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* net: orphan frags on stand-alone ptype in dev_queue_xmit_nitWillem de Bruijn2017-09-221-2/+6
| | | | | | | | | | | | | | | | | | | | Zerocopy skbs frags are copied when the skb is looped to a local sock. Commit 1080e512d44d ("net: orphan frags on receive") introduced calls to skb_orphan_frags to deliver_skb and __netif_receive_skb for this. With msg_zerocopy, these skbs can also exist in the tx path and thus loop from dev_queue_xmit_nit. This already calls deliver_skb in its loop. But it does not orphan before a separate pt_prev->func(). Add the missing skb_orphan_frags_rx. Changes v1->v2: handle skb_orphan_frags_rx failure Fixes: 1f8b977ab32d ("sock: enable MSG_ZEROCOPY") Signed-off-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: ethtool: Add back transceiver typeFlorian Fainelli2017-09-211-0/+2
| | | | | | | | | | | | | | | | | | | | | | Commit 3f1ac7a700d0 ("net: ethtool: add new ETHTOOL_xLINKSETTINGS API") deprecated the ethtool_cmd::transceiver field, which was fine in premise, except that the PHY library was actually using it to report the type of transceiver: internal or external. Use the first word of the reserved field to put this __u8 transceiver field back in. It is made read-only, and we don't expect the ETHTOOL_xLINKSETTINGS API to be doing anything with this anyway, so this is mostly for the legacy path where we do: ethtool_get_settings() -> dev->ethtool_ops->get_link_ksettings() -> convert_link_ksettings_to_legacy_settings() to have no information loss compared to the legacy get_settings API. Fixes: 3f1ac7a700d0 ("net: ethtool: add new ETHTOOL_xLINKSETTINGS API") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: change skb->mac_header when Generic XDP calls adjust_headEdward Cree2017-09-201-0/+1
| | | | | | | | | | | | | Since XDP's view of the packet includes the MAC header, moving the start- of-packet with bpf_xdp_adjust_head needs to also update the offset of the MAC header (which is relative to skb->head, not to the skb->data that was changed). Without this, tcpdump sees packets starting from the old MAC header rather than the new one, at least in my tests on the loopback device. Fixes: b5cdae3291f7 ("net: Generic XDP") Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* bpf: fix ri->map_owner pointer on bpf_prog_reallocDaniel Borkmann2017-09-191-9/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 109980b894e9 ("bpf: don't select potentially stale ri->map from buggy xdp progs") passed the pointer to the prog itself to be loaded into r4 prior on bpf_redirect_map() helper call, so that we can store the owner into ri->map_owner out of the helper. Issue with that is that the actual address of the prog is still subject to change when subsequent rewrites occur that require slow path in bpf_prog_realloc() to alloc more memory, e.g. from patching inlining helper functions or constant blinding. Thus, we really need to take prog->aux as the address we're holding, which also works with prog clones as they share the same aux object. Instead of then fetching aux->prog during runtime, which could potentially incur cache misses due to false sharing, we are going to just use aux for comparison on the map owner. This will also keep the patchlet of the same size, and later check in xdp_map_invalid() only accesses read-only aux pointer from the prog, it's also in the same cacheline already from prior access when calling bpf_func. Fixes: 109980b894e9 ("bpf: don't select potentially stale ri->map from buggy xdp progs") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* net_sched: gen_estimator: fix scaling error in bytes/packets samplesEric Dumazet2017-09-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Denys reported wrong rate estimations with HTB classes. It appears the bug was added in linux-4.10, since my tests where using intervals of one second only. HTB using 4 sec default rate estimators, reported rates were 4x higher. We need to properly scale the bytes/packets samples before integrating them in EWMA. Tested: echo 1 >/sys/module/sch_htb/parameters/htb_rate_est Setup HTB with one class with a rate/cail of 5Gbit Generate traffic on this class tc -s -d cl sh dev eth0 classid 7002:11 class htb 7002:11 parent 7002:1 prio 5 quantum 200000 rate 5Gbit ceil 5Gbit linklayer ethernet burst 80000b/1 mpu 0b cburst 80000b/1 mpu 0b level 0 rate_handle 1 Sent 1488215421648 bytes 982969243 pkt (dropped 0, overlimits 0 requeues 0) rate 5Gbit 412814pps backlog 136260b 2p requeues 0 TCP pkts/rtx 982969327/45 bytes 1488215557414/68130 lended: 22732826 borrowed: 0 giants: 0 tokens: -1684 ctokens: -1684 Fixes: 1c0d32fde5bd ("net_sched: gen_estimator: complete rewrite of rate estimators") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Denys Fedoryshchenko <nuclearcat@nuclearcat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* xdp: implement xdp_redirect_map for generic XDPJesper Dangaard Brouer2017-09-111-12/+26
| | | | | | | | | | | | | | | | | | | | | | | | Using bpf_redirect_map is allowed for generic XDP programs, but the appropriate map lookup was never performed in xdp_do_generic_redirect(). Instead the map-index is directly used as the ifindex. For the xdp_redirect_map sample in SKB-mode '-S', this resulted in trying sending on ifindex 0 which isn't valid, resulting in getting SKB packets dropped. Thus, the reported performance numbers are wrong in commit 24251c264798 ("samples/bpf: add option for native and skb mode for redirect apps") for the 'xdp_redirect_map -S' case. Before commit 109980b894e9 ("bpf: don't select potentially stale ri->map from buggy xdp progs") it could crash the kernel. Like this commit also check that the map_owner owner is correct before dereferencing the map pointer. But make sure that this API misusage can be caught by a tracepoint. Thus, allowing userspace via tracepoints to detect misbehaving bpf_progs. Fixes: 6103aa96ec07 ("net: implement XDP_REDIRECT for xdp generic") Fixes: 24251c264798 ("samples/bpf: add option for native and skb mode for redirect apps") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds2017-09-093-18/+43
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking fixes from David Miller: "The iwlwifi firmware compat fix is in here as well as some other stuff: 1) Fix request socket leak introduced by BPF deadlock fix, from Eric Dumazet. 2) Fix VLAN handling with TXQs in mac80211, from Johannes Berg. 3) Missing __qdisc_drop conversions in prio and qfq schedulers, from Gao Feng. 4) Use after free in netlink nlk groups handling, from Xin Long. 5) Handle MTU update properly in ipv6 gre tunnels, from Xin Long. 6) Fix leak of ipv6 fib tables on netns teardown, from Sabrina Dubroca with follow-on fix from Eric Dumazet. 7) Need RCU and preemption disabled during generic XDP data patch, from John Fastabend" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (54 commits) bpf: make error reporting in bpf_warn_invalid_xdp_action more clear Revert "mdio_bus: Remove unneeded gpiod NULL check" bpf: devmap, use cond_resched instead of cpu_relax bpf: add support for sockmap detach programs net: rcu lock and preempt disable missing around generic xdp bpf: don't select potentially stale ri->map from buggy xdp progs net: tulip: Constify tulip_tbl net: ethernet: ti: netcp_core: no need in netif_napi_del davicom: Display proper debug level up to 6 net: phy: sfp: rename dt properties to match the binding dt-binding: net: sfp binding documentation dt-bindings: add SFF vendor prefix dt-bindings: net: don't confuse with generic PHY property ip6_tunnel: fix setting hop_limit value for ipv6 tunnel ip_tunnel: fix setting ttl and tos value in collect_md mode ipv6: fix typo in fib6_net_exit() tcp: fix a request socket leak sctp: fix missing wake ups in some situations netfilter: xt_hashlimit: fix build error caused by 64bit division netfilter: xt_hashlimit: alloc hashtable with right size ...
| * bpf: make error reporting in bpf_warn_invalid_xdp_action more clearDaniel Borkmann2017-09-081-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Differ between illegal XDP action code and just driver unsupported one to provide better feedback when we throw a one-time warning here. Reason is that with 814abfabef3c ("xdp: add bpf_redirect helper function") not all drivers support the new XDP return code yet and thus they will fall into their 'default' case when checking for return codes after program return, which then triggers a bpf_warn_invalid_xdp_action() stating that the return code is illegal, but from XDP perspective it's not. I decided not to place something like a XDP_ACT_MAX define into uapi i) given we don't have this either for all other program types, ii) future action codes could have further encoding there, which would render such define unsuitable and we wouldn't be able to rip it out again, and iii) we rarely add new action codes. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: rcu lock and preempt disable missing around generic xdpJohn Fastabend2017-09-081-9/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | do_xdp_generic must be called inside rcu critical section with preempt disabled to ensure BPF programs are valid and per-cpu variables used for redirect operations are consistent. This patch ensures this is true and fixes the splat below. The netif_receive_skb_internal() code path is now broken into two rcu critical sections. I decided it was better to limit the preempt_enable/disable block to just the xdp static key portion and the fallout is more rcu_read_lock/unlock calls. Seems like the best option to me. [ 607.596901] ============================= [ 607.596906] WARNING: suspicious RCU usage [ 607.596912] 4.13.0-rc4+ #570 Not tainted [ 607.596917] ----------------------------- [ 607.596923] net/core/dev.c:3948 suspicious rcu_dereference_check() usage! [ 607.596927] [ 607.596927] other info that might help us debug this: [ 607.596927] [ 607.596933] [ 607.596933] rcu_scheduler_active = 2, debug_locks = 1 [ 607.596938] 2 locks held by pool/14624: [ 607.596943] #0: (rcu_read_lock_bh){......}, at: [<ffffffff95445ffd>] ip_finish_output2+0x14d/0x890 [ 607.596973] #1: (rcu_read_lock_bh){......}, at: [<ffffffff953c8e3a>] __dev_queue_xmit+0x14a/0xfd0 [ 607.597000] [ 607.597000] stack backtrace: [ 607.597006] CPU: 5 PID: 14624 Comm: pool Not tainted 4.13.0-rc4+ #570 [ 607.597011] Hardware name: Dell Inc. Precision Tower 5810/0HHV7N, BIOS A17 03/01/2017 [ 607.597016] Call Trace: [ 607.597027] dump_stack+0x67/0x92 [ 607.597040] lockdep_rcu_suspicious+0xdd/0x110 [ 607.597054] do_xdp_generic+0x313/0xa50 [ 607.597068] ? time_hardirqs_on+0x5b/0x150 [ 607.597076] ? mark_held_locks+0x6b/0xc0 [ 607.597088] ? netdev_pick_tx+0x150/0x150 [ 607.597117] netif_rx_internal+0x205/0x3f0 [ 607.597127] ? do_xdp_generic+0xa50/0xa50 [ 607.597144] ? lock_downgrade+0x2b0/0x2b0 [ 607.597158] ? __lock_is_held+0x93/0x100 [ 607.597187] netif_rx+0x119/0x190 [ 607.597202] loopback_xmit+0xfd/0x1b0 [ 607.597214] dev_hard_start_xmit+0x127/0x4e0 Fixes: d445516966dc ("net: xdp: support xdp generic on virtual devices") Fixes: b5cdae3291f7 ("net: Generic XDP") Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * bpf: don't select potentially stale ri->map from buggy xdp progsDaniel Borkmann2017-09-081-2/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can potentially run into a couple of issues with the XDP bpf_redirect_map() helper. The ri->map in the per CPU storage can become stale in several ways, mostly due to misuse, where we can then trigger a use after free on the map: i) prog A is calling bpf_redirect_map(), returning XDP_REDIRECT and running on a driver not supporting XDP_REDIRECT yet. The ri->map on that CPU becomes stale when the XDP program is unloaded on the driver, and a prog B loaded on a different driver which supports XDP_REDIRECT return code. prog B would have to omit calling to bpf_redirect_map() and just return XDP_REDIRECT, which would then access the freed map in xdp_do_redirect() since not cleared for that CPU. ii) prog A is calling bpf_redirect_map(), returning a code other than XDP_REDIRECT. prog A is then detached, which triggers release of the map. prog B is attached which, similarly as in i), would just return XDP_REDIRECT without having called bpf_redirect_map() and thus be accessing the freed map in xdp_do_redirect() since not cleared for that CPU. iii) prog A is attached to generic XDP, calling the bpf_redirect_map() helper and returning XDP_REDIRECT. xdp_do_generic_redirect() is currently not handling ri->map (will be fixed by Jesper), so it's not being reset. Later loading a e.g. native prog B which would, say, call bpf_xdp_redirect() and then returns XDP_REDIRECT would find in xdp_do_redirect() that a map was set and uses that causing use after free on map access. Fix thus needs to avoid accessing stale ri->map pointers, naive way would be to call a BPF function from drivers that just resets it to NULL for all XDP return codes but XDP_REDIRECT and including XDP_REDIRECT for drivers not supporting it yet (and let ri->map being handled in xdp_do_generic_redirect()). There is a less intrusive way w/o letting drivers call a reset for each BPF run. The verifier knows we're calling into bpf_xdp_redirect_map() helper, so it can do a small insn rewrite transparent to the prog itself in the sense that it fills R4 with a pointer to the own bpf_prog. We have that pointer at verification time anyway and R4 is allowed to be used as per calling convention we scratch R0 to R5 anyway, so they become inaccessible and program cannot read them prior to a write. Then, the helper would store the prog pointer in the current CPUs struct redirect_info. Later in xdp_do_*_redirect() we check whether the redirect_info's prog pointer is the same as passed xdp_prog pointer, and if that's the case then all good, since the prog holds a ref on the map anyway, so it is always valid at that point in time and must have a reference count of at least 1. If in the unlikely case they are not equal, it means we got a stale pointer, so we clear and bail out right there. Also do reset map and the owning prog in bpf_xdp_redirect(), so that bpf_xdp_redirect_map() and bpf_xdp_redirect() won't get mixed up, only the last call should take precedence. A tc bpf_redirect() doesn't use map anywhere yet, so no need to clear it there since never accessed in that layer. Note that in case the prog is released, and thus the map as well we're still under RCU read critical section at that time and have preemption disabled as well. Once we commit with the __dev_map_insert_ctx() from xdp_do_redirect_map() and set the map to ri->map_to_flush, we still wait for a xdp_do_flush_map() to finish in devmap dismantle time once flush_needed bit is set, so that is fine. Fixes: 97f91a7cf04f ("bpf: add bpf_redirect_map helper routine") Reported-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * udp: drop head states only when all skb references are gonePaolo Abeni2017-09-071-6/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit 0ddf3fb2c43d ("udp: preserve skb->dst if required for IP options processing") we clear the skb head state as soon as the skb carrying them is first processed. Since the same skb can be processed several times when MSG_PEEK is used, we can end up lacking the required head states, and eventually oopsing. Fix this clearing the skb head state only when processing the last skb reference. Reported-by: Eric Dumazet <edumazet@google.com> Fixes: 0ddf3fb2c43d ("udp: preserve skb->dst if required for IP options processing") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge branch 'for-4.14' of ↵Linus Torvalds2017-09-061-1/+1
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: "Several notable changes this cycle: - Thread mode was merged. This will be used for cgroup2 support for CPU and possibly other controllers. Unfortunately, CPU controller cgroup2 support didn't make this pull request but most contentions have been resolved and the support is likely to be merged before the next merge window. - cgroup.stat now shows the number of descendant cgroups. - cpuset now can enable the easier-to-configure v2 behavior on v1 hierarchy" * 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (21 commits) cpuset: Allow v2 behavior in v1 cgroup cgroup: Add mount flag to enable cpuset to use v2 behavior in v1 cgroup cgroup: remove unneeded checks cgroup: misc changes cgroup: short-circuit cset_cgroup_from_root() on the default hierarchy cgroup: re-use the parent pointer in cgroup_destroy_locked() cgroup: add cgroup.stat interface with basic hierarchy stats cgroup: implement hierarchy limits cgroup: keep track of number of descent cgroups cgroup: add comment to cgroup_enable_threaded() cgroup: remove unnecessary empty check when enabling threaded mode cgroup: update debug controller to print out thread mode information cgroup: implement cgroup v2 thread support cgroup: implement CSS_TASK_ITER_THREADED cgroup: introduce cgroup->dom_cgrp and threaded css_set handling cgroup: add @flags to css_task_iter_start() and implement CSS_TASK_ITER_PROCS cgroup: reorganize cgroup.procs / task write path cgroup: replace css_set walking populated test with testing cgrp->nr_populated_csets cgroup: distinguish local and children populated states cgroup: remove now unused list_head @pending in cgroup_apply_cftypes() ...
| * cgroup: add @flags to css_task_iter_start() and implement CSS_TASK_ITER_PROCSTejun Heo2017-07-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | css_task_iter currently always walks all tasks. With the scheduled cgroup v2 thread support, the iterator would need to handle multiple types of iteration. As a preparation, add @flags to css_task_iter_start() and implement CSS_TASK_ITER_PROCS. If the flag is not specified, it walks all tasks as before. When asserted, the iterator only walks the group leaders. For now, the only user of the flag is cgroup v2 "cgroup.procs" file which no longer needs to skip non-leader tasks in cgroup_procs_next(). Note that cgroup v1 "cgroup.procs" can't use the group leader walk as v1 "cgroup.procs" doesn't mean "list all thread group leaders in the cgroup" but "list all thread group id's with any threads in the cgroup". While at it, update cgroup_procs_show() to use task_pid_vnr() instead of task_tgid_vnr(). As the iteration guarantees that the function only sees group leaders, this doesn't change the output and will allow sharing the function for thread iteration. Signed-off-by: Tejun Heo <tj@kernel.org>
* | flow_dissector: Add limit for number of headers to dissectTom Herbert2017-09-051-3/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In flow dissector there are no limits to the number of nested encapsulations or headers that might be dissected which makes for a nice DOS attack. This patch sets a limit of the number of headers that flow dissector will parse. Headers includes network layer headers, transport layer headers, shim headers for encapsulation, IPv6 extension headers, etc. The limit for maximum number of headers to parse has be set to fifteen to account for a reasonable number of encapsulations, extension headers, VLAN, in a packet. Note that this limit does not supercede the STOP_AT_* flags which may stop processing before the headers limit is reached. Reported-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Tom Herbert <tom@quantonium.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | flow_dissector: Cleanup control flowTom Herbert2017-09-051-78/+145
| | | | | | | | | | | | | | | | | | | | | | | | | | __skb_flow_dissect is riddled with gotos that make discerning the flow, debugging, and extending the capability difficult. This patch reorganizes things so that we only perform goto's after the two main switch statements (no gotos within the cases now). It also eliminates several goto labels so that there are only two labels that can be target for goto. Reported-by: Alexander Popov <alex.popov@linux.com> Signed-off-by: Tom Herbert <tom@quantonium.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: Add module reference to FIB notifiersIdo Schimmel2017-09-011-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a listener registers to the FIB notification chain it receives a dump of the FIB entries and rules from existing address families by invoking their dump operations. While we call into these modules we need to make sure they aren't removed. Do that by increasing their reference count before invoking their dump operations and decrease it afterwards. Fixes: 04b1d4e50e82 ("net: core: Make the FIB notification chain generic") Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: convert (struct ubuf_info)->refcnt to refcount_tEric Dumazet2017-09-011-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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. v2: added the change in drivers/vhost/net.c as spotted by Willem. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: prepare (struct ubuf_info)->refcnt conversionEric Dumazet2017-09-011-8/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to convert this atomic_t refcnt to refcount_t, we need to init the refcount to one to not trigger a 0 -> 1 transition. This also removes one atomic operation in fast path. v2: removed dead code in sock_zerocopy_put_abort() as suggested by Willem. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2017-09-014-13/+14
|\ \ | | | | | | | | | | | | | | | Three cases of simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
| * | mlxsw: spectrum: Forbid linking to devices that have uppersIdo Schimmel2017-09-011-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The mlxsw driver relies on NETDEV_CHANGEUPPER events to configure the device in case a port is enslaved to a master netdev such as bridge or bond. Since the driver ignores events unrelated to its ports and their uppers, it's possible to engineer situations in which the device's data path differs from the kernel's. One example to such a situation is when a port is enslaved to a bond that is already enslaved to a bridge. When the bond was enslaved the driver ignored the event - as the bond wasn't one of its uppers - and therefore a bridge port instance isn't created in the device. Until such configurations are supported forbid them by checking that the upper device doesn't have uppers of its own. Fixes: 0d65fc13042f ("mlxsw: spectrum: Implement LAG port join/leave") Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reported-by: Nogah Frankel <nogahf@mellanox.com> Tested-by: Nogah Frankel <nogahf@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | net: missing call of trace_napi_poll in busy_poll_stopJesper Dangaard Brouer2017-08-281-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | Noticed that busy_poll_stop() also invoke the drivers napi->poll() function pointer, but didn't have an associated call to trace_napi_poll() like all other call sites. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | tcp: fix refcnt leak with ebpf congestion controlSabrina Dubroca2017-08-251-5/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are a few bugs around refcnt handling in the new BPF congestion control setsockopt: - The new ca is assigned to icsk->icsk_ca_ops even in the case where we cannot get a reference on it. This would lead to a use after free, since that ca is going away soon. - Changing the congestion control case doesn't release the refcnt on the previous ca. - In the reinit case, we first leak a reference on the old ca, then we call tcp_reinit_congestion_control on the ca that we have just assigned, leading to deinitializing the wrong ca (->release of the new ca on the old ca's data) and releasing the refcount on the ca that we actually want to use. This is visible by building (for example) BIC as a module and setting net.ipv4.tcp_congestion_control=bic, and using tcp_cong_kern.c from samples/bpf. This patch fixes the refcount issues, and moves reinit back into tcp core to avoid passing a ca pointer back to BPF. Fixes: 91b5b21c7c16 ("bpf: Add support for changing congestion control") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | bpf: fix bpf_setsockopts return valueYuchung Cheng2017-08-241-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes a bug causing any sock operations to always return EINVAL. Fixes: a5192c52377e ("bpf: fix to bpf_setsockops"). Reported-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Craig Gallek <kraig@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | net: core: Specify skb_pad()/skb_put_padto() SKB freeingFlorian Fainelli2017-08-231-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename skb_pad() into __skb_pad() and make it take a third argument: free_on_error which controls whether kfree_skb() should be called or not, skb_pad() directly makes use of it and passes true to preserve its existing behavior. Do exactly the same thing with __skb_put_padto() and skb_put_padto(). Suggested-by: David Miller <davem@davemloft.net> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Woojung Huh <Woojung.Huh@microchip.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | udp: on peeking bad csum, drop packets even if not at headEric Dumazet2017-08-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When peeking, if a bad csum is discovered, the skb is unlinked from the queue with __sk_queue_drop_skb and the peek operation restarted. __sk_queue_drop_skb only drops packets that match the queue head. This fails if the skb was found after the head, using SO_PEEK_OFF socket option. This causes an infinite loop. We MUST drop this problematic skb, and we can simply check if skb was already removed by another thread, by looking at skb->next : This pointer is set to NULL by the __skb_unlink() operation, that might have happened only under the spinlock protection. Many thanks to syzkaller team (and particularly Dmitry Vyukov who provided us nice C reproducers exhibiting the lockup) and Willem de Bruijn who provided first version for this patch and a test program. Fixes: 627d2d6b5500 ("udp: enable MSG_PEEK at non-zero offset") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Willem de Bruijn <willemb@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | bpf: Collapse offset checks in sock_filter_is_valid_accessDavid Ahern2017-09-011-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make sock_filter_is_valid_access consistent with other is_valid_access helpers. Requested-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David Ahern <dsahern@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | bpf: Allow cgroup sock filters to use get_current_uid_gid helperDavid Ahern2017-09-011-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow BPF programs run on sock create to use the get_current_uid_gid helper. IPv4 and IPv6 sockets are created in a process context so there is always a valid uid/gid Signed-off-by: David Ahern <dsahern@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | bpf: Add mark and priority to sock options that can be setDavid Ahern2017-09-011-0/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add socket mark and priority to fields that can be set by ebpf program when a socket is created. Signed-off-by: David Ahern <dsahern@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | devlink: Add IPv6 header for dpipeArkadi Sharshevsky2017-08-311-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This will be used by the IPv6 host table which will be introduced in the following patches. The fields in the header are added per-use. This header is global and can be reused by many drivers. Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | bridge: add tracepoint in br_fdb_updateRoopa Prabhu2017-08-311-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This extends bridge fdb table tracepoints to also cover learned fdb entries in the br_fdb_update path. Note that unlike other tracepoints I have moved this to when the fdb is modified because this is in the datapath and can generate a lot of noise in the trace output. br_fdb_update is also called from added_by_user context in the NTF_USE case which is already traced ..hence the !added_by_user check. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | devlink: Maintain consistency in mac field nameDavid Ahern2017-08-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | IPv4 name uses "destination ip" as does the IPv6 patch set. Make the mac field consistent. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | neigh: increase queue_len_bytes to match wmem_defaultEric Dumazet2017-08-291-10/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Florian reported UDP xmit drops that could be root caused to the too small neigh limit. Current limit is 64 KB, meaning that even a single UDP socket would hit it, since its default sk_sndbuf comes from net.core.wmem_default (~212992 bytes on 64bit arches). Once ARP/ND resolution is in progress, we should allow a little more packets to be queued, at least for one producer. Once neigh arp_queue is filled, a rogue socket should hit its sk_sndbuf limit and either block in sendmsg() or return -EAGAIN. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | bridge: fdb add and delete tracepointsRoopa Prabhu2017-08-291-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A few useful tracepoints to trace bridge forwarding database updates. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | xdp: separate xdp_redirect tracepoint in map caseJesper Dangaard Brouer2017-08-291-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Creating as specific xdp_redirect_map variant of the xdp tracepoints allow users to write simpler/faster BPF progs that get attached to these tracepoints. Goal is to still keep the tracepoints in xdp_redirect and xdp_redirect_map similar enough, that a tool can read the top part of the TP_STRUCT and produce similar monitor statistics. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | xdp: separate xdp_redirect tracepoint in error caseJesper Dangaard Brouer2017-08-291-13/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a need to separate the xdp_redirect tracepoint into two tracepoints, for separating the error case from the normal forward case. Due to the extreme speeds XDP is operating at, loading a tracepoint have a measurable impact. Single core XDP REDIRECT (ethtool tuned rx-usecs 25) can do 13.7 Mpps forwarding, but loading a simple bpf_prog at the tracepoint (with a return 0) reduce perf to 10.2 Mpps (CPU E5-1650 v4 @ 3.60GHz, driver: ixgbe) The overhead of loading a bpf-based tracepoint can be calculated to cost 25 nanosec ((1/13782002-1/10267937)*10^9 = -24.83 ns). Using perf record on the tracepoint event, with a non-matching --filter expression, the overhead is much larger. Performance drops to 8.3 Mpps, cost 48 nanosec ((1/13782002-1/8312497)*10^9 = -47.74)) Having a separate tracepoint for err cases, which should be less frequent, allow running a continuous monitor for errors while not affecting the redirect forward performance (this have also been verified by measurements). Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | xdp: tracepoint xdp_redirect also need a map argumentJesper Dangaard Brouer2017-08-291-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To make sense of the map index, the tracepoint user also need to know that map we are talking about. Supply the map pointer but only expose the map->id. The 'to_index' is renamed 'to_ifindex'. In the xdp_redirect_map case, this is the result of the devmap lookup. The map lookup key is exposed as map_index, which is needed to troubleshoot in case the lookup failed. The 'to_ifindex' is placed after 'err' to keep TP_STRUCT as common as possible. This also keeps the TP_STRUCT similar enough, that userspace can write a monitor program, that doesn't need to care about whether bpf_redirect or bpf_redirect_map were used. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | xdp: remove redundant argument to trace_xdp_redirectJesper Dangaard Brouer2017-08-291-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Supplying the action argument XDP_REDIRECT to the tracepoint xdp_redirect is redundant as it is only called in-case this action was specified. Remove the argument, but keep "act" member of the tracepoint struct and populate it with XDP_REDIRECT. This makes it easier to write a common bpf_prog processing events. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | xdp: remove net_device names from xdp_redirect tracepointJesper Dangaard Brouer2017-08-241-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is too much overhead in the current trace_xdp_redirect tracepoint as it does strcpy and strlen on the net_device names. Besides, exposing the ifindex/index is actually the information that is needed in the tracepoint to diagnose issues. When a lookup fails (either ifindex or devmap index) then there is a need for saying which to_index that have issues. V2: Adjust args to be aligned with trace_xdp_exception. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | xdp: make generic xdp redirect use tracepoint trace_xdp_redirectJesper Dangaard Brouer2017-08-242-14/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the xdp_do_generic_redirect() call fails, it trigger the trace_xdp_exception tracepoint. It seems better to use the same tracepoint trace_xdp_redirect, as the native xdp_do_redirect{,_map} does. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | xdp: remove bpf_warn_invalid_xdp_redirectJesper Dangaard Brouer2017-08-241-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Given there is a tracepoint that can track the error code of xdp_do_redirect calls, the WARN_ONCE in bpf_warn_invalid_xdp_redirect doesn't seem relevant any longer. Simply remove the function. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | devlink: Move dpipe entry clear function into devlinkArkadi Sharshevsky2017-08-241-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | The entry clear routine can be shared between the drivers, thus it is moved inside devlink. Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | devlink: Add support for dynamic table sizeArkadi Sharshevsky2017-08-241-5/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Up until now the dpipe table's size was static and known at registration time. The host table does not have constant size and it is resized in dynamic manner. In order to support this behavior the size is changed to be obtained dynamically via an op. This patch also adjust the current dpipe table for the new API. Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | devlink: Add IPv4 header for dpipeArkadi Sharshevsky2017-08-241-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This will be used by the IPv4 host table which will be introduced in the following patches. This header is global and can be reused by many drivers. Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | devlink: Add Ethernet header for dpipeArkadi Sharshevsky2017-08-241-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This will be used by the IPv4 host table which will be introduced in the following patches. This header is global and can be reused by many drivers. Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net/sock: allow the user to set negative peek offsetPaolo Abeni2017-08-231-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is necessary to allow the user to disable peeking with offset once it's enabled. Unix sockets already allow the above, with this patch we permit it for udp[6] sockets, too. Fixes: 627d2d6b5500 ("udp: enable MSG_PEEK at non-zero offset") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | bpf: misc xdp redirect cleanupsDaniel Borkmann2017-08-221-40/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Few cleanups including: bpf_redirect_map() is really XDP only due to the return code. Move it to a more appropriate location where we do the XDP redirect handling and change it's name into bpf_xdp_redirect_map() to make it consistent to the bpf_xdp_redirect() helper. xdp_do_redirect_map() helper can be static since only used out of filter.c file. Drop the goto in xdp_do_generic_redirect() and only return errors directly. In xdp_do_flush_map() only clear ri->map_to_flush which is the arg we're using in that function, ri->map is cleared earlier along with ri->ifindex. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2017-08-211-3/+9
|\| |
| * | datagram: When peeking datagrams with offset < 0 don't skip empty skbsMatthew Dawson2017-08-181-3/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Due to commit e6afc8ace6dd5cef5e812f26c72579da8806f5ac ("udp: remove headers from UDP packets before queueing"), when udp packets are being peeked the requested extra offset is always 0 as there is no need to skip the udp header. However, when the offset is 0 and the next skb is of length 0, it is only returned once. The behaviour can be seen with the following python script: from socket import *; f=socket(AF_INET6, SOCK_DGRAM | SOCK_NONBLOCK, 0); g=socket(AF_INET6, SOCK_DGRAM | SOCK_NONBLOCK, 0); f.bind(('::', 0)); addr=('::1', f.getsockname()[1]); g.sendto(b'', addr) g.sendto(b'b', addr) print(f.recvfrom(10, MSG_PEEK)); print(f.recvfrom(10, MSG_PEEK)); Where the expected output should be the empty string twice. Instead, make sk_peek_offset return negative values, and pass those values to __skb_try_recv_datagram/__skb_try_recv_from_queue. If the passed offset to __skb_try_recv_from_queue is negative, the checked skb is never skipped. __skb_try_recv_from_queue will then ensure the offset is reset back to 0 if a peek is requested without an offset, unless no packets are found. Also simplify the if condition in __skb_try_recv_from_queue. If _off is greater then 0, and off is greater then or equal to skb->len, then (_off || skb->len) must always be true assuming skb->len >= 0 is always true. Also remove a redundant check around a call to sk_peek_offset in af_unix.c, as it double checked if MSG_PEEK was set in the flags. V2: - Moved the negative fixup into __skb_try_recv_from_queue, and remove now redundant checks - Fix peeking in udp{,v6}_recvmsg to report the right value when the offset is 0 V3: - Marked new branch in __skb_try_recv_from_queue as unlikely. Signed-off-by: Matthew Dawson <matthew@mjdsystems.ca> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | net: check type when freeing metadata dstDavid Lamparter2017-08-211-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 3fcece12bc1b ("net: store port/representator id in metadata_dst") added a new type field to metadata_dst, but metadata_dst_free() wasn't updated to check it before freeing the METADATA_IP_TUNNEL specific dst cache entry. This is not currently causing problems since it's far enough back in the struct to be zeroed for the only other type currently in existance (METADATA_HW_PORT_MUX), but nevertheless it's not correct. Fixes: 3fcece12bc1b ("net: store port/representator id in metadata_dst") Signed-off-by: David Lamparter <equinox@diac24.net> Cc: Jakub Kicinski <jakub.kicinski@netronome.com> Cc: Sridhar Samudrala <sridhar.samudrala@intel.com> Cc: Simon Horman <horms@verge.net.au> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | Merge branch 'master' of ↵David S. Miller2017-08-211-1/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next Steffen Klassert says: ==================== pull request (net-next): ipsec-next 2017-08-21 1) Support RX checksum with IPsec crypto offload for esp4/esp6. From Ilan Tayari. 2) Fixup IPv6 checksums when doing IPsec crypto offload. From Yossi Kuperman. 3) Auto load the xfrom offload modules if a user installs a SA that requests IPsec offload. From Ilan Tayari. 4) Clear RX offload informations in xfrm_input to not confuse the TX path with stale offload informations. From Ilan Tayari. 5) Allow IPsec GSO for local sockets if the crypto operation will be offloaded. 6) Support setting of an output mark to the xfrm_state. This mark can be used to to do the tunnel route lookup. From Lorenzo Colitti. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>