wireguard-linux/net/core/net_namespace.c, branch jd/unified-crypt-queue

bpf: Add netns cookie and enable it for bpf cgroup hooks

2020-03-28T02:40:38Z

In Cilium we're mainly using BPF cgroup hooks today in order to implement kube-proxy free Kubernetes service translation for ClusterIP, NodePort (*), ExternalIP, and LoadBalancer as well as HostPort mapping [0] for all traffic between Cilium managed nodes. While this works in its current shape and avoids packet-level NAT for inter Cilium managed node traffic, there is one major limitation we're facing today, that is, lack of netns awareness. In Kubernetes, the concept of Pods (which hold one or multiple containers) has been built around network namespaces, so while we can use the global scope of attaching to root BPF cgroup hooks also to our advantage (e.g. for exposing NodePort ports on loopback addresses), we also have the need to differentiate between initial network namespaces and non-initial one. For example, ExternalIP services mandate that non-local service IPs are not to be translated from the host (initial) network namespace as one example. Right now, we have an ugly work-around in place where non-local service IPs for ExternalIP services are not xlated from connect() and friends BPF hooks but instead via less efficient packet-level NAT on the veth tc ingress hook for Pod traffic. On top of determining whether we're in initial or non-initial network namespace we also have a need for a socket-cookie like mechanism for network namespaces scope. Socket cookies have the nice property that they can be combined as part of the key structure e.g. for BPF LRU maps without having to worry that the cookie could be recycled. We are planning to use this for our sessionAffinity implementation for services. Therefore, add a new bpf_get_netns_cookie() helper which would resolve both use cases at once: bpf_get_netns_cookie(NULL) would provide the cookie for the initial network namespace while passing the context instead of NULL would provide the cookie from the application's network namespace. We're using a hole, so no size increase; the assignment happens only once. Therefore this allows for a comparison on initial namespace as well as regular cookie usage as we have today with socket cookies. We could later on enable this helper for other program types as well as we would see need. (*) Both externalTrafficPolicy={Local|Cluster} types [0] https://github.com/cilium/cilium/blob/master/bpf/bpf_sock.c Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/c47d2346982693a9cf9da0e12690453aded4c788.1585323121.git.daniel@iogearbox.net

netns: Constify exported functions

2020-01-17T12:25:24Z

Mark function parameters as 'const' where possible. Signed-off-by: Guillaume Nault Acked-by: Nicolas Dichtel Signed-off-by: David S. Miller

netns: don't disable BHs when locking "nsid_lock"

2020-01-14T19:28:40Z

When peernet2id() had to lock "nsid_lock" before iterating through the nsid table, we had to disable BHs, because VXLAN can call peernet2id() from the xmit path: vxlan_xmit() -> vxlan_fdb_miss() -> vxlan_fdb_notify() -> __vxlan_fdb_notify() -> vxlan_fdb_info() -> peernet2id(). Now that peernet2id() uses RCU protection, "nsid_lock" isn't used in BH context anymore. Therefore, we can safely use plain spin_lock()/spin_unlock() and let BHs run when holding "nsid_lock". Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller

netns: protect netns ID lookups with RCU

2020-01-14T19:28:40Z

__peernet2id() can be protected by RCU as it only calls idr_for_each(), which is RCU-safe, and never modifies the nsid table. rtnl_net_dumpid() can also do lockless lookups. It does two nested idr_for_each() calls on nsid tables (one direct call and one indirect call because of rtnl_net_dumpid_one() calling __peernet2id()). The netnsid tables are never updated. Therefore it is safe to not take the nsid_lock and run within an RCU-critical section instead. Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller

netns: Remove __peernet2id_alloc()

2020-01-14T19:28:40Z

__peernet2id_alloc() was used for both plain lookups and for netns ID allocations (depending the value of '*alloc'). Let's separate lookups from allocations instead. That is, integrate the lookup code into __peernet2id() and make peernet2id_alloc() responsible for allocating new netns IDs when necessary. This makes it clear that __peernet2id() doesn't modify the idr and prepares the code for lockless lookups. Also, mark the 'net' argument of __peernet2id() as 'const', since we're modifying this line. Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller

netns: fix GFP flags in rtnl_net_notifyid()

2019-10-26T03:14:42Z

In rtnl_net_notifyid(), we certainly can't pass a null GFP flag to rtnl_notify(). A GFP_KERNEL flag would be fine in most circumstances, but there are a few paths calling rtnl_net_notifyid() from atomic context or from RCU critical sections. The later also precludes the use of gfp_any() as it wouldn't detect the RCU case. Also, the nlmsg_new() call is wrong too, as it uses GFP_KERNEL unconditionally. Therefore, we need to pass the GFP flags as parameter and propagate it through function calls until the proper flags can be determined. In most cases, GFP_KERNEL is fine. The exceptions are: * openvswitch: ovs_vport_cmd_get() and ovs_vport_cmd_dump() indirectly call rtnl_net_notifyid() from RCU critical section, * rtnetlink: rtmsg_ifinfo_build_skb() already receives GFP flags as parameter. Also, in ovs_vport_cmd_build_info(), let's change the GFP flags used by nlmsg_new(). The function is allowed to sleep, so better make the flags consistent with the ones used in the following ovs_vport_cmd_fill_info() call. Found by code inspection. Fixes: 9a9634545c70 ("netns: notify netns id events") Signed-off-by: Guillaume Nault Acked-by: Nicolas Dichtel Acked-by: Pravin B Shelar Signed-off-by: David S. Miller

keys: Fix memory leak in copy_net_ns

2019-10-24T21:40:02Z

If copy_net_ns() failed after net_alloc(), net->key_domain is leaked. Fix this, by freeing key_domain in error path. syzbot report: BUG: memory leak unreferenced object 0xffff8881175007e0 (size 32): comm "syz-executor902", pid 7069, jiffies 4294944350 (age 28.400s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000a83ed741>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline] [<00000000a83ed741>] slab_post_alloc_hook mm/slab.h:439 [inline] [<00000000a83ed741>] slab_alloc mm/slab.c:3326 [inline] [<00000000a83ed741>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553 [<0000000059fc92b9>] kmalloc include/linux/slab.h:547 [inline] [<0000000059fc92b9>] kzalloc include/linux/slab.h:742 [inline] [<0000000059fc92b9>] net_alloc net/core/net_namespace.c:398 [inline] [<0000000059fc92b9>] copy_net_ns+0xb2/0x220 net/core/net_namespace.c:445 [<00000000a9d74bbc>] create_new_namespaces+0x141/0x2a0 kernel/nsproxy.c:103 [<000000008047d645>] unshare_nsproxy_namespaces+0x7f/0x100 kernel/nsproxy.c:202 [<000000005993ea6e>] ksys_unshare+0x236/0x490 kernel/fork.c:2674 [<0000000019417e75>] __do_sys_unshare kernel/fork.c:2742 [inline] [<0000000019417e75>] __se_sys_unshare kernel/fork.c:2740 [inline] [<0000000019417e75>] __x64_sys_unshare+0x16/0x20 kernel/fork.c:2740 [<00000000f4c5f2c8>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:296 [<0000000038550184>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 syzbot also reported other leak in copy_net_ns -> setup_net. This problem is already fixed by cf47a0b882a4e5f6b34c7949d7b293e9287f1972. Fixes: 9b242610514f ("keys: Network namespace domain tag") Reported-and-tested-by: syzbot+3b3296d032353c33184b@syzkaller.appspotmail.com Signed-off-by: Takeshi Misawa Signed-off-by: David S. Miller

netns: fix NLM_F_ECHO mechanism for RTM_NEWNSID

2019-10-10T03:58:05Z

The flag NLM_F_ECHO aims to reply to the user the message notified to all listeners. It was not the case with the command RTM_NEWNSID, let's fix this. Fixes: 0c7aecd4bde4 ("netns: add rtnl cmd to add and get peer netns ids") Reported-by: Guillaume Nault Signed-off-by: Nicolas Dichtel Acked-by: Guillaume Nault Tested-by: Guillaume Nault Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2019-07-11T17:55:49Z

Pull networking updates from David Miller: "Some highlights from this development cycle: 1) Big refactoring of ipv6 route and neigh handling to support nexthop objects configurable as units from userspace. From David Ahern. 2) Convert explored_states in BPF verifier into a hash table, significantly decreased state held for programs with bpf2bpf calls, from Alexei Starovoitov. 3) Implement bpf_send_signal() helper, from Yonghong Song. 4) Various classifier enhancements to mvpp2 driver, from Maxime Chevallier. 5) Add aRFS support to hns3 driver, from Jian Shen. 6) Fix use after free in inet frags by allocating fqdirs dynamically and reworking how rhashtable dismantle occurs, from Eric Dumazet. 7) Add act_ctinfo packet classifier action, from Kevin Darbyshire-Bryant. 8) Add TFO key backup infrastructure, from Jason Baron. 9) Remove several old and unused ISDN drivers, from Arnd Bergmann. 10) Add devlink notifications for flash update status to mlxsw driver, from Jiri Pirko. 11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski. 12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes. 13) Various enhancements to ipv6 flow label handling, from Eric Dumazet and Willem de Bruijn. 14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van der Merwe, and others. 15) Various improvements to axienet driver including converting it to phylink, from Robert Hancock. 16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean. 17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana Radulescu. 18) Add devlink health reporting to mlx5, from Moshe Shemesh. 19) Convert stmmac over to phylink, from Jose Abreu. 20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from Shalom Toledo. 21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera. 22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel. 23) Track spill/fill of constants in BPF verifier, from Alexei Starovoitov. 24) Support bounded loops in BPF, from Alexei Starovoitov. 25) Various page_pool API fixes and improvements, from Jesper Dangaard Brouer. 26) Just like ipv4, support ref-countless ipv6 route handling. From Wei Wang. 27) Support VLAN offloading in aquantia driver, from Igor Russkikh. 28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy. 29) Add flower GRE encap/decap support to nfp driver, from Pieter Jansen van Vuuren. 30) Protect against stack overflow when using act_mirred, from John Hurley. 31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen. 32) Use page_pool API in netsec driver, Ilias Apalodimas. 33) Add Google gve network driver, from Catherine Sullivan. 34) More indirect call avoidance, from Paolo Abeni. 35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan. 36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek. 37) Add MPLS manipulation actions to TC, from John Hurley. 38) Add sending a packet to connection tracking from TC actions, and then allow flower classifier matching on conntrack state. From Paul Blakey. 39) Netfilter hw offload support, from Pablo Neira Ayuso" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits) net/mlx5e: Return in default case statement in tx_post_resync_params mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync(). net: dsa: add support for BRIDGE_MROUTER attribute pkt_sched: Include const.h net: netsec: remove static declaration for netsec_set_tx_de() net: netsec: remove superfluous if statement netfilter: nf_tables: add hardware offload support net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload net: flow_offload: add flow_block_cb_is_busy() and use it net: sched: remove tcf block API drivers: net: use flow block API net: sched: use flow block API net: flow_offload: add flow_block_cb_{priv, incref, decref}() net: flow_offload: add list handling functions net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free() net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_* net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND net: flow_offload: add flow_block_cb_setup_simple() net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC ...

Merge tag 'keys-namespace-20190627' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

2019-07-09T02:36:47Z

Pull keyring namespacing from David Howells: "These patches help make keys and keyrings more namespace aware. Firstly some miscellaneous patches to make the process easier: - Simplify key index_key handling so that the word-sized chunks assoc_array requires don't have to be shifted about, making it easier to add more bits into the key. - Cache the hash value in the key so that we don't have to calculate on every key we examine during a search (it involves a bunch of multiplications). - Allow keying_search() to search non-recursively. Then the main patches: - Make it so that keyring names are per-user_namespace from the point of view of KEYCTL_JOIN_SESSION_KEYRING so that they're not accessible cross-user_namespace. keyctl_capabilities() shows KEYCTL_CAPS1_NS_KEYRING_NAME for this. - Move the user and user-session keyrings to the user_namespace rather than the user_struct. This prevents them propagating directly across user_namespaces boundaries (ie. the KEY_SPEC_* flags will only pick from the current user_namespace). - Make it possible to include the target namespace in which the key shall operate in the index_key. This will allow the possibility of multiple keys with the same description, but different target domains to be held in the same keyring. keyctl_capabilities() shows KEYCTL_CAPS1_NS_KEY_TAG for this. - Make it so that keys are implicitly invalidated by removal of a domain tag, causing them to be garbage collected. - Institute a network namespace domain tag that allows keys to be differentiated by the network namespace in which they operate. New keys that are of a type marked 'KEY_TYPE_NET_DOMAIN' are assigned the network domain in force when they are created. - Make it so that the desired network namespace can be handed down into the request_key() mechanism. This allows AFS, NFS, etc. to request keys specific to the network namespace of the superblock. This also means that the keys in the DNS record cache are thenceforth namespaced, provided network filesystems pass the appropriate network namespace down into dns_query(). For DNS, AFS and NFS are good, whilst CIFS and Ceph are not. Other cache keyrings, such as idmapper keyrings, also need to set the domain tag - for which they need access to the network namespace of the superblock" * tag 'keys-namespace-20190627' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: keys: Pass the network namespace into request_key mechanism keys: Network namespace domain tag keys: Garbage collect keys for which the domain has been removed keys: Include target namespace in match criteria keys: Move the user and user-session keyrings to the user_namespace keys: Namespace keyring names keys: Add a 'recurse' flag for keyring searches keys: Cache the hash value to avoid lots of recalculation keys: Simplify key description management