[PATCH stable 0/3] SOF_TIMESTAMPING_OPT_ID backport to 4.14 and 4.19

[Vladimir Oltean]

As discussed with Willem here:
https://lore.kernel.org/netdev/CA+FuTSdQ57O6RWj_Lenmu_Vd3NEX9xMzMYkB0C3rKMzGgcPc6A@xxxxxxxxxxxxxx/T/

the kernel silently doesn't act upon the SOF_TIMESTAMPING_OPT_ID socket
option in several cases on older kernels, yet user space has no way to
find out about this, practically resulting in broken functionality.

This patch set backports the support towards linux-4.14.y and linux-4.19.y,
which fixes the issue described above by simply making the kernel act
upon SOF_TIMESTAMPING_OPT_ID as expected.

Testing was done with the most recent (not the vintage-correct one)
kselftest script at:
tools/testing/selftests/networking/timestamping/txtimestamp.sh
with the message "OK. All tests passed".

I tried to backport the changes to linux-4.9.y as well, but something
apparently unrelated is broken there, and I didn't investigate further
so I'm not targeting that stable branch:

./txtimestamp.sh
protocol:     TCP
payload:      10
server port:  9000

family:       INET
test SND
    USR: 1581090724 s 856088 us (seq=0, len=0)
./txtimestamp: poll

Willem de Bruijn (2):
  ipv6: add missing tx timestamping on IPPROTO_RAW
  net: add missing SOF_TIMESTAMPING_OPT_ID support

 include/net/sock.h     | 25 +++++++++++++++++++++----
 net/can/raw.c          |  2 +-
 net/ipv4/raw.c         |  2 +-
 net/ipv6/raw.c         |  7 +++++--
 net/packet/af_packet.c |  6 +++---
 5 files changed, 31 insertions(+), 11 deletions(-)

-- 
2.25.1