[PATCH net-next v7 0/4] Add support for SO_PRIORITY cmsg

[Anna Emese Nyiri <annaemesenyiri@gmail.com>]

Introduce a new helper function, `sk_set_prio_allowed`,
to centralize the logic for validating priority settings.
Add support for the `SO_PRIORITY` control message,
enabling user-space applications to set socket priority
via control messages (cmsg).

Patch Overview:

Patch 1/4: Introduce 'sk_set_prio_allowed' helper function.
Patch 2/4: Add support for setting SO_PRIORITY via control messages
Patch 3/4: Add test for SO_PRIORITY setting via control messages
Patch 4/4: Add new socket option, SO_RCVPRIORITY

v7:

- Carry Eric's and Willem's "Reviewed-by" tags from v3 to
  patch 1/4 since that is resubmitted without changes.
- Carry Willem's "Reviewed-by" tag from v4 in patch 2/4,
  as it is resubmitted without changes.
- Carry Willem's "Reviewed-by" tag from v5 in patch 4/4,
  as it is resubmitted without changes.
- Carry Willem's "Reviewed-by" tag from v6
  since it is resubmitted with minor cosmetic changes in
  patch 3/4.
- Carry Willem's "Acked-by" tag from v5 on FILTER_COUNTER
  (patch 3/4).
- Carry Ido's "Reviewed-by" and "Tested-by" tags from v6
  since it is resubmitted with minor cosmetic changes in
  patch 3/4.
- Align the code to the open parenthesis in cmsg_sender.c
  (patch 3/4).
- Remove unnecessary blank line in cmsg_so_priority.sh
  (patch 3/4).
- Remove unused delay variable from cmsg_so_priority.sh 
  (patch 3/4).
- Rebased on net-next.

v6:

https://lore.kernel.org/netdev/20241210191309.8681-1-annaemesenyiri@gmail.com/
- Carry Eric's and Willem's "Reviewed-by" tags from v3 to
  patch 1/4 since that is resubmitted without changes.
- Carry Willem's "Reviewed-by" tag from v4 in patch 2/4,
  as it is resubmitted without changes.
- Carry Willem's "Reviewed-by" tag from v5 in patch 4/4,
  as it is resubmitted without changes.
- Use KSFT_SKIP in jq installation test and
  add 'nodad' flag for IPv6 address in cmsg_so_priority.sh (patch 3/4).
- Rebased on net-next.

v5:

https://lore.kernel.org/netdev/20241205133112.17903-1-annaemesenyiri@gmail.com/

- Carry Eric's and Willem's "Reviewed-by" tags from v3 to
  patch 1/4 since that is resubmitted without changes.
- Carry Willem's "Reviewed-by" tag from v4 in patch 2/4,
  as it is resubmitted without changes.
- Eliminate variable duplication, fix indentation, simplify cleanup,
  verify dependencies, separate setsockopt and control message 
  priority testing, and modify namespace setup 
  in patch 3/4 cmsg_so_priority.sh.
- Add cmsg_so_priority.sh to tools/testing/selftests/net/Makefile.
- Remove the unused variable, rename priority_cmsg to priority,
  and document the -P option in cmsg_sender.c in patch 3/4.
- New in v5: add new socket option, SO_RCVPRIORITY in patch 4/4.
- Rebased on net-next.

v4:

https://lore.kernel.org/netdev/20241118145147.56236-1-annaemesenyiri@gmail.com/
- Carry Eric's and Willem's "Reviewed-by" tags from v3 to 
  patch 1/3 since that is resubmitted without changes.
- Updated description in patch 2/3.
- Missing ipc6.sockc.priority field added in ping_v6_sendmsg()
  in patch 2/3.
- Update cmsg_so_priority.sh to test SO_PRIORITY sockopt and cmsg
  setting with VLAN priority tagging in patch 3/3. (Ido Schimmel) 
- Rebased on net-next.

v3:

https://lore.kernel.org/netdev/20241107132231.9271-1-annaemesenyiri@gmail.com/
- Updated cover letter text.
- Removed priority field from ipcm_cookie.
- Removed cork->tos value check from ip_setup_cork, so
  cork->priority will now take its value from ipc->sockc.priority.
- Replaced ipc->priority with ipc->sockc.priority
  in ip_cmsg_send().
- Modified the error handling for the SO_PRIORITY
  case in __sock_cmsg_send().
- Added missing initialization for ipc6.sockc.priority.
- Introduced cmsg_so_priority.sh test script.
- Modified cmsg_sender.c to set priority via control message (cmsg).
- Rebased on net-next.


v2:

https://lore.kernel.org/netdev/20241102125136.5030-1-annaemesenyiri@gmail.com/
- Introduced sk_set_prio_allowed helper to check capability
  for setting priority.
- Removed new fields and changed sockcm_cookie::priority
  from char to u32 to align with sk_buff::priority.
- Moved the cork->tos value check for priority setting
  from __ip_make_skb() to ip_setup_cork().
- Rebased on net-next.

v1:

https://lore.kernel.org/all/20241029144142.31382-1-annaemesenyiri@gmail.com/

Anna Emese Nyiri (4):
  Introduce sk_set_prio_allowed helper function
  support SO_PRIORITY cmsg
  test SO_PRIORITY ancillary data with cmsg_sender
  introduce SO_RCVPRIORITY socket option

 arch/alpha/include/uapi/asm/socket.h          |   2 +
 arch/mips/include/uapi/asm/socket.h           |   2 +
 arch/parisc/include/uapi/asm/socket.h         |   2 +
 arch/sparc/include/uapi/asm/socket.h          |   2 +
 include/net/inet_sock.h                       |   2 +-
 include/net/ip.h                              |   2 +-
 include/net/sock.h                            |   8 +-
 include/uapi/asm-generic/socket.h             |   2 +
 net/can/raw.c                                 |   2 +-
 net/core/sock.c                               |  26 ++-
 net/ipv4/ip_output.c                          |   4 +-
 net/ipv4/ip_sockglue.c                        |   2 +-
 net/ipv4/raw.c                                |   2 +-
 net/ipv6/ip6_output.c                         |   3 +-
 net/ipv6/ping.c                               |   1 +
 net/ipv6/raw.c                                |   3 +-
 net/ipv6/udp.c                                |   1 +
 net/packet/af_packet.c                        |   2 +-
 net/socket.c                                  |  11 ++
 tools/include/uapi/asm-generic/socket.h       |   2 +
 tools/testing/selftests/net/Makefile          |   1 +
 tools/testing/selftests/net/cmsg_sender.c     |  11 +-
 .../testing/selftests/net/cmsg_so_priority.sh | 151 ++++++++++++++++++
 23 files changed, 228 insertions(+), 16 deletions(-)
 create mode 100755 tools/testing/selftests/net/cmsg_so_priority.sh

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2.43.0