<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/net/ipv4/ip_tunnel.c, branch linux-5.1.y</title>
<subtitle>Hosts the 0x221E linux distro kernel.</subtitle>
<id>https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-5.1.y</id>
<link rel='self' href='https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-5.1.y'/>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/'/>
<updated>2019-03-06T18:43:06Z</updated>
<entry>
<title>iptunnel: NULL pointer deref for ip_md_tunnel_xmit</title>
<updated>2019-03-06T18:43:06Z</updated>
<author>
<name>Alan Maguire</name>
<email>alan.maguire@oracle.com</email>
</author>
<published>2019-03-06T10:25:42Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=f4b3ec4e6aa1a2ca437905a519ae08e8cf6af754'/>
<id>urn:sha1:f4b3ec4e6aa1a2ca437905a519ae08e8cf6af754</id>
<content type='text'>
Naresh Kamboju noted the following oops during execution of selftest
tools/testing/selftests/bpf/test_tunnel.sh on x86_64:

[  274.120445] BUG: unable to handle kernel NULL pointer dereference
at 0000000000000000
[  274.128285] #PF error: [INSTR]
[  274.131351] PGD 8000000414a0e067 P4D 8000000414a0e067 PUD 3b6334067 PMD 0
[  274.138241] Oops: 0010 [#1] SMP PTI
[  274.141734] CPU: 1 PID: 11464 Comm: ping Not tainted
5.0.0-rc4-next-20190129 #1
[  274.149046] Hardware name: Supermicro SYS-5019S-ML/X11SSH-F, BIOS
2.0b 07/27/2017
[  274.156526] RIP: 0010:          (null)
[  274.160280] Code: Bad RIP value.
[  274.163509] RSP: 0018:ffffbc9681f83540 EFLAGS: 00010286
[  274.168726] RAX: 0000000000000000 RBX: ffffdc967fa80a18 RCX: 0000000000000000
[  274.175851] RDX: ffff9db2ee08b540 RSI: 000000000000000e RDI: ffffdc967fa809a0
[  274.182974] RBP: ffffbc9681f83580 R08: ffff9db2c4d62690 R09: 000000000000000c
[  274.190098] R10: 0000000000000000 R11: ffff9db2ee08b540 R12: ffff9db31ce7c000
[  274.197222] R13: 0000000000000001 R14: 000000000000000c R15: ffff9db3179cf400
[  274.204346] FS:  00007ff4ae7c5740(0000) GS:ffff9db31fa80000(0000)
knlGS:0000000000000000
[  274.212424] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  274.218162] CR2: ffffffffffffffd6 CR3: 00000004574da004 CR4: 00000000003606e0
[  274.225292] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  274.232416] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  274.239541] Call Trace:
[  274.241988]  ? tnl_update_pmtu+0x296/0x3b0
[  274.246085]  ip_md_tunnel_xmit+0x1bc/0x520
[  274.250176]  gre_fb_xmit+0x330/0x390
[  274.253754]  gre_tap_xmit+0x128/0x180
[  274.257414]  dev_hard_start_xmit+0xb7/0x300
[  274.261598]  sch_direct_xmit+0xf6/0x290
[  274.265430]  __qdisc_run+0x15d/0x5e0
[  274.269007]  __dev_queue_xmit+0x2c5/0xc00
[  274.273011]  ? dev_queue_xmit+0x10/0x20
[  274.276842]  ? eth_header+0x2b/0xc0
[  274.280326]  dev_queue_xmit+0x10/0x20
[  274.283984]  ? dev_queue_xmit+0x10/0x20
[  274.287813]  arp_xmit+0x1a/0xf0
[  274.290952]  arp_send_dst.part.19+0x46/0x60
[  274.295138]  arp_solicit+0x177/0x6b0
[  274.298708]  ? mod_timer+0x18e/0x440
[  274.302281]  neigh_probe+0x57/0x70
[  274.305684]  __neigh_event_send+0x197/0x2d0
[  274.309862]  neigh_resolve_output+0x18c/0x210
[  274.314212]  ip_finish_output2+0x257/0x690
[  274.318304]  ip_finish_output+0x219/0x340
[  274.322314]  ? ip_finish_output+0x219/0x340
[  274.326493]  ip_output+0x76/0x240
[  274.329805]  ? ip_fragment.constprop.53+0x80/0x80
[  274.334510]  ip_local_out+0x3f/0x70
[  274.337992]  ip_send_skb+0x19/0x40
[  274.341391]  ip_push_pending_frames+0x33/0x40
[  274.345740]  raw_sendmsg+0xc15/0x11d0
[  274.349403]  ? __might_fault+0x85/0x90
[  274.353151]  ? _copy_from_user+0x6b/0xa0
[  274.357070]  ? rw_copy_check_uvector+0x54/0x130
[  274.361604]  inet_sendmsg+0x42/0x1c0
[  274.365179]  ? inet_sendmsg+0x42/0x1c0
[  274.368937]  sock_sendmsg+0x3e/0x50
[  274.372460]  ___sys_sendmsg+0x26f/0x2d0
[  274.376293]  ? lock_acquire+0x95/0x190
[  274.380043]  ? __handle_mm_fault+0x7ce/0xb70
[  274.384307]  ? lock_acquire+0x95/0x190
[  274.388053]  ? __audit_syscall_entry+0xdd/0x130
[  274.392586]  ? ktime_get_coarse_real_ts64+0x64/0xc0
[  274.397461]  ? __audit_syscall_entry+0xdd/0x130
[  274.401989]  ? trace_hardirqs_on+0x4c/0x100
[  274.406173]  __sys_sendmsg+0x63/0xa0
[  274.409744]  ? __sys_sendmsg+0x63/0xa0
[  274.413488]  __x64_sys_sendmsg+0x1f/0x30
[  274.417405]  do_syscall_64+0x55/0x190
[  274.421064]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  274.426113] RIP: 0033:0x7ff4ae0e6e87
[  274.429686] Code: 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 80 00
00 00 00 8b 05 ca d9 2b 00 48 63 d2 48 63 ff 85 c0 75 10 b8 2e 00 00
00 0f 05 &lt;48&gt; 3d 00 f0 ff ff 77 51 c3 53 48 89 f3 48 83 ec 10 48 89 7c
24 08
[  274.448422] RSP: 002b:00007ffcd9b76db8 EFLAGS: 00000246 ORIG_RAX:
000000000000002e
[  274.455978] RAX: ffffffffffffffda RBX: 0000000000000040 RCX: 00007ff4ae0e6e87
[  274.463104] RDX: 0000000000000000 RSI: 00000000006092e0 RDI: 0000000000000003
[  274.470228] RBP: 0000000000000000 R08: 00007ffcd9bc40a0 R09: 00007ffcd9bc4080
[  274.477349] R10: 000000000000060a R11: 0000000000000246 R12: 0000000000000003
[  274.484475] R13: 0000000000000016 R14: 00007ffcd9b77fa0 R15: 00007ffcd9b78da4
[  274.491602] Modules linked in: cls_bpf sch_ingress iptable_filter
ip_tables algif_hash af_alg x86_pkg_temp_thermal fuse [last unloaded:
test_bpf]
[  274.504634] CR2: 0000000000000000
[  274.507976] ---[ end trace 196d18386545eae1 ]---
[  274.512588] RIP: 0010:          (null)
[  274.516334] Code: Bad RIP value.
[  274.519557] RSP: 0018:ffffbc9681f83540 EFLAGS: 00010286
[  274.524775] RAX: 0000000000000000 RBX: ffffdc967fa80a18 RCX: 0000000000000000
[  274.531921] RDX: ffff9db2ee08b540 RSI: 000000000000000e RDI: ffffdc967fa809a0
[  274.539082] RBP: ffffbc9681f83580 R08: ffff9db2c4d62690 R09: 000000000000000c
[  274.546205] R10: 0000000000000000 R11: ffff9db2ee08b540 R12: ffff9db31ce7c000
[  274.553329] R13: 0000000000000001 R14: 000000000000000c R15: ffff9db3179cf400
[  274.560456] FS:  00007ff4ae7c5740(0000) GS:ffff9db31fa80000(0000)
knlGS:0000000000000000
[  274.568541] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  274.574277] CR2: ffffffffffffffd6 CR3: 00000004574da004 CR4: 00000000003606e0
[  274.581403] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  274.588535] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  274.595658] Kernel panic - not syncing: Fatal exception in interrupt
[  274.602046] Kernel Offset: 0x14400000 from 0xffffffff81000000
(relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[  274.612827] ---[ end Kernel panic - not syncing: Fatal exception in
interrupt ]---
[  274.620387] ------------[ cut here ]------------

I'm also seeing the same failure on x86_64, and it reproduces
consistently.

&gt;From poking around it looks like the skb's dst entry is being used
to calculate the mtu in:

mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev-&gt;mtu;

...but because that dst_entry  has an "ops" value set to md_dst_ops,
the various ops (including mtu) are not set:

crash&gt; struct sk_buff._skb_refdst ffff928f87447700 -x
      _skb_refdst = 0xffffcd6fbf5ea590
crash&gt; struct dst_entry.ops 0xffffcd6fbf5ea590
  ops = 0xffffffffa0193800
crash&gt; struct dst_ops.mtu 0xffffffffa0193800
  mtu = 0x0
crash&gt;

I confirmed that the dst entry also has dst-&gt;input set to
dst_md_discard, so it looks like it's an entry that's been
initialized via __metadata_dst_init alright.

I think the fix here is to use skb_valid_dst(skb) - it checks
for  DST_METADATA also, and with that fix in place, the
problem - which was previously 100% reproducible - disappears.

The below patch resolves the panic and all bpf tunnel tests pass
without incident.

Fixes: c8b34e680a09 ("ip_tunnel: Add tnl_update_pmtu in ip_md_tunnel_xmit")
Reported-by: Naresh Kamboju &lt;naresh.kamboju@linaro.org&gt;
Signed-off-by: Alan Maguire &lt;alan.maguire@oracle.com&gt;
Acked-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Tested-by: Anders Roxell &lt;anders.roxell@linaro.org&gt;
Reported-by: Nicolas Dichtel &lt;nicolas.dichtel@6wind.com&gt;
Tested-by: Nicolas Dichtel &lt;nicolas.dichtel@6wind.com&gt;
Acked-by: Nicolas Dichtel &lt;nicolas.dichtel@6wind.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>route: Add multipath_hash in flowi_common to make user-define hash</title>
<updated>2019-02-27T20:50:17Z</updated>
<author>
<name>wenxu</name>
<email>wenxu@ucloud.cn</email>
</author>
<published>2019-02-24T03:36:20Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=24ba14406c5c8e33fcbe064f77b3ab01b84ec830'/>
<id>urn:sha1:24ba14406c5c8e33fcbe064f77b3ab01b84ec830</id>
<content type='text'>
Current fib_multipath_hash_policy can make hash based on the L3 or
L4. But it only work on the outer IP. So a specific tunnel always
has the same hash value. But a specific tunnel may contain so many
inner connections.

This patch provide a generic multipath_hash in floi_common. It can
make a user-define hash which can mix with L3 or L4 hash.

Signed-off-by: wenxu &lt;wenxu@ucloud.cn&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>ip_tunnel: Add ip tunnel tun_info type dst_cache in ip_tunnel_xmit</title>
<updated>2019-02-25T06:22:33Z</updated>
<author>
<name>wenxu</name>
<email>wenxu@ucloud.cn</email>
</author>
<published>2019-02-24T00:24:45Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=186d93669fe0cba252d42a42ddcfdbe9f2ee101d'/>
<id>urn:sha1:186d93669fe0cba252d42a42ddcfdbe9f2ee101d</id>
<content type='text'>
ip l add dev tun type gretap key 1000

Non-tunnel-dst ip tunnel device can send packet through lwtunnel
This patch provide the tun_inf dst cache support for this mode.

Signed-off-by: wenxu &lt;wenxu@ucloud.cn&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</title>
<updated>2019-01-27T18:43:17Z</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2019-01-27T18:43:17Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=1d68101367a92336e633d0c3681bf8c86644e124'/>
<id>urn:sha1:1d68101367a92336e633d0c3681bf8c86644e124</id>
<content type='text'>
</content>
</entry>
<entry>
<title>ip_tunnel: Fix route fl4 init in ip_md_tunnel_xmit</title>
<updated>2019-01-26T17:43:03Z</updated>
<author>
<name>wenxu</name>
<email>wenxu@ucloud.cn</email>
</author>
<published>2019-01-22T10:39:51Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=6e6b904ad4f9aed43ec320afbd5a52ed8461ab41'/>
<id>urn:sha1:6e6b904ad4f9aed43ec320afbd5a52ed8461ab41</id>
<content type='text'>
Init the gre_key from tuninfo-&gt;key.tun_id and init the mark
from the skb-&gt;mark, set the oif to zero in the collect metadata
mode.

Fixes: cfc7381b3002 ("ip_tunnel: add collect_md mode to IPIP tunnel")
Signed-off-by: wenxu &lt;wenxu@ucloud.cn&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>ip_tunnel: Add tnl_update_pmtu in ip_md_tunnel_xmit</title>
<updated>2019-01-26T17:43:03Z</updated>
<author>
<name>wenxu</name>
<email>wenxu@ucloud.cn</email>
</author>
<published>2019-01-22T10:39:50Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=c8b34e680a090ab8dc42f8331020e31052b49a70'/>
<id>urn:sha1:c8b34e680a090ab8dc42f8331020e31052b49a70</id>
<content type='text'>
Add tnl_update_pmtu in ip_md_tunnel_xmit to dynamic modify
the pmtu which packet send through collect_metadata mode
ip tunnel

Signed-off-by: wenxu &lt;wenxu@ucloud.cn&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>ip_tunnel: Add ip tunnel dst_cache in ip_md_tunnel_xmit</title>
<updated>2019-01-26T17:43:03Z</updated>
<author>
<name>wenxu</name>
<email>wenxu@ucloud.cn</email>
</author>
<published>2019-01-22T10:39:49Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=f46fe4f8d787bd66005120460317939b8c6d7c70'/>
<id>urn:sha1:f46fe4f8d787bd66005120460317939b8c6d7c70</id>
<content type='text'>
Add ip tunnel dst cache in ip_md_tunnel_xmit to make more
efficient for the route lookup.

Signed-off-by: wenxu &lt;wenxu@ucloud.cn&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>ip_tunnel: Make none-tunnel-dst tunnel port work with lwtunnel</title>
<updated>2019-01-25T01:54:12Z</updated>
<author>
<name>wenxu</name>
<email>wenxu@ucloud.cn</email>
</author>
<published>2019-01-19T05:11:25Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=d71b57532d70c03f4671dd04e84157ac6bf021b0'/>
<id>urn:sha1:d71b57532d70c03f4671dd04e84157ac6bf021b0</id>
<content type='text'>
ip l add dev tun type gretap key 1000
ip a a dev tun 10.0.0.1/24

Packets with tun-id 1000 can be recived by tun dev. But packet can't
be sent through dev tun for non-tunnel-dst

With this patch: tunnel-dst can be get through lwtunnel like beflow:
ip r a 10.0.0.7 encap ip dst 172.168.0.11 dev tun

Signed-off-by: wenxu &lt;wenxu@ucloud.cn&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>ip: validate header length on virtual device xmit</title>
<updated>2019-01-01T20:05:02Z</updated>
<author>
<name>Willem de Bruijn</name>
<email>willemb@google.com</email>
</author>
<published>2018-12-30T22:24:36Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=cb9f1b783850b14cbd7f87d061d784a666dfba1f'/>
<id>urn:sha1:cb9f1b783850b14cbd7f87d061d784a666dfba1f</id>
<content type='text'>
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 76c0ddd8c3a6 ("ip6_tunnel: be careful when accessing the
inner header") and commit ccfec9e5cb2d ("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 &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>ip_tunnel: be careful when accessing the inner header</title>
<updated>2018-09-24T19:27:04Z</updated>
<author>
<name>Paolo Abeni</name>
<email>pabeni@redhat.com</email>
</author>
<published>2018-09-24T13:48:19Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=ccfec9e5cb2d48df5a955b7bf47f7782157d3bc2'/>
<id>urn:sha1:ccfec9e5cb2d48df5a955b7bf47f7782157d3bc2</id>
<content type='text'>
Cong noted that we need the same checks introduced by commit 76c0ddd8c3a6
("ip6_tunnel: be careful when accessing the inner header")
even for ipv4 tunnels.

Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.")
Suggested-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
</feed>
