linux/net/openvswitch
Ilya Maximets 1926407a4a net: openvswitch: fix uAPI incompatibility with existing user space
Few years ago OVS user space made a strange choice in the commit [1]
to define types only valid for the user space inside the copy of a
kernel uAPI header.  '#ifndef __KERNEL__' and another attribute was
added later.

This leads to the inevitable clash between user space and kernel types
when the kernel uAPI is extended.  The issue was unveiled with the
addition of a new type for IPv6 extension header in kernel uAPI.

When kernel provides the OVS_KEY_ATTR_IPV6_EXTHDRS attribute to the
older user space application, application tries to parse it as
OVS_KEY_ATTR_PACKET_TYPE and discards the whole netlink message as
malformed.  Since OVS_KEY_ATTR_IPV6_EXTHDRS is supplied along with
every IPv6 packet that goes to the user space, IPv6 support is fully
broken.

Fixing that by bringing these user space attributes to the kernel
uAPI to avoid the clash.  Strictly speaking this is not the problem
of the kernel uAPI, but changing it is the only way to avoid breakage
of the older user space applications at this point.

These 2 types are explicitly rejected now since they should not be
passed to the kernel.  Additionally, OVS_KEY_ATTR_TUNNEL_INFO moved
out from the '#ifdef __KERNEL__' as there is no good reason to hide
it from the userspace.  And it's also explicitly rejected now, because
it's for in-kernel use only.

Comments with warnings were added to avoid the problem coming back.

(1 << type) converted to (1ULL << type) to avoid integer overflow on
OVS_KEY_ATTR_IPV6_EXTHDRS, since it equals 32 now.

 [1] beb75a40fdc2 ("userspace: Switching of L3 packets in L2 pipeline")

Fixes: 28a3f06017 ("net: openvswitch: IPv6: Add IPv6 extension header support")
Link: https://lore.kernel.org/netdev/3adf00c7-fe65-3ef4-b6d7-6d8a0cad8a5f@nvidia.com
Link: beb75a40fd
Reported-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Aaron Conole <aconole@redhat.com>
Link: https://lore.kernel.org/r/20220309222033.3018976-1-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-10 20:14:52 -08:00
..
actions.c openvswitch: Fix setting ipv6 fields causing hw csum failure 2022-02-24 09:16:21 -08:00
conntrack.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2022-01-09 15:59:23 -08:00
conntrack.h net/sched: act_api: fix miss set post_ct for ovs after do conntrack in act_ct 2021-03-16 15:22:18 -07:00
datapath.c net/sched: Enable tc skb ext allocation on chain miss only when needed 2022-02-05 10:12:53 +00:00
datapath.h net/sched: Enable tc skb ext allocation on chain miss only when needed 2022-02-05 10:12:53 +00:00
dp_notify.c
flow_netlink.c net: openvswitch: fix uAPI incompatibility with existing user space 2022-03-10 20:14:52 -08:00
flow_netlink.h
flow_table.c openvswitch: Optimize operation for key comparison 2021-07-01 11:13:10 -07:00
flow_table.h net: openvswitch: fix to make sure flow_lookup() is not preempted 2020-10-18 12:29:36 -07:00
flow.c net: openvswitch: remove unneeded semicolon 2022-03-02 22:22:18 -08:00
flow.h net: openvswitch: IPv6: Add IPv6 extension header support 2022-02-25 10:32:55 +00:00
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile openvswitch: add trace points 2021-06-22 10:47:32 -07:00
meter.c include/linux/mm.h: move nr_free_buffer_pages from swap.h to mm.h 2021-11-06 13:30:43 -07:00
meter.h net: openvswitch: use u64 for meter bucket 2020-04-23 18:26:11 -07:00
openvswitch_trace.c openvswitch: add trace points 2021-06-22 10:47:32 -07:00
openvswitch_trace.h openvswitch: add trace points 2021-06-22 10:47:32 -07:00
vport-geneve.c
vport-gre.c
vport-internal_dev.c net: openvswitch: use core API to update/provide stats 2020-11-14 16:59:32 -08:00
vport-internal_dev.h
vport-netdev.c openvswitch: add net device refcount tracker to struct vport 2021-12-07 20:45:00 -08:00
vport-netdev.h
vport-vxlan.c
vport.c net: Add skb_clear_tstamp() to keep the mono delivery_time 2022-03-03 14:38:48 +00:00
vport.h openvswitch: add net device refcount tracker to struct vport 2021-12-07 20:45:00 -08:00