1/* SPDX-License-Identifier: GPL-2.0-or-later */
2
3#ifndef _LINUX_DROPREASON_H
4#define _LINUX_DROPREASON_H
5
6/**
7 * enum skb_drop_reason - the reasons of skb drops
8 *
9 * The reason of skb drop, which is used in kfree_skb_reason().
10 */
11enum skb_drop_reason {
12 /**
13 * @SKB_NOT_DROPPED_YET: skb is not dropped yet (used for no-drop case)
14 */
15 SKB_NOT_DROPPED_YET = 0,
16 /** @SKB_DROP_REASON_NOT_SPECIFIED: drop reason is not specified */
17 SKB_DROP_REASON_NOT_SPECIFIED,
18 /** @SKB_DROP_REASON_NO_SOCKET: socket not found */
19 SKB_DROP_REASON_NO_SOCKET,
20 /** @SKB_DROP_REASON_PKT_TOO_SMALL: packet size is too small */
21 SKB_DROP_REASON_PKT_TOO_SMALL,
22 /** @SKB_DROP_REASON_TCP_CSUM: TCP checksum error */
23 SKB_DROP_REASON_TCP_CSUM,
24 /** @SKB_DROP_REASON_SOCKET_FILTER: dropped by socket filter */
25 SKB_DROP_REASON_SOCKET_FILTER,
26 /** @SKB_DROP_REASON_UDP_CSUM: UDP checksum error */
27 SKB_DROP_REASON_UDP_CSUM,
28 /** @SKB_DROP_REASON_NETFILTER_DROP: dropped by netfilter */
29 SKB_DROP_REASON_NETFILTER_DROP,
30 /**
31 * @SKB_DROP_REASON_OTHERHOST: packet don't belong to current host
32 * (interface is in promisc mode)
33 */
34 SKB_DROP_REASON_OTHERHOST,
35 /** @SKB_DROP_REASON_IP_CSUM: IP checksum error */
36 SKB_DROP_REASON_IP_CSUM,
37 /**
38 * @SKB_DROP_REASON_IP_INHDR: there is something wrong with IP header (see
39 * IPSTATS_MIB_INHDRERRORS)
40 */
41 SKB_DROP_REASON_IP_INHDR,
42 /**
43 * @SKB_DROP_REASON_IP_RPFILTER: IP rpfilter validate failed. see the
44 * document for rp_filter in ip-sysctl.rst for more information
45 */
46 SKB_DROP_REASON_IP_RPFILTER,
47 /**
48 * @SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST: destination address of L2 is
49 * multicast, but L3 is unicast.
50 */
51 SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST,
52 /** @SKB_DROP_REASON_XFRM_POLICY: xfrm policy check failed */
53 SKB_DROP_REASON_XFRM_POLICY,
54 /** @SKB_DROP_REASON_IP_NOPROTO: no support for IP protocol */
55 SKB_DROP_REASON_IP_NOPROTO,
56 /** @SKB_DROP_REASON_SOCKET_RCVBUFF: socket receive buff is full */
57 SKB_DROP_REASON_SOCKET_RCVBUFF,
58 /**
59 * @SKB_DROP_REASON_PROTO_MEM: proto memory limition, such as udp packet
60 * drop out of udp_memory_allocated.
61 */
62 SKB_DROP_REASON_PROTO_MEM,
63 /**
64 * @SKB_DROP_REASON_TCP_MD5NOTFOUND: no MD5 hash and one expected,
65 * corresponding to LINUX_MIB_TCPMD5NOTFOUND
66 */
67 SKB_DROP_REASON_TCP_MD5NOTFOUND,
68 /**
69 * @SKB_DROP_REASON_TCP_MD5UNEXPECTED: MD5 hash and we're not expecting
70 * one, corresponding to LINUX_MIB_TCPMD5UNEXPECTED
71 */
72 SKB_DROP_REASON_TCP_MD5UNEXPECTED,
73 /**
74 * @SKB_DROP_REASON_TCP_MD5FAILURE: MD5 hash and its wrong, corresponding
75 * to LINUX_MIB_TCPMD5FAILURE
76 */
77 SKB_DROP_REASON_TCP_MD5FAILURE,
78 /**
79 * @SKB_DROP_REASON_SOCKET_BACKLOG: failed to add skb to socket backlog (
80 * see LINUX_MIB_TCPBACKLOGDROP)
81 */
82 SKB_DROP_REASON_SOCKET_BACKLOG,
83 /** @SKB_DROP_REASON_TCP_FLAGS: TCP flags invalid */
84 SKB_DROP_REASON_TCP_FLAGS,
85 /**
86 * @SKB_DROP_REASON_TCP_ZEROWINDOW: TCP receive window size is zero,
87 * see LINUX_MIB_TCPZEROWINDOWDROP
88 */
89 SKB_DROP_REASON_TCP_ZEROWINDOW,
90 /**
91 * @SKB_DROP_REASON_TCP_OLD_DATA: the TCP data reveived is already
92 * received before (spurious retrans may happened), see
93 * LINUX_MIB_DELAYEDACKLOST
94 */
95 SKB_DROP_REASON_TCP_OLD_DATA,
96 /**
97 * @SKB_DROP_REASON_TCP_OVERWINDOW: the TCP data is out of window,
98 * the seq of the first byte exceed the right edges of receive
99 * window
100 */
101 SKB_DROP_REASON_TCP_OVERWINDOW,
102 /**
103 * @SKB_DROP_REASON_TCP_OFOMERGE: the data of skb is already in the ofo
104 * queue, corresponding to LINUX_MIB_TCPOFOMERGE
105 */
106 SKB_DROP_REASON_TCP_OFOMERGE,
107 /**
108 * @SKB_DROP_REASON_TCP_RFC7323_PAWS: PAWS check, corresponding to
109 * LINUX_MIB_PAWSESTABREJECTED
110 */
111 SKB_DROP_REASON_TCP_RFC7323_PAWS,
112 /** @SKB_DROP_REASON_TCP_INVALID_SEQUENCE: Not acceptable SEQ field */
113 SKB_DROP_REASON_TCP_INVALID_SEQUENCE,
114 /** @SKB_DROP_REASON_TCP_RESET: Invalid RST packet */
115 SKB_DROP_REASON_TCP_RESET,
116 /**
117 * @SKB_DROP_REASON_TCP_INVALID_SYN: Incoming packet has unexpected
118 * SYN flag
119 */
120 SKB_DROP_REASON_TCP_INVALID_SYN,
121 /** @SKB_DROP_REASON_TCP_CLOSE: TCP socket in CLOSE state */
122 SKB_DROP_REASON_TCP_CLOSE,
123 /** @SKB_DROP_REASON_TCP_FASTOPEN: dropped by FASTOPEN request socket */
124 SKB_DROP_REASON_TCP_FASTOPEN,
125 /** @SKB_DROP_REASON_TCP_OLD_ACK: TCP ACK is old, but in window */
126 SKB_DROP_REASON_TCP_OLD_ACK,
127 /** @SKB_DROP_REASON_TCP_TOO_OLD_ACK: TCP ACK is too old */
128 SKB_DROP_REASON_TCP_TOO_OLD_ACK,
129 /**
130 * @SKB_DROP_REASON_TCP_ACK_UNSENT_DATA: TCP ACK for data we haven't
131 * sent yet
132 */
133 SKB_DROP_REASON_TCP_ACK_UNSENT_DATA,
134 /** @SKB_DROP_REASON_TCP_OFO_QUEUE_PRUNE: pruned from TCP OFO queue */
135 SKB_DROP_REASON_TCP_OFO_QUEUE_PRUNE,
136 /** @SKB_DROP_REASON_TCP_OFO_DROP: data already in receive queue */
137 SKB_DROP_REASON_TCP_OFO_DROP,
138 /** @SKB_DROP_REASON_IP_OUTNOROUTES: route lookup failed */
139 SKB_DROP_REASON_IP_OUTNOROUTES,
140 /**
141 * @SKB_DROP_REASON_BPF_CGROUP_EGRESS: dropped by BPF_PROG_TYPE_CGROUP_SKB
142 * eBPF program
143 */
144 SKB_DROP_REASON_BPF_CGROUP_EGRESS,
145 /** @SKB_DROP_REASON_IPV6DISABLED: IPv6 is disabled on the device */
146 SKB_DROP_REASON_IPV6DISABLED,
147 /** @SKB_DROP_REASON_NEIGH_CREATEFAIL: failed to create neigh entry */
148 SKB_DROP_REASON_NEIGH_CREATEFAIL,
149 /** @SKB_DROP_REASON_NEIGH_FAILED: neigh entry in failed state */
150 SKB_DROP_REASON_NEIGH_FAILED,
151 /** @SKB_DROP_REASON_NEIGH_QUEUEFULL: arp_queue for neigh entry is full */
152 SKB_DROP_REASON_NEIGH_QUEUEFULL,
153 /** @SKB_DROP_REASON_NEIGH_DEAD: neigh entry is dead */
154 SKB_DROP_REASON_NEIGH_DEAD,
155 /** @SKB_DROP_REASON_TC_EGRESS: dropped in TC egress HOOK */
156 SKB_DROP_REASON_TC_EGRESS,
157 /**
158 * @SKB_DROP_REASON_QDISC_DROP: dropped by qdisc when packet outputting (
159 * failed to enqueue to current qdisc)
160 */
161 SKB_DROP_REASON_QDISC_DROP,
162 /**
163 * @SKB_DROP_REASON_CPU_BACKLOG: failed to enqueue the skb to the per CPU
164 * backlog queue. This can be caused by backlog queue full (see
165 * netdev_max_backlog in net.rst) or RPS flow limit
166 */
167 SKB_DROP_REASON_CPU_BACKLOG,
168 /** @SKB_DROP_REASON_XDP: dropped by XDP in input path */
169 SKB_DROP_REASON_XDP,
170 /** @SKB_DROP_REASON_TC_INGRESS: dropped in TC ingress HOOK */
171 SKB_DROP_REASON_TC_INGRESS,
172 /** @SKB_DROP_REASON_UNHANDLED_PROTO: protocol not implemented or not supported */
173 SKB_DROP_REASON_UNHANDLED_PROTO,
174 /** @SKB_DROP_REASON_SKB_CSUM: sk_buff checksum computation error */
175 SKB_DROP_REASON_SKB_CSUM,
176 /** @SKB_DROP_REASON_SKB_GSO_SEG: gso segmentation error */
177 SKB_DROP_REASON_SKB_GSO_SEG,
178 /**
179 * @SKB_DROP_REASON_SKB_UCOPY_FAULT: failed to copy data from user space,
180 * e.g., via zerocopy_sg_from_iter() or skb_orphan_frags_rx()
181 */
182 SKB_DROP_REASON_SKB_UCOPY_FAULT,
183 /** @SKB_DROP_REASON_DEV_HDR: device driver specific header/metadata is invalid */
184 SKB_DROP_REASON_DEV_HDR,
185 /**
186 * @SKB_DROP_REASON_DEV_READY: the device is not ready to xmit/recv due to
187 * any of its data structure that is not up/ready/initialized,
188 * e.g., the IFF_UP is not set, or driver specific tun->tfiles[txq]
189 * is not initialized
190 */
191 SKB_DROP_REASON_DEV_READY,
192 /** @SKB_DROP_REASON_FULL_RING: ring buffer is full */
193 SKB_DROP_REASON_FULL_RING,
194 /** @SKB_DROP_REASON_NOMEM: error due to OOM */
195 SKB_DROP_REASON_NOMEM,
196 /**
197 * @SKB_DROP_REASON_HDR_TRUNC: failed to trunc/extract the header from
198 * networking data, e.g., failed to pull the protocol header from
199 * frags via pskb_may_pull()
200 */
201 SKB_DROP_REASON_HDR_TRUNC,
202 /**
203 * @SKB_DROP_REASON_TAP_FILTER: dropped by (ebpf) filter directly attached
204 * to tun/tap, e.g., via TUNSETFILTEREBPF
205 */
206 SKB_DROP_REASON_TAP_FILTER,
207 /**
208 * @SKB_DROP_REASON_TAP_TXFILTER: dropped by tx filter implemented at
209 * tun/tap, e.g., check_filter()
210 */
211 SKB_DROP_REASON_TAP_TXFILTER,
212 /** @SKB_DROP_REASON_ICMP_CSUM: ICMP checksum error */
213 SKB_DROP_REASON_ICMP_CSUM,
214 /**
215 * @SKB_DROP_REASON_INVALID_PROTO: the packet doesn't follow RFC 2211,
216 * such as a broadcasts ICMP_TIMESTAMP
217 */
218 SKB_DROP_REASON_INVALID_PROTO,
219 /**
220 * @SKB_DROP_REASON_IP_INADDRERRORS: host unreachable, corresponding to
221 * IPSTATS_MIB_INADDRERRORS
222 */
223 SKB_DROP_REASON_IP_INADDRERRORS,
224 /**
225 * @SKB_DROP_REASON_IP_INNOROUTES: network unreachable, corresponding to
226 * IPSTATS_MIB_INADDRERRORS
227 */
228 SKB_DROP_REASON_IP_INNOROUTES,
229 /**
230 * @SKB_DROP_REASON_PKT_TOO_BIG: packet size is too big (maybe exceed the
231 * MTU)
232 */
233 SKB_DROP_REASON_PKT_TOO_BIG,
234 /**
235 * @SKB_DROP_REASON_MAX: the maximum of drop reason, which shouldn't be
236 * used as a real 'reason'
237 */
238 SKB_DROP_REASON_MAX,
239};
240
241#define SKB_DR_INIT(name, reason) \
242 enum skb_drop_reason name = SKB_DROP_REASON_##reason
243#define SKB_DR(name) \
244 SKB_DR_INIT(name, NOT_SPECIFIED)
245#define SKB_DR_SET(name, reason) \
246 (name = SKB_DROP_REASON_##reason)
247#define SKB_DR_OR(name, reason) \
248 do { \
249 if (name == SKB_DROP_REASON_NOT_SPECIFIED || \
250 name == SKB_NOT_DROPPED_YET) \
251 SKB_DR_SET(name, reason); \
252 } while (0)
253
254extern const char * const drop_reasons[];
255
256#endif
257

source code of linux/include/net/dropreason.h