Merge branch 'ip6_gre-Fixes-in-headroom-handling'

Browse source

Petr Machata says:

====================
net: ip6_gre: Fixes in headroom handling

This series mends some problems in headroom management in ip6_gre
module. The current code base has the following three closely-related
problems:

- ip6gretap tunnels neglect to ensure there's enough writable headroom
  before pushing GRE headers.

- ip6erspan does this, but assumes that dev->needed_headroom is primed.
  But that doesn't happen until ip6_tnl_xmit() is called later. Thus for
  the first packet, ip6erspan actually behaves like ip6gretap above.

- ip6erspan shares some of the code with ip6gretap, including
  calculations of needed header length. While there is custom
  ERSPAN-specific code for calculating the headroom, the computed
  values are overwritten by the ip6gretap code.

The first two issues lead to a kernel panic in situations where a packet
is mirrored from a veth device to the device in question. They are
fixed, respectively, in patches #1 and #2, which include the full panic
trace and a reproducer.

The rest of the patchset deals with the last issue. In patches #3 to #6,
several functions are split up into reusable parts. Finally in patch #7
these blocks are used to compose ERSPAN-specific callbacks where
necessary to fix the hlen calculation.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

...

This commit is contained in:

David S. Miller 2018-05-17 16:50:20 -04:00

parent 02f99df187 2d665034f2

commit 374edea4aa

1 changed files with 145 additions and 39 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

214

net/ipv6/ip6_gre.c

View file