xref: /linux/include/net/dropreason-core.h (revision 1a9239bb4253f9076b5b4b2a1a4e8d7defd77a95)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 
3 #ifndef _LINUX_DROPREASON_CORE_H
4 #define _LINUX_DROPREASON_CORE_H
5 
6 #define DEFINE_DROP_REASON(FN, FNe)	\
7 	FN(NOT_SPECIFIED)		\
8 	FN(NO_SOCKET)			\
9 	FN(SOCKET_CLOSE)		\
10 	FN(SOCKET_FILTER)		\
11 	FN(SOCKET_RCVBUFF)		\
12 	FN(UNIX_DISCONNECT)		\
13 	FN(UNIX_SKIP_OOB)		\
14 	FN(PKT_TOO_SMALL)		\
15 	FN(TCP_CSUM)			\
16 	FN(UDP_CSUM)			\
17 	FN(NETFILTER_DROP)		\
18 	FN(OTHERHOST)			\
19 	FN(IP_CSUM)			\
20 	FN(IP_INHDR)			\
21 	FN(IP_RPFILTER)			\
22 	FN(UNICAST_IN_L2_MULTICAST)	\
23 	FN(XFRM_POLICY)			\
24 	FN(IP_NOPROTO)			\
25 	FN(PROTO_MEM)			\
26 	FN(TCP_AUTH_HDR)		\
27 	FN(TCP_MD5NOTFOUND)		\
28 	FN(TCP_MD5UNEXPECTED)		\
29 	FN(TCP_MD5FAILURE)		\
30 	FN(TCP_AONOTFOUND)		\
31 	FN(TCP_AOUNEXPECTED)		\
32 	FN(TCP_AOKEYNOTFOUND)		\
33 	FN(TCP_AOFAILURE)		\
34 	FN(SOCKET_BACKLOG)		\
35 	FN(TCP_FLAGS)			\
36 	FN(TCP_ABORT_ON_DATA)		\
37 	FN(TCP_ZEROWINDOW)		\
38 	FN(TCP_OLD_DATA)		\
39 	FN(TCP_OVERWINDOW)		\
40 	FN(TCP_OFOMERGE)		\
41 	FN(TCP_RFC7323_PAWS)		\
42 	FN(TCP_RFC7323_PAWS_ACK)	\
43 	FN(TCP_RFC7323_TSECR)		\
44 	FN(TCP_LISTEN_OVERFLOW)		\
45 	FN(TCP_OLD_SEQUENCE)		\
46 	FN(TCP_INVALID_SEQUENCE)	\
47 	FN(TCP_INVALID_ACK_SEQUENCE)	\
48 	FN(TCP_RESET)			\
49 	FN(TCP_INVALID_SYN)		\
50 	FN(TCP_CLOSE)			\
51 	FN(TCP_FASTOPEN)		\
52 	FN(TCP_OLD_ACK)			\
53 	FN(TCP_TOO_OLD_ACK)		\
54 	FN(TCP_ACK_UNSENT_DATA)		\
55 	FN(TCP_OFO_QUEUE_PRUNE)		\
56 	FN(TCP_OFO_DROP)		\
57 	FN(IP_OUTNOROUTES)		\
58 	FN(BPF_CGROUP_EGRESS)		\
59 	FN(IPV6DISABLED)		\
60 	FN(NEIGH_CREATEFAIL)		\
61 	FN(NEIGH_FAILED)		\
62 	FN(NEIGH_QUEUEFULL)		\
63 	FN(NEIGH_DEAD)			\
64 	FN(TC_EGRESS)			\
65 	FN(SECURITY_HOOK)		\
66 	FN(QDISC_DROP)			\
67 	FN(QDISC_OVERLIMIT)		\
68 	FN(QDISC_CONGESTED)		\
69 	FN(CAKE_FLOOD)			\
70 	FN(FQ_BAND_LIMIT)		\
71 	FN(FQ_HORIZON_LIMIT)		\
72 	FN(FQ_FLOW_LIMIT)		\
73 	FN(CPU_BACKLOG)			\
74 	FN(XDP)				\
75 	FN(TC_INGRESS)			\
76 	FN(UNHANDLED_PROTO)		\
77 	FN(SKB_CSUM)			\
78 	FN(SKB_GSO_SEG)			\
79 	FN(SKB_UCOPY_FAULT)		\
80 	FN(DEV_HDR)			\
81 	FN(DEV_READY)			\
82 	FN(FULL_RING)			\
83 	FN(NOMEM)			\
84 	FN(HDR_TRUNC)			\
85 	FN(TAP_FILTER)			\
86 	FN(TAP_TXFILTER)		\
87 	FN(ICMP_CSUM)			\
88 	FN(INVALID_PROTO)		\
89 	FN(IP_INADDRERRORS)		\
90 	FN(IP_INNOROUTES)		\
91 	FN(IP_LOCAL_SOURCE)		\
92 	FN(IP_INVALID_SOURCE)		\
93 	FN(IP_LOCALNET)			\
94 	FN(IP_INVALID_DEST)		\
95 	FN(PKT_TOO_BIG)			\
96 	FN(DUP_FRAG)			\
97 	FN(FRAG_REASM_TIMEOUT)		\
98 	FN(FRAG_TOO_FAR)		\
99 	FN(TCP_MINTTL)			\
100 	FN(IPV6_BAD_EXTHDR)		\
101 	FN(IPV6_NDISC_FRAG)		\
102 	FN(IPV6_NDISC_HOP_LIMIT)	\
103 	FN(IPV6_NDISC_BAD_CODE)		\
104 	FN(IPV6_NDISC_BAD_OPTIONS)	\
105 	FN(IPV6_NDISC_NS_OTHERHOST)	\
106 	FN(QUEUE_PURGE)			\
107 	FN(TC_COOKIE_ERROR)		\
108 	FN(PACKET_SOCK_ERROR)		\
109 	FN(TC_CHAIN_NOTFOUND)		\
110 	FN(TC_RECLASSIFY_LOOP)		\
111 	FN(VXLAN_INVALID_HDR)		\
112 	FN(VXLAN_VNI_NOT_FOUND)		\
113 	FN(MAC_INVALID_SOURCE)		\
114 	FN(VXLAN_ENTRY_EXISTS)		\
115 	FN(NO_TX_TARGET)		\
116 	FN(IP_TUNNEL_ECN)		\
117 	FN(TUNNEL_TXINFO)		\
118 	FN(LOCAL_MAC)			\
119 	FN(ARP_PVLAN_DISABLE)		\
120 	FN(MAC_IEEE_MAC_CONTROL)	\
121 	FN(BRIDGE_INGRESS_STP_STATE)	\
122 	FNe(MAX)
123 
124 /**
125  * enum skb_drop_reason - the reasons of skb drops
126  *
127  * The reason of skb drop, which is used in kfree_skb_reason().
128  */
129 enum skb_drop_reason {
130 	/**
131 	 * @SKB_NOT_DROPPED_YET: skb is not dropped yet (used for no-drop case)
132 	 */
133 	SKB_NOT_DROPPED_YET = 0,
134 	/** @SKB_CONSUMED: packet has been consumed */
135 	SKB_CONSUMED,
136 	/** @SKB_DROP_REASON_NOT_SPECIFIED: drop reason is not specified */
137 	SKB_DROP_REASON_NOT_SPECIFIED,
138 	/**
139 	 * @SKB_DROP_REASON_NO_SOCKET: no valid socket that can be used.
140 	 * Reason could be one of three cases:
141 	 * 1) no established/listening socket found during lookup process
142 	 * 2) no valid request socket during 3WHS process
143 	 * 3) no valid child socket during 3WHS process
144 	 */
145 	SKB_DROP_REASON_NO_SOCKET,
146 	/** @SKB_DROP_REASON_SOCKET_CLOSE: socket is close()d */
147 	SKB_DROP_REASON_SOCKET_CLOSE,
148 	/** @SKB_DROP_REASON_SOCKET_FILTER: dropped by socket filter */
149 	SKB_DROP_REASON_SOCKET_FILTER,
150 	/** @SKB_DROP_REASON_SOCKET_RCVBUFF: socket receive buff is full */
151 	SKB_DROP_REASON_SOCKET_RCVBUFF,
152 	/**
153 	 * @SKB_DROP_REASON_UNIX_DISCONNECT: recv queue is purged when SOCK_DGRAM
154 	 * or SOCK_SEQPACKET socket re-connect()s to another socket or notices
155 	 * during send() that the peer has been close()d.
156 	 */
157 	SKB_DROP_REASON_UNIX_DISCONNECT,
158 	/**
159 	 * @SKB_DROP_REASON_UNIX_SKIP_OOB: Out-Of-Band data is skipped by
160 	 * recv() without MSG_OOB so dropped.
161 	 */
162 	SKB_DROP_REASON_UNIX_SKIP_OOB,
163 	/** @SKB_DROP_REASON_PKT_TOO_SMALL: packet size is too small */
164 	SKB_DROP_REASON_PKT_TOO_SMALL,
165 	/** @SKB_DROP_REASON_TCP_CSUM: TCP checksum error */
166 	SKB_DROP_REASON_TCP_CSUM,
167 	/** @SKB_DROP_REASON_UDP_CSUM: UDP checksum error */
168 	SKB_DROP_REASON_UDP_CSUM,
169 	/** @SKB_DROP_REASON_NETFILTER_DROP: dropped by netfilter */
170 	SKB_DROP_REASON_NETFILTER_DROP,
171 	/**
172 	 * @SKB_DROP_REASON_OTHERHOST: packet don't belong to current host
173 	 * (interface is in promisc mode)
174 	 */
175 	SKB_DROP_REASON_OTHERHOST,
176 	/** @SKB_DROP_REASON_IP_CSUM: IP checksum error */
177 	SKB_DROP_REASON_IP_CSUM,
178 	/**
179 	 * @SKB_DROP_REASON_IP_INHDR: there is something wrong with IP header (see
180 	 * IPSTATS_MIB_INHDRERRORS)
181 	 */
182 	SKB_DROP_REASON_IP_INHDR,
183 	/**
184 	 * @SKB_DROP_REASON_IP_RPFILTER: IP rpfilter validate failed. see the
185 	 * document for rp_filter in ip-sysctl.rst for more information
186 	 */
187 	SKB_DROP_REASON_IP_RPFILTER,
188 	/**
189 	 * @SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST: destination address of L2 is
190 	 * multicast, but L3 is unicast.
191 	 */
192 	SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST,
193 	/** @SKB_DROP_REASON_XFRM_POLICY: xfrm policy check failed */
194 	SKB_DROP_REASON_XFRM_POLICY,
195 	/** @SKB_DROP_REASON_IP_NOPROTO: no support for IP protocol */
196 	SKB_DROP_REASON_IP_NOPROTO,
197 	/**
198 	 * @SKB_DROP_REASON_PROTO_MEM: proto memory limitation, such as
199 	 * udp packet drop out of udp_memory_allocated.
200 	 */
201 	SKB_DROP_REASON_PROTO_MEM,
202 	/**
203 	 * @SKB_DROP_REASON_TCP_AUTH_HDR: TCP-MD5 or TCP-AO hashes are met
204 	 * twice or set incorrectly.
205 	 */
206 	SKB_DROP_REASON_TCP_AUTH_HDR,
207 	/**
208 	 * @SKB_DROP_REASON_TCP_MD5NOTFOUND: no MD5 hash and one expected,
209 	 * corresponding to LINUX_MIB_TCPMD5NOTFOUND
210 	 */
211 	SKB_DROP_REASON_TCP_MD5NOTFOUND,
212 	/**
213 	 * @SKB_DROP_REASON_TCP_MD5UNEXPECTED: MD5 hash and we're not expecting
214 	 * one, corresponding to LINUX_MIB_TCPMD5UNEXPECTED
215 	 */
216 	SKB_DROP_REASON_TCP_MD5UNEXPECTED,
217 	/**
218 	 * @SKB_DROP_REASON_TCP_MD5FAILURE: MD5 hash and its wrong, corresponding
219 	 * to LINUX_MIB_TCPMD5FAILURE
220 	 */
221 	SKB_DROP_REASON_TCP_MD5FAILURE,
222 	/**
223 	 * @SKB_DROP_REASON_TCP_AONOTFOUND: no TCP-AO hash and one was expected,
224 	 * corresponding to LINUX_MIB_TCPAOREQUIRED
225 	 */
226 	SKB_DROP_REASON_TCP_AONOTFOUND,
227 	/**
228 	 * @SKB_DROP_REASON_TCP_AOUNEXPECTED: TCP-AO hash is present and it
229 	 * was not expected, corresponding to LINUX_MIB_TCPAOKEYNOTFOUND
230 	 */
231 	SKB_DROP_REASON_TCP_AOUNEXPECTED,
232 	/**
233 	 * @SKB_DROP_REASON_TCP_AOKEYNOTFOUND: TCP-AO key is unknown,
234 	 * corresponding to LINUX_MIB_TCPAOKEYNOTFOUND
235 	 */
236 	SKB_DROP_REASON_TCP_AOKEYNOTFOUND,
237 	/**
238 	 * @SKB_DROP_REASON_TCP_AOFAILURE: TCP-AO hash is wrong,
239 	 * corresponding to LINUX_MIB_TCPAOBAD
240 	 */
241 	SKB_DROP_REASON_TCP_AOFAILURE,
242 	/**
243 	 * @SKB_DROP_REASON_SOCKET_BACKLOG: failed to add skb to socket backlog (
244 	 * see LINUX_MIB_TCPBACKLOGDROP)
245 	 */
246 	SKB_DROP_REASON_SOCKET_BACKLOG,
247 	/** @SKB_DROP_REASON_TCP_FLAGS: TCP flags invalid */
248 	SKB_DROP_REASON_TCP_FLAGS,
249 	/**
250 	 * @SKB_DROP_REASON_TCP_ABORT_ON_DATA: abort on data, corresponding to
251 	 * LINUX_MIB_TCPABORTONDATA
252 	 */
253 	SKB_DROP_REASON_TCP_ABORT_ON_DATA,
254 	/**
255 	 * @SKB_DROP_REASON_TCP_ZEROWINDOW: TCP receive window size is zero,
256 	 * see LINUX_MIB_TCPZEROWINDOWDROP
257 	 */
258 	SKB_DROP_REASON_TCP_ZEROWINDOW,
259 	/**
260 	 * @SKB_DROP_REASON_TCP_OLD_DATA: the TCP data received is already
261 	 * received before (spurious retrans may happened), see
262 	 * LINUX_MIB_DELAYEDACKLOST
263 	 */
264 	SKB_DROP_REASON_TCP_OLD_DATA,
265 	/**
266 	 * @SKB_DROP_REASON_TCP_OVERWINDOW: the TCP data is out of window,
267 	 * the seq of the first byte exceed the right edges of receive
268 	 * window
269 	 */
270 	SKB_DROP_REASON_TCP_OVERWINDOW,
271 	/**
272 	 * @SKB_DROP_REASON_TCP_OFOMERGE: the data of skb is already in the ofo
273 	 * queue, corresponding to LINUX_MIB_TCPOFOMERGE
274 	 */
275 	SKB_DROP_REASON_TCP_OFOMERGE,
276 	/**
277 	 * @SKB_DROP_REASON_TCP_RFC7323_PAWS: PAWS check, corresponding to
278 	 * LINUX_MIB_PAWSESTABREJECTED, LINUX_MIB_PAWSACTIVEREJECTED
279 	 */
280 	SKB_DROP_REASON_TCP_RFC7323_PAWS,
281 	/**
282 	 * @SKB_DROP_REASON_TCP_RFC7323_PAWS_ACK: PAWS check, old ACK packet.
283 	 * Corresponds to LINUX_MIB_PAWS_OLD_ACK.
284 	 */
285 	SKB_DROP_REASON_TCP_RFC7323_PAWS_ACK,
286 	/**
287 	 * @SKB_DROP_REASON_TCP_RFC7323_TSECR: PAWS check, invalid TSEcr.
288 	 * Corresponds to LINUX_MIB_TSECRREJECTED.
289 	 */
290 	SKB_DROP_REASON_TCP_RFC7323_TSECR,
291 	/** @SKB_DROP_REASON_TCP_LISTEN_OVERFLOW: listener queue full. */
292 	SKB_DROP_REASON_TCP_LISTEN_OVERFLOW,
293 	/** @SKB_DROP_REASON_TCP_OLD_SEQUENCE: Old SEQ field (duplicate packet) */
294 	SKB_DROP_REASON_TCP_OLD_SEQUENCE,
295 	/** @SKB_DROP_REASON_TCP_INVALID_SEQUENCE: Not acceptable SEQ field */
296 	SKB_DROP_REASON_TCP_INVALID_SEQUENCE,
297 	/**
298 	 * @SKB_DROP_REASON_TCP_INVALID_ACK_SEQUENCE: Not acceptable ACK SEQ
299 	 * field because ack sequence is not in the window between snd_una
300 	 * and snd_nxt
301 	 */
302 	SKB_DROP_REASON_TCP_INVALID_ACK_SEQUENCE,
303 	/** @SKB_DROP_REASON_TCP_RESET: Invalid RST packet */
304 	SKB_DROP_REASON_TCP_RESET,
305 	/**
306 	 * @SKB_DROP_REASON_TCP_INVALID_SYN: Incoming packet has unexpected
307 	 * SYN flag
308 	 */
309 	SKB_DROP_REASON_TCP_INVALID_SYN,
310 	/** @SKB_DROP_REASON_TCP_CLOSE: TCP socket in CLOSE state */
311 	SKB_DROP_REASON_TCP_CLOSE,
312 	/** @SKB_DROP_REASON_TCP_FASTOPEN: dropped by FASTOPEN request socket */
313 	SKB_DROP_REASON_TCP_FASTOPEN,
314 	/** @SKB_DROP_REASON_TCP_OLD_ACK: TCP ACK is old, but in window */
315 	SKB_DROP_REASON_TCP_OLD_ACK,
316 	/** @SKB_DROP_REASON_TCP_TOO_OLD_ACK: TCP ACK is too old */
317 	SKB_DROP_REASON_TCP_TOO_OLD_ACK,
318 	/**
319 	 * @SKB_DROP_REASON_TCP_ACK_UNSENT_DATA: TCP ACK for data we haven't
320 	 * sent yet
321 	 */
322 	SKB_DROP_REASON_TCP_ACK_UNSENT_DATA,
323 	/** @SKB_DROP_REASON_TCP_OFO_QUEUE_PRUNE: pruned from TCP OFO queue */
324 	SKB_DROP_REASON_TCP_OFO_QUEUE_PRUNE,
325 	/** @SKB_DROP_REASON_TCP_OFO_DROP: data already in receive queue */
326 	SKB_DROP_REASON_TCP_OFO_DROP,
327 	/** @SKB_DROP_REASON_IP_OUTNOROUTES: route lookup failed */
328 	SKB_DROP_REASON_IP_OUTNOROUTES,
329 	/**
330 	 * @SKB_DROP_REASON_BPF_CGROUP_EGRESS: dropped by BPF_PROG_TYPE_CGROUP_SKB
331 	 * eBPF program
332 	 */
333 	SKB_DROP_REASON_BPF_CGROUP_EGRESS,
334 	/** @SKB_DROP_REASON_IPV6DISABLED: IPv6 is disabled on the device */
335 	SKB_DROP_REASON_IPV6DISABLED,
336 	/** @SKB_DROP_REASON_NEIGH_CREATEFAIL: failed to create neigh entry */
337 	SKB_DROP_REASON_NEIGH_CREATEFAIL,
338 	/** @SKB_DROP_REASON_NEIGH_FAILED: neigh entry in failed state */
339 	SKB_DROP_REASON_NEIGH_FAILED,
340 	/** @SKB_DROP_REASON_NEIGH_QUEUEFULL: arp_queue for neigh entry is full */
341 	SKB_DROP_REASON_NEIGH_QUEUEFULL,
342 	/** @SKB_DROP_REASON_NEIGH_DEAD: neigh entry is dead */
343 	SKB_DROP_REASON_NEIGH_DEAD,
344 	/** @SKB_DROP_REASON_TC_EGRESS: dropped in TC egress HOOK */
345 	SKB_DROP_REASON_TC_EGRESS,
346 	/** @SKB_DROP_REASON_SECURITY_HOOK: dropped due to security HOOK */
347 	SKB_DROP_REASON_SECURITY_HOOK,
348 	/**
349 	 * @SKB_DROP_REASON_QDISC_DROP: dropped by qdisc when packet outputting (
350 	 * failed to enqueue to current qdisc)
351 	 */
352 	SKB_DROP_REASON_QDISC_DROP,
353 	/**
354 	 * @SKB_DROP_REASON_QDISC_OVERLIMIT: dropped by qdisc when a qdisc
355 	 * instance exceeds its total buffer size limit.
356 	 */
357 	SKB_DROP_REASON_QDISC_OVERLIMIT,
358 	/**
359 	 * @SKB_DROP_REASON_QDISC_CONGESTED: dropped by a qdisc AQM algorithm
360 	 * due to congestion.
361 	 */
362 	SKB_DROP_REASON_QDISC_CONGESTED,
363 	/**
364 	 * @SKB_DROP_REASON_CAKE_FLOOD: dropped by the flood protection part of
365 	 * CAKE qdisc AQM algorithm (BLUE).
366 	 */
367 	SKB_DROP_REASON_CAKE_FLOOD,
368 	/**
369 	 * @SKB_DROP_REASON_FQ_BAND_LIMIT: dropped by fq qdisc when per band
370 	 * limit is reached.
371 	 */
372 	SKB_DROP_REASON_FQ_BAND_LIMIT,
373 	/**
374 	 * @SKB_DROP_REASON_FQ_HORIZON_LIMIT: dropped by fq qdisc when packet
375 	 * timestamp is too far in the future.
376 	 */
377 	SKB_DROP_REASON_FQ_HORIZON_LIMIT,
378 	/**
379 	 * @SKB_DROP_REASON_FQ_FLOW_LIMIT: dropped by fq qdisc when a flow
380 	 * exceeds its limits.
381 	 */
382 	SKB_DROP_REASON_FQ_FLOW_LIMIT,
383 	/**
384 	 * @SKB_DROP_REASON_CPU_BACKLOG: failed to enqueue the skb to the per CPU
385 	 * backlog queue. This can be caused by backlog queue full (see
386 	 * netdev_max_backlog in net.rst) or RPS flow limit
387 	 */
388 	SKB_DROP_REASON_CPU_BACKLOG,
389 	/** @SKB_DROP_REASON_XDP: dropped by XDP in input path */
390 	SKB_DROP_REASON_XDP,
391 	/** @SKB_DROP_REASON_TC_INGRESS: dropped in TC ingress HOOK */
392 	SKB_DROP_REASON_TC_INGRESS,
393 	/** @SKB_DROP_REASON_UNHANDLED_PROTO: protocol not implemented or not supported */
394 	SKB_DROP_REASON_UNHANDLED_PROTO,
395 	/** @SKB_DROP_REASON_SKB_CSUM: sk_buff checksum computation error */
396 	SKB_DROP_REASON_SKB_CSUM,
397 	/** @SKB_DROP_REASON_SKB_GSO_SEG: gso segmentation error */
398 	SKB_DROP_REASON_SKB_GSO_SEG,
399 	/**
400 	 * @SKB_DROP_REASON_SKB_UCOPY_FAULT: failed to copy data from user space,
401 	 * e.g., via zerocopy_sg_from_iter() or skb_orphan_frags_rx()
402 	 */
403 	SKB_DROP_REASON_SKB_UCOPY_FAULT,
404 	/** @SKB_DROP_REASON_DEV_HDR: device driver specific header/metadata is invalid */
405 	SKB_DROP_REASON_DEV_HDR,
406 	/**
407 	 * @SKB_DROP_REASON_DEV_READY: the device is not ready to xmit/recv due to
408 	 * any of its data structure that is not up/ready/initialized,
409 	 * e.g., the IFF_UP is not set, or driver specific tun->tfiles[txq]
410 	 * is not initialized
411 	 */
412 	SKB_DROP_REASON_DEV_READY,
413 	/** @SKB_DROP_REASON_FULL_RING: ring buffer is full */
414 	SKB_DROP_REASON_FULL_RING,
415 	/** @SKB_DROP_REASON_NOMEM: error due to OOM */
416 	SKB_DROP_REASON_NOMEM,
417 	/**
418 	 * @SKB_DROP_REASON_HDR_TRUNC: failed to trunc/extract the header from
419 	 * networking data, e.g., failed to pull the protocol header from
420 	 * frags via pskb_may_pull()
421 	 */
422 	SKB_DROP_REASON_HDR_TRUNC,
423 	/**
424 	 * @SKB_DROP_REASON_TAP_FILTER: dropped by (ebpf) filter directly attached
425 	 * to tun/tap, e.g., via TUNSETFILTEREBPF
426 	 */
427 	SKB_DROP_REASON_TAP_FILTER,
428 	/**
429 	 * @SKB_DROP_REASON_TAP_TXFILTER: dropped by tx filter implemented at
430 	 * tun/tap, e.g., check_filter()
431 	 */
432 	SKB_DROP_REASON_TAP_TXFILTER,
433 	/** @SKB_DROP_REASON_ICMP_CSUM: ICMP checksum error */
434 	SKB_DROP_REASON_ICMP_CSUM,
435 	/**
436 	 * @SKB_DROP_REASON_INVALID_PROTO: the packet doesn't follow RFC 2211,
437 	 * such as a broadcasts ICMP_TIMESTAMP
438 	 */
439 	SKB_DROP_REASON_INVALID_PROTO,
440 	/**
441 	 * @SKB_DROP_REASON_IP_INADDRERRORS: host unreachable, corresponding to
442 	 * IPSTATS_MIB_INADDRERRORS
443 	 */
444 	SKB_DROP_REASON_IP_INADDRERRORS,
445 	/**
446 	 * @SKB_DROP_REASON_IP_INNOROUTES: network unreachable, corresponding to
447 	 * IPSTATS_MIB_INADDRERRORS
448 	 */
449 	SKB_DROP_REASON_IP_INNOROUTES,
450 	/** @SKB_DROP_REASON_IP_LOCAL_SOURCE: the source ip is local */
451 	SKB_DROP_REASON_IP_LOCAL_SOURCE,
452 	/**
453 	 * @SKB_DROP_REASON_IP_INVALID_SOURCE: the source ip is invalid:
454 	 * 1) source ip is multicast or limited broadcast
455 	 * 2) source ip is zero and not IGMP
456 	 */
457 	SKB_DROP_REASON_IP_INVALID_SOURCE,
458 	/** @SKB_DROP_REASON_IP_LOCALNET: source or dest ip is local net */
459 	SKB_DROP_REASON_IP_LOCALNET,
460 	/**
461 	 * @SKB_DROP_REASON_IP_INVALID_DEST: the dest ip is invalid:
462 	 * 1) dest ip is 0
463 	 */
464 	SKB_DROP_REASON_IP_INVALID_DEST,
465 	/**
466 	 * @SKB_DROP_REASON_PKT_TOO_BIG: packet size is too big (maybe exceed the
467 	 * MTU)
468 	 */
469 	SKB_DROP_REASON_PKT_TOO_BIG,
470 	/** @SKB_DROP_REASON_DUP_FRAG: duplicate fragment */
471 	SKB_DROP_REASON_DUP_FRAG,
472 	/** @SKB_DROP_REASON_FRAG_REASM_TIMEOUT: fragment reassembly timeout */
473 	SKB_DROP_REASON_FRAG_REASM_TIMEOUT,
474 	/**
475 	 * @SKB_DROP_REASON_FRAG_TOO_FAR: ipv4 fragment too far.
476 	 * (/proc/sys/net/ipv4/ipfrag_max_dist)
477 	 */
478 	SKB_DROP_REASON_FRAG_TOO_FAR,
479 	/**
480 	 * @SKB_DROP_REASON_TCP_MINTTL: ipv4 ttl or ipv6 hoplimit below
481 	 * the threshold (IP_MINTTL or IPV6_MINHOPCOUNT).
482 	 */
483 	SKB_DROP_REASON_TCP_MINTTL,
484 	/** @SKB_DROP_REASON_IPV6_BAD_EXTHDR: Bad IPv6 extension header. */
485 	SKB_DROP_REASON_IPV6_BAD_EXTHDR,
486 	/** @SKB_DROP_REASON_IPV6_NDISC_FRAG: invalid frag (suppress_frag_ndisc). */
487 	SKB_DROP_REASON_IPV6_NDISC_FRAG,
488 	/** @SKB_DROP_REASON_IPV6_NDISC_HOP_LIMIT: invalid hop limit. */
489 	SKB_DROP_REASON_IPV6_NDISC_HOP_LIMIT,
490 	/** @SKB_DROP_REASON_IPV6_NDISC_BAD_CODE: invalid NDISC icmp6 code. */
491 	SKB_DROP_REASON_IPV6_NDISC_BAD_CODE,
492 	/** @SKB_DROP_REASON_IPV6_NDISC_BAD_OPTIONS: invalid NDISC options. */
493 	SKB_DROP_REASON_IPV6_NDISC_BAD_OPTIONS,
494 	/**
495 	 * @SKB_DROP_REASON_IPV6_NDISC_NS_OTHERHOST: NEIGHBOUR SOLICITATION
496 	 * for another host.
497 	 */
498 	SKB_DROP_REASON_IPV6_NDISC_NS_OTHERHOST,
499 	/** @SKB_DROP_REASON_QUEUE_PURGE: bulk free. */
500 	SKB_DROP_REASON_QUEUE_PURGE,
501 	/**
502 	 * @SKB_DROP_REASON_TC_COOKIE_ERROR: An error occurred whilst
503 	 * processing a tc ext cookie.
504 	 */
505 	SKB_DROP_REASON_TC_COOKIE_ERROR,
506 	/**
507 	 * @SKB_DROP_REASON_PACKET_SOCK_ERROR: generic packet socket errors
508 	 * after its filter matches an incoming packet.
509 	 */
510 	SKB_DROP_REASON_PACKET_SOCK_ERROR,
511 	/** @SKB_DROP_REASON_TC_CHAIN_NOTFOUND: tc chain lookup failed. */
512 	SKB_DROP_REASON_TC_CHAIN_NOTFOUND,
513 	/**
514 	 * @SKB_DROP_REASON_TC_RECLASSIFY_LOOP: tc exceeded max reclassify loop
515 	 * iterations.
516 	 */
517 	SKB_DROP_REASON_TC_RECLASSIFY_LOOP,
518 	/**
519 	 * @SKB_DROP_REASON_VXLAN_INVALID_HDR: VXLAN header is invalid. E.g.:
520 	 * 1) reserved fields are not zero
521 	 * 2) "I" flag is not set
522 	 */
523 	SKB_DROP_REASON_VXLAN_INVALID_HDR,
524 	/** @SKB_DROP_REASON_VXLAN_VNI_NOT_FOUND: no VXLAN device found for VNI */
525 	SKB_DROP_REASON_VXLAN_VNI_NOT_FOUND,
526 	/** @SKB_DROP_REASON_MAC_INVALID_SOURCE: source mac is invalid */
527 	SKB_DROP_REASON_MAC_INVALID_SOURCE,
528 	/**
529 	 * @SKB_DROP_REASON_VXLAN_ENTRY_EXISTS: trying to migrate a static
530 	 * entry or an entry pointing to a nexthop.
531 	 */
532 	SKB_DROP_REASON_VXLAN_ENTRY_EXISTS,
533 	/** @SKB_DROP_REASON_NO_TX_TARGET: no target found for xmit */
534 	SKB_DROP_REASON_NO_TX_TARGET,
535 	/**
536 	 * @SKB_DROP_REASON_IP_TUNNEL_ECN: skb is dropped according to
537 	 * RFC 6040 4.2, see __INET_ECN_decapsulate() for detail.
538 	 */
539 	SKB_DROP_REASON_IP_TUNNEL_ECN,
540 	/**
541 	 * @SKB_DROP_REASON_TUNNEL_TXINFO: packet without necessary metadata
542 	 * reached a device which is in "external" mode.
543 	 */
544 	SKB_DROP_REASON_TUNNEL_TXINFO,
545 	/**
546 	 * @SKB_DROP_REASON_LOCAL_MAC: the source MAC address is equal to
547 	 * the MAC address of the local netdev.
548 	 */
549 	SKB_DROP_REASON_LOCAL_MAC,
550 	/**
551 	 * @SKB_DROP_REASON_ARP_PVLAN_DISABLE: packet which is not IP is
552 	 * forwarded to the in_dev, and the proxy_arp_pvlan is not
553 	 * enabled.
554 	 */
555 	SKB_DROP_REASON_ARP_PVLAN_DISABLE,
556 	/**
557 	 * @SKB_DROP_REASON_MAC_IEEE_MAC_CONTROL: the destination MAC address
558 	 * is an IEEE MAC Control address.
559 	 */
560 	SKB_DROP_REASON_MAC_IEEE_MAC_CONTROL,
561 	/**
562 	 * @SKB_DROP_REASON_BRIDGE_INGRESS_STP_STATE: the STP state of the
563 	 * ingress bridge port does not allow frames to be forwarded.
564 	 */
565 	SKB_DROP_REASON_BRIDGE_INGRESS_STP_STATE,
566 	/**
567 	 * @SKB_DROP_REASON_MAX: the maximum of core drop reasons, which
568 	 * shouldn't be used as a real 'reason' - only for tracing code gen
569 	 */
570 	SKB_DROP_REASON_MAX,
571 
572 	/**
573 	 * @SKB_DROP_REASON_SUBSYS_MASK: subsystem mask in drop reasons,
574 	 * see &enum skb_drop_reason_subsys
575 	 */
576 	SKB_DROP_REASON_SUBSYS_MASK = 0xffff0000,
577 };
578 
579 #define SKB_DROP_REASON_SUBSYS_SHIFT	16
580 
581 #define SKB_DR_INIT(name, reason)				\
582 	enum skb_drop_reason name = SKB_DROP_REASON_##reason
583 #define SKB_DR(name)						\
584 	SKB_DR_INIT(name, NOT_SPECIFIED)
585 #define SKB_DR_SET(name, reason)				\
586 	(name = SKB_DROP_REASON_##reason)
587 #define SKB_DR_OR(name, reason)					\
588 	do {							\
589 		if (name == SKB_DROP_REASON_NOT_SPECIFIED ||	\
590 		    name == SKB_NOT_DROPPED_YET)		\
591 			SKB_DR_SET(name, reason);		\
592 	} while (0)
593 
594 #endif
595