new file mode 100644
@@ -0,0 +1,312 @@
+#ifndef __BACKPORT_DROPREASON_H
+#define __BACKPORT_DROPREASON_H
+
+#if LINUX_VERSION_IS_LESS(6,4,0)
+/**
+ * enum skb_drop_reason_subsys - subsystem tag for (extended) drop reasons
+ */
+enum skb_drop_reason_subsys {
+ /** @SKB_DROP_REASON_SUBSYS_CORE: core drop reasons defined above */
+ SKB_DROP_REASON_SUBSYS_CORE,
+
+ /**
+ * @SKB_DROP_REASON_SUBSYS_MAC80211_UNUSABLE: mac80211 drop reasons
+ * for unusable frames, see net/mac80211/drop.h
+ */
+ SKB_DROP_REASON_SUBSYS_MAC80211_UNUSABLE,
+
+ /**
+ * @SKB_DROP_REASON_SUBSYS_MAC80211_MONITOR: mac80211 drop reasons
+ * for frames still going to monitor, see net/mac80211/drop.h
+ */
+ SKB_DROP_REASON_SUBSYS_MAC80211_MONITOR,
+
+ /** @SKB_DROP_REASON_SUBSYS_NUM: number of subsystems defined */
+ SKB_DROP_REASON_SUBSYS_NUM
+};
+
+struct drop_reason_list {
+ const char * const *reasons;
+ size_t n_reasons;
+};
+
+/**
+ * enum skb_drop_reason - the reasons of skb drops
+ *
+ * The reason of skb drop, which is used in kfree_skb_reason().
+ */
+enum skb_drop_reason {
+ /**
+ * @SKB_NOT_DROPPED_YET: skb is not dropped yet (used for no-drop case)
+ */
+ SKB_NOT_DROPPED_YET = 0,
+ /** @SKB_CONSUMED: packet has been consumed */
+ SKB_CONSUMED,
+ /** @SKB_DROP_REASON_NOT_SPECIFIED: drop reason is not specified */
+ SKB_DROP_REASON_NOT_SPECIFIED,
+ /** @SKB_DROP_REASON_NO_SOCKET: socket not found */
+ SKB_DROP_REASON_NO_SOCKET,
+ /** @SKB_DROP_REASON_PKT_TOO_SMALL: packet size is too small */
+ SKB_DROP_REASON_PKT_TOO_SMALL,
+ /** @SKB_DROP_REASON_TCP_CSUM: TCP checksum error */
+ SKB_DROP_REASON_TCP_CSUM,
+ /** @SKB_DROP_REASON_SOCKET_FILTER: dropped by socket filter */
+ SKB_DROP_REASON_SOCKET_FILTER,
+ /** @SKB_DROP_REASON_UDP_CSUM: UDP checksum error */
+ SKB_DROP_REASON_UDP_CSUM,
+ /** @SKB_DROP_REASON_NETFILTER_DROP: dropped by netfilter */
+ SKB_DROP_REASON_NETFILTER_DROP,
+ /**
+ * @SKB_DROP_REASON_OTHERHOST: packet don't belong to current host
+ * (interface is in promisc mode)
+ */
+ SKB_DROP_REASON_OTHERHOST,
+ /** @SKB_DROP_REASON_IP_CSUM: IP checksum error */
+ SKB_DROP_REASON_IP_CSUM,
+ /**
+ * @SKB_DROP_REASON_IP_INHDR: there is something wrong with IP header (see
+ * IPSTATS_MIB_INHDRERRORS)
+ */
+ SKB_DROP_REASON_IP_INHDR,
+ /**
+ * @SKB_DROP_REASON_IP_RPFILTER: IP rpfilter validate failed. see the
+ * document for rp_filter in ip-sysctl.rst for more information
+ */
+ SKB_DROP_REASON_IP_RPFILTER,
+ /**
+ * @SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST: destination address of L2 is
+ * multicast, but L3 is unicast.
+ */
+ SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST,
+ /** @SKB_DROP_REASON_XFRM_POLICY: xfrm policy check failed */
+ SKB_DROP_REASON_XFRM_POLICY,
+ /** @SKB_DROP_REASON_IP_NOPROTO: no support for IP protocol */
+ SKB_DROP_REASON_IP_NOPROTO,
+ /** @SKB_DROP_REASON_SOCKET_RCVBUFF: socket receive buff is full */
+ SKB_DROP_REASON_SOCKET_RCVBUFF,
+ /**
+ * @SKB_DROP_REASON_PROTO_MEM: proto memory limition, such as udp packet
+ * drop out of udp_memory_allocated.
+ */
+ SKB_DROP_REASON_PROTO_MEM,
+ /**
+ * @SKB_DROP_REASON_TCP_MD5NOTFOUND: no MD5 hash and one expected,
+ * corresponding to LINUX_MIB_TCPMD5NOTFOUND
+ */
+ SKB_DROP_REASON_TCP_MD5NOTFOUND,
+ /**
+ * @SKB_DROP_REASON_TCP_MD5UNEXPECTED: MD5 hash and we're not expecting
+ * one, corresponding to LINUX_MIB_TCPMD5UNEXPECTED
+ */
+ SKB_DROP_REASON_TCP_MD5UNEXPECTED,
+ /**
+ * @SKB_DROP_REASON_TCP_MD5FAILURE: MD5 hash and its wrong, corresponding
+ * to LINUX_MIB_TCPMD5FAILURE
+ */
+ SKB_DROP_REASON_TCP_MD5FAILURE,
+ /**
+ * @SKB_DROP_REASON_SOCKET_BACKLOG: failed to add skb to socket backlog (
+ * see LINUX_MIB_TCPBACKLOGDROP)
+ */
+ SKB_DROP_REASON_SOCKET_BACKLOG,
+ /** @SKB_DROP_REASON_TCP_FLAGS: TCP flags invalid */
+ SKB_DROP_REASON_TCP_FLAGS,
+ /**
+ * @SKB_DROP_REASON_TCP_ZEROWINDOW: TCP receive window size is zero,
+ * see LINUX_MIB_TCPZEROWINDOWDROP
+ */
+ SKB_DROP_REASON_TCP_ZEROWINDOW,
+ /**
+ * @SKB_DROP_REASON_TCP_OLD_DATA: the TCP data reveived is already
+ * received before (spurious retrans may happened), see
+ * LINUX_MIB_DELAYEDACKLOST
+ */
+ SKB_DROP_REASON_TCP_OLD_DATA,
+ /**
+ * @SKB_DROP_REASON_TCP_OVERWINDOW: the TCP data is out of window,
+ * the seq of the first byte exceed the right edges of receive
+ * window
+ */
+ SKB_DROP_REASON_TCP_OVERWINDOW,
+ /**
+ * @SKB_DROP_REASON_TCP_OFOMERGE: the data of skb is already in the ofo
+ * queue, corresponding to LINUX_MIB_TCPOFOMERGE
+ */
+ SKB_DROP_REASON_TCP_OFOMERGE,
+ /**
+ * @SKB_DROP_REASON_TCP_RFC7323_PAWS: PAWS check, corresponding to
+ * LINUX_MIB_PAWSESTABREJECTED
+ */
+ SKB_DROP_REASON_TCP_RFC7323_PAWS,
+ /** @SKB_DROP_REASON_TCP_INVALID_SEQUENCE: Not acceptable SEQ field */
+ SKB_DROP_REASON_TCP_INVALID_SEQUENCE,
+ /** @SKB_DROP_REASON_TCP_RESET: Invalid RST packet */
+ SKB_DROP_REASON_TCP_RESET,
+ /**
+ * @SKB_DROP_REASON_TCP_INVALID_SYN: Incoming packet has unexpected
+ * SYN flag
+ */
+ SKB_DROP_REASON_TCP_INVALID_SYN,
+ /** @SKB_DROP_REASON_TCP_CLOSE: TCP socket in CLOSE state */
+ SKB_DROP_REASON_TCP_CLOSE,
+ /** @SKB_DROP_REASON_TCP_FASTOPEN: dropped by FASTOPEN request socket */
+ SKB_DROP_REASON_TCP_FASTOPEN,
+ /** @SKB_DROP_REASON_TCP_OLD_ACK: TCP ACK is old, but in window */
+ SKB_DROP_REASON_TCP_OLD_ACK,
+ /** @SKB_DROP_REASON_TCP_TOO_OLD_ACK: TCP ACK is too old */
+ SKB_DROP_REASON_TCP_TOO_OLD_ACK,
+ /**
+ * @SKB_DROP_REASON_TCP_ACK_UNSENT_DATA: TCP ACK for data we haven't
+ * sent yet
+ */
+ SKB_DROP_REASON_TCP_ACK_UNSENT_DATA,
+ /** @SKB_DROP_REASON_TCP_OFO_QUEUE_PRUNE: pruned from TCP OFO queue */
+ SKB_DROP_REASON_TCP_OFO_QUEUE_PRUNE,
+ /** @SKB_DROP_REASON_TCP_OFO_DROP: data already in receive queue */
+ SKB_DROP_REASON_TCP_OFO_DROP,
+ /** @SKB_DROP_REASON_IP_OUTNOROUTES: route lookup failed */
+ SKB_DROP_REASON_IP_OUTNOROUTES,
+ /**
+ * @SKB_DROP_REASON_BPF_CGROUP_EGRESS: dropped by BPF_PROG_TYPE_CGROUP_SKB
+ * eBPF program
+ */
+ SKB_DROP_REASON_BPF_CGROUP_EGRESS,
+ /** @SKB_DROP_REASON_IPV6DISABLED: IPv6 is disabled on the device */
+ SKB_DROP_REASON_IPV6DISABLED,
+ /** @SKB_DROP_REASON_NEIGH_CREATEFAIL: failed to create neigh entry */
+ SKB_DROP_REASON_NEIGH_CREATEFAIL,
+ /** @SKB_DROP_REASON_NEIGH_FAILED: neigh entry in failed state */
+ SKB_DROP_REASON_NEIGH_FAILED,
+ /** @SKB_DROP_REASON_NEIGH_QUEUEFULL: arp_queue for neigh entry is full */
+ SKB_DROP_REASON_NEIGH_QUEUEFULL,
+ /** @SKB_DROP_REASON_NEIGH_DEAD: neigh entry is dead */
+ SKB_DROP_REASON_NEIGH_DEAD,
+ /** @SKB_DROP_REASON_TC_EGRESS: dropped in TC egress HOOK */
+ SKB_DROP_REASON_TC_EGRESS,
+ /**
+ * @SKB_DROP_REASON_QDISC_DROP: dropped by qdisc when packet outputting (
+ * failed to enqueue to current qdisc)
+ */
+ SKB_DROP_REASON_QDISC_DROP,
+ /**
+ * @SKB_DROP_REASON_CPU_BACKLOG: failed to enqueue the skb to the per CPU
+ * backlog queue. This can be caused by backlog queue full (see
+ * netdev_max_backlog in net.rst) or RPS flow limit
+ */
+ SKB_DROP_REASON_CPU_BACKLOG,
+ /** @SKB_DROP_REASON_XDP: dropped by XDP in input path */
+ SKB_DROP_REASON_XDP,
+ /** @SKB_DROP_REASON_TC_INGRESS: dropped in TC ingress HOOK */
+ SKB_DROP_REASON_TC_INGRESS,
+ /** @SKB_DROP_REASON_UNHANDLED_PROTO: protocol not implemented or not supported */
+ SKB_DROP_REASON_UNHANDLED_PROTO,
+ /** @SKB_DROP_REASON_SKB_CSUM: sk_buff checksum computation error */
+ SKB_DROP_REASON_SKB_CSUM,
+ /** @SKB_DROP_REASON_SKB_GSO_SEG: gso segmentation error */
+ SKB_DROP_REASON_SKB_GSO_SEG,
+ /**
+ * @SKB_DROP_REASON_SKB_UCOPY_FAULT: failed to copy data from user space,
+ * e.g., via zerocopy_sg_from_iter() or skb_orphan_frags_rx()
+ */
+ SKB_DROP_REASON_SKB_UCOPY_FAULT,
+ /** @SKB_DROP_REASON_DEV_HDR: device driver specific header/metadata is invalid */
+ SKB_DROP_REASON_DEV_HDR,
+ /**
+ * @SKB_DROP_REASON_DEV_READY: the device is not ready to xmit/recv due to
+ * any of its data structure that is not up/ready/initialized,
+ * e.g., the IFF_UP is not set, or driver specific tun->tfiles[txq]
+ * is not initialized
+ */
+ SKB_DROP_REASON_DEV_READY,
+ /** @SKB_DROP_REASON_FULL_RING: ring buffer is full */
+ SKB_DROP_REASON_FULL_RING,
+ /** @SKB_DROP_REASON_NOMEM: error due to OOM */
+ SKB_DROP_REASON_NOMEM,
+ /**
+ * @SKB_DROP_REASON_HDR_TRUNC: failed to trunc/extract the header from
+ * networking data, e.g., failed to pull the protocol header from
+ * frags via pskb_may_pull()
+ */
+ SKB_DROP_REASON_HDR_TRUNC,
+ /**
+ * @SKB_DROP_REASON_TAP_FILTER: dropped by (ebpf) filter directly attached
+ * to tun/tap, e.g., via TUNSETFILTEREBPF
+ */
+ SKB_DROP_REASON_TAP_FILTER,
+ /**
+ * @SKB_DROP_REASON_TAP_TXFILTER: dropped by tx filter implemented at
+ * tun/tap, e.g., check_filter()
+ */
+ SKB_DROP_REASON_TAP_TXFILTER,
+ /** @SKB_DROP_REASON_ICMP_CSUM: ICMP checksum error */
+ SKB_DROP_REASON_ICMP_CSUM,
+ /**
+ * @SKB_DROP_REASON_INVALID_PROTO: the packet doesn't follow RFC 2211,
+ * such as a broadcasts ICMP_TIMESTAMP
+ */
+ SKB_DROP_REASON_INVALID_PROTO,
+ /**
+ * @SKB_DROP_REASON_IP_INADDRERRORS: host unreachable, corresponding to
+ * IPSTATS_MIB_INADDRERRORS
+ */
+ SKB_DROP_REASON_IP_INADDRERRORS,
+ /**
+ * @SKB_DROP_REASON_IP_INNOROUTES: network unreachable, corresponding to
+ * IPSTATS_MIB_INADDRERRORS
+ */
+ SKB_DROP_REASON_IP_INNOROUTES,
+ /**
+ * @SKB_DROP_REASON_PKT_TOO_BIG: packet size is too big (maybe exceed the
+ * MTU)
+ */
+ SKB_DROP_REASON_PKT_TOO_BIG,
+ /** @SKB_DROP_REASON_DUP_FRAG: duplicate fragment */
+ SKB_DROP_REASON_DUP_FRAG,
+ /** @SKB_DROP_REASON_FRAG_REASM_TIMEOUT: fragment reassembly timeout */
+ SKB_DROP_REASON_FRAG_REASM_TIMEOUT,
+ /**
+ * @SKB_DROP_REASON_FRAG_TOO_FAR: ipv4 fragment too far.
+ * (/proc/sys/net/ipv4/ipfrag_max_dist)
+ */
+ SKB_DROP_REASON_FRAG_TOO_FAR,
+ /**
+ * @SKB_DROP_REASON_TCP_MINTTL: ipv4 ttl or ipv6 hoplimit below
+ * the threshold (IP_MINTTL or IPV6_MINHOPCOUNT).
+ */
+ SKB_DROP_REASON_TCP_MINTTL,
+ /** @SKB_DROP_REASON_IPV6_BAD_EXTHDR: Bad IPv6 extension header. */
+ SKB_DROP_REASON_IPV6_BAD_EXTHDR,
+ /** @SKB_DROP_REASON_IPV6_NDISC_FRAG: invalid frag (suppress_frag_ndisc). */
+ SKB_DROP_REASON_IPV6_NDISC_FRAG,
+ /** @SKB_DROP_REASON_IPV6_NDISC_HOP_LIMIT: invalid hop limit. */
+ SKB_DROP_REASON_IPV6_NDISC_HOP_LIMIT,
+ /** @SKB_DROP_REASON_IPV6_NDISC_BAD_CODE: invalid NDISC icmp6 code. */
+ SKB_DROP_REASON_IPV6_NDISC_BAD_CODE,
+ /** @SKB_DROP_REASON_IPV6_NDISC_BAD_OPTIONS: invalid NDISC options. */
+ SKB_DROP_REASON_IPV6_NDISC_BAD_OPTIONS,
+ /**
+ * @SKB_DROP_REASON_IPV6_NDISC_NS_OTHERHOST: NEIGHBOUR SOLICITATION
+ * for another host.
+ */
+ SKB_DROP_REASON_IPV6_NDISC_NS_OTHERHOST,
+ /**
+ * @SKB_DROP_REASON_MAX: the maximum of core drop reasons, which
+ * shouldn't be used as a real 'reason' - only for tracing code gen
+ */
+ SKB_DROP_REASON_MAX,
+
+ /**
+ * @SKB_DROP_REASON_SUBSYS_MASK: subsystem mask in drop reasons,
+ * see &enum skb_drop_reason_subsys
+ */
+ SKB_DROP_REASON_SUBSYS_MASK = 0xffff0000,
+};
+
+#define SKB_DROP_REASON_SUBSYS_SHIFT 16
+
+void drop_reasons_register_subsys(enum skb_drop_reason_subsys subsys,
+ const struct drop_reason_list *list);
+void drop_reasons_unregister_subsys(enum skb_drop_reason_subsys subsys);
+#endif
+#endif
+
@@ -1,5 +1,9 @@
// SPDX-License-Identifier: GPL-2.0
+#include <linux/types.h>
+#include <linux/netdevice.h>
+#include <net/dropreason.h>
+
#if LINUX_VERSION_IS_GEQ(6,2,0) && defined(CONFIG_KUNIT)
#include <kunit/test.h>
@@ -40,3 +44,12 @@ void kunit_add_cleanup(struct kunit *test, kunit_cleanup_t cleanup_func,
}
EXPORT_SYMBOL_GPL(kunit_add_cleanup);
#endif /* LINUX_VERSION_IS_GEQ(6,2,0) */
+
+void drop_reasons_register_subsys(enum skb_drop_reason_subsys subsys,
+ const struct drop_reason_list *list)
+{}
+EXPORT_SYMBOL_GPL(drop_reasons_register_subsys);
+
+void drop_reasons_unregister_subsys(enum skb_drop_reason_subsys subsys)
+{}
+EXPORT_SYMBOL_GPL(drop_reasons_unregister_subsys);