net: skb: use kfree_skb_reason() in __udp4_lib_rcv()
authorMenglong Dong <imagedong@tencent.com>
Sun, 9 Jan 2022 06:36:28 +0000 (14:36 +0800)
committerJakub Kicinski <kuba@kernel.org>
Mon, 10 Jan 2022 00:30:35 +0000 (16:30 -0800)
Replace kfree_skb() with kfree_skb_reason() in __udp4_lib_rcv.
New drop reason 'SKB_DROP_REASON_UDP_CSUM' is added for udp csum
error.

Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
include/linux/skbuff.h
include/trace/events/skb.h
net/ipv4/udp.c

index c9c97b0..af64c7d 100644 (file)
@@ -317,6 +317,7 @@ enum skb_drop_reason {
        SKB_DROP_REASON_PKT_TOO_SMALL,
        SKB_DROP_REASON_TCP_CSUM,
        SKB_DROP_REASON_TCP_FILTER,
+       SKB_DROP_REASON_UDP_CSUM,
        SKB_DROP_REASON_MAX,
 };
 
index faa7d06..3e042ca 100644 (file)
@@ -15,6 +15,7 @@
        EM(SKB_DROP_REASON_PKT_TOO_SMALL, PKT_TOO_SMALL)        \
        EM(SKB_DROP_REASON_TCP_CSUM, TCP_CSUM)                  \
        EM(SKB_DROP_REASON_TCP_FILTER, TCP_FILTER)              \
+       EM(SKB_DROP_REASON_UDP_CSUM, UDP_CSUM)                  \
        EMe(SKB_DROP_REASON_MAX, MAX)
 
 #undef EM
index c2a4411..464590e 100644 (file)
@@ -2411,6 +2411,9 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
        __be32 saddr, daddr;
        struct net *net = dev_net(skb->dev);
        bool refcounted;
+       int drop_reason;
+
+       drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
 
        /*
         *  Validate the packet.
@@ -2466,6 +2469,7 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
        if (udp_lib_checksum_complete(skb))
                goto csum_error;
 
+       drop_reason = SKB_DROP_REASON_NO_SOCKET;
        __UDP_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
        icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
 
@@ -2473,10 +2477,11 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
         * Hmm.  We got an UDP packet to a port to which we
         * don't wanna listen.  Ignore it.
         */
-       kfree_skb(skb);
+       kfree_skb_reason(skb, drop_reason);
        return 0;
 
 short_packet:
+       drop_reason = SKB_DROP_REASON_PKT_TOO_SMALL;
        net_dbg_ratelimited("UDP%s: short packet: From %pI4:%u %d/%d to %pI4:%u\n",
                            proto == IPPROTO_UDPLITE ? "Lite" : "",
                            &saddr, ntohs(uh->source),
@@ -2489,6 +2494,7 @@ csum_error:
         * RFC1122: OK.  Discards the bad packet silently (as far as
         * the network is concerned, anyway) as per 4.1.3.4 (MUST).
         */
+       drop_reason = SKB_DROP_REASON_UDP_CSUM;
        net_dbg_ratelimited("UDP%s: bad checksum. From %pI4:%u to %pI4:%u ulen %d\n",
                            proto == IPPROTO_UDPLITE ? "Lite" : "",
                            &saddr, ntohs(uh->source), &daddr, ntohs(uh->dest),
@@ -2496,7 +2502,7 @@ csum_error:
        __UDP_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
 drop:
        __UDP_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
-       kfree_skb(skb);
+       kfree_skb_reason(skb, drop_reason);
        return 0;
 }