From 7151affeef8d527f50b4b68a871fd28bd660023f Mon Sep 17 00:00:00 2001 From: Taehee Yoo Date: Sat, 15 Feb 2020 10:50:21 +0000 Subject: net: export netdev_next_lower_dev_rcu() netdev_next_lower_dev_rcu() will be used to implement a function, which is to walk all lower interfaces. There are already functions that they walk their lower interface. (netdev_walk_all_lower_dev_rcu, netdev_walk_all_lower_dev()). But, there would be cases that couldn't be covered by given netdev_walk_all_lower_dev_{rcu}() function. So, some modules would want to implement own function, which is to walk all lower interfaces. In the next patch, netdev_next_lower_dev_rcu() will be used. In addition, this patch removes two unused prototypes in netdevice.h. Signed-off-by: Taehee Yoo Signed-off-by: David S. Miller --- include/linux/netdevice.h | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 9f1f633235f6..6c3f7032e8d9 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -72,6 +72,8 @@ void netdev_set_default_ethtool_ops(struct net_device *dev, #define NET_RX_SUCCESS 0 /* keep 'em coming, baby */ #define NET_RX_DROP 1 /* packet dropped */ +#define MAX_NEST_DEV 8 + /* * Transmit return codes: transmit return codes originate from three different * namespaces: @@ -4389,11 +4391,8 @@ void *netdev_lower_get_next(struct net_device *dev, ldev; \ ldev = netdev_lower_get_next(dev, &(iter))) -struct net_device *netdev_all_lower_get_next(struct net_device *dev, +struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev, struct list_head **iter); -struct net_device *netdev_all_lower_get_next_rcu(struct net_device *dev, - struct list_head **iter); - int netdev_walk_all_lower_dev(struct net_device *dev, int (*fn)(struct net_device *lower_dev, void *data), -- cgit v1.2.3 From 66256e0b15bd72e1e1c24c4cef4281a95636781c Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Sat, 15 Feb 2020 11:42:37 -0800 Subject: net/sock.h: fix all kernel-doc warnings Fix all kernel-doc warnings for . Fixes these warnings: ../include/net/sock.h:232: warning: Function parameter or member 'skc_addrpair' not described in 'sock_common' ../include/net/sock.h:232: warning: Function parameter or member 'skc_portpair' not described in 'sock_common' ../include/net/sock.h:232: warning: Function parameter or member 'skc_ipv6only' not described in 'sock_common' ../include/net/sock.h:232: warning: Function parameter or member 'skc_net_refcnt' not described in 'sock_common' ../include/net/sock.h:232: warning: Function parameter or member 'skc_v6_daddr' not described in 'sock_common' ../include/net/sock.h:232: warning: Function parameter or member 'skc_v6_rcv_saddr' not described in 'sock_common' ../include/net/sock.h:232: warning: Function parameter or member 'skc_cookie' not described in 'sock_common' ../include/net/sock.h:232: warning: Function parameter or member 'skc_listener' not described in 'sock_common' ../include/net/sock.h:232: warning: Function parameter or member 'skc_tw_dr' not described in 'sock_common' ../include/net/sock.h:232: warning: Function parameter or member 'skc_rcv_wnd' not described in 'sock_common' ../include/net/sock.h:232: warning: Function parameter or member 'skc_tw_rcv_nxt' not described in 'sock_common' ../include/net/sock.h:498: warning: Function parameter or member 'sk_rx_skb_cache' not described in 'sock' ../include/net/sock.h:498: warning: Function parameter or member 'sk_wq_raw' not described in 'sock' ../include/net/sock.h:498: warning: Function parameter or member 'tcp_rtx_queue' not described in 'sock' ../include/net/sock.h:498: warning: Function parameter or member 'sk_tx_skb_cache' not described in 'sock' ../include/net/sock.h:498: warning: Function parameter or member 'sk_route_forced_caps' not described in 'sock' ../include/net/sock.h:498: warning: Function parameter or member 'sk_txtime_report_errors' not described in 'sock' ../include/net/sock.h:498: warning: Function parameter or member 'sk_validate_xmit_skb' not described in 'sock' ../include/net/sock.h:498: warning: Function parameter or member 'sk_bpf_storage' not described in 'sock' ../include/net/sock.h:2024: warning: No description found for return value of 'sk_wmem_alloc_get' ../include/net/sock.h:2035: warning: No description found for return value of 'sk_rmem_alloc_get' ../include/net/sock.h:2046: warning: No description found for return value of 'sk_has_allocations' ../include/net/sock.h:2082: warning: No description found for return value of 'skwq_has_sleeper' ../include/net/sock.h:2244: warning: No description found for return value of 'sk_page_frag' ../include/net/sock.h:2444: warning: Function parameter or member 'tcp_rx_skb_cache_key' not described in 'DECLARE_STATIC_KEY_FALSE' ../include/net/sock.h:2444: warning: Excess function parameter 'sk' description in 'DECLARE_STATIC_KEY_FALSE' ../include/net/sock.h:2444: warning: Excess function parameter 'skb' description in 'DECLARE_STATIC_KEY_FALSE' Signed-off-by: Randy Dunlap Signed-off-by: David S. Miller --- include/net/sock.h | 38 +++++++++++++++++++++++++++++++++----- 1 file changed, 33 insertions(+), 5 deletions(-) (limited to 'include') diff --git a/include/net/sock.h b/include/net/sock.h index 02162b0378f7..328564525526 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -117,19 +117,26 @@ typedef __u64 __bitwise __addrpair; * struct sock_common - minimal network layer representation of sockets * @skc_daddr: Foreign IPv4 addr * @skc_rcv_saddr: Bound local IPv4 addr + * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr * @skc_hash: hash value used with various protocol lookup tables * @skc_u16hashes: two u16 hash values used by UDP lookup tables * @skc_dport: placeholder for inet_dport/tw_dport * @skc_num: placeholder for inet_num/tw_num + * @skc_portpair: __u32 union of @skc_dport & @skc_num * @skc_family: network address family * @skc_state: Connection state * @skc_reuse: %SO_REUSEADDR setting * @skc_reuseport: %SO_REUSEPORT setting + * @skc_ipv6only: socket is IPV6 only + * @skc_net_refcnt: socket is using net ref counting * @skc_bound_dev_if: bound device index if != 0 * @skc_bind_node: bind hash linkage for various protocol lookup tables * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol * @skc_prot: protocol handlers inside a network family * @skc_net: reference to the network namespace of this socket + * @skc_v6_daddr: IPV6 destination address + * @skc_v6_rcv_saddr: IPV6 source address + * @skc_cookie: socket's cookie value * @skc_node: main hash linkage for various protocol lookup tables * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol * @skc_tx_queue_mapping: tx queue number for this connection @@ -137,7 +144,15 @@ typedef __u64 __bitwise __addrpair; * @skc_flags: place holder for sk_flags * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings + * @skc_listener: connection request listener socket (aka rsk_listener) + * [union with @skc_flags] + * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row + * [union with @skc_flags] * @skc_incoming_cpu: record/match cpu processing incoming packets + * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled) + * [union with @skc_incoming_cpu] + * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number + * [union with @skc_incoming_cpu] * @skc_refcnt: reference count * * This is the minimal network layer representation of sockets, the header @@ -245,6 +260,7 @@ struct bpf_sk_storage; * @sk_dst_cache: destination cache * @sk_dst_pending_confirm: need to confirm neighbour * @sk_policy: flow policy + * @sk_rx_skb_cache: cache copy of recently accessed RX skb * @sk_receive_queue: incoming packets * @sk_wmem_alloc: transmit queue bytes committed * @sk_tsq_flags: TCP Small Queues flags @@ -265,6 +281,8 @@ struct bpf_sk_storage; * @sk_no_check_rx: allow zero checksum in RX packets * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK) + * @sk_route_forced_caps: static, forced route capabilities + * (set in tcp_init_sock()) * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) * @sk_gso_max_size: Maximum GSO segment size to build * @sk_gso_max_segs: Maximum number of GSO segments @@ -303,6 +321,8 @@ struct bpf_sk_storage; * @sk_frag: cached page frag * @sk_peek_off: current peek_offset value * @sk_send_head: front of stuff to transmit + * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head] + * @sk_tx_skb_cache: cache copy of recently accessed TX skb * @sk_security: used by security modules * @sk_mark: generic packet mark * @sk_cgrp_data: cgroup data for this cgroup @@ -313,11 +333,14 @@ struct bpf_sk_storage; * @sk_write_space: callback to indicate there is bf sending space available * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) * @sk_backlog_rcv: callback to process the backlog + * @sk_validate_xmit_skb: ptr to an optional validate function * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 * @sk_reuseport_cb: reuseport group container + * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage * @sk_rcu: used during RCU grace period * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME + * @sk_txtime_report_errors: set report errors mode for SO_TXTIME * @sk_txtime_unused: unused txtime flags */ struct sock { @@ -393,7 +416,9 @@ struct sock { struct sk_filter __rcu *sk_filter; union { struct socket_wq __rcu *sk_wq; + /* private: */ struct socket_wq *sk_wq_raw; + /* public: */ }; #ifdef CONFIG_XFRM struct xfrm_policy __rcu *sk_policy[2]; @@ -2017,7 +2042,7 @@ static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *fro * sk_wmem_alloc_get - returns write allocations * @sk: socket * - * Returns sk_wmem_alloc minus initial offset of one + * Return: sk_wmem_alloc minus initial offset of one */ static inline int sk_wmem_alloc_get(const struct sock *sk) { @@ -2028,7 +2053,7 @@ static inline int sk_wmem_alloc_get(const struct sock *sk) * sk_rmem_alloc_get - returns read allocations * @sk: socket * - * Returns sk_rmem_alloc + * Return: sk_rmem_alloc */ static inline int sk_rmem_alloc_get(const struct sock *sk) { @@ -2039,7 +2064,7 @@ static inline int sk_rmem_alloc_get(const struct sock *sk) * sk_has_allocations - check if allocations are outstanding * @sk: socket * - * Returns true if socket has write or read allocations + * Return: true if socket has write or read allocations */ static inline bool sk_has_allocations(const struct sock *sk) { @@ -2050,7 +2075,7 @@ static inline bool sk_has_allocations(const struct sock *sk) * skwq_has_sleeper - check if there are any waiting processes * @wq: struct socket_wq * - * Returns true if socket_wq has waiting processes + * Return: true if socket_wq has waiting processes * * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory * barrier call. They were added due to the race found within the tcp code. @@ -2238,6 +2263,9 @@ struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp, * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest * inside other socket operations and end up recursing into sk_page_frag() * while it's already in use. + * + * Return: a per task page_frag if context allows that, + * otherwise a per socket one. */ static inline struct page_frag *sk_page_frag(struct sock *sk) { @@ -2432,6 +2460,7 @@ static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) &skb_shinfo(skb)->tskey); } +DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key); /** * sk_eat_skb - Release a skb if it is no longer needed * @sk: socket to eat this skb from @@ -2440,7 +2469,6 @@ static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) * This routine must be called with interrupts disabled or with the socket * locked so that the sk_buff queue operation is ok. */ -DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key); static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) { __skb_unlink(skb, &sk->sk_receive_queue); -- cgit v1.2.3 From d2f273f0a9205257b91af1d3d461ee29688c2f24 Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Sat, 15 Feb 2020 15:34:07 -0800 Subject: skbuff.h: fix all kernel-doc warnings Fix all kernel-doc warnings in . Fixes these warnings: ../include/linux/skbuff.h:890: warning: Function parameter or member 'list' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'dev_scratch' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'ip_defrag_offset' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'skb_mstamp_ns' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member '__cloned_offset' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'head_frag' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member '__pkt_type_offset' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'encapsulation' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'encap_hdr_csum' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'csum_valid' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member '__pkt_vlan_present_offset' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'vlan_present' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'csum_complete_sw' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'csum_level' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'inner_protocol_type' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'remcsum_offload' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'sender_cpu' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'reserved_tailroom' not described in 'sk_buff' ../include/linux/skbuff.h:890: warning: Function parameter or member 'inner_ipproto' not described in 'sk_buff' Signed-off-by: Randy Dunlap Signed-off-by: David S. Miller --- include/linux/skbuff.h | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'include') diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index ca8806b69388..5b50278c4bc8 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -611,9 +611,15 @@ typedef unsigned char *sk_buff_data_t; * @next: Next buffer in list * @prev: Previous buffer in list * @tstamp: Time we arrived/left + * @skb_mstamp_ns: (aka @tstamp) earliest departure time; start point + * for retransmit timer * @rbnode: RB tree node, alternative to next/prev for netem/tcp + * @list: queue head * @sk: Socket we are owned by + * @ip_defrag_offset: (aka @sk) alternate use of @sk, used in + * fragmentation management * @dev: Device we arrived on/are leaving by + * @dev_scratch: (aka @dev) alternate use of @dev when @dev would be %NULL * @cb: Control buffer. Free for use by every layer. Put private vars here * @_skb_refdst: destination entry (with norefcount bit) * @sp: the security path, used for xfrm @@ -632,6 +638,9 @@ typedef unsigned char *sk_buff_data_t; * @pkt_type: Packet class * @fclone: skbuff clone status * @ipvs_property: skbuff is owned by ipvs + * @inner_protocol_type: whether the inner protocol is + * ENCAP_TYPE_ETHER or ENCAP_TYPE_IPPROTO + * @remcsum_offload: remote checksum offload is enabled * @offload_fwd_mark: Packet was L2-forwarded in hardware * @offload_l3_fwd_mark: Packet was L3-forwarded in hardware * @tc_skip_classify: do not classify packet. set by IFB device @@ -650,6 +659,8 @@ typedef unsigned char *sk_buff_data_t; * @tc_index: Traffic control index * @hash: the packet hash * @queue_mapping: Queue mapping for multiqueue devices + * @head_frag: skb was allocated from page fragments, + * not allocated by kmalloc() or vmalloc(). * @pfmemalloc: skbuff was allocated from PFMEMALLOC reserves * @active_extensions: active extensions (skb_ext_id types) * @ndisc_nodetype: router type (from link layer) @@ -660,15 +671,28 @@ typedef unsigned char *sk_buff_data_t; * @wifi_acked_valid: wifi_acked was set * @wifi_acked: whether frame was acked on wifi or not * @no_fcs: Request NIC to treat last 4 bytes as Ethernet FCS + * @encapsulation: indicates the inner headers in the skbuff are valid + * @encap_hdr_csum: software checksum is needed + * @csum_valid: checksum is already valid * @csum_not_inet: use CRC32c to resolve CHECKSUM_PARTIAL + * @csum_complete_sw: checksum was completed by software + * @csum_level: indicates the number of consecutive checksums found in + * the packet minus one that have been verified as + * CHECKSUM_UNNECESSARY (max 3) * @dst_pending_confirm: need to confirm neighbour * @decrypted: Decrypted SKB * @napi_id: id of the NAPI struct this skb came from + * @sender_cpu: (aka @napi_id) source CPU in XPS * @secmark: security marking * @mark: Generic packet mark + * @reserved_tailroom: (aka @mark) number of bytes of free space available + * at the tail of an sk_buff + * @vlan_present: VLAN tag is present * @vlan_proto: vlan encapsulation protocol * @vlan_tci: vlan tag control information * @inner_protocol: Protocol (encapsulation) + * @inner_ipproto: (aka @inner_protocol) stores ipproto when + * skb->inner_protocol_type == ENCAP_TYPE_IPPROTO; * @inner_transport_header: Inner transport layer header (encapsulation) * @inner_network_header: Network layer header (encapsulation) * @inner_mac_header: Link layer header (encapsulation) @@ -750,7 +774,9 @@ struct sk_buff { #endif #define CLONED_OFFSET() offsetof(struct sk_buff, __cloned_offset) + /* private: */ __u8 __cloned_offset[0]; + /* public: */ __u8 cloned:1, nohdr:1, fclone:2, @@ -775,7 +801,9 @@ struct sk_buff { #endif #define PKT_TYPE_OFFSET() offsetof(struct sk_buff, __pkt_type_offset) + /* private: */ __u8 __pkt_type_offset[0]; + /* public: */ __u8 pkt_type:3; __u8 ignore_df:1; __u8 nf_trace:1; @@ -798,7 +826,9 @@ struct sk_buff { #define PKT_VLAN_PRESENT_BIT 0 #endif #define PKT_VLAN_PRESENT_OFFSET() offsetof(struct sk_buff, __pkt_vlan_present_offset) + /* private: */ __u8 __pkt_vlan_present_offset[0]; + /* public: */ __u8 vlan_present:1; __u8 csum_complete_sw:1; __u8 csum_level:2; -- cgit v1.2.3 From 6a757c07e51f80ac34325fcd558490d2d1439e1b Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 3 Feb 2020 17:37:07 +0100 Subject: netfilter: conntrack: allow insertion of clashing entries This patch further relaxes the need to drop an skb due to a clash with an existing conntrack entry. Current clash resolution handles the case where the clash occurs between two identical entries (distinct nf_conn objects with same tuples), i.e.: Original Reply existing: 10.2.3.4:42 -> 10.8.8.8:53 10.2.3.4:42 <- 10.0.0.6:5353 clashing: 10.2.3.4:42 -> 10.8.8.8:53 10.2.3.4:42 <- 10.0.0.6:5353 ... existing handling will discard the unconfirmed clashing entry and makes skb->_nfct point to the existing one. The skb can then be processed normally just as if the clash would not have existed in the first place. For other clashes, the skb needs to be dropped. This frequently happens with DNS resolvers that send A and AAAA queries back-to-back when NAT rules are present that cause packets to get different DNAT transformations applied, for example: -m statistics --mode random ... -j DNAT --dnat-to 10.0.0.6:5353 -m statistics --mode random ... -j DNAT --dnat-to 10.0.0.7:5353 In this case the A or AAAA query is dropped which incurs a costly delay during name resolution. This patch also allows this collision type: Original Reply existing: 10.2.3.4:42 -> 10.8.8.8:53 10.2.3.4:42 <- 10.0.0.6:5353 clashing: 10.2.3.4:42 -> 10.8.8.8:53 10.2.3.4:42 <- 10.0.0.7:5353 In this case, clash is in original direction -- the reply direction is still unique. The change makes it so that when the 2nd colliding packet is received, the clashing conntrack is tagged with new IPS_NAT_CLASH_BIT, gets a fixed 1 second timeout and is inserted in the reply direction only. The entry is hidden from 'conntrack -L', it will time out quickly and it can be early dropped because it will never progress to the ASSURED state. To avoid special-casing the delete code path to special case the ORIGINAL hlist_nulls node, a new helper, "hlist_nulls_add_fake", is added so hlist_nulls_del() will work. Example: CPU A: CPU B: 1. 10.2.3.4:42 -> 10.8.8.8:53 (A) 2. 10.2.3.4:42 -> 10.8.8.8:53 (AAAA) 3. Apply DNAT, reply changed to 10.0.0.6 4. 10.2.3.4:42 -> 10.8.8.8:53 (AAAA) 5. Apply DNAT, reply changed to 10.0.0.7 6. confirm/commit to conntrack table, no collisions 7. commit clashing entry Reply comes in: 10.2.3.4:42 <- 10.0.0.6:5353 (A) -> Finds a conntrack, DNAT is reversed & packet forwarded to 10.2.3.4:42 10.2.3.4:42 <- 10.0.0.7:5353 (AAAA) -> Finds a conntrack, DNAT is reversed & packet forwarded to 10.2.3.4:42 The conntrack entry is deleted from table, as it has the NAT_CLASH bit set. In case of a retransmit from ORIGINAL dir, all further packets will get the DNAT transformation to 10.0.0.6. I tried to come up with other solutions but they all have worse problems. Alternatives considered were: 1. Confirm ct entries at allocation time, not in postrouting. a. will cause uneccesarry work when the skb that creates the conntrack is dropped by ruleset. b. in case nat is applied, ct entry would need to be moved in the table, which requires another spinlock pair to be taken. c. breaks the 'unconfirmed entry is private to cpu' assumption: we would need to guard all nfct->ext allocation requests with ct->lock spinlock. 2. Make the unconfirmed list a hash table instead of a pcpu list. Shares drawback c) of the first alternative. 3. Document this is expected and force users to rearrange their ruleset (e.g. by using "-m cluster" instead of "-m statistics"). nft has the 'jhash' expression which can be used instead of 'numgen'. Major drawback: doesn't fix what I consider a bug, not very realistic and I believe its reasonable to have the existing rulesets to 'just work'. 4. Document this is expected and force users to steer problematic packets to the same CPU -- this would serialize the "allocate new conntrack entry/nat table evaluation/perform nat/confirm entry", so no race can occur. Similar drawback to 3. Another advantage of this patch compared to 1) and 2) is that there are no changes to the hot path; things are handled in the udp tracker and the clash resolution path. Cc: rcu@vger.kernel.org Cc: "Paul E. McKenney" Cc: Josh Triplett Cc: Jozsef Kadlecsik Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- include/linux/rculist_nulls.h | 7 ++ include/uapi/linux/netfilter/nf_conntrack_common.h | 12 +++- net/netfilter/nf_conntrack_core.c | 76 +++++++++++++++++++++- net/netfilter/nf_conntrack_proto_udp.c | 20 ++++-- 4 files changed, 108 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/linux/rculist_nulls.h b/include/linux/rculist_nulls.h index e5b752027a03..9670b54b484a 100644 --- a/include/linux/rculist_nulls.h +++ b/include/linux/rculist_nulls.h @@ -145,6 +145,13 @@ static inline void hlist_nulls_add_tail_rcu(struct hlist_nulls_node *n, } } +/* after that hlist_nulls_del will work */ +static inline void hlist_nulls_add_fake(struct hlist_nulls_node *n) +{ + n->pprev = &n->next; + n->next = (struct hlist_nulls_node *)NULLS_MARKER(NULL); +} + /** * hlist_nulls_for_each_entry_rcu - iterate over rcu list of given type * @tpos: the type * to use as a loop cursor. diff --git a/include/uapi/linux/netfilter/nf_conntrack_common.h b/include/uapi/linux/netfilter/nf_conntrack_common.h index 336014bf8868..b6f0bb1dc799 100644 --- a/include/uapi/linux/netfilter/nf_conntrack_common.h +++ b/include/uapi/linux/netfilter/nf_conntrack_common.h @@ -97,6 +97,15 @@ enum ip_conntrack_status { IPS_UNTRACKED_BIT = 12, IPS_UNTRACKED = (1 << IPS_UNTRACKED_BIT), +#ifdef __KERNEL__ + /* Re-purposed for in-kernel use: + * Tags a conntrack entry that clashed with an existing entry + * on insert. + */ + IPS_NAT_CLASH_BIT = IPS_UNTRACKED_BIT, + IPS_NAT_CLASH = IPS_UNTRACKED, +#endif + /* Conntrack got a helper explicitly attached via CT target. */ IPS_HELPER_BIT = 13, IPS_HELPER = (1 << IPS_HELPER_BIT), @@ -110,7 +119,8 @@ enum ip_conntrack_status { */ IPS_UNCHANGEABLE_MASK = (IPS_NAT_DONE_MASK | IPS_NAT_MASK | IPS_EXPECTED | IPS_CONFIRMED | IPS_DYING | - IPS_SEQ_ADJUST | IPS_TEMPLATE | IPS_OFFLOAD), + IPS_SEQ_ADJUST | IPS_TEMPLATE | IPS_UNTRACKED | + IPS_OFFLOAD), __IPS_MAX_BIT = 15, }; diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 3f069eb0f0fc..1927fc296f95 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -940,11 +940,71 @@ static int __nf_ct_resolve_clash(struct sk_buff *skb, return NF_DROP; } +/** + * nf_ct_resolve_clash_harder - attempt to insert clashing conntrack entry + * + * @skb: skb that causes the collision + * @repl_idx: hash slot for reply direction + * + * Called when origin or reply direction had a clash. + * The skb can be handled without packet drop provided the reply direction + * is unique or there the existing entry has the identical tuple in both + * directions. + * + * Caller must hold conntrack table locks to prevent concurrent updates. + * + * Returns NF_DROP if the clash could not be handled. + */ +static int nf_ct_resolve_clash_harder(struct sk_buff *skb, u32 repl_idx) +{ + struct nf_conn *loser_ct = (struct nf_conn *)skb_nfct(skb); + const struct nf_conntrack_zone *zone; + struct nf_conntrack_tuple_hash *h; + struct hlist_nulls_node *n; + struct net *net; + + zone = nf_ct_zone(loser_ct); + net = nf_ct_net(loser_ct); + + /* Reply direction must never result in a clash, unless both origin + * and reply tuples are identical. + */ + hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[repl_idx], hnnode) { + if (nf_ct_key_equal(h, + &loser_ct->tuplehash[IP_CT_DIR_REPLY].tuple, + zone, net)) + return __nf_ct_resolve_clash(skb, h); + } + + /* We want the clashing entry to go away real soon: 1 second timeout. */ + loser_ct->timeout = nfct_time_stamp + HZ; + + /* IPS_NAT_CLASH removes the entry automatically on the first + * reply. Also prevents UDP tracker from moving the entry to + * ASSURED state, i.e. the entry can always be evicted under + * pressure. + */ + loser_ct->status |= IPS_FIXED_TIMEOUT | IPS_NAT_CLASH; + + __nf_conntrack_insert_prepare(loser_ct); + + /* fake add for ORIGINAL dir: we want lookups to only find the entry + * already in the table. This also hides the clashing entry from + * ctnetlink iteration, i.e. conntrack -L won't show them. + */ + hlist_nulls_add_fake(&loser_ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode); + + hlist_nulls_add_head_rcu(&loser_ct->tuplehash[IP_CT_DIR_REPLY].hnnode, + &nf_conntrack_hash[repl_idx]); + return NF_ACCEPT; +} + /** * nf_ct_resolve_clash - attempt to handle clash without packet drop * * @skb: skb that causes the clash * @h: tuplehash of the clashing entry already in table + * @hash_reply: hash slot for reply direction * * A conntrack entry can be inserted to the connection tracking table * if there is no existing entry with an identical tuple. @@ -963,10 +1023,18 @@ static int __nf_ct_resolve_clash(struct sk_buff *skb, * exactly the same, only the to-be-confirmed conntrack entry is discarded * and @skb is associated with the conntrack entry already in the table. * + * Failing that, the new, unconfirmed conntrack is still added to the table + * provided that the collision only occurs in the ORIGINAL direction. + * The new entry will be added after the existing one in the hash list, + * so packets in the ORIGINAL direction will continue to match the existing + * entry. The new entry will also have a fixed timeout so it expires -- + * due to the collision, it will not see bidirectional traffic. + * * Returns NF_DROP if the clash could not be resolved. */ static __cold noinline int -nf_ct_resolve_clash(struct sk_buff *skb, struct nf_conntrack_tuple_hash *h) +nf_ct_resolve_clash(struct sk_buff *skb, struct nf_conntrack_tuple_hash *h, + u32 reply_hash) { /* This is the conntrack entry already in hashes that won race. */ struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h); @@ -987,6 +1055,10 @@ nf_ct_resolve_clash(struct sk_buff *skb, struct nf_conntrack_tuple_hash *h) if (ret == NF_ACCEPT) return ret; + ret = nf_ct_resolve_clash_harder(skb, reply_hash); + if (ret == NF_ACCEPT) + return ret; + drop: nf_ct_add_to_dying_list(loser_ct); NF_CT_STAT_INC(net, drop); @@ -1101,7 +1173,7 @@ __nf_conntrack_confirm(struct sk_buff *skb) return NF_ACCEPT; out: - ret = nf_ct_resolve_clash(skb, h); + ret = nf_ct_resolve_clash(skb, h, reply_hash); dying: nf_conntrack_double_unlock(hash, reply_hash); local_bh_enable(); diff --git a/net/netfilter/nf_conntrack_proto_udp.c b/net/netfilter/nf_conntrack_proto_udp.c index 7365b43f8f98..760ca2422816 100644 --- a/net/netfilter/nf_conntrack_proto_udp.c +++ b/net/netfilter/nf_conntrack_proto_udp.c @@ -81,6 +81,18 @@ static bool udp_error(struct sk_buff *skb, return false; } +static void nf_conntrack_udp_refresh_unreplied(struct nf_conn *ct, + struct sk_buff *skb, + enum ip_conntrack_info ctinfo, + u32 extra_jiffies) +{ + if (unlikely(ctinfo == IP_CT_ESTABLISHED_REPLY && + ct->status & IPS_NAT_CLASH)) + nf_ct_kill(ct); + else + nf_ct_refresh_acct(ct, ctinfo, skb, extra_jiffies); +} + /* Returns verdict for packet, and may modify conntracktype */ int nf_conntrack_udp_packet(struct nf_conn *ct, struct sk_buff *skb, @@ -116,8 +128,8 @@ int nf_conntrack_udp_packet(struct nf_conn *ct, if (!test_and_set_bit(IPS_ASSURED_BIT, &ct->status)) nf_conntrack_event_cache(IPCT_ASSURED, ct); } else { - nf_ct_refresh_acct(ct, ctinfo, skb, - timeouts[UDP_CT_UNREPLIED]); + nf_conntrack_udp_refresh_unreplied(ct, skb, ctinfo, + timeouts[UDP_CT_UNREPLIED]); } return NF_ACCEPT; } @@ -198,8 +210,8 @@ int nf_conntrack_udplite_packet(struct nf_conn *ct, if (!test_and_set_bit(IPS_ASSURED_BIT, &ct->status)) nf_conntrack_event_cache(IPCT_ASSURED, ct); } else { - nf_ct_refresh_acct(ct, ctinfo, skb, - timeouts[UDP_CT_UNREPLIED]); + nf_conntrack_udp_refresh_unreplied(ct, skb, ctinfo, + timeouts[UDP_CT_UNREPLIED]); } return NF_ACCEPT; } -- cgit v1.2.3 From 8a9093c79863b58cc2f9874d7ae788f0d622a596 Mon Sep 17 00:00:00 2001 From: Jason Baron Date: Mon, 17 Feb 2020 15:38:09 -0500 Subject: net: sched: correct flower port blocking tc flower rules that are based on src or dst port blocking are sometimes ineffective due to uninitialized stack data. __skb_flow_dissect() extracts ports from the skb for tc flower to match against. However, the port dissection is not done when when the FLOW_DIS_IS_FRAGMENT bit is set in key_control->flags. All callers of __skb_flow_dissect(), zero-out the key_control field except for fl_classify() as used by the flower classifier. Thus, the FLOW_DIS_IS_FRAGMENT may be set on entry to __skb_flow_dissect(), since key_control is allocated on the stack and may not be initialized. Since key_basic and key_control are present for all flow keys, let's make sure they are initialized. Fixes: 62230715fd24 ("flow_dissector: do not dissect l4 ports for fragments") Co-developed-by: Eric Dumazet Signed-off-by: Eric Dumazet Acked-by: Cong Wang Signed-off-by: Jason Baron Signed-off-by: David S. Miller --- include/net/flow_dissector.h | 9 +++++++++ net/sched/cls_flower.c | 1 + 2 files changed, 10 insertions(+) (limited to 'include') diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h index e9391e877f9a..628383915827 100644 --- a/include/net/flow_dissector.h +++ b/include/net/flow_dissector.h @@ -5,6 +5,7 @@ #include #include #include +#include #include struct sk_buff; @@ -348,4 +349,12 @@ struct bpf_flow_dissector { void *data_end; }; +static inline void +flow_dissector_init_keys(struct flow_dissector_key_control *key_control, + struct flow_dissector_key_basic *key_basic) +{ + memset(key_control, 0, sizeof(*key_control)); + memset(key_basic, 0, sizeof(*key_basic)); +} + #endif diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index 7e54d2ab5254..d32d4233d337 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -305,6 +305,7 @@ static int fl_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct cls_fl_filter *f; list_for_each_entry_rcu(mask, &head->masks, list) { + flow_dissector_init_keys(&skb_key.control, &skb_key.basic); fl_clear_masked_range(&skb_key, mask); skb_flow_dissect_meta(skb, &mask->dissector, &skb_key); -- cgit v1.2.3 From f25975f42f2f8f2a01303054d6a70c7ceb1fcf54 Mon Sep 17 00:00:00 2001 From: Toke Høiland-Jørgensen Date: Tue, 18 Feb 2020 14:03:34 +0100 Subject: bpf, uapi: Remove text about bpf_redirect_map() giving higher performance MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The performance of bpf_redirect() is now roughly the same as that of bpf_redirect_map(). However, David Ahern pointed out that the header file has not been updated to reflect this, and still says that a significant performance increase is possible when using bpf_redirect_map(). Remove this text from the bpf_redirect_map() description, and reword the description in bpf_redirect() slightly. Also fix the 'Return' section of the bpf_redirect_map() documentation. Fixes: 1d233886dd90 ("xdp: Use bulking for non-map XDP_REDIRECT and consolidate code paths") Reported-by: David Ahern Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20200218130334.29889-1-toke@redhat.com --- include/uapi/linux/bpf.h | 16 +++++++--------- tools/include/uapi/linux/bpf.h | 16 +++++++--------- 2 files changed, 14 insertions(+), 18 deletions(-) (limited to 'include') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index f1d74a2bd234..22f235260a3a 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1045,9 +1045,9 @@ union bpf_attr { * supports redirection to the egress interface, and accepts no * flag at all. * - * The same effect can be attained with the more generic - * **bpf_redirect_map**\ (), which requires specific maps to be - * used but offers better performance. + * The same effect can also be attained with the more generic + * **bpf_redirect_map**\ (), which uses a BPF map to store the + * redirect target instead of providing it directly to the helper. * Return * For XDP, the helper returns **XDP_REDIRECT** on success or * **XDP_ABORTED** on error. For other program types, the values @@ -1611,13 +1611,11 @@ union bpf_attr { * the caller. Any higher bits in the *flags* argument must be * unset. * - * When used to redirect packets to net devices, this helper - * provides a high performance increase over **bpf_redirect**\ (). - * This is due to various implementation details of the underlying - * mechanisms, one of which is the fact that **bpf_redirect_map**\ - * () tries to send packet as a "bulk" to the device. + * See also bpf_redirect(), which only supports redirecting to an + * ifindex, but doesn't require a map to do so. * Return - * **XDP_REDIRECT** on success, or **XDP_ABORTED** on error. + * **XDP_REDIRECT** on success, or the value of the two lower bits + * of the **flags* argument on error. * * int bpf_sk_redirect_map(struct sk_buff *skb, struct bpf_map *map, u32 key, u64 flags) * Description diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index f1d74a2bd234..22f235260a3a 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1045,9 +1045,9 @@ union bpf_attr { * supports redirection to the egress interface, and accepts no * flag at all. * - * The same effect can be attained with the more generic - * **bpf_redirect_map**\ (), which requires specific maps to be - * used but offers better performance. + * The same effect can also be attained with the more generic + * **bpf_redirect_map**\ (), which uses a BPF map to store the + * redirect target instead of providing it directly to the helper. * Return * For XDP, the helper returns **XDP_REDIRECT** on success or * **XDP_ABORTED** on error. For other program types, the values @@ -1611,13 +1611,11 @@ union bpf_attr { * the caller. Any higher bits in the *flags* argument must be * unset. * - * When used to redirect packets to net devices, this helper - * provides a high performance increase over **bpf_redirect**\ (). - * This is due to various implementation details of the underlying - * mechanisms, one of which is the fact that **bpf_redirect_map**\ - * () tries to send packet as a "bulk" to the device. + * See also bpf_redirect(), which only supports redirecting to an + * ifindex, but doesn't require a map to do so. * Return - * **XDP_REDIRECT** on success, or **XDP_ABORTED** on error. + * **XDP_REDIRECT** on success, or the value of the two lower bits + * of the **flags* argument on error. * * int bpf_sk_redirect_map(struct sk_buff *skb, struct bpf_map *map, u32 key, u64 flags) * Description -- cgit v1.2.3 From 13a7e459a41a56d788ab33d825c6205379bbb711 Mon Sep 17 00:00:00 2001 From: Erez Shitrit Date: Tue, 14 Jan 2020 09:27:27 +0200 Subject: net/mlx5: DR, Handle reformat capability over sw-steering tables On flow table creation, send the relevant flags according to what the FW currently supports. When FW doesn't support reformat option over SW-steering managed table, the driver shouldn't pass this. Fixes: 988fd6b32d07 ("net/mlx5: DR, Pass table flags at creation to lower layer") Signed-off-by: Erez Shitrit Signed-off-by: Saeed Mahameed --- drivers/net/ethernet/mellanox/mlx5/core/steering/fs_dr.c | 9 +++++++-- include/linux/mlx5/mlx5_ifc.h | 5 ++++- 2 files changed, 11 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/drivers/net/ethernet/mellanox/mlx5/core/steering/fs_dr.c b/drivers/net/ethernet/mellanox/mlx5/core/steering/fs_dr.c index 3abfc8125926..c2027192e21e 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/steering/fs_dr.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/steering/fs_dr.c @@ -66,15 +66,20 @@ static int mlx5_cmd_dr_create_flow_table(struct mlx5_flow_root_namespace *ns, struct mlx5_flow_table *next_ft) { struct mlx5dr_table *tbl; + u32 flags; int err; if (mlx5_dr_is_fw_table(ft->flags)) return mlx5_fs_cmd_get_fw_cmds()->create_flow_table(ns, ft, log_size, next_ft); + flags = ft->flags; + /* turn off encap/decap if not supported for sw-str by fw */ + if (!MLX5_CAP_FLOWTABLE(ns->dev, sw_owner_reformat_supported)) + flags = ft->flags & ~(MLX5_FLOW_TABLE_TUNNEL_EN_REFORMAT | + MLX5_FLOW_TABLE_TUNNEL_EN_DECAP); - tbl = mlx5dr_table_create(ns->fs_dr_domain.dr_domain, - ft->level, ft->flags); + tbl = mlx5dr_table_create(ns->fs_dr_domain.dr_domain, ft->level, flags); if (!tbl) { mlx5_core_err(ns->dev, "Failed creating dr flow_table\n"); return -EINVAL; diff --git a/include/linux/mlx5/mlx5_ifc.h b/include/linux/mlx5/mlx5_ifc.h index ff8c9d527bb4..bfdf41537cf1 100644 --- a/include/linux/mlx5/mlx5_ifc.h +++ b/include/linux/mlx5/mlx5_ifc.h @@ -688,7 +688,10 @@ struct mlx5_ifc_flow_table_nic_cap_bits { u8 nic_rx_multi_path_tirs[0x1]; u8 nic_rx_multi_path_tirs_fts[0x1]; u8 allow_sniffer_and_nic_rx_shared_tir[0x1]; - u8 reserved_at_3[0x1d]; + u8 reserved_at_3[0x4]; + u8 sw_owner_reformat_supported[0x1]; + u8 reserved_at_8[0x18]; + u8 encap_general_header[0x1]; u8 reserved_at_21[0xa]; u8 log_max_packet_reformat_context[0x5]; -- cgit v1.2.3