kernel.git/net/ipv6/inet6_hashtables.c, branch linux-5.2.y

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

net: tcp6: prefer listeners bound to an address

2018-12-14T23:55:20Z

A relatively common use case is to have several IPs configured on a host, and have different listeners for each of them. We would like to add a "catch all" listener on addr_any, to match incoming connections not served by any of the listeners bound to a specific address. However, port-only lookups can match addr_any sockets when sockets listening on specific addresses are present if so_reuseport flag is set. This patch eliminates lookups into port-only hashtable, as lookups by (addr,port) tuple are easily available. In addition, compute_score() is tweaked to _not_ match addr_any sockets to specific addresses, as hash collisions could result in the unwanted behavior described above. Tested: the patch compiles; full test in the last patch in this patchset. Existing reuseport_* selftests also pass. Suggested-by: Eric Dumazet Signed-off-by: Peter Oskolkov Signed-off-by: David S. Miller

net: ensure unbound stream socket to be chosen when not in a VRF

2018-11-08T00:12:38Z

The commit a04a480d4392 ("net: Require exact match for TCP socket lookups if dif is l3mdev") only ensures that the correct socket is selected for packets in a VRF. However, there is no guarantee that the unbound socket will be selected for packets when not in a VRF. By checking for a device match in compute_score() also for the case when there is no bound device and attaching a score to this, the unbound socket is selected. And if a failure is returned when there is no device match, this ensures that bound sockets are never selected, even if there is no unbound socket. Signed-off-by: Mike Manning Reviewed-by: David Ahern Tested-by: David Ahern Signed-off-by: David S. Miller

bpf: Enable BPF_PROG_TYPE_SK_REUSEPORT bpf prog in reuseport selection

2018-08-10T23:58:46Z

This patch allows a BPF_PROG_TYPE_SK_REUSEPORT bpf prog to select a SO_REUSEPORT sk from a BPF_MAP_TYPE_REUSEPORT_ARRAY introduced in the earlier patch. "bpf_run_sk_reuseport()" will return -ECONNREFUSED when the BPF_PROG_TYPE_SK_REUSEPORT prog returns SK_DROP. The callers, in inet[6]_hashtable.c and ipv[46]/udp.c, are modified to handle this case and return NULL immediately instead of continuing the sk search from its hashtable. It re-uses the existing SO_ATTACH_REUSEPORT_EBPF setsockopt to attach BPF_PROG_TYPE_SK_REUSEPORT. The "sk_reuseport_attach_bpf()" will check if the attaching bpf prog is in the new SK_REUSEPORT or the existing SOCKET_FILTER type and then check different things accordingly. One level of "__reuseport_attach_prog()" call is removed. The "sk_unhashed() && ..." and "sk->sk_reuseport_cb" tests are pushed back to "reuseport_attach_prog()" in sock_reuseport.c. sock_reuseport.c seems to have more knowledge on those test requirements than filter.c. In "reuseport_attach_prog()", after new_prog is attached to reuse->prog, the old_prog (if any) is also directly freed instead of returning the old_prog to the caller and asking the caller to free. The sysctl_optmem_max check is moved back to the "sk_reuseport_attach_filter()" and "sk_reuseport_attach_bpf()". As of other bpf prog types, the new BPF_PROG_TYPE_SK_REUSEPORT is only bounded by the usual "bpf_prog_charge_memlock()" during load time instead of bounded by both bpf_prog_charge_memlock and sysctl_optmem_max. Signed-off-by: Martin KaFai Lau Acked-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann

net/tcp: Fix socket lookups with SO_BINDTODEVICE

2018-06-19T23:03:06Z

Similar to 69678bcd4d2d ("udp: fix SO_BINDTODEVICE"), TCP socket lookups need to fail if dev_match is not true. Currently, a packet to a given port can match a socket bound to device when it should not. In the VRF case, this causes the lookup to hit a VRF socket and not a global socket resulting in a response trying to go through the VRF when it should not. Fixes: 3fa6f616a7a4d ("net: ipv4: add second dif to inet socket lookups") Fixes: 4297a0ef08572 ("net: ipv6: add second dif to inet6 socket lookups") Reported-by: Lou Berger Diagnosed-by: Renato Westphal Tested-by: Renato Westphal Signed-off-by: David Ahern Signed-off-by: David S. Miller

inet: Add a 2nd listener hashtable (port+addr)

2017-12-03T15:18:28Z

The current listener hashtable is hashed by port only. When a process is listening at many IP addresses with the same port (e.g. [IP1]:443, [IP2]:443... [IPN]:443), the inet[6]_lookup_listener() performance is degraded to a link list. It is prone to syn attack. UDP had a similar issue and a second hashtable was added to resolve it. This patch adds a second hashtable for the listener's sockets. The second hashtable is hashed by port and address. It cannot reuse the existing skc_portaddr_node which is shared with skc_bind_node. TCP listener needs to use skc_bind_node. Instead, this patch adds a hlist_node 'icsk_listen_portaddr_node' to the inet_connection_sock which the listener (like TCP) also belongs to. The new portaddr hashtable may need two lookup (First by IP:PORT. Second by INADDR_ANY:PORT if the IP:PORT is a not found). Hence, it implements a similar cut off as UDP such that it will only consult the new portaddr hashtable if the current port-only hashtable has >10 sk in the link-list. lhash2 and lhash2_mask are added to 'struct inet_hashinfo'. I take this chance to plug a 4 bytes hole. It is done by first moving the existing bind_bucket_cachep up and then add the new (int lhash2_mask, *lhash2) after the existing bhash_size. Signed-off-by: Martin KaFai Lau Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller

net/reuseport: drop legacy code

2017-11-30T15:56:32Z

Since commit e32ea7e74727 ("soreuseport: fast reuseport UDP socket selection") and commit c125e80b8868 ("soreuseport: fast reuseport TCP socket selection") the relevant reuseport socket matching the current packet is selected by the reuseport_select_sock() call. The only exceptions are invalid BPF filters/filters returning out-of-range indices. In the latter case the code implicitly falls back to using the hash demultiplexing, but instead of selecting the socket inside the reuseport_select_sock() function, it relies on the hash selection logic introduced with the early soreuseport implementation. With this patch, in case of a BPF filter returning a bad socket index value, we fall back to hash-based selection inside the reuseport_select_sock() body, so that we can drop some duplicate code in the ipv4 and ipv6 stack. This also allows faster lookup in the above scenario and will allow us to avoid computing the hash value for successful, BPF based demultiplexing - in a later patch. Signed-off-by: Paolo Abeni Acked-by: Craig Gallek Signed-off-by: David S. Miller

net: ipv6: add second dif to inet6 socket lookups

2017-08-07T18:39:22Z

Add a second device index, sdif, to inet6 socket lookups. sdif is the index for ingress devices enslaved to an l3mdev. It allows the lookups to consider the enslaved device as well as the L3 domain when searching for a socket. TCP moves the data in the cb. Prior to tcp_v4_rcv (e.g., early demux) the ingress index is obtained from IPCB using inet_sdif and after tcp_v4_rcv tcp_v4_sdif is used. Signed-off-by: David Ahern Signed-off-by: David S. Miller

net: convert sock.sk_refcnt from atomic_t to refcount_t

2017-07-01T14:39:08Z

refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. This patch uses refcount_inc_not_zero() instead of atomic_inc_not_zero_hint() due to absense of a _hint() version of refcount API. If the hint() version must be used, we might need to revisit API. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor Signed-off-by: David S. Miller

inet: collapse ipv4/v6 rcv_saddr_equal functions into one

2017-01-18T18:04:28Z

We pass these per-protocol equal functions around in various places, but we can just have one function that checks the sk->sk_family and then do the right comparison function. I've also changed the ipv4 version to not cast to inet_sock since it is unneeded. Signed-off-by: Josef Bacik Signed-off-by: David S. Miller