]> Gitweb @ Texas Instruments - Open Source Git Repositories - git.TI.com/gitweb - rpmsg/hwspinlock.git/commit
ip6_tunnel: Fix missing tunnel encapsulation limit option
authorCraig Gallek <cgallek@google.com>
Wed, 26 Apr 2017 18:37:45 +0000 (14:37 -0400)
committerDavid S. Miller <davem@davemloft.net>
Mon, 1 May 2017 18:52:45 +0000 (14:52 -0400)
commit89a23c8b528bd2c89f3981573d6cd7d23840c8a6
tree47e6c25d2e0cbc49c80860937ef60bf1a1950c19
parentf9ed236c2aed30eef4b2c8025973631714655301
ip6_tunnel: Fix missing tunnel encapsulation limit option

The IPv6 tunneling code tries to insert IPV6_TLV_TNL_ENCAP_LIMIT and
IPV6_TLV_PADN options when an encapsulation limit is defined (the
default is a limit of 4).  An MTU adjustment is done to account for
these options as well.  However, the options are never present in the
generated packets.

The issue appears to be a subtlety between IPV6_DSTOPTS and
IPV6_RTHDRDSTOPTS defined in RFC 3542.  When the IPIP tunnel driver was
written, the encap limit options were included as IPV6_RTHDRDSTOPTS in
dst0opt of struct ipv6_txoptions.  Later, ipv6_push_nfrags_opts was
(correctly) updated to require IPV6_RTHDR options when IPV6_RTHDRDSTOPTS
are to be used.  This caused the options to no longer be included in v6
encapsulated packets.

The fix is to use IPV6_DSTOPTS (in dst1opt of struct ipv6_txoptions)
instead.  IPV6_DSTOPTS do not have the additional IPV6_RTHDR requirement.

Fixes: 1df64a8569c7: ("[IPV6]: Add ip6ip6 tunnel driver.")
Fixes: 333fad5364d6: ("[IPV6]: Support several new sockopt / ancillary data in Advanced API (RFC3542)")
Signed-off-by: Craig Gallek <kraig@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/ipv6/ip6_tunnel.c