[Devel] [PATCH RHEL9 COMMIT] net: udp: use kfree_skb_reason() in udp_queue_rcv_one_skb()

[Konstantin Khorenko]

The commit is pushed to "branch-rh9-5.14.0-162.6.1.vz9.18.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh9-5.14.0-162.6.1.vz9.18.2
------>
commit b02174e5f6fa87521b11b83e14b10764d596a025
Author: Menglong Dong <imagedong at tencent.com>
Date:   Tue Jan 3 17:39:02 2023 +0200

    net: udp: use kfree_skb_reason() in udp_queue_rcv_one_skb()
    
    Replace kfree_skb() with kfree_skb_reason() in udp_queue_rcv_one_skb().
    
    Signed-off-by: Menglong Dong <imagedong at tencent.com>
    Reviewed-by: David Ahern <dsahern at kernel.org>
    Signed-off-by: David S. Miller <davem at davemloft.net>
    Acked-by: Nikolay Borisov <nborisov at suse.com>
    Signed-off-by: Nikolay Borisov <nikolay.borisov at virtuozzo.com>
    
    ======
    Patchset description:
    ms/net: Annotate skb free sites with reason
    
    This series backports most of the patches that add a reason to skb free sites.
    
    https://jira.sw.ru/browse/PSBM-143302
    
    Feature: net: improve verbosity of dropped packets reporting
---
 net/ipv4/udp.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 1c6fe878e635..cf60596d2338 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -2120,14 +2120,17 @@ static int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
  */
 static int udp_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
 {
+	int drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
 	struct udp_sock *up = udp_sk(sk);
 	int is_udplite = IS_UDPLITE(sk);
 
 	/*
 	 *	Charge it to the socket, dropping if the queue is full.
 	 */
-	if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
+	if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) {
+		drop_reason = SKB_DROP_REASON_XFRM_POLICY;
 		goto drop;
+	}
 	nf_reset_ct(skb);
 
 	if (static_branch_unlikely(&udp_encap_needed_key) && up->encap_type) {
@@ -2204,8 +2207,10 @@ static int udp_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
 	    udp_lib_checksum_complete(skb))
 			goto csum_error;
 
-	if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr)))
+	if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) {
+		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
 		goto drop;
+	}
 
 	udp_csum_pull_header(skb);
 
@@ -2213,11 +2218,12 @@ static int udp_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
 	return __udp_queue_rcv_skb(sk, skb);
 
 csum_error:
+	drop_reason = SKB_DROP_REASON_UDP_CSUM;
 	__UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
 drop:
 	__UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
 	atomic_inc(&sk->sk_drops);
-	kfree_skb(skb);
+	kfree_skb_reason(skb, drop_reason);
 	return -1;
 }