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2023-10-19net: move altnames together with the netdeviceJakub Kicinski1-4/+9
The altname nodes are currently not moved to the new netns when netdevice itself moves: [ ~]# ip netns add test [ ~]# ip -netns test link add name eth0 type dummy [ ~]# ip -netns test link property add dev eth0 altname some-name [ ~]# ip -netns test link show dev some-name 2: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 1e:67:ed:19:3d:24 brd ff:ff:ff:ff:ff:ff altname some-name [ ~]# ip -netns test link set dev eth0 netns 1 [ ~]# ip link ... 3: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 02:40:88:62:ec:b8 brd ff:ff:ff:ff:ff:ff altname some-name [ ~]# ip li show dev some-name Device "some-name" does not exist. Remove them from the hash table when device is unlisted and add back when listed again. Fixes: 36fbf1e52bd3 ("net: rtnetlink: add linkprop commands to add and delete alternative ifnames") Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-10-19net: avoid UAF on deleted altnameJakub Kicinski1-1/+6
Altnames are accessed under RCU (dev_get_by_name_rcu()) but freed by kfree() with no synchronization point. Each node has one or two allocations (node and a variable-size name, sometimes the name is netdev->name). Adding rcu_heads here is a bit tedious. Besides most code which unlists the names already has rcu barriers - so take the simpler approach of adding synchronize_rcu(). Note that the one on the unregistration path (which matters more) is removed by the next fix. Fixes: ff92741270bf ("net: introduce name_node struct to be used in hashlist") Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-10-19net: check for altname conflicts when changing netdev's netnsJakub Kicinski1-1/+8
It's currently possible to create an altname conflicting with an altname or real name of another device by creating it in another netns and moving it over: [ ~]$ ip link add dev eth0 type dummy [ ~]$ ip netns add test [ ~]$ ip -netns test link add dev ethX netns test type dummy [ ~]$ ip -netns test link property add dev ethX altname eth0 [ ~]$ ip -netns test link set dev ethX netns 1 [ ~]$ ip link ... 3: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 02:40:88:62:ec:b8 brd ff:ff:ff:ff:ff:ff ... 5: ethX: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 26:b7:28:78:38:0f brd ff:ff:ff:ff:ff:ff altname eth0 Create a macro for walking the altnames, this hopefully makes it clearer that the list we walk contains only altnames. Which is otherwise not entirely intuitive. Fixes: 36fbf1e52bd3 ("net: rtnetlink: add linkprop commands to add and delete alternative ifnames") Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-10-19net: fix ifname in netlink ntf during netns moveJakub Kicinski1-13/+31
dev_get_valid_name() overwrites the netdev's name on success. This makes it hard to use in prepare-commit-like fashion, where we do validation first, and "commit" to the change later. Factor out a helper which lets us save the new name to a buffer. Use it to fix the problem of notification on netns move having incorrect name: 5: eth0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN group default link/ether be:4d:58:f9:d5:40 brd ff:ff:ff:ff:ff:ff 6: eth1: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN group default link/ether 1e:4a:34:36:e3:cd brd ff:ff:ff:ff:ff:ff [ ~]# ip link set dev eth0 netns 1 name eth1 ip monitor inside netns: Deleted inet eth0 Deleted inet6 eth0 Deleted 5: eth1: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN group default link/ether be:4d:58:f9:d5:40 brd ff:ff:ff:ff:ff:ff new-netnsid 0 new-ifindex 7 Name is reported as eth1 in old netns for ifindex 5, already renamed. Fixes: d90310243fd7 ("net: device name allocation cleanups") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-10-10net: refine debug info in skb_checksum_help()Eric Dumazet1-2/+6
syzbot uses panic_on_warn. This means that the skb_dump() I added in the blamed commit are not even called. Rewrite this so that we get the needed skb dump before syzbot crashes. Fixes: eeee4b77dc52 ("net: add more debug info in skb_checksum_help()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20231006173355.2254983-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-09-16net: core: Use the bitmap API to allocate bitmapsAndy Shevchenko1-3/+3
Use bitmap_zalloc() and bitmap_free() instead of hand-writing them. It is less verbose and it improves the type checking and semantic. While at it, add missing header inclusion (should be bitops.h, but with the above change it becomes bitmap.h). Suggested-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/20230911154534.4174265-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-28net: Make consumed action consistent in sch_handle_egressDaniel Borkmann1-0/+2
While looking at TC_ACT_* handling, the TC_ACT_CONSUMED is only handled in sch_handle_ingress but not sch_handle_egress. This was added via cd11b164073b ("net/tc: introduce TC_ACT_REINSERT.") and e5cf1baf92cb ("act_mirred: use TC_ACT_REINSERT when possible") and later got renamed into TC_ACT_CONSUMED via 720f22fed81b ("net: sched: refactor reinsert action"). The initial work was targeted for ovs back then and only needed on ingress, and the mirred action module also restricts it to only that. However, given it's an API contract it would still make sense to make this consistent to sch_handle_ingress and handle it on egress side in the same way, that is, setting return code to "success" and returning NULL back to the caller as otherwise an action module sitting on egress returning TC_ACT_CONSUMED could lead to an UAF when untreated. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-28net: Fix skb consume leak in sch_handle_egressDaniel Borkmann1-0/+1
Fix a memory leak for the tc egress path with TC_ACT_{STOLEN,QUEUED,TRAP}: [...] unreferenced object 0xffff88818bcb4f00 (size 232): comm "softirq", pid 0, jiffies 4299085078 (age 134.028s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 80 70 61 81 88 ff ff 00 41 31 14 81 88 ff ff ..pa.....A1..... backtrace: [<ffffffff9991b938>] kmem_cache_alloc_node+0x268/0x400 [<ffffffff9b3d9231>] __alloc_skb+0x211/0x2c0 [<ffffffff9b3f0c7e>] alloc_skb_with_frags+0xbe/0x6b0 [<ffffffff9b3bf9a9>] sock_alloc_send_pskb+0x6a9/0x870 [<ffffffff9b6b3f00>] __ip_append_data+0x14d0/0x3bf0 [<ffffffff9b6ba24e>] ip_append_data+0xee/0x190 [<ffffffff9b7e1496>] icmp_push_reply+0xa6/0x470 [<ffffffff9b7e4030>] icmp_reply+0x900/0xa00 [<ffffffff9b7e42e3>] icmp_echo.part.0+0x1a3/0x230 [<ffffffff9b7e444d>] icmp_echo+0xcd/0x190 [<ffffffff9b7e9566>] icmp_rcv+0x806/0xe10 [<ffffffff9b699bd1>] ip_protocol_deliver_rcu+0x351/0x3d0 [<ffffffff9b699f14>] ip_local_deliver_finish+0x2b4/0x450 [<ffffffff9b69a234>] ip_local_deliver+0x174/0x1f0 [<ffffffff9b69a4b2>] ip_sublist_rcv_finish+0x1f2/0x420 [<ffffffff9b69ab56>] ip_sublist_rcv+0x466/0x920 [...] I was able to reproduce this via: ip link add dev dummy0 type dummy ip link set dev dummy0 up tc qdisc add dev eth0 clsact tc filter add dev eth0 egress protocol ip prio 1 u32 match ip protocol 1 0xff action mirred egress redirect dev dummy0 ping 1.1.1.1 <stolen> After the fix, there are no kmemleak reports with the reproducer. This is in line with what is also done on the ingress side, and from debugging the skb_unref(skb) on dummy xmit and sch_handle_egress() side, it is visible that these are two different skbs with both skb_unref(skb) as true. The two seen skbs are due to mirred doing a skb_clone() internally as use_reinsert is false in tcf_mirred_act() for egress. This was initially reported by Gal. Fixes: e420bed02507 ("bpf: Add fd-based tcx multi-prog infra with link support") Reported-by: Gal Pressman <gal@nvidia.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/bdfc2640-8f65-5b56-4472-db8e2b161aab@nvidia.com Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-16net: warn about attempts to register negative ifindexJakub Kicinski1-0/+5
Since the xarray changes we mix returning valid ifindex and negative errno in a single int returned from dev_index_reserve(). This depends on the fact that ifindexes can't be negative. Otherwise we may insert into the xarray and return a very large negative value. This in turn may break ERR_PTR(). OvS is susceptible to this problem and lacking validation (fix posted separately for net). Reject negative ifindex explicitly. Add a warning because the input validation is better handled by the caller. Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Link: https://lore.kernel.org/r/20230814205627.2914583-2-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-04Merge tag 'for-netdev' of ↵Jakub Kicinski1-1/+5
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Martin KaFai Lau says: ==================== pull-request: bpf-next 2023-08-03 We've added 54 non-merge commits during the last 10 day(s) which contain a total of 84 files changed, 4026 insertions(+), 562 deletions(-). The main changes are: 1) Add SO_REUSEPORT support for TC bpf_sk_assign from Lorenz Bauer, Daniel Borkmann 2) Support new insns from cpu v4 from Yonghong Song 3) Non-atomically allocate freelist during prefill from YiFei Zhu 4) Support defragmenting IPv(4|6) packets in BPF from Daniel Xu 5) Add tracepoint to xdp attaching failure from Leon Hwang 6) struct netdev_rx_queue and xdp.h reshuffling to reduce rebuild time from Jakub Kicinski * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (54 commits) net: invert the netdevice.h vs xdp.h dependency net: move struct netdev_rx_queue out of netdevice.h eth: add missing xdp.h includes in drivers selftests/bpf: Add testcase for xdp attaching failure tracepoint bpf, xdp: Add tracepoint to xdp attaching failure selftests/bpf: fix static assert compilation issue for test_cls_*.c bpf: fix bpf_probe_read_kernel prototype mismatch riscv, bpf: Adapt bpf trampoline to optimized riscv ftrace framework libbpf: fix typos in Makefile tracing: bpf: use struct trace_entry in struct syscall_tp_t bpf, devmap: Remove unused dtab field from bpf_dtab_netdev bpf, cpumap: Remove unused cmap field from bpf_cpu_map_entry netfilter: bpf: Only define get_proto_defrag_hook() if necessary bpf: Fix an array-index-out-of-bounds issue in disasm.c net: remove duplicate INDIRECT_CALLABLE_DECLARE of udp[6]_ehashfn docs/bpf: Fix malformed documentation bpf: selftests: Add defrag selftests bpf: selftests: Support custom type and proto for client sockets bpf: selftests: Support not connecting client socket netfilter: bpf: Support BPF_F_NETFILTER_IP_DEFRAG in netfilter link ... ==================== Link: https://lore.kernel.org/r/20230803174845.825419-1-martin.lau@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-03net: move struct netdev_rx_queue out of netdevice.hJakub Kicinski1-0/+1
struct netdev_rx_queue is touched in only a few places and having it defined in netdevice.h brings in the dependency on xdp.h, because struct xdp_rxq_info gets embedded in struct netdev_rx_queue. In prep for removal of xdp.h from netdevice.h move all the netdev_rx_queue stuff to a new header. We could technically break the new header up to avoid the sysfs.h include but it's so rarely included it doesn't seem to be worth it at this point. Reviewed-by: Amritha Nambiar <amritha.nambiar@intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Link: https://lore.kernel.org/r/20230803010230.1755386-3-kuba@kernel.org Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-08-03bpf, xdp: Add tracepoint to xdp attaching failureLeon Hwang1-1/+4
When error happens in dev_xdp_attach(), it should have a way to tell users the error message like the netlink approach. To avoid breaking uapi, adding a tracepoint in bpf_xdp_link_attach() is an appropriate way to notify users the error message. Hence, bpf libraries are able to retrieve the error message by this tracepoint, and then report the error message to users. Signed-off-by: Leon Hwang <hffilwlqm@gmail.com> Link: https://lore.kernel.org/r/20230801142621.7925-2-hffilwlqm@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-08-02net: make sure we never create ifindex = 0Jakub Kicinski1-2/+1
Instead of allocating from 1 use proper xa_init flag, to protect ourselves from IDs wrapping back to 0. Fixes: 759ab1edb56c ("net: store netdevs in an xarray") Reported-by: Stephen Hemminger <stephen@networkplumber.org> Link: https://lore.kernel.org/all/20230728162350.2a6d4979@hermes.local/ Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Link: https://lore.kernel.org/r/20230731171159.988962-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-28net: store netdevs in an xarrayJakub Kicinski1-28/+54
Iterating over the netdev hash table for netlink dumps is hard. Dumps are done in "chunks" so we need to save the position after each chunk, so we know where to restart from. Because netdevs are stored in a hash table we remember which bucket we were in and how many devices we dumped. Since we don't hold any locks across the "chunks" - devices may come and go while we're dumping. If that happens we may miss a device (if device is deleted from the bucket we were in). We indicate to user space that this may have happened by setting NLM_F_DUMP_INTR. User space is supposed to dump again (I think) if it sees that. Somehow I doubt most user space gets this right.. To illustrate let's look at an example: System state: start: # [A, B, C] del: B # [A, C] with the hash table we may dump [A, B], missing C completely even tho it existed both before and after the "del B". Add an xarray and use it to allocate ifindexes. This way we can iterate ifindexes in order, without the worry that we'll skip one. We may still generate a dump of a state which "never existed", for example for a set of values and sequence of ops: System state: start: # [A, B] add: C # [A, C, B] del: B # [A, C] we may generate a dump of [A], if C got an index between A and B. System has never been in such state. But I'm 90% sure that's perfectly fine, important part is that we can't _miss_ devices which exist before and after. User space which wants to mirror kernel's state subscribes to notifications and does periodic dumps so it will know that C exists from the notification about its creation or from the next dump (next dump is _guaranteed_ to include C, if it doesn't get removed). To avoid any perf regressions keep the hash table for now. Most net namespaces have very few devices and microbenchmarking 1M lookups on Skylake I get the following results (not counting loopback to number of devs): #devs | hash | xa | delta 2 | 18.3 | 20.1 | + 9.8% 16 | 18.3 | 20.1 | + 9.5% 64 | 18.3 | 26.3 | +43.8% 128 | 20.4 | 26.3 | +28.6% 256 | 20.0 | 26.4 | +32.1% 1024 | 26.6 | 26.7 | + 0.2% 8192 |541.3 | 33.5 | -93.8% No surprises since the hash table has 256 entries. The microbenchmark scans indexes in order, if the pattern is more random xa starts to win at 512 devices already. But that's a lot of devices, in practice. Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Link: https://lore.kernel.org/r/20230726185530.2247698-2-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-26net: remove redundant NULL check in remove_xps_queue()Zhengchao Shao1-2/+1
There are currently two paths that call remove_xps_queue(): 1. __netif_set_xps_queue -> remove_xps_queue 2. clean_xps_maps -> remove_xps_queue_cpu -> remove_xps_queue There is no need to check dev_maps in remove_xps_queue() because dev_maps has been checked on these two paths. Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> Link: https://lore.kernel.org/r/20230724023735.2751602-1-shaozhengchao@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-19bpf: Add fd-based tcx multi-prog infra with link supportDaniel Borkmann1-102/+163
This work refactors and adds a lightweight extension ("tcx") to the tc BPF ingress and egress data path side for allowing BPF program management based on fds via bpf() syscall through the newly added generic multi-prog API. The main goal behind this work which we also presented at LPC [0] last year and a recent update at LSF/MM/BPF this year [3] is to support long-awaited BPF link functionality for tc BPF programs, which allows for a model of safe ownership and program detachment. Given the rise in tc BPF users in cloud native environments, this becomes necessary to avoid hard to debug incidents either through stale leftover programs or 3rd party applications accidentally stepping on each others toes. As a recap, a BPF link represents the attachment of a BPF program to a BPF hook point. The BPF link holds a single reference to keep BPF program alive. Moreover, hook points do not reference a BPF link, only the application's fd or pinning does. A BPF link holds meta-data specific to attachment and implements operations for link creation, (atomic) BPF program update, detachment and introspection. The motivation for BPF links for tc BPF programs is multi-fold, for example: - From Meta: "It's especially important for applications that are deployed fleet-wide and that don't "control" hosts they are deployed to. If such application crashes and no one notices and does anything about that, BPF program will keep running draining resources or even just, say, dropping packets. We at FB had outages due to such permanent BPF attachment semantics. With fd-based BPF link we are getting a framework, which allows safe, auto-detachable behavior by default, unless application explicitly opts in by pinning the BPF link." [1] - From Cilium-side the tc BPF programs we attach to host-facing veth devices and phys devices build the core datapath for Kubernetes Pods, and they implement forwarding, load-balancing, policy, EDT-management, etc, within BPF. Currently there is no concept of 'safe' ownership, e.g. we've recently experienced hard-to-debug issues in a user's staging environment where another Kubernetes application using tc BPF attached to the same prio/handle of cls_bpf, accidentally wiping all Cilium-based BPF programs from underneath it. The goal is to establish a clear/safe ownership model via links which cannot accidentally be overridden. [0,2] BPF links for tc can co-exist with non-link attachments, and the semantics are in line also with XDP links: BPF links cannot replace other BPF links, BPF links cannot replace non-BPF links, non-BPF links cannot replace BPF links and lastly only non-BPF links can replace non-BPF links. In case of Cilium, this would solve mentioned issue of safe ownership model as 3rd party applications would not be able to accidentally wipe Cilium programs, even if they are not BPF link aware. Earlier attempts [4] have tried to integrate BPF links into core tc machinery to solve cls_bpf, which has been intrusive to the generic tc kernel API with extensions only specific to cls_bpf and suboptimal/complex since cls_bpf could be wiped from the qdisc also. Locking a tc BPF program in place this way, is getting into layering hacks given the two object models are vastly different. We instead implemented the tcx (tc 'express') layer which is an fd-based tc BPF attach API, so that the BPF link implementation blends in naturally similar to other link types which are fd-based and without the need for changing core tc internal APIs. BPF programs for tc can then be successively migrated from classic cls_bpf to the new tc BPF link without needing to change the program's source code, just the BPF loader mechanics for attaching is sufficient. For the current tc framework, there is no change in behavior with this change and neither does this change touch on tc core kernel APIs. The gist of this patch is that the ingress and egress hook have a lightweight, qdisc-less extension for BPF to attach its tc BPF programs, in other words, a minimal entry point for tc BPF. The name tcx has been suggested from discussion of earlier revisions of this work as a good fit, and to more easily differ between the classic cls_bpf attachment and the fd-based one. For the ingress and egress tcx points, the device holds a cache-friendly array with program pointers which is separated from control plane (slow-path) data. Earlier versions of this work used priority to determine ordering and expression of dependencies similar as with classic tc, but it was challenged that for something more future-proof a better user experience is required. Hence this resulted in the design and development of the generic attach/detach/query API for multi-progs. See prior patch with its discussion on the API design. tcx is the first user and later we plan to integrate also others, for example, one candidate is multi-prog support for XDP which would benefit and have the same 'look and feel' from API perspective. The goal with tcx is to have maximum compatibility to existing tc BPF programs, so they don't need to be rewritten specifically. Compatibility to call into classic tcf_classify() is also provided in order to allow successive migration or both to cleanly co-exist where needed given its all one logical tc layer and the tcx plus classic tc cls/act build one logical overall processing pipeline. tcx supports the simplified return codes TCX_NEXT which is non-terminating (go to next program) and terminating ones with TCX_PASS, TCX_DROP, TCX_REDIRECT. The fd-based API is behind a static key, so that when unused the code is also not entered. The struct tcx_entry's program array is currently static, but could be made dynamic if necessary at a point in future. The a/b pair swap design has been chosen so that for detachment there are no allocations which otherwise could fail. The work has been tested with tc-testing selftest suite which all passes, as well as the tc BPF tests from the BPF CI, and also with Cilium's L4LB. Thanks also to Nikolay Aleksandrov and Martin Lau for in-depth early reviews of this work. [0] https://lpc.events/event/16/contributions/1353/ [1] https://lore.kernel.org/bpf/CAEf4BzbokCJN33Nw_kg82sO=xppXnKWEncGTWCTB9vGCmLB6pw@mail.gmail.com [2] https://colocatedeventseu2023.sched.com/event/1Jo6O/tales-from-an-ebpf-programs-murder-mystery-hemanth-malla-guillaume-fournier-datadog [3] http://vger.kernel.org/bpfconf2023_material/tcx_meta_netdev_borkmann.pdf [4] https://lore.kernel.org/bpf/20210604063116.234316-1-memxor@gmail.com Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/r/20230719140858.13224-3-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-19xsk: add new netlink attribute dedicated for ZC max fragsMaciej Fijalkowski1-0/+1
Introduce new netlink attribute NETDEV_A_DEV_XDP_ZC_MAX_SEGS that will carry maximum fragments that underlying ZC driver is able to handle on TX side. It is going to be included in netlink response only when driver supports ZC. Any value higher than 1 implies multi-buffer ZC support on underlying device. Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Link: https://lore.kernel.org/r/20230719132421.584801-11-maciej.fijalkowski@intel.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-11net/core: Make use of assign_bit() APIAndy Shevchenko1-6/+2
We have for some time the assign_bit() API to replace open coded if (foo) set_bit(n, bar); else clear_bit(n, bar); Use this API in the code. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com> Message-ID: <20230710100830.89936-1-andriy.shevchenko@linux.intel.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-06-23net: fix net device address assign typePiotr Gardocki1-5/+5
Commit ad72c4a06acc introduced optimization to return from function quickly if the MAC address is not changing at all. It was reported that such change causes dev->addr_assign_type to not change to NET_ADDR_SET from _PERM or _RANDOM. Restore the old behavior and skip only call to ndo_set_mac_address. Fixes: ad72c4a06acc ("net: add check for current MAC address in dev_set_mac_address") Reported-by: Gal Pressman <gal@nvidia.com> Signed-off-by: Piotr Gardocki <piotrx.gardocki@intel.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20230621132106.991342-1-piotrx.gardocki@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-16net: add check for current MAC address in dev_set_mac_addressPiotr Gardocki1-0/+2
In some cases it is possible for kernel to come with request to change primary MAC address to the address that is already set on the given interface. Add proper check to return fast from the function in these cases. An example of such case is adding an interface to bonding channel in balance-alb mode: modprobe bonding mode=balance-alb miimon=100 max_bonds=1 ip link set bond0 up ifenslave bond0 <eth> Signed-off-by: Piotr Gardocki <piotrx.gardocki@intel.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-15net: create device lookup API with reference trackingJakub Kicinski1-18/+45
New users of dev_get_by_index() and dev_get_by_name() keep getting added and it would be nice to steer them towards the APIs with reference tracking. Add variants of those calls which allocate the reference tracker and use them in a couple of places. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-06-10net: move gso declarations and functions to their own filesEric Dumazet1-69/+1
Move declarations into include/net/gso.h and code into net/core/gso.c Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Stanislav Fomichev <sdf@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20230608191738.3947077-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-08Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-3/+5
Cross-merge networking fixes after downstream PR. Conflicts: net/sched/sch_taprio.c d636fc5dd692 ("net: sched: add rcu annotations around qdisc->qdisc_sleeping") dced11ef84fb ("net/sched: taprio: don't overwrite "sch" variable in taprio_dump_class_stats()") net/ipv4/sysctl_net_ipv4.c e209fee4118f ("net/ipv4: ping_group_range: allow GID from 2147483648 to 4294967294") ccce324dabfe ("tcp: make the first N SYN RTO backoffs linear") https://lore.kernel.org/all/20230605100816.08d41a7b@canb.auug.org.au/ No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-07net: sched: add rcu annotations around qdisc->qdisc_sleepingEric Dumazet1-1/+1
syzbot reported a race around qdisc->qdisc_sleeping [1] It is time we add proper annotations to reads and writes to/from qdisc->qdisc_sleeping. [1] BUG: KCSAN: data-race in dev_graft_qdisc / qdisc_lookup_rcu read to 0xffff8881286fc618 of 8 bytes by task 6928 on cpu 1: qdisc_lookup_rcu+0x192/0x2c0 net/sched/sch_api.c:331 __tcf_qdisc_find+0x74/0x3c0 net/sched/cls_api.c:1174 tc_get_tfilter+0x18f/0x990 net/sched/cls_api.c:2547 rtnetlink_rcv_msg+0x7af/0x8c0 net/core/rtnetlink.c:6386 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2546 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6413 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x56f/0x640 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x665/0x770 net/netlink/af_netlink.c:1913 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] ____sys_sendmsg+0x375/0x4c0 net/socket.c:2503 ___sys_sendmsg net/socket.c:2557 [inline] __sys_sendmsg+0x1e3/0x270 net/socket.c:2586 __do_sys_sendmsg net/socket.c:2595 [inline] __se_sys_sendmsg net/socket.c:2593 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2593 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd write to 0xffff8881286fc618 of 8 bytes by task 6912 on cpu 0: dev_graft_qdisc+0x4f/0x80 net/sched/sch_generic.c:1115 qdisc_graft+0x7d0/0xb60 net/sched/sch_api.c:1103 tc_modify_qdisc+0x712/0xf10 net/sched/sch_api.c:1693 rtnetlink_rcv_msg+0x807/0x8c0 net/core/rtnetlink.c:6395 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2546 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6413 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x56f/0x640 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x665/0x770 net/netlink/af_netlink.c:1913 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] ____sys_sendmsg+0x375/0x4c0 net/socket.c:2503 ___sys_sendmsg net/socket.c:2557 [inline] __sys_sendmsg+0x1e3/0x270 net/socket.c:2586 __do_sys_sendmsg net/socket.c:2595 [inline] __se_sys_sendmsg net/socket.c:2593 [inline] __x64_sys_sendmsg+0x46/0x50 net/socket.c:2593 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 6912 Comm: syz-executor.5 Not tainted 6.4.0-rc3-syzkaller-00190-g0d85b27b0cc6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/16/2023 Fixes: 3a7d0d07a386 ("net: sched: extend Qdisc with rcu") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Vlad Buslov <vladbu@nvidia.com> Acked-by: Jamal Hadi Salim<jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-06-07rfs: annotate lockless accesses to RFS sock flow tableEric Dumazet1-2/+4
Add READ_ONCE()/WRITE_ONCE() on accesses to the sock flow table. This also prevents a (smart ?) compiler to remove the condition in: if (table->ents[index] != newval) table->ents[index] = newval; We need the condition to avoid dirtying a shared cache line. Fixes: fec5e652e58f ("rfs: Receive Flow Steering") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-06-06Merge branch 'drm-i915-use-ref_tracker-library-for-tracking-wakerefs'Jakub Kicinski1-1/+1
Andrzej Hajda says: ==================== drm/i915: use ref_tracker library for tracking wakerefs This is reviewed series of ref_tracker patches, ready to merge via network tree, rebased on net-next/main. i915 patches will be merged later via intel-gfx tree. ==================== Merge on top of an -rc tag in case it's needed in another tree. Link: https://lore.kernel.org/r/20230224-track_gt-v9-0-5b47a33f55d1@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-06lib/ref_tracker: improve printing statsAndrzej Hajda1-1/+1
In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-01net: don't set sw irq coalescing defaults in case of PREEMPT_RTHeiner Kallweit1-2/+4
If PREEMPT_RT is set, then assume that the user focuses on minimum latency. Therefore don't set sw irq coalescing defaults. This affects the defaults only, users can override these settings via sysfs. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Link: https://lore.kernel.org/r/f9439c7f-c92c-4c2c-703e-110f96d841b7@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-26net/core: Enable socket busy polling on -RTKurt Kanzenbach1-3/+6
Busy polling is currently not allowed on PREEMPT_RT, because it disables preemption while invoking the NAPI callback. It is not possible to acquire sleeping locks with disabled preemption. For details see commit 20ab39d13e2e ("net/core: disable NET_RX_BUSY_POLL on PREEMPT_RT"). However, strict cyclic and/or low latency network applications may prefer busy polling e.g., using AF_XDP instead of interrupt driven communication. The preempt_disable() is used in order to prevent the poll_owner and NAPI owner to be preempted while owning the resource to ensure progress. Netpoll performs busy polling in order to acquire the lock. NAPI is locked by setting the NAPIF_STATE_SCHED flag. There is no busy polling if the flag is set and the "owner" is preempted. Worst case is that the task owning NAPI gets preempted and NAPI processing stalls. This is can be prevented by properly prioritising the tasks within the system. Allow RX_BUSY_POLL on PREEMPT_RT if NETPOLL is disabled. Don't disable preemption on PREEMPT_RT within the busy poll loop. Tested on x86 hardware with v6.1-RT and v6.3-RT on Intel i225 (igc) with AF_XDP/ZC sockets configured to run in busy polling mode. Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-10net: add vlan_get_protocol_and_depth() helperEric Dumazet1-1/+1
Before blamed commit, pskb_may_pull() was used instead of skb_header_pointer() in __vlan_get_protocol() and friends. Few callers depended on skb->head being populated with MAC header, syzbot caught one of them (skb_mac_gso_segment()) Add vlan_get_protocol_and_depth() to make the intent clearer and use it where sensible. This is a more generic fix than commit e9d3f80935b6 ("net/af_packet: make sure to pull mac header") which was dealing with a similar issue. kernel BUG at include/linux/skbuff.h:2655 ! invalid opcode: 0000 [#1] SMP KASAN CPU: 0 PID: 1441 Comm: syz-executor199 Not tainted 6.1.24-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:__skb_pull include/linux/skbuff.h:2655 [inline] RIP: 0010:skb_mac_gso_segment+0x68f/0x6a0 net/core/gro.c:136 Code: fd 48 8b 5c 24 10 44 89 6b 70 48 c7 c7 c0 ae 0d 86 44 89 e6 e8 a1 91 d0 00 48 c7 c7 00 af 0d 86 48 89 de 31 d2 e8 d1 4a e9 ff <0f> 0b 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41 RSP: 0018:ffffc90001bd7520 EFLAGS: 00010286 RAX: ffffffff8469736a RBX: ffff88810f31dac0 RCX: ffff888115a18b00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90001bd75e8 R08: ffffffff84697183 R09: fffff5200037adf9 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000012 R13: 000000000000fee5 R14: 0000000000005865 R15: 000000000000fed7 FS: 000055555633f300(0000) GS:ffff8881f6a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000000 CR3: 0000000116fea000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> [<ffffffff847018dd>] __skb_gso_segment+0x32d/0x4c0 net/core/dev.c:3419 [<ffffffff8470398a>] skb_gso_segment include/linux/netdevice.h:4819 [inline] [<ffffffff8470398a>] validate_xmit_skb+0x3aa/0xee0 net/core/dev.c:3725 [<ffffffff84707042>] __dev_queue_xmit+0x1332/0x3300 net/core/dev.c:4313 [<ffffffff851a9ec7>] dev_queue_xmit+0x17/0x20 include/linux/netdevice.h:3029 [<ffffffff851b4a82>] packet_snd net/packet/af_packet.c:3111 [inline] [<ffffffff851b4a82>] packet_sendmsg+0x49d2/0x6470 net/packet/af_packet.c:3142 [<ffffffff84669a12>] sock_sendmsg_nosec net/socket.c:716 [inline] [<ffffffff84669a12>] sock_sendmsg net/socket.c:736 [inline] [<ffffffff84669a12>] __sys_sendto+0x472/0x5f0 net/socket.c:2139 [<ffffffff84669c75>] __do_sys_sendto net/socket.c:2151 [inline] [<ffffffff84669c75>] __se_sys_sendto net/socket.c:2147 [inline] [<ffffffff84669c75>] __x64_sys_sendto+0xe5/0x100 net/socket.c:2147 [<ffffffff8551d40f>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [<ffffffff8551d40f>] do_syscall_64+0x2f/0x50 arch/x86/entry/common.c:80 [<ffffffff85600087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: 469aceddfa3e ("vlan: consolidate VLAN parsing code and limit max parsing depth") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Toke Høiland-Jørgensen <toke@redhat.com> Cc: Willem de Bruijn <willemb@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-23net: optimize napi_threaded_poll() vs RPS/RFSEric Dumazet1-2/+10
We use napi_threaded_poll() in order to reduce our softirq dependency. We can add a followup of 821eba962d95 ("net: optimize napi_schedule_rps()") to further remove the need of firing NET_RX_SOFTIRQ whenever RPS/RFS are used. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-23net: make napi_threaded_poll() aware of sd->defer_listEric Dumazet1-0/+3
If we call skb_defer_free_flush() from napi_threaded_poll(), we can avoid to raise IPI from skb_attempt_defer_free() when the list becomes too big. This allows napi_threaded_poll() to rely less on softirqs, and lowers latency caused by a too big list. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-23net: move skb_defer_free_flush() upEric Dumazet1-21/+21
We plan using skb_defer_free_flush() from napi_threaded_poll() in the following patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-23net: do not provide hard irq safety for sd->defer_lockEric Dumazet1-2/+2
kfree_skb() can be called from hard irq handlers, but skb_attempt_defer_free() is meant to be used from process or BH contexts, and skb_defer_free_flush() is meant to be called from BH contexts. Not having to mask hard irq can save some cycles. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-21net: skbuff: update and rename __kfree_skb_defer()Jakub Kicinski1-1/+2
__kfree_skb_defer() uses the old naming where "defer" meant slab bulk free/alloc APIs. In the meantime we also made __kfree_skb_defer() feed the per-NAPI skb cache, which implies bulk APIs. So take away the 'defer' and add 'napi'. While at it add a drop reason. This only matters on the tx_action path, if the skb has a frag_list. But getting rid of a SKB_DROP_REASON_NOT_SPECIFIED seems like a net benefit so why not. Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://lore.kernel.org/r/20230420020005.815854-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-19net: skbuff: hide csum_not_inet when CONFIG_IP_SCTP not setJakub Kicinski1-2/+1
SCTP is not universally deployed, allow hiding its bit from the skb. Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-15page_pool: allow caching from safely localized NAPIJakub Kicinski1-0/+3
Recent patches to mlx5 mentioned a regression when moving from driver local page pool to only using the generic page pool code. Page pool has two recycling paths (1) direct one, which runs in safe NAPI context (basically consumer context, so producing can be lockless); and (2) via a ptr_ring, which takes a spin lock because the freeing can happen from any CPU; producer and consumer may run concurrently. Since the page pool code was added, Eric introduced a revised version of deferred skb freeing. TCP skbs are now usually returned to the CPU which allocated them, and freed in softirq context. This places the freeing (producing of pages back to the pool) enticingly close to the allocation (consumer). If we can prove that we're freeing in the same softirq context in which the consumer NAPI will run - lockless use of the cache is perfectly fine, no need for the lock. Let drivers link the page pool to a NAPI instance. If the NAPI instance is scheduled on the same CPU on which we're freeing - place the pages in the direct cache. With that and patched bnxt (XDP enabled to engage the page pool, sigh, bnxt really needs page pool work :() I see a 2.6% perf boost with a TCP stream test (app on a different physical core than softirq). The CPU use of relevant functions decreases as expected: page_pool_refill_alloc_cache 1.17% -> 0% _raw_spin_lock 2.41% -> 0.98% Only consider lockless path to be safe when NAPI is scheduled - in practice this should cover majority if not all of steady state workloads. It's usually the NAPI kicking in that causes the skb flush. The main case we'll miss out on is when application runs on the same CPU as NAPI. In that case we don't use the deferred skb free path. Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Dragos Tatulea <dtatulea@nvidia.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+2
Conflicts: tools/testing/selftests/net/config 62199e3f1658 ("selftests: net: Add VXLAN MDB test") 3a0385be133e ("selftests: add the missing CONFIG_IP_SCTP in net config") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-13rtnetlink: Restore RTM_NEW/DELLINK notification behaviorMartin Willi1-1/+1
The commits referenced below allows userspace to use the NLM_F_ECHO flag for RTM_NEW/DELLINK operations to receive unicast notifications for the affected link. Prior to these changes, applications may have relied on multicast notifications to learn the same information without specifying the NLM_F_ECHO flag. For such applications, the mentioned commits changed the behavior for requests not using NLM_F_ECHO. Multicast notifications are still received, but now use the portid of the requester and the sequence number of the request instead of zero values used previously. For the application, this message may be unexpected and likely handled as a response to the NLM_F_ACKed request, especially if it uses the same socket to handle requests and notifications. To fix existing applications relying on the old notification behavior, set the portid and sequence number in the notification only if the request included the NLM_F_ECHO flag. This restores the old behavior for applications not using it, but allows unicasted notifications for others. Fixes: f3a63cce1b4f ("rtnetlink: Honour NLM_F_ECHO flag in rtnl_delete_link") Fixes: d88e136cab37 ("rtnetlink: Honour NLM_F_ECHO flag in rtnl_newlink_create") Signed-off-by: Martin Willi <martin@strongswan.org> Acked-by: Guillaume Nault <gnault@redhat.com> Acked-by: Hangbin Liu <liuhangbin@gmail.com> Link: https://lore.kernel.org/r/20230411074319.24133-1-martin@strongswan.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-09net: dsa: replace NETDEV_PRE_CHANGE_HWTSTAMP notifier with a stubVladimir Oltean1-1/+1
There was a sort of rush surrounding commit 88c0a6b503b7 ("net: create a netdev notifier for DSA to reject PTP on DSA master"), due to a desire to convert DSA's attempt to deny TX timestamping on a DSA master to something that doesn't block the kernel-wide API conversion from ndo_eth_ioctl() to ndo_hwtstamp_set(). What was required was a mechanism that did not depend on ndo_eth_ioctl(), and what was provided was a mechanism that did not depend on ndo_eth_ioctl(), while at the same time introducing something that wasn't absolutely necessary - a new netdev notifier. There have been objections from Jakub Kicinski that using notifiers in general when they are not absolutely necessary creates complications to the control flow and difficulties to maintainers who look at the code. So there is a desire to not use notifiers. In addition to that, the notifier chain gets called even if there is no DSA in the system and no one is interested in applying any restriction. Take the model of udp_tunnel_nic_ops and introduce a stub mechanism, through which net/core/dev_ioctl.c can call into DSA even when CONFIG_NET_DSA=m. Compared to the code that existed prior to the notifier conversion, aka what was added in commits: - 4cfab3566710 ("net: dsa: Add wrappers for overloaded ndo_ops") - 3369afba1e46 ("net: Call into DSA netdevice_ops wrappers") this is different because we are not overloading any struct net_device_ops of the DSA master anymore, but rather, we are exposing a rather specific functionality which is orthogonal to which API is used to enable it - ndo_eth_ioctl() or ndo_hwtstamp_set(). Also, what is similar is that both approaches use function pointers to get from built-in code to DSA. There is no point in replicating the function pointers towards __dsa_master_hwtstamp_validate() once for every CPU port (dev->dsa_ptr). Instead, it is sufficient to introduce a singleton struct dsa_stubs, built into the kernel, which contains a single function pointer to __dsa_master_hwtstamp_validate(). I find this approach preferable to what we had originally, because dev->dsa_ptr->netdev_ops->ndo_do_ioctl() used to require going through struct dsa_port (dev->dsa_ptr), and so, this was incompatible with any attempts to add any data encapsulation and hide DSA data structures from the outside world. Link: https://lore.kernel.org/netdev/20230403083019.120b72fd@kernel.org/ Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-08net: openvswitch: fix race on port outputFelix Huettner1-0/+1
assume the following setup on a single machine: 1. An openvswitch instance with one bridge and default flows 2. two network namespaces "server" and "client" 3. two ovs interfaces "server" and "client" on the bridge 4. for each ovs interface a veth pair with a matching name and 32 rx and tx queues 5. move the ends of the veth pairs to the respective network namespaces 6. assign ip addresses to each of the veth ends in the namespaces (needs to be the same subnet) 7. start some http server on the server network namespace 8. test if a client in the client namespace can reach the http server when following the actions below the host has a chance of getting a cpu stuck in a infinite loop: 1. send a large amount of parallel requests to the http server (around 3000 curls should work) 2. in parallel delete the network namespace (do not delete interfaces or stop the server, just kill the namespace) there is a low chance that this will cause the below kernel cpu stuck message. If this does not happen just retry. Below there is also the output of bpftrace for the functions mentioned in the output. The series of events happening here is: 1. the network namespace is deleted calling `unregister_netdevice_many_notify` somewhere in the process 2. this sets first `NETREG_UNREGISTERING` on both ends of the veth and then runs `synchronize_net` 3. it then calls `call_netdevice_notifiers` with `NETDEV_UNREGISTER` 4. this is then handled by `dp_device_event` which calls `ovs_netdev_detach_dev` (if a vport is found, which is the case for the veth interface attached to ovs) 5. this removes the rx_handlers of the device but does not prevent packages to be sent to the device 6. `dp_device_event` then queues the vport deletion to work in background as a ovs_lock is needed that we do not hold in the unregistration path 7. `unregister_netdevice_many_notify` continues to call `netdev_unregister_kobject` which sets `real_num_tx_queues` to 0 8. port deletion continues (but details are not relevant for this issue) 9. at some future point the background task deletes the vport If after 7. but before 9. a packet is send to the ovs vport (which is not deleted at this point in time) which forwards it to the `dev_queue_xmit` flow even though the device is unregistering. In `skb_tx_hash` (which is called in the `dev_queue_xmit`) path there is a while loop (if the packet has a rx_queue recorded) that is infinite if `dev->real_num_tx_queues` is zero. To prevent this from happening we update `do_output` to handle devices without carrier the same as if the device is not found (which would be the code path after 9. is done). Additionally we now produce a warning in `skb_tx_hash` if we will hit the infinite loop. bpftrace (first word is function name): __dev_queue_xmit server: real_num_tx_queues: 1, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 1 netdev_core_pick_tx server: addr: 0xffff9f0a46d4a000 real_num_tx_queues: 1, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 1 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 2, reg_state: 1 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 6, reg_state: 2 ovs_netdev_detach_dev server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, reg_state: 2 netdev_rx_handler_unregister server: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024, reg_state: 2 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 netdev_rx_handler_unregister ret server: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024, reg_state: 2 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 27, reg_state: 2 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 22, reg_state: 2 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 18, reg_state: 2 netdev_unregister_kobject: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 ovs_vport_send server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2 __dev_queue_xmit server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2 netdev_core_pick_tx server: addr: 0xffff9f0a46d4a000 real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2 broken device server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024 ovs_dp_detach_port server: real_num_tx_queues: 0 cpu 9, pid: 9124, tid: 9124, reg_state: 2 synchronize_rcu_expedited: cpu 9, pid: 33604, tid: 33604 stuck message: watchdog: BUG: soft lockup - CPU#5 stuck for 26s! [curl:1929279] Modules linked in: veth pktgen bridge stp llc ip_set_hash_net nft_counter xt_set nft_compat nf_tables ip_set_hash_ip ip_set nfnetlink_cttimeout nfnetlink openvswitch nsh nf_conncount nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 tls binfmt_misc nls_iso8859_1 input_leds joydev serio_raw dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua sch_fq_codel drm efi_pstore virtio_rng ip_tables x_tables autofs4 btrfs blake2b_generic zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear hid_generic usbhid hid crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel virtio_net ahci net_failover crypto_simd cryptd psmouse libahci virtio_blk failover CPU: 5 PID: 1929279 Comm: curl Not tainted 5.15.0-67-generic #74-Ubuntu Hardware name: OpenStack Foundation OpenStack Nova, BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:netdev_pick_tx+0xf1/0x320 Code: 00 00 8d 48 ff 0f b7 c1 66 39 ca 0f 86 e9 01 00 00 45 0f b7 ff 41 39 c7 0f 87 5b 01 00 00 44 29 f8 41 39 c7 0f 87 4f 01 00 00 <eb> f2 0f 1f 44 00 00 49 8b 94 24 28 04 00 00 48 85 d2 0f 84 53 01 RSP: 0018:ffffb78b40298820 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff9c8773adc2e0 RCX: 000000000000083f RDX: 0000000000000000 RSI: ffff9c8773adc2e0 RDI: ffff9c870a25e000 RBP: ffffb78b40298858 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff9c870a25e000 R13: ffff9c870a25e000 R14: ffff9c87fe043480 R15: 0000000000000000 FS: 00007f7b80008f00(0000) GS:ffff9c8e5f740000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7b80f6a0b0 CR3: 0000000329d66000 CR4: 0000000000350ee0 Call Trace: <IRQ> netdev_core_pick_tx+0xa4/0xb0 __dev_queue_xmit+0xf8/0x510 ? __bpf_prog_exit+0x1e/0x30 dev_queue_xmit+0x10/0x20 ovs_vport_send+0xad/0x170 [openvswitch] do_output+0x59/0x180 [openvswitch] do_execute_actions+0xa80/0xaa0 [openvswitch] ? kfree+0x1/0x250 ? kfree+0x1/0x250 ? kprobe_perf_func+0x4f/0x2b0 ? flow_lookup.constprop.0+0x5c/0x110 [openvswitch] ovs_execute_actions+0x4c/0x120 [openvswitch] ovs_dp_process_packet+0xa1/0x200 [openvswitch] ? ovs_ct_update_key.isra.0+0xa8/0x120 [openvswitch] ? ovs_ct_fill_key+0x1d/0x30 [openvswitch] ? ovs_flow_key_extract+0x2db/0x350 [openvswitch] ovs_vport_receive+0x77/0xd0 [openvswitch] ? __htab_map_lookup_elem+0x4e/0x60 ? bpf_prog_680e8aff8547aec1_kfree+0x3b/0x714 ? trace_call_bpf+0xc8/0x150 ? kfree+0x1/0x250 ? kfree+0x1/0x250 ? kprobe_perf_func+0x4f/0x2b0 ? kprobe_perf_func+0x4f/0x2b0 ? __mod_memcg_lruvec_state+0x63/0xe0 netdev_port_receive+0xc4/0x180 [openvswitch] ? netdev_port_receive+0x180/0x180 [openvswitch] netdev_frame_hook+0x1f/0x40 [openvswitch] __netif_receive_skb_core.constprop.0+0x23d/0xf00 __netif_receive_skb_one_core+0x3f/0xa0 __netif_receive_skb+0x15/0x60 process_backlog+0x9e/0x170 __napi_poll+0x33/0x180 net_rx_action+0x126/0x280 ? ttwu_do_activate+0x72/0xf0 __do_softirq+0xd9/0x2e7 ? rcu_report_exp_cpu_mult+0x1b0/0x1b0 do_softirq+0x7d/0xb0 </IRQ> <TASK> __local_bh_enable_ip+0x54/0x60 ip_finish_output2+0x191/0x460 __ip_finish_output+0xb7/0x180 ip_finish_output+0x2e/0xc0 ip_output+0x78/0x100 ? __ip_finish_output+0x180/0x180 ip_local_out+0x5e/0x70 __ip_queue_xmit+0x184/0x440 ? tcp_syn_options+0x1f9/0x300 ip_queue_xmit+0x15/0x20 __tcp_transmit_skb+0x910/0x9c0 ? __mod_memcg_state+0x44/0xa0 tcp_connect+0x437/0x4e0 ? ktime_get_with_offset+0x60/0xf0 tcp_v4_connect+0x436/0x530 __inet_stream_connect+0xd4/0x3a0 ? kprobe_perf_func+0x4f/0x2b0 ? aa_sk_perm+0x43/0x1c0 inet_stream_connect+0x3b/0x60 __sys_connect_file+0x63/0x70 __sys_connect+0xa6/0xd0 ? setfl+0x108/0x170 ? do_fcntl+0xe8/0x5a0 __x64_sys_connect+0x18/0x20 do_syscall_64+0x5c/0xc0 ? __x64_sys_fcntl+0xa9/0xd0 ? exit_to_user_mode_prepare+0x37/0xb0 ? syscall_exit_to_user_mode+0x27/0x50 ? do_syscall_64+0x69/0xc0 ? __sys_setsockopt+0xea/0x1e0 ? exit_to_user_mode_prepare+0x37/0xb0 ? syscall_exit_to_user_mode+0x27/0x50 ? __x64_sys_setsockopt+0x1f/0x30 ? do_syscall_64+0x69/0xc0 ? irqentry_exit+0x1d/0x30 ? exc_page_fault+0x89/0x170 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f7b8101c6a7 Code: 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 18 89 54 24 0c 48 89 34 24 89 RSP: 002b:00007ffffd6b2198 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7b8101c6a7 RDX: 0000000000000010 RSI: 00007ffffd6b2360 RDI: 0000000000000005 RBP: 0000561f1370d560 R08: 00002795ad21d1ac R09: 0030312e302e302e R10: 00007ffffd73f080 R11: 0000000000000246 R12: 0000561f1370c410 R13: 0000000000000000 R14: 0000000000000005 R15: 0000000000000000 </TASK> Fixes: 7f8a436eaa2c ("openvswitch: Add conntrack action") Co-developed-by: Luca Czesla <luca.czesla@mail.schwarz> Signed-off-by: Luca Czesla <luca.czesla@mail.schwarz> Signed-off-by: Felix Huettner <felix.huettner@mail.schwarz> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Link: https://lore.kernel.org/r/ZC0pBXBAgh7c76CA@kernel-bug-kernel-bug Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-03net: create a netdev notifier for DSA to reject PTP on DSA masterVladimir Oltean1-5/+3
The fact that PTP 2-step TX timestamping is broken on DSA switches if the master also timestamps the same packets is documented by commit f685e609a301 ("net: dsa: Deny PTP on master if switch supports it"). We attempt to help the users avoid shooting themselves in the foot by making DSA reject the timestamping ioctls on an interface that is a DSA master, and the switch tree beneath it contains switches which are aware of PTP. The only problem is that there isn't an established way of intercepting ndo_eth_ioctl calls, so DSA creates avoidable burden upon the network stack by creating a struct dsa_netdevice_ops with overlaid function pointers that are manually checked from the relevant call sites. There used to be 2 such dsa_netdevice_ops, but now, ndo_eth_ioctl is the only one left. There is an ongoing effort to migrate driver-visible hardware timestamping control from the ndo_eth_ioctl() based API to a new ndo_hwtstamp_set() model, but DSA actively prevents that migration, since dsa_master_ioctl() is currently coded to manually call the master's legacy ndo_eth_ioctl(), and so, whenever a network device driver would be converted to the new API, DSA's restrictions would be circumvented, because any device could be used as a DSA master. The established way for unrelated modules to react on a net device event is via netdevice notifiers. So we create a new notifier which gets called whenever there is an attempt to change hardware timestamping settings on a device. Finally, there is another reason why a netdev notifier will be a good idea, besides strictly DSA, and this has to do with PHY timestamping. With ndo_eth_ioctl(), all MAC drivers must manually call phy_has_hwtstamp() before deciding whether to act upon SIOCSHWTSTAMP, otherwise they must pass this ioctl to the PHY driver via phy_mii_ioctl(). With the new ndo_hwtstamp_set() API, it will be desirable to simply not make any calls into the MAC device driver when timestamping should be performed at the PHY level. But there exist drivers, such as the lan966x switch, which need to install packet traps for PTP regardless of whether they are the layer that provides the hardware timestamps, or the PHY is. That would be impossible to support with the new API. The proposal there, too, is to introduce a netdev notifier which acts as a better cue for switching drivers to add or remove PTP packet traps, than ndo_hwtstamp_set(). The one introduced here "almost" works there as well, except for the fact that packet traps should only be installed if the PHY driver succeeded to enable hardware timestamping, whereas here, we need to deny hardware timestamping on the DSA master before it actually gets enabled. This is why this notifier is called "PRE_", and the notifier that would get used for PHY timestamping and packet traps would be called NETDEV_CHANGE_HWTSTAMP. This isn't a new concept, for example NETDEV_CHANGEUPPER and NETDEV_PRECHANGEUPPER do the same thing. In expectation of future netlink UAPI, we also pass a non-NULL extack pointer to the netdev notifier, and we make DSA populate it with an informative reason for the rejection. To avoid making it go to waste, we make the ioctl-based dev_set_hwtstamp() create a fake extack and print the message to the kernel log. Link: https://lore.kernel.org/netdev/20230401191215.tvveoi3lkawgg6g4@skbuf/ Link: https://lore.kernel.org/netdev/20230310164451.ls7bbs6pdzs4m6pw@skbuf/ Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-30net: optimize ____napi_schedule() to avoid extra NET_RX_SOFTIRQEric Dumazet1-4/+18
____napi_schedule() adds a napi into current cpu softnet_data poll_list, then raises NET_RX_SOFTIRQ to make sure net_rx_action() will process it. Idea of this patch is to not raise NET_RX_SOFTIRQ when being called indirectly from net_rx_action(), because we can process poll_list from this point, without going to full softirq loop. This needs a change in net_rx_action() to make sure we restart its main loop if sd->poll_list was updated without NET_RX_SOFTIRQ being raised. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jason Xing <kernelxing@tencent.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Tested-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30net: optimize napi_schedule_rps()Eric Dumazet1-3/+5
Based on initial patch from Jason Xing. Idea is to not raise NET_RX_SOFTIRQ from napi_schedule_rps() when we queued a packet into another cpu backlog. We can do this only in the context of us being called indirectly from net_rx_action(), to have the guarantee our rps_ipi_list will be processed before we exit from net_rx_action(). Link: https://lore.kernel.org/lkml/20230325152417.5403-1-kerneljasonxing@gmail.com/ Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jason Xing <kernelxing@tencent.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Tested-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30net: add softnet_data.in_net_rx_actionEric Dumazet1-0/+4
We want to make two optimizations in napi_schedule_rps() and ____napi_schedule() which require to know if these helpers are called from net_rx_action(), instead of being called from other contexts. sd.in_net_rx_action is only read/written by the owning cpu. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Tested-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-30net: napi_schedule_rps() cleanupEric Dumazet1-6/+12
napi_schedule_rps() return value is ignored, remove it. Change the comment to clarify the intent. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Tested-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-23net: do not use skb_mac_header() in qdisc_pkt_len_init()Eric Dumazet1-4/+4
We want to remove our use of skb_mac_header() in tx paths, eg remove skb_reset_mac_header() from __dev_queue_xmit(). Idea is that ndo_start_xmit() can get the mac header simply looking at skb->data. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-23net: Catch invalid index in XPS mappingNick Child1-0/+2
When setting the XPS value of a TX queue, warn the user once if the index of the queue is greater than the number of allocated TX queues. Previously, this scenario went uncaught. In the best case, it resulted in unnecessary allocations. In the worst case, it resulted in out-of-bounds memory references through calls to `netdev_get_tx_queue( dev, index)`. Therefore, it is important to inform the user but not worth returning an error and risk downing the netdevice. Signed-off-by: Nick Child <nnac123@linux.ibm.com> Reviewed-by: Piotr Raczynski <piotr.raczynski@intel.com> Link: https://lore.kernel.org/r/20230321150725.127229-1-nnac123@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-08net: remove enum skb_free_reasonEric Dumazet1-11/+9
enum skb_drop_reason is more generic, we can adopt it instead. Provide dev_kfree_skb_irq_reason() and dev_kfree_skb_any_reason(). This means drivers can use more precise drop reasons if they want to. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com> Link: https://lore.kernel.org/r/20230306204313.10492-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-24net: fix __dev_kfree_skb_any() vs drop monitorEric Dumazet1-1/+3
dev_kfree_skb() is aliased to consume_skb(). When a driver is dropping a packet by calling dev_kfree_skb_any() we should propagate the drop reason instead of pretending the packet was consumed. Note: Now we have enum skb_drop_reason we could remove enum skb_free_reason (for linux-6.4) v2: added an unlikely(), suggested by Yunsheng Lin. Fixes: e6247027e517 ("net: introduce dev_consume_skb_any()") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yunsheng Lin <linyunsheng@huawei.com> Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>