls skb_pull to remove ipv4 headers previously
inserted by dev_hard_header. ip6gre_tunnel_xmit does not.
Link: https://lore.kernel.org/netdev/CA+FuTSe+vJgTVLc9SojGuN-f9YQ+xWLPKE_S4f=f+w+_P2hgUg@mail.gmail.com/#t
Fixes: 9cf448c200 ("ip6_gre: add validation for csum_start")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Validate csum_start in gre_handle_offloads before we call _gre_xmit so
that we do not crash later when the csum_start value is used in the
lco_csum function call.
This patch deals with ipv6 code.
Fixes: Fixes: b05229f442 ("gre6: Cleanup GREv6 transmit path, call common
GRE functions")
Reported-by: syzbot+ff8e1b9f2f36481e2efc@syzkaller.appspotmail.com
Signed-off-by: Shreyansh Chouhan <chouhan.shreyansh630@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
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 dev_hold(),
and vice versa.
- 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.
ip6_gre for example (among others problematic drivers)
has to use dev_hold() in ip6gre_tunnel_init_common()
instead of from ip6gre_newlink_common(), covering
both ip6gre_tunnel_init() and ip6gre_tap_init()/
Note that ip6gre_tunnel_init_common() is not called from
ip6erspan_tap_init() thus we also need to add a dev_hold() there,
as ip6erspan_tunnel_uninit() does call dev_put()
[1]
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 0 PID: 8422 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Modules linked in:
CPU: 1 PID: 8422 Comm: syz-executor854 Not tainted 5.12.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Code: 1d 6a 5a e8 09 31 ff 89 de e8 8d 1a ab fd 84 db 75 e0 e8 d4 13 ab fd 48 c7 c7 a0 e1 c1 89 c6 05 4a 5a e8 09 01 e8 2e 36 fb 04 <0f> 0b eb c4 e8 b8 13 ab fd 0f b6 1d 39 5a e8 09 31 ff 89 de e8 58
RSP: 0018:ffffc900018befd0 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88801ef19c40 RSI: ffffffff815c51f5 RDI: fffff52000317dec
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815bdf8e R11: 0000000000000000 R12: ffff888018cf4568
R13: ffff888018cf4c00 R14: ffff8880228f2000 R15: ffffffff8d659b80
FS: 00000000014eb300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d7bf2b3138 CR3: 0000000014933000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__refcount_dec include/linux/refcount.h:344 [inline]
refcount_dec include/linux/refcount.h:359 [inline]
dev_put include/linux/netdevice.h:4135 [inline]
ip6gre_tunnel_uninit+0x3d7/0x440 net/ipv6/ip6_gre.c:420
register_netdevice+0xadf/0x1500 net/core/dev.c:10308
ip6gre_newlink_common.constprop.0+0x158/0x410 net/ipv6/ip6_gre.c:1984
ip6gre_newlink+0x275/0x7a0 net/ipv6/ip6_gre.c:2017
__rtnl_newlink+0x1062/0x1710 net/core/rtnetlink.c:3443
rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3491
rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5553
netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2502
netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338
netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1927
sock_sendmsg_nosec net/socket.c:654 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:674
____sys_sendmsg+0x6e8/0x810 net/socket.c:2350
___sys_sendmsg+0xf3/0x170 net/socket.c:2404
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2433
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
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>
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>
syzkaller managed to crash the kernel using an NBMA ip6gre interface. I
could reproduce it creating an NBMA ip6gre interface and forwarding
traffic to it:
skbuff: skb_under_panic: text:ffffffff8250e927 len:148 put:44 head:ffff8c03c7a33
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:109!
Call Trace:
skb_push+0x10/0x10
ip6gre_header+0x47/0x1b0
neigh_connected_output+0xae/0xf0
ip6gre tunnel provides its own header_ops->create, and sets it
conditionally when initializing the tunnel in NBMA mode. When
header_ops->create is used, dev->hard_header_len should reflect the
length of the header created. Otherwise, when not used,
dev->needed_headroom should be used.
Fixes: eb95f52fc7 ("net: ipv6_gre: Fix GRO to work on IPv6 over GRE tap")
Cc: Maria Pasechnik <mariap@mellanox.com>
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Link: https://lore.kernel.org/r/20201130161911.464106-1-atenart@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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>
similarly to what has been done with commit 9d149045b3 ("geneve: change
from tx_error to tx_dropped on missing metadata"), avoid reporting errors
to userspace in case the kernel doesn't find any tunnel information for a
skb that is going to be transmitted: an increase of tx_dropped is enough.
tested with the following script:
# for t in ip6gre ip6gretap ip6erspan; do
> ip link add dev gre6-test0 type $t external
> ip address add dev gre6-test0 2001:db8::1/64
> ip link set dev gre6-test0 up
> sleep 30
> ip -s -j link show dev gre6-test0 | jq \
> '.[0].stats64.tx | {"errors": .errors, "dropped": .dropped}'
> ip link del dev gre6-test0
> done
Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
KASAN report null-ptr-deref error when register_netdev() failed:
KASAN: null-ptr-deref in range [0x00000000000003c0-0x00000000000003c7]
CPU: 2 PID: 422 Comm: ip Not tainted 5.8.0-rc4+ #12
Call Trace:
ip6gre_init_net+0x4ab/0x580
? ip6gre_tunnel_uninit+0x3f0/0x3f0
ops_init+0xa8/0x3c0
setup_net+0x2de/0x7e0
? rcu_read_lock_bh_held+0xb0/0xb0
? ops_init+0x3c0/0x3c0
? kasan_unpoison_shadow+0x33/0x40
? __kasan_kmalloc.constprop.0+0xc2/0xd0
copy_net_ns+0x27d/0x530
create_new_namespaces+0x382/0xa30
unshare_nsproxy_namespaces+0xa1/0x1d0
ksys_unshare+0x39c/0x780
? walk_process_tree+0x2a0/0x2a0
? trace_hardirqs_on+0x4a/0x1b0
? _raw_spin_unlock_irq+0x1f/0x30
? syscall_trace_enter+0x1a7/0x330
? do_syscall_64+0x1c/0xa0
__x64_sys_unshare+0x2d/0x40
do_syscall_64+0x56/0xa0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
ip6gre_tunnel_uninit() has set 'ign->fb_tunnel_dev' to NULL, later
access to ign->fb_tunnel_dev cause null-ptr-deref. Fix it by saving
'ign->fb_tunnel_dev' to local variable ndev.
Fixes: dafabb6590 ("ip6_gre: fix use-after-free in ip6gre_tunnel_lookup()")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the datapath, the ip6gre_tunnel_lookup() is used and it internally uses
fallback tunnel device pointer, which is fb_tunnel_dev.
This pointer variable should be set to NULL when a fb interface is deleted.
But there is no routine to set fb_tunnel_dev pointer to NULL.
So, this pointer will be still used after interface is deleted and
it eventually results in the use-after-free problem.
Test commands:
ip netns add A
ip netns add B
ip link add eth0 type veth peer name eth1
ip link set eth0 netns A
ip link set eth1 netns B
ip netns exec A ip link set lo up
ip netns exec A ip link set eth0 up
ip netns exec A ip link add ip6gre1 type ip6gre local fc:0::1 \
remote fc:0::2
ip netns exec A ip -6 a a fc💯:1/64 dev ip6gre1
ip netns exec A ip link set ip6gre1 up
ip netns exec A ip -6 a a fc:0::1/64 dev eth0
ip netns exec A ip link set ip6gre0 up
ip netns exec B ip link set lo up
ip netns exec B ip link set eth1 up
ip netns exec B ip link add ip6gre1 type ip6gre local fc:0::2 \
remote fc:0::1
ip netns exec B ip -6 a a fc💯:2/64 dev ip6gre1
ip netns exec B ip link set ip6gre1 up
ip netns exec B ip -6 a a fc:0::2/64 dev eth1
ip netns exec B ip link set ip6gre0 up
ip netns exec A ping fc💯:2 -s 60000 &
ip netns del B
Splat looks like:
[ 73.087285][ C1] BUG: KASAN: use-after-free in ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre]
[ 73.088361][ C1] Read of size 4 at addr ffff888040559218 by task ping/1429
[ 73.089317][ C1]
[ 73.089638][ C1] CPU: 1 PID: 1429 Comm: ping Not tainted 5.7.0+ #602
[ 73.090531][ C1] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 73.091725][ C1] Call Trace:
[ 73.092160][ C1] <IRQ>
[ 73.092556][ C1] dump_stack+0x96/0xdb
[ 73.093122][ C1] print_address_description.constprop.6+0x2cc/0x450
[ 73.094016][ C1] ? ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre]
[ 73.094894][ C1] ? ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre]
[ 73.095767][ C1] ? ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre]
[ 73.096619][ C1] kasan_report+0x154/0x190
[ 73.097209][ C1] ? ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre]
[ 73.097989][ C1] ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre]
[ 73.098750][ C1] ? gre_del_protocol+0x60/0x60 [gre]
[ 73.099500][ C1] gre_rcv+0x1c5/0x1450 [ip6_gre]
[ 73.100199][ C1] ? ip6gre_header+0xf00/0xf00 [ip6_gre]
[ 73.100985][ C1] ? rcu_read_lock_sched_held+0xc0/0xc0
[ 73.101830][ C1] ? ip6_input_finish+0x5/0xf0
[ 73.102483][ C1] ip6_protocol_deliver_rcu+0xcbb/0x1510
[ 73.103296][ C1] ip6_input_finish+0x5b/0xf0
[ 73.103920][ C1] ip6_input+0xcd/0x2c0
[ 73.104473][ C1] ? ip6_input_finish+0xf0/0xf0
[ 73.105115][ C1] ? rcu_read_lock_held+0x90/0xa0
[ 73.105783][ C1] ? rcu_read_lock_sched_held+0xc0/0xc0
[ 73.106548][ C1] ipv6_rcv+0x1f1/0x300
[ ... ]
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Variables declared in a switch statement before any case statements
cannot be automatically initialized with compiler instrumentation (as
they are not part of any execution flow). With GCC's proposed automatic
stack variable initialization feature, this triggers a warning (and they
don't get initialized). Clang's automatic stack variable initialization
(via CONFIG_INIT_STACK_ALL=y) doesn't throw a warning, but it also
doesn't initialize such variables[1]. Note that these warnings (or silent
skipping) happen before the dead-store elimination optimization phase,
so even when the automatic initializations are later elided in favor of
direct initializations, the warnings remain.
To avoid these problems, move such variables into the "case" where
they're used or lift them up into the main function body.
net/ipv6/ip6_gre.c: In function ‘ip6gre_err’:
net/ipv6/ip6_gre.c:440:32: warning: statement will never be executed [-Wswitch-unreachable]
440 | struct ipv6_tlv_tnl_enc_lim *tel;
| ^~~
net/ipv6/ip6_tunnel.c: In function ‘ip6_tnl_err’:
net/ipv6/ip6_tunnel.c:520:32: warning: statement will never be executed [-Wswitch-unreachable]
520 | struct ipv6_tlv_tnl_enc_lim *tel;
| ^~~
[1] https://bugs.llvm.org/show_bug.cgi?id=44916
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Support for moving IPv4 GRE tunnels between namespaces was added in
commit b57708add3 ("gre: add x-netns support"). The respective change
for IPv6 tunnels, commit 22f08069e8 ("ip6gre: add x-netns support")
did not drop NETIF_F_NETNS_LOCAL flag so moving them from one netns to
another is still denied in IPv6 case. Drop NETIF_F_NETNS_LOCAL flag from
ip6gre tunnels to allow moving ip6gre tunnel endpoints between network
namespaces.
Signed-off-by: Niko Kortstrom <niko.kortstrom@nokia.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we do ipv6 gre pmtu update, we will also do neigh confirm currently.
This will cause the neigh cache be refreshed and set to REACHABLE before
xmit.
But if the remote mac address changed, e.g. device is deleted and recreated,
we will not able to notice this and still use the old mac address as the neigh
cache is REACHABLE.
Fix this by disable neigh confirm when do pmtu update
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.
Reported-by: Jianlin Shi <jishi@redhat.com>
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>
The MTU update code is supposed to be invoked in response to real
networking events that update the PMTU. In IPv6 PMTU update function
__ip6_rt_update_pmtu() we called dst_confirm_neigh() to update neighbor
confirmed time.
But for tunnel code, it will call pmtu before xmit, like:
- tnl_update_pmtu()
- skb_dst_update_pmtu()
- ip6_rt_update_pmtu()
- __ip6_rt_update_pmtu()
- dst_confirm_neigh()
If the tunnel remote dst mac address changed and we still do the neigh
confirm, we will not be able to update neigh cache and ping6 remote
will failed.
So for this ip_tunnel_xmit() case, _EVEN_ if the MTU is changed, we
should not be invoking dst_confirm_neigh() as we have no evidence
of successful two-way communication at this point.
On the other hand it is also important to keep the neigh reachability fresh
for TCP flows, so we cannot remove this dst_confirm_neigh() call.
To fix the issue, we have to add a new bool parameter for dst_ops.update_pmtu
to choose whether we should do neigh update or not. I will add the parameter
in this patch and set all the callers to true to comply with the previous
way, and fix the tunnel code one by one on later patches.
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.
Suggested-by: David Miller <davem@davemloft.net>
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>
Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except
at places where these are defined. Later patches will remove the unused
definition of FIELD_SIZEOF().
This patch is generated using following script:
EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h"
git grep -l -e "\bFIELD_SIZEOF\b" | while read file;
do
if [[ "$file" =~ $EXCLUDE_FILES ]]; then
continue
fi
sed -i -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file;
done
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: David Miller <davem@davemloft.net> # for net
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>
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>
In ip6erspan_tunnel_xmit(), if the skb will not be sent out, it has to
be freed on the tx_err path. Otherwise when deleting a netns, it would
cause dst/dev to leak, and dmesg shows:
unregister_netdevice: waiting for lo to become free. Usage count = 1
Fixes: ef7baf5e08 ("ip6_gre: add ip6 erspan collect_md mode")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since ip6_tnl_parse_tlv_enc_lim() can call pskb_may_pull()
which may change skb->data, so we need to re-load ipv6h at
the right place.
Fixes: 898b29798e ("ip6_gre: Refactor ip6gre xmit codes")
Cc: William Tu <u9012063@gmail.com>
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
erspan_v6 tunnels run __iptunnel_pull_header on received skbs to remove
erspan header. This can determine a possible use-after-free accessing
pkt_md pointer in ip6erspan_rcv 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). Fix it resetting pkt_md pointer after
__iptunnel_pull_header
Fixes: 1d7e2ed22f ("net: erspan: refactor existing erspan code")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Three conflicts, one of which, for marvell10g.c is non-trivial and
requires some follow-up from Heiner or someone else.
The issue is that Heiner converted the marvell10g driver over to
use the generic c45 code as much as possible.
However, in 'net' a bug fix appeared which makes sure that a new
local mask (MDIO_AN_10GBT_CTRL_ADV_NBT_MASK) with value 0x01e0
is cleared.
Signed-off-by: David S. Miller <davem@davemloft.net>
Report erspan version field to userspace in ip6gre_fill_info just for
erspan_v6 tunnels. Moreover report IFLA_GRE_ERSPAN_INDEX only for
erspan version 1.
The issue can be triggered with the following reproducer:
$ip link add name gre6 type ip6gre local 2001::1 remote 2002::2
$ip link set gre6 up
$ip -d link sh gre6
14: grep6@NONE: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1448 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/gre6 2001::1 peer 2002::2 promiscuity 0 minmtu 0 maxmtu 0
ip6gre remote 2002::2 local 2001::1 hoplimit 64 encaplimit 4 tclass 0x00 flowlabel 0x00000 erspan_index 0 erspan_ver 0 addrgenmode eui64
Fixes: 94d7d8f292 ("ip6_gre: add erspan v2 support")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit c706863bc8 ("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 84581bdae9 ("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: c706863bc8 ("net: ip6_gre: always reports o_key to userspace")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Reviewed-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
An ipvlan bug fix in 'net' conflicted with the abstraction away
of the IPV6 specific support in 'net-next'.
Similarly, a bug fix for mlx5 in 'net' conflicted with the flow
action conversion in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
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: <BROADCAST,MULTICAST> 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: 5a963eb61b ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet