<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include/linux/skbuff.h, branch v4.19.41</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.19.41</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.19.41'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2019-03-23T19:10:06Z</updated>
<entry>
<title>bpf: only test gso type on gso packets</title>
<updated>2019-03-23T19:10:06Z</updated>
<author>
<name>Willem de Bruijn</name>
<email>willemb@google.com</email>
</author>
<published>2019-03-06T19:35:15Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=9920eb4003c5e0f1447c2125c5c8e101b5ad8b8f'/>
<id>urn:sha1:9920eb4003c5e0f1447c2125c5c8e101b5ad8b8f</id>
<content type='text'>
[ Upstream commit 4c3024debf62de4c6ac6d3cb4c0063be21d4f652 ]

BPF can adjust gso only for tcp bytestreams. Fail on other gso types.

But only on gso packets. It does not touch this field if !gso_size.

Fixes: b90efd225874 ("bpf: only adjust gso_size on bytestream protocols")
Signed-off-by: Willem de Bruijn &lt;willemb@google.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>bpf: only adjust gso_size on bytestream protocols</title>
<updated>2019-03-23T19:09:48Z</updated>
<author>
<name>Willem de Bruijn</name>
<email>willemb@google.com</email>
</author>
<published>2019-02-07T19:54:16Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=413e398520823d1a583bd35053e8472764310795'/>
<id>urn:sha1:413e398520823d1a583bd35053e8472764310795</id>
<content type='text'>
[ Upstream commit b90efd2258749e04e1b3f71ef0d716f2ac2337e0 ]

bpf_skb_change_proto and bpf_skb_adjust_room change skb header length.
For GSO packets they adjust gso_size to maintain the same MTU.

The gso size can only be safely adjusted on bytestream protocols.
Commit d02f51cbcf12 ("bpf: fix bpf_skb_adjust_net/bpf_skb_proto_xlat
to deal with gso sctp skbs") excluded SKB_GSO_SCTP.

Since then type SKB_GSO_UDP_L4 has been added, whose contents are one
gso_size unit per datagram. Also exclude these.

Move from a blacklist to a whitelist check to future proof against
additional such new GSO types, e.g., for fraglist based GRO.

Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT")
Signed-off-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: validate untrusted gso packets without csum offload</title>
<updated>2019-02-27T09:09:01Z</updated>
<author>
<name>Willem de Bruijn</name>
<email>willemb@google.com</email>
</author>
<published>2019-02-15T17:15:47Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=e93384b12443c9bb6830b56b7d299beed432b865'/>
<id>urn:sha1:e93384b12443c9bb6830b56b7d299beed432b865</id>
<content type='text'>
commit d5be7f632bad0f489879eed0ff4b99bd7fe0b74c upstream.

Syzkaller again found a path to a kernel crash through bad gso input.
By building an excessively large packet to cause an skb field to wrap.

If VIRTIO_NET_HDR_F_NEEDS_CSUM was set this would have been dropped in
skb_partial_csum_set.

GSO packets that do not set checksum offload are suspicious and rare.
Most callers of virtio_net_hdr_to_skb already pass them to
skb_probe_transport_header.

Move that test forward, change it to detect parse failure and drop
packets on failure as those cleary are not one of the legitimate
VIRTIO_NET_HDR_GSO types.

Fixes: bfd5f4a3d605 ("packet: Add GSO/csum offload support.")
Fixes: f43798c27684 ("tun: Allow GSO using virtio_net_hdr")
Reported-by: syzbot &lt;syzkaller@googlegroups.com&gt;
Signed-off-by: Willem de Bruijn &lt;willemb@google.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>net: Fix usage of pskb_trim_rcsum</title>
<updated>2019-01-31T07:14:31Z</updated>
<author>
<name>Ross Lagerwall</name>
<email>ross.lagerwall@citrix.com</email>
</author>
<published>2019-01-17T15:34:38Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=40f2f08030fa59f634ed8313f4c9578416f2a108'/>
<id>urn:sha1:40f2f08030fa59f634ed8313f4c9578416f2a108</id>
<content type='text'>
[ Upstream commit 6c57f0458022298e4da1729c67bd33ce41c14e7a ]

In certain cases, pskb_trim_rcsum() may change skb pointers.
Reinitialize header pointers afterwards to avoid potential
use-after-frees. Add a note in the documentation of
pskb_trim_rcsum(). Found by KASAN.

Signed-off-by: Ross Lagerwall &lt;ross.lagerwall@citrix.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net: use skb_list_del_init() to remove from RX sublists</title>
<updated>2018-12-17T08:24:27Z</updated>
<author>
<name>Edward Cree</name>
<email>ecree@solarflare.com</email>
</author>
<published>2018-12-04T17:37:57Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=7fafda16bb64c134658ffde0ac9332d23ba26fd0'/>
<id>urn:sha1:7fafda16bb64c134658ffde0ac9332d23ba26fd0</id>
<content type='text'>
[ Upstream commit 22f6bbb7bcfcef0b373b0502a7ff390275c575dd ]

list_del() leaves the skb-&gt;next pointer poisoned, which can then lead to
 a crash in e.g. OVS forwarding.  For example, setting up an OVS VXLAN
 forwarding bridge on sfc as per:

========
$ ovs-vsctl show
5dfd9c47-f04b-4aaa-aa96-4fbb0a522a30
    Bridge "br0"
        Port "br0"
            Interface "br0"
                type: internal
        Port "enp6s0f0"
            Interface "enp6s0f0"
        Port "vxlan0"
            Interface "vxlan0"
                type: vxlan
                options: {key="1", local_ip="10.0.0.5", remote_ip="10.0.0.4"}
    ovs_version: "2.5.0"
========
(where 10.0.0.5 is an address on enp6s0f1)
and sending traffic across it will lead to the following panic:
========
general protection fault: 0000 [#1] SMP PTI
CPU: 5 PID: 0 Comm: swapper/5 Not tainted 4.20.0-rc3-ehc+ #701
Hardware name: Dell Inc. PowerEdge R710/0M233H, BIOS 6.4.0 07/23/2013
RIP: 0010:dev_hard_start_xmit+0x38/0x200
Code: 53 48 89 fb 48 83 ec 20 48 85 ff 48 89 54 24 08 48 89 4c 24 18 0f 84 ab 01 00 00 48 8d 86 90 00 00 00 48 89 f5 48 89 44 24 10 &lt;4c&gt; 8b 33 48 c7 03 00 00 00 00 48 8b 05 c7 d1 b3 00 4d 85 f6 0f 95
RSP: 0018:ffff888627b437e0 EFLAGS: 00010202
RAX: 0000000000000000 RBX: dead000000000100 RCX: ffff88862279c000
RDX: ffff888614a342c0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888618a88000 R08: 0000000000000001 R09: 00000000000003e8
R10: 0000000000000000 R11: ffff888614a34140 R12: 0000000000000000
R13: 0000000000000062 R14: dead000000000100 R15: ffff888616430000
FS:  0000000000000000(0000) GS:ffff888627b40000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6d2bc6d000 CR3: 000000000200a000 CR4: 00000000000006e0
Call Trace:
 &lt;IRQ&gt;
 __dev_queue_xmit+0x623/0x870
 ? masked_flow_lookup+0xf7/0x220 [openvswitch]
 ? ep_poll_callback+0x101/0x310
 do_execute_actions+0xaba/0xaf0 [openvswitch]
 ? __wake_up_common+0x8a/0x150
 ? __wake_up_common_lock+0x87/0xc0
 ? queue_userspace_packet+0x31c/0x5b0 [openvswitch]
 ovs_execute_actions+0x47/0x120 [openvswitch]
 ovs_dp_process_packet+0x7d/0x110 [openvswitch]
 ovs_vport_receive+0x6e/0xd0 [openvswitch]
 ? dst_alloc+0x64/0x90
 ? rt_dst_alloc+0x50/0xd0
 ? ip_route_input_slow+0x19a/0x9a0
 ? __udp_enqueue_schedule_skb+0x198/0x1b0
 ? __udp4_lib_rcv+0x856/0xa30
 ? __udp4_lib_rcv+0x856/0xa30
 ? cpumask_next_and+0x19/0x20
 ? find_busiest_group+0x12d/0xcd0
 netdev_frame_hook+0xce/0x150 [openvswitch]
 __netif_receive_skb_core+0x205/0xae0
 __netif_receive_skb_list_core+0x11e/0x220
 netif_receive_skb_list+0x203/0x460
 ? __efx_rx_packet+0x335/0x5e0 [sfc]
 efx_poll+0x182/0x320 [sfc]
 net_rx_action+0x294/0x3c0
 __do_softirq+0xca/0x297
 irq_exit+0xa6/0xb0
 do_IRQ+0x54/0xd0
 common_interrupt+0xf/0xf
 &lt;/IRQ&gt;
========
So, in all listified-receive handling, instead pull skbs off the lists with
 skb_list_del_init().

Fixes: 9af86f933894 ("net: core: fix use-after-free in __netif_receive_skb_list_core")
Fixes: 7da517a3bc52 ("net: core: Another step of skb receive list processing")
Fixes: a4ca8b7df73c ("net: ipv4: fix drop handling in ip_list_rcv() and ip_list_rcv_finish()")
Fixes: d8269e2cbf90 ("net: ipv6: listify ipv6_rcv() and ip6_rcv_finish()")
Signed-off-by: Edward Cree &lt;ecree@solarflare.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>packet: copy user buffers before orphan or clone</title>
<updated>2018-12-05T18:31:58Z</updated>
<author>
<name>Willem de Bruijn</name>
<email>willemb@google.com</email>
</author>
<published>2018-11-20T18:00:18Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=f2a67e68dbaeae7c88e5522873d7b908911f9f77'/>
<id>urn:sha1:f2a67e68dbaeae7c88e5522873d7b908911f9f77</id>
<content type='text'>
[ Upstream commit 5cd8d46ea1562be80063f53c7c6a5f40224de623 ]

tpacket_snd sends packets with user pages linked into skb frags. It
notifies that pages can be reused when the skb is released by setting
skb-&gt;destructor to tpacket_destruct_skb.

This can cause data corruption if the skb is orphaned (e.g., on
transmit through veth) or cloned (e.g., on mirror to another psock).

Create a kernel-private copy of data in these cases, same as tun/tap
zerocopy transmission. Reuse that infrastructure: mark the skb as
SKBTX_ZEROCOPY_FRAG, which will trigger copy in skb_orphan_frags(_rx).

Unlike other zerocopy packets, do not set shinfo destructor_arg to
struct ubuf_info. tpacket_destruct_skb already uses that ptr to notify
when the original skb is released and a timestamp is recorded. Do not
change this timestamp behavior. The ubuf_info-&gt;callback is not needed
anyway, as no zerocopy notification is expected.

Mark destructor_arg as not-a-uarg by setting the lower bit to 1. The
resulting value is not a valid ubuf_info pointer, nor a valid
tpacket_snd frame address. Add skb_zcopy_.._nouarg helpers for this.

The fix relies on features introduced in commit 52267790ef52 ("sock:
add MSG_ZEROCOPY"), so can be backported as is only to 4.14.

Tested with from `./in_netns.sh ./txring_overwrite` from
http://github.com/wdebruij/kerneltools/tests

Fixes: 69e3c75f4d54 ("net: TX_RING and packet mmap")
Reported-by: Anand H. Krishnan &lt;anandhkrishnan@gmail.com&gt;
Signed-off-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next</title>
<updated>2018-08-13T17:07:23Z</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2018-08-13T17:07:23Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=c1617fb4c5eea2ad38b5ffb937a732dbb137117f'/>
<id>urn:sha1:c1617fb4c5eea2ad38b5ffb937a732dbb137117f</id>
<content type='text'>
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-08-13

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Add driver XDP support for veth. This can be used in conjunction with
   redirect of another XDP program e.g. sitting on NIC so the xdp_frame
   can be forwarded to the peer veth directly without modification,
   from Toshiaki.

2) Add a new BPF map type REUSEPORT_SOCKARRAY and prog type SK_REUSEPORT
   in order to provide more control and visibility on where a SO_REUSEPORT
   sk should be located, and the latter enables to directly select a sk
   from the bpf map. This also enables map-in-map for application migration
   use cases, from Martin.

3) Add a new BPF helper bpf_skb_ancestor_cgroup_id() that returns the id
   of cgroup v2 that is the ancestor of the cgroup associated with the
   skb at the ancestor_level, from Andrey.

4) Implement BPF fs map pretty-print support based on BTF data for regular
   hash table and LRU map, from Yonghong.

5) Decouple the ability to attach BTF for a map from the key and value
   pretty-printer in BPF fs, and enable further support of BTF for maps for
   percpu and LPM trie, from Daniel.

6) Implement a better BPF sample of using XDP's CPU redirect feature for
   load balancing SKB processing to remote CPU. The sample implements the
   same XDP load balancing as Suricata does which is symmetric hash based
   on IP and L4 protocol, from Jesper.

7) Revert adding NULL pointer check with WARN_ON_ONCE() in __xdp_return()'s
   critical path as it is ensured that the allocator is present, from Björn.
====================

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>net: Export skb_headers_offset_update</title>
<updated>2018-08-10T14:12:20Z</updated>
<author>
<name>Toshiaki Makita</name>
<email>makita.toshiaki@lab.ntt.co.jp</email>
</author>
<published>2018-08-03T07:58:09Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b0768a86585d4d951a30ff565f19598dbbd67897'/>
<id>urn:sha1:b0768a86585d4d951a30ff565f19598dbbd67897</id>
<content type='text'>
This is needed for veth XDP which does skb_copy_expand()-like operation.

v2:
- Drop skb_copy_header part because it has already been exported now.

Signed-off-by: Toshiaki Makita &lt;makita.toshiaki@lab.ntt.co.jp&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
</entry>
<entry>
<title>net: skbuff.h: fix using plain integer as NULL warning</title>
<updated>2018-08-09T21:10:01Z</updated>
<author>
<name>YueHaibing</name>
<email>yuehaibing@huawei.com</email>
</author>
<published>2018-08-08T11:40:31Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=15693fd37fc3a49da356164ed15b571c175efc34'/>
<id>urn:sha1:15693fd37fc3a49da356164ed15b571c175efc34</id>
<content type='text'>
Fixes the following sparse warning:
./include/linux/skbuff.h:2365:58: warning: Using plain integer as NULL pointer

Signed-off-by: YueHaibing &lt;yuehaibing@huawei.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>ip: use rb trees for IP frag queue.</title>
<updated>2018-08-06T00:16:46Z</updated>
<author>
<name>Peter Oskolkov</name>
<email>posk@google.com</email>
</author>
<published>2018-08-02T23:34:39Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=fa0f527358bd900ef92f925878ed6bfbd51305cc'/>
<id>urn:sha1:fa0f527358bd900ef92f925878ed6bfbd51305cc</id>
<content type='text'>
Similar to TCP OOO RX queue, it makes sense to use rb trees to store
IP fragments, so that OOO fragments are inserted faster.

Tested:

- a follow-up patch contains a rather comprehensive ip defrag
  self-test (functional)
- ran neper `udp_stream -c -H &lt;host&gt; -F 100 -l 300 -T 20`:
    netstat --statistics
    Ip:
        282078937 total packets received
        0 forwarded
        0 incoming packets discarded
        946760 incoming packets delivered
        18743456 requests sent out
        101 fragments dropped after timeout
        282077129 reassemblies required
        944952 packets reassembled ok
        262734239 packet reassembles failed
   (The numbers/stats above are somewhat better re:
    reassemblies vs a kernel without this patchset. More
    comprehensive performance testing TBD).

Reported-by: Jann Horn &lt;jannh@google.com&gt;
Reported-by: Juha-Matti Tilli &lt;juha-matti.tilli@iki.fi&gt;
Suggested-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Peter Oskolkov &lt;posk@google.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Florian Westphal &lt;fw@strlen.de&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
</feed>
