[net-next,v2,0/3] net: icmp: add skb drop reasons to icmp

Message

Menglong Dong March 16, 2022, 2:46 a.m. UTC

From: Menglong Dong <[e-mail]>

In the commit c504e5c2f964 ("net: skb: introduce kfree_skb_reason()"),
we added the support of reporting the reasons of skb drops to kfree_skb
tracepoint. And in this series patches, reasons for skb drops are added
to ICMP protocol.

In order to report the reasons of skb drops in 'sock_queue_rcv_skb()',
the function 'sock_queue_rcv_skb_reason()' is introduced in the 1th
patch, which is used in the 2th patch.

In the 2th patch, we introduce the new function __ping_queue_rcv_skb()
to report drop reasons by its return value.

In the 3th patch, we make ICMP message handler functions return drop
reasons, which means we change the return type of 'handler()' in
'struct icmp_control' from 'bool' to 'enum skb_drop_reason'. This
changed its original intention, as 'false' means failure, but
'SKB_NOT_DROPPED_YET', which is 0, means success now. Therefore, we
have to change all usages of these handler. Following "handler" functions
are involved:

icmp_unreach()
icmp_redirect()
icmp_echo()
icmp_timestamp()
icmp_discard()

And following drop reasons are added(what they mean can be see
in the document for them):

SKB_DROP_REASON_ICMP_CSUM
SKB_DROP_REASON_ICMP_TYPE
SKB_DROP_REASON_ICMP_BROADCAST

Changes since v1:
- introduce __ping_queue_rcv_skb() instead of change the return value
  of ping_queue_rcv_skb() in the 2th patch, as Paolo suggested

Menglong Dong (3):
  net: sock: introduce sock_queue_rcv_skb_reason()
  net: icmp: introduce __ping_queue_rcv_skb() to report drop reasons
  net: icmp: add reasons of the skb drops to icmp protocol

 include/linux/skbuff.h     |  5 +++
 include/net/ping.h         |  2 +-
 include/net/sock.h         |  9 ++++-
 include/trace/events/skb.h |  3 ++
 net/core/sock.c            | 30 ++++++++++++---
 net/ipv4/icmp.c            | 75 ++++++++++++++++++++++----------------
 net/ipv4/ping.c            | 32 ++++++++++------
 net/ipv6/icmp.c            | 24 +++++++-----
 8 files changed, 121 insertions(+), 59 deletions(-)