[PATCH 5.15 079/201] net: netfilter: use kfree_drop_reason() for NF_DROP

From: Greg Kroah-Hartman
Date: Wed Jul 27 2022 - 13:08:41 EST


From: Menglong Dong <imagedong@xxxxxxxxxxx>

[ Upstream commit 2df3041ba3be950376e8c25a8f6da22f7fcc765c ]

Replace kfree_skb() with kfree_skb_reason() in nf_hook_slow() when
skb is dropped by reason of NF_DROP. Following new drop reasons
are introduced:

SKB_DROP_REASON_NETFILTER_DROP

Signed-off-by: Menglong Dong <imagedong@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
include/linux/skbuff.h | 1 +
include/trace/events/skb.h | 1 +
net/netfilter/core.c | 3 ++-
3 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index f329c617eb96..b63da0d1a4b2 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -317,6 +317,7 @@ enum skb_drop_reason {
SKB_DROP_REASON_TCP_CSUM, /* TCP checksum error */
SKB_DROP_REASON_SOCKET_FILTER, /* dropped by socket filter */
SKB_DROP_REASON_UDP_CSUM, /* UDP checksum error */
+ SKB_DROP_REASON_NETFILTER_DROP, /* dropped by netfilter */
SKB_DROP_REASON_MAX,
};

diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h
index a8a64b97504d..3d89f7b09a43 100644
--- a/include/trace/events/skb.h
+++ b/include/trace/events/skb.h
@@ -16,6 +16,7 @@
EM(SKB_DROP_REASON_TCP_CSUM, TCP_CSUM) \
EM(SKB_DROP_REASON_SOCKET_FILTER, SOCKET_FILTER) \
EM(SKB_DROP_REASON_UDP_CSUM, UDP_CSUM) \
+ EM(SKB_DROP_REASON_NETFILTER_DROP, NETFILTER_DROP) \
EMe(SKB_DROP_REASON_MAX, MAX)

#undef EM
diff --git a/net/netfilter/core.c b/net/netfilter/core.c
index 60332fdb6dd4..cca0762a9010 100644
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@ -592,7 +592,8 @@ int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state,
case NF_ACCEPT:
break;
case NF_DROP:
- kfree_skb(skb);
+ kfree_skb_reason(skb,
+ SKB_DROP_REASON_NETFILTER_DROP);
ret = NF_DROP_GETERR(verdict);
if (ret == 0)
ret = -EPERM;
--
2.35.1