summaryrefslogtreecommitdiff
path: root/kernel/bpf/devmap.c
AgeCommit message (Collapse)Author
2019-06-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: "Lots of bug fixes here: 1) Out of bounds access in __bpf_skc_lookup, from Lorenz Bauer. 2) Fix rate reporting in cfg80211_calculate_bitrate_he(), from John Crispin. 3) Use after free in psock backlog workqueue, from John Fastabend. 4) Fix source port matching in fdb peer flow rule of mlx5, from Raed Salem. 5) Use atomic_inc_not_zero() in fl6_sock_lookup(), from Eric Dumazet. 6) Network header needs to be set for packet redirect in nfp, from John Hurley. 7) Fix udp zerocopy refcnt, from Willem de Bruijn. 8) Don't assume linear buffers in vxlan and geneve error handlers, from Stefano Brivio. 9) Fix TOS matching in mlxsw, from Jiri Pirko. 10) More SCTP cookie memory leak fixes, from Neil Horman. 11) Fix VLAN filtering in rtl8366, from Linus Walluij. 12) Various TCP SACK payload size and fragmentation memory limit fixes from Eric Dumazet. 13) Use after free in pneigh_get_next(), also from Eric Dumazet. 14) LAPB control block leak fix from Jeremy Sowden" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (145 commits) lapb: fixed leak of control-blocks. tipc: purge deferredq list for each grp member in tipc_group_delete ax25: fix inconsistent lock state in ax25_destroy_timer neigh: fix use-after-free read in pneigh_get_next tcp: fix compile error if !CONFIG_SYSCTL hv_sock: Suppress bogus "may be used uninitialized" warnings be2net: Fix number of Rx queues used for flow hashing net: handle 802.1P vlan 0 packets properly tcp: enforce tcp_min_snd_mss in tcp_mtu_probing() tcp: add tcp_min_snd_mss sysctl tcp: tcp_fragment() should apply sane memory limits tcp: limit payload size of sacked skbs Revert "net: phylink: set the autoneg state in phylink_phy_change" bpf: fix nested bpf tracepoints with per-cpu data bpf: Fix out of bounds memory access in bpf_sk_storage vsock/virtio: set SOCK_DONE on peer shutdown net: dsa: rtl8366: Fix up VLAN filtering net: phylink: set the autoneg state in phylink_phy_change net: add high_order_alloc_disable sysctl/static key tcp: add tcp_tx_skb_cache sysctl ...
2019-06-15bpf, devmap: Add missing RCU read lock on flushToshiaki Makita
.ndo_xdp_xmit() assumes it is called under RCU. For example virtio_net uses RCU to detect it has setup the resources for tx. The assumption accidentally broke when introducing bulk queue in devmap. Fixes: 5d053f9da431 ("bpf: devmap prepare xdp frames for bulking") Reported-by: David Ahern <dsahern@gmail.com> Signed-off-by: Toshiaki Makita <toshiaki.makita1@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-06-15bpf, devmap: Add missing bulk queue freeToshiaki Makita
dev_map_free() forgot to free bulk queue when freeing its entries. Fixes: 5d053f9da431 ("bpf: devmap prepare xdp frames for bulking") Signed-off-by: Toshiaki Makita <toshiaki.makita1@gmail.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-06-15bpf, devmap: Fix premature entry free on destroying mapToshiaki Makita
dev_map_free() waits for flush_needed bitmap to be empty in order to ensure all flush operations have completed before freeing its entries. However the corresponding clear_bit() was called before using the entries, so the entries could be used after free. All access to the entries needs to be done before clearing the bit. It seems commit a5e2da6e9787 ("bpf: netdev is never null in __dev_map_flush") accidentally changed the clear_bit() and memory access order. Note that the problem happens only in __dev_map_flush(), not in dev_map_flush_old(). dev_map_flush_old() is called only after nulling out the corresponding netdev_map entry, so dev_map_free() never frees the entry thus no such race happens there. Fixes: a5e2da6e9787 ("bpf: netdev is never null in __dev_map_flush") Signed-off-by: Toshiaki Makita <toshiaki.makita1@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of version 2 of the gnu general public license as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 64 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.894819585@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-14bpf: devmap: fix use-after-free Read in __dev_map_entry_freeEric Dumazet
synchronize_rcu() is fine when the rcu callbacks only need to free memory (kfree_rcu() or direct kfree() call rcu call backs) __dev_map_entry_free() is a bit more complex, so we need to make sure that call queued __dev_map_entry_free() callbacks have completed. sysbot report: BUG: KASAN: use-after-free in dev_map_flush_old kernel/bpf/devmap.c:365 [inline] BUG: KASAN: use-after-free in __dev_map_entry_free+0x2a8/0x300 kernel/bpf/devmap.c:379 Read of size 8 at addr ffff8801b8da38c8 by task ksoftirqd/1/18 CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 4.17.0+ #39 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 dev_map_flush_old kernel/bpf/devmap.c:365 [inline] __dev_map_entry_free+0x2a8/0x300 kernel/bpf/devmap.c:379 __rcu_reclaim kernel/rcu/rcu.h:178 [inline] rcu_do_batch kernel/rcu/tree.c:2558 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2818 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2785 [inline] rcu_process_callbacks+0xe9d/0x1760 kernel/rcu/tree.c:2802 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:284 run_ksoftirqd+0x86/0x100 kernel/softirq.c:645 smpboot_thread_fn+0x417/0x870 kernel/smpboot.c:164 kthread+0x345/0x410 kernel/kthread.c:240 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Allocated by task 6675: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620 kmalloc include/linux/slab.h:513 [inline] kzalloc include/linux/slab.h:706 [inline] dev_map_alloc+0x208/0x7f0 kernel/bpf/devmap.c:102 find_and_alloc_map kernel/bpf/syscall.c:129 [inline] map_create+0x393/0x1010 kernel/bpf/syscall.c:453 __do_sys_bpf kernel/bpf/syscall.c:2351 [inline] __se_sys_bpf kernel/bpf/syscall.c:2328 [inline] __x64_sys_bpf+0x303/0x510 kernel/bpf/syscall.c:2328 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 26: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 dev_map_free+0x4fa/0x670 kernel/bpf/devmap.c:191 bpf_map_free_deferred+0xba/0xf0 kernel/bpf/syscall.c:262 process_one_work+0xc64/0x1b70 kernel/workqueue.c:2153 worker_thread+0x181/0x13a0 kernel/workqueue.c:2296 kthread+0x345/0x410 kernel/kthread.c:240 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 The buggy address belongs to the object at ffff8801b8da37c0 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 264 bytes inside of 512-byte region [ffff8801b8da37c0, ffff8801b8da39c0) The buggy address belongs to the page: page:ffffea0006e368c0 count:1 mapcount:0 mapping:ffff8801da800940 index:0xffff8801b8da3540 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea0007217b88 ffffea0006e30cc8 ffff8801da800940 raw: ffff8801b8da3540 ffff8801b8da3040 0000000100000004 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801b8da3780: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8801b8da3800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8801b8da3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801b8da3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801b8da3980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc Fixes: 546ac1ffb70d ("bpf: add devmap, a map for storing net device references") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot+457d3e2ffbcf31aee5c0@syzkaller.appspotmail.com Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-26bpf: devmap: fix wrong interface selection in notifier_callTaehee Yoo
The dev_map_notification() removes interface in devmap if unregistering interface's ifindex is same. But only checking ifindex is not enough because other netns can have same ifindex. so that wrong interface selection could occurred. Hence netdev pointer comparison code is added. v2: compare netdev pointer instead of using net_eq() (Daniel Borkmann) v1: Initial patch Fixes: 2ddf71e23cc2 ("net: add notifier hooks for devmap bpf map") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-17bpf: fix redirect to map under tail callsDaniel Borkmann
Commits 109980b894e9 ("bpf: don't select potentially stale ri->map from buggy xdp progs") and 7c3001313396 ("bpf: fix ri->map_owner pointer on bpf_prog_realloc") tried to mitigate that buggy programs using bpf_redirect_map() helper call do not leave stale maps behind. Idea was to add a map_owner cookie into the per CPU struct redirect_info which was set to prog->aux by the prog making the helper call as a proof that the map is not stale since the prog is implicitly holding a reference to it. This owner cookie could later on get compared with the program calling into BPF whether they match and therefore the redirect could proceed with processing the map safely. In (obvious) hindsight, this approach breaks down when tail calls are involved since the original caller's prog->aux pointer does not have to match the one from one of the progs out of the tail call chain, and therefore the xdp buffer will be dropped instead of redirected. A way around that would be to fix the issue differently (which also allows to remove related work in fast path at the same time): once the life-time of a redirect map has come to its end we use it's map free callback where we need to wait on synchronize_rcu() for current outstanding xdp buffers and remove such a map pointer from the redirect info if found to be present. At that time no program is using this map anymore so we simply invalidate the map pointers to NULL iff they previously pointed to that instance while making sure that the redirect path only reads out the map once. Fixes: 97f91a7cf04f ("bpf: add bpf_redirect_map helper routine") Fixes: 109980b894e9 ("bpf: don't select potentially stale ri->map from buggy xdp progs") Reported-by: Sebastiano Miano <sebastiano.miano@polito.it> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf-next 2018-08-13 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Add driver XDP support for veth. This can be used in conjunction with redirect of another XDP program e.g. sitting on NIC so the xdp_frame can be forwarded to the peer veth directly without modification, from Toshiaki. 2) Add a new BPF map type REUSEPORT_SOCKARRAY and prog type SK_REUSEPORT in order to provide more control and visibility on where a SO_REUSEPORT sk should be located, and the latter enables to directly select a sk from the bpf map. This also enables map-in-map for application migration use cases, from Martin. 3) Add a new BPF helper bpf_skb_ancestor_cgroup_id() that returns the id of cgroup v2 that is the ancestor of the cgroup associated with the skb at the ancestor_level, from Andrey. 4) Implement BPF fs map pretty-print support based on BTF data for regular hash table and LRU map, from Yonghong. 5) Decouple the ability to attach BTF for a map from the key and value pretty-printer in BPF fs, and enable further support of BTF for maps for percpu and LPM trie, from Daniel. 6) Implement a better BPF sample of using XDP's CPU redirect feature for load balancing SKB processing to remote CPU. The sample implements the same XDP load balancing as Suricata does which is symmetric hash based on IP and L4 protocol, from Jesper. 7) Revert adding NULL pointer check with WARN_ON_ONCE() in __xdp_return()'s critical path as it is ensured that the allocator is present, from Björn. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-13bpf: decouple btf from seq bpf fs dump and enable more mapsDaniel Borkmann
Commit a26ca7c982cb ("bpf: btf: Add pretty print support to the basic arraymap") and 699c86d6ec21 ("bpf: btf: add pretty print for hash/lru_hash maps") enabled support for BTF and dumping via BPF fs for array and hash/lru map. However, both can be decoupled from each other such that regular BPF maps can be supported for attaching BTF key/value information, while not all maps necessarily need to dump via map_seq_show_elem() callback. The basic sanity check which is a prerequisite for all maps is that key/value size has to match in any case, and some maps can have extra checks via map_check_btf() callback, e.g. probing certain types or indicating no support in general. With that we can also enable retrieving BTF info for per-cpu map types and lpm. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com>
2018-08-09xdp: fix bug in devmap teardown code pathJesper Dangaard Brouer
Like cpumap teardown, the devmap teardown code also flush remaining xdp_frames, via bq_xmit_all() in case map entry is removed. The code can call xdp_return_frame_rx_napi, from the the wrong context, in-case ndo_xdp_xmit() fails. Fixes: 389ab7f01af9 ("xdp: introduce xdp_return_frame_rx_napi") Fixes: 735fc4054b3a ("xdp: change ndo_xdp_xmit API to support bulking") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-07xdp: XDP_REDIRECT should check IFF_UP and MTUToshiaki Makita
Otherwise we end up with attempting to send packets from down devices or to send oversized packets, which may cause unexpected driver/device behaviour. Generic XDP has already done this check, so reuse the logic in native XDP. Fixes: 814abfabef3c ("xdp: add bpf_redirect helper function") Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-06-15xdp: Fix handling of devmap in generic XDPToshiaki Makita
Commit 67f29e07e131 ("bpf: devmap introduce dev_map_enqueue") changed the return value type of __devmap_lookup_elem() from struct net_device * to struct bpf_dtab_netdev * but forgot to modify generic XDP code accordingly. Thus generic XDP incorrectly used struct bpf_dtab_netdev where struct net_device is expected, then skb->dev was set to invalid value. v2: - Fix compiler warning without CONFIG_BPF_SYSCALL. Fixes: 67f29e07e131 ("bpf: devmap introduce dev_map_enqueue") Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-06-03bpf/xdp: devmap can avoid calling ndo_xdp_flushJesper Dangaard Brouer
The XDP_REDIRECT map devmap can avoid using ndo_xdp_flush, by instead instructing ndo_xdp_xmit to flush via XDP_XMIT_FLUSH flag in appropriate places. Notice after this patch it is possible to remove ndo_xdp_flush completely, as this is the last user of ndo_xdp_flush. This is left for later patches, to keep driver changes separate. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-06-03xdp: add flags argument to ndo_xdp_xmit APIJesper Dangaard Brouer
This patch only change the API and reject any use of flags. This is an intermediate step that allows us to implement the flush flag operation later, for each individual driver in a separate patch. The plan is to implement flush operation via XDP_XMIT_FLUSH flag and then remove XDP_XMIT_FLAGS_NONE when done. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-30bpf: devmap: remove redundant assignment of dev = devColin Ian King
The assignment dev = dev is redundant and should be removed. Detected by CoverityScan, CID#1469486 ("Evaluation order violation") Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-24xdp/trace: extend tracepoint in devmap with an errJesper Dangaard Brouer
Extending tracepoint xdp:xdp_devmap_xmit in devmap with an err code allow people to easier identify the reason behind the ndo_xdp_xmit call to a given driver is failing. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-24xdp: change ndo_xdp_xmit API to support bulkingJesper Dangaard Brouer
This patch change the API for ndo_xdp_xmit to support bulking xdp_frames. When kernel is compiled with CONFIG_RETPOLINE, XDP sees a huge slowdown. Most of the slowdown is caused by DMA API indirect function calls, but also the net_device->ndo_xdp_xmit() call. Benchmarked patch with CONFIG_RETPOLINE, using xdp_redirect_map with single flow/core test (CPU E5-1650 v4 @ 3.60GHz), showed performance improved: for driver ixgbe: 6,042,682 pps -> 6,853,768 pps = +811,086 pps for driver i40e : 6,187,169 pps -> 6,724,519 pps = +537,350 pps With frames avail as a bulk inside the driver ndo_xdp_xmit call, further optimizations are possible, like bulk DMA-mapping for TX. Testing without CONFIG_RETPOLINE show the same performance for physical NIC drivers. The virtual NIC driver tun sees a huge performance boost, as it can avoid doing per frame producer locking, but instead amortize the locking cost over the bulk. V2: Fix compile errors reported by kbuild test robot <lkp@intel.com> V4: Isolated ndo, driver changes and callers. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-24xdp: introduce xdp_return_frame_rx_napiJesper Dangaard Brouer
When sending an xdp_frame through xdp_do_redirect call, then error cases can happen where the xdp_frame needs to be dropped, and returning an -errno code isn't sufficient/possible any-longer (e.g. for cpumap case). This is already fully supported, by simply calling xdp_return_frame. This patch is an optimization, which provides xdp_return_frame_rx_napi, which is a faster variant for these error cases. It take advantage of the protection provided by XDP RX running under NAPI protection. This change is mostly relevant for drivers using the page_pool allocator as it can take advantage of this. (Tested with mlx5). Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-24xdp: add tracepoint for devmap like cpumap haveJesper Dangaard Brouer
Notice how this allow us get XDP statistic without affecting the XDP performance, as tracepoint is no-longer activated on a per packet basis. V5: Spotted by John Fastabend. Fix 'sent' also counted 'drops' in this patch, a later patch corrected this, but it was a mistake in this intermediate step. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-24bpf: devmap prepare xdp frames for bulkingJesper Dangaard Brouer
Like cpumap create queue for xdp frames that will be bulked. For now, this patch simply invoke ndo_xdp_xmit foreach frame. This happens, either when the map flush operation is envoked, or when the limit DEV_MAP_BULK_SIZE is reached. V5: Avoid memleak on error path in dev_map_update_elem() Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-24bpf: devmap introduce dev_map_enqueueJesper Dangaard Brouer
Functionality is the same, but the ndo_xdp_xmit call is now simply invoked from inside the devmap.c code. V2: Fix compile issue reported by kbuild test robot <lkp@intel.com> V5: Cleanups requested by Daniel - Newlines before func definition - Use BUILD_BUG_ON checks - Remove unnecessary use return value store in dev_map_enqueue Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-14bpf: add helper for copying attrs to struct bpf_mapJakub Kicinski
All map types reimplement the field-by-field copy of union bpf_attr members into struct bpf_map. Add a helper to perform this operation. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-10-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
There were quite a few overlapping sets of changes here. Daniel's bug fix for off-by-ones in the new BPF branch instructions, along with the added allowances for "data_end > ptr + x" forms collided with the metadata additions. Along with those three changes came veritifer test cases, which in their final form I tried to group together properly. If I had just trimmed GIT's conflict tags as-is, this would have split up the meta tests unnecessarily. In the socketmap code, a set of preemption disabling changes overlapped with the rename of bpf_compute_data_end() to bpf_compute_data_pointers(). Changes were made to the mv88e6060.c driver set addr method which got removed in net-next. The hyperv transport socket layer had a locking change in 'net' which overlapped with a change of socket state macro usage in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-22bpf: devmap fix arithmetic overflow in bitmap_size calculationJohn Fastabend
An integer overflow is possible in dev_map_bitmap_size() when calculating the BITS_TO_LONG logic which becomes, after macro replacement, (((n) + (d) - 1)/ (d)) where 'n' is a __u32 and 'd' is (8 * sizeof(long)). To avoid overflow cast to u64 before arithmetic. Reported-by: Richard Weinberger <richard@nod.at> 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>
2017-10-20bpf: Add file mode configuration into bpf mapsChenbo Feng
Introduce the map read/write flags to the eBPF syscalls that returns the map fd. The flags is used to set up the file mode when construct a new file descriptor for bpf maps. To not break the backward capability, the f_flags is set to O_RDWR if the flag passed by syscall is 0. Otherwise it should be O_RDONLY or O_WRONLY. When the userspace want to modify or read the map content, it will check the file mode to see if it is allowed to make the change. Signed-off-by: Chenbo Feng <fengc@google.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-20bpf: require CAP_NET_ADMIN when using devmapJohn Fastabend
Devmap is used with XDP which requires CAP_NET_ADMIN so lets also make CAP_NET_ADMIN required to use the map. Signed-off-by: John Fastabend <john.fastabend@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>
2017-10-19bpf: fix splat for illegal devmap percpu allocationDaniel Borkmann
It was reported that syzkaller was able to trigger a splat on devmap percpu allocation due to illegal/unsupported allocation request size passed to __alloc_percpu(): [ 70.094249] illegal size (32776) or align (8) for percpu allocation [ 70.094256] ------------[ cut here ]------------ [ 70.094259] WARNING: CPU: 3 PID: 3451 at mm/percpu.c:1365 pcpu_alloc+0x96/0x630 [...] [ 70.094325] Call Trace: [ 70.094328] __alloc_percpu_gfp+0x12/0x20 [ 70.094330] dev_map_alloc+0x134/0x1e0 [ 70.094331] SyS_bpf+0x9bc/0x1610 [ 70.094333] ? selinux_task_setrlimit+0x5a/0x60 [ 70.094334] ? security_task_setrlimit+0x43/0x60 [ 70.094336] entry_SYSCALL_64_fastpath+0x1a/0xa5 This was due to too large max_entries for the map such that we surpassed the upper limit of PCPU_MIN_UNIT_SIZE. It's fine to fail naturally here, so switch to __alloc_percpu_gfp() and pass __GFP_NOWARN instead. Fixes: 11393cc9b9be ("xdp: Add batching support to redirect map") Reported-by: Mark Rutland <mark.rutland@arm.com> Reported-by: Shankara Pailoor <sp3485@columbia.edu> Reported-by: Richard Weinberger <richard@nod.at> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-18bpf: devmap: pass on return value of bpf_map_precharge_memlockTobias Klauser
If bpf_map_precharge_memlock in dev_map_alloc, -ENOMEM is returned regardless of the actual error produced by bpf_map_precharge_memlock. Fix it by passing on the error returned by bpf_map_precharge_memlock. Also return -EINVAL instead of -ENOMEM if the page count overflow check fails. This makes dev_map_alloc match the behavior of other bpf maps' alloc functions wrt. return values. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-08bpf: devmap, use cond_resched instead of cpu_relaxJohn Fastabend
Be a bit more friendly about waiting for flush bits to complete. Replace the cpu_relax() with a cond_resched(). Suggested-by: Daniel Borkmann <daniel@iogearbox.net> 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>
2017-08-23bpf: netdev is never null in __dev_map_flushDaniel Borkmann
No need to test for it in fast-path, every dev in bpf_dtab_netdev is guaranteed to be non-NULL, otherwise dev_map_update_elem() will fail in the first place. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-22bpf: minor cleanups for dev_mapDaniel Borkmann
Some minor code cleanups, while going over it I also noticed that we're accounting the bitmap only for one CPU currently, so fix that up as well. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-20bpf: fix double free from dev_map_notification()Daniel Borkmann
In the current code, dev_map_free() can still race with dev_map_notification(). In dev_map_free(), we remove dtab from the list of dtabs after we purged all entries from it. However, we don't do xchg() with NULL or the like, so the entry at that point is still pointing to the device. If a unregister notification comes in at the same time, we therefore risk a double-free, since the pointer is still present in the map, and then pushed again to __dev_map_entry_free(). All this is completely unnecessary. Just remove the dtab from the list right before the synchronize_rcu(), so all outstanding readers from the notifier list have finished by then, thus we don't need to deal with this corner case anymore and also wouldn't need to nullify dev entires. This is fine because we iterate over the map releasing all entries and therefore dev references anyway. Fixes: 4cc7b9544b9a ("bpf: devmap fix mutex in rcu critical section") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-19bpf: Allow selecting numa node during map creationMartin KaFai Lau
The current map creation API does not allow to provide the numa-node preference. The memory usually comes from where the map-creation-process is running. The performance is not ideal if the bpf_prog is known to always run in a numa node different from the map-creation-process. One of the use case is sharding on CPU to different LRU maps (i.e. an array of LRU maps). Here is the test result of map_perf_test on the INNER_LRU_HASH_PREALLOC test if we force the lru map used by CPU0 to be allocated from a remote numa node: [ The machine has 20 cores. CPU0-9 at node 0. CPU10-19 at node 1 ] ># taskset -c 10 ./map_perf_test 512 8 1260000 8000000 5:inner_lru_hash_map_perf pre-alloc 1628380 events per sec 4:inner_lru_hash_map_perf pre-alloc 1626396 events per sec 3:inner_lru_hash_map_perf pre-alloc 1626144 events per sec 6:inner_lru_hash_map_perf pre-alloc 1621657 events per sec 2:inner_lru_hash_map_perf pre-alloc 1621534 events per sec 1:inner_lru_hash_map_perf pre-alloc 1620292 events per sec 7:inner_lru_hash_map_perf pre-alloc 1613305 events per sec 0:inner_lru_hash_map_perf pre-alloc 1239150 events per sec #<<< After specifying numa node: ># taskset -c 10 ./map_perf_test 512 8 1260000 8000000 5:inner_lru_hash_map_perf pre-alloc 1629627 events per sec 3:inner_lru_hash_map_perf pre-alloc 1628057 events per sec 1:inner_lru_hash_map_perf pre-alloc 1623054 events per sec 6:inner_lru_hash_map_perf pre-alloc 1616033 events per sec 2:inner_lru_hash_map_perf pre-alloc 1614630 events per sec 4:inner_lru_hash_map_perf pre-alloc 1612651 events per sec 7:inner_lru_hash_map_perf pre-alloc 1609337 events per sec 0:inner_lru_hash_map_perf pre-alloc 1619340 events per sec #<<< This patch adds one field, numa_node, to the bpf_attr. Since numa node 0 is a valid node, a new flag BPF_F_NUMA_NODE is also added. The numa_node field is honored if and only if the BPF_F_NUMA_NODE flag is set. Numa node selection is not supported for percpu map. This patch does not change all the kmalloc. F.e. 'htab = kzalloc()' is not changed since the object is small enough to stay in the cache. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-16bpf: devmap: remove unnecessary value size checkJohn Fastabend
In the devmap alloc map logic we check to ensure that the sizeof the values are not greater than KMALLOC_MAX_SIZE. But, in the dev map case we ensure the value size is 4bytes earlier in the function because all values should be netdev ifindex values. The second check is harmless but is not needed so remove it. Signed-off-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-07bpf: devmap fix mutex in rcu critical sectionJohn Fastabend
Originally we used a mutex to protect concurrent devmap update and delete operations from racing with netdev unregister notifier callbacks. The notifier hook is needed because we increment the netdev ref count when a dev is added to the devmap. This ensures the netdev reference is valid in the datapath. However, we don't want to block unregister events, hence the initial mutex and notifier handler. The concern was in the notifier hook we search the map for dev entries that hold a refcnt on the net device being torn down. But, in order to do this we require two steps, (i) dereference the netdev: dev = rcu_dereference(map[i]) (ii) test ifindex: dev->ifindex == removing_ifindex and then finally we can swap in the NULL dev in the map via an xchg operation, xchg(map[i], NULL) The danger here is a concurrent update could run a different xchg op concurrently leading us to replace the new dev with a NULL dev incorrectly. CPU 1 CPU 2 notifier hook bpf devmap update dev = rcu_dereference(map[i]) dev = rcu_dereference(map[i]) xchg(map[i]), new_dev); rcu_call(dev,...) xchg(map[i], NULL) The above flow would create the incorrect state with the dev reference in the update path being lost. To resolve this the original code used a mutex around the above block. However, updates, deletes, and lookups occur inside rcu critical sections so we can't use a mutex in this context safely. Fortunately, by writing slightly better code we can avoid the mutex altogether. If CPU 1 in the above example uses a cmpxchg and _only_ replaces the dev reference in the map when it is in fact the expected dev the race is removed completely. The two cases being illustrated here, first the race condition, CPU 1 CPU 2 notifier hook bpf devmap update dev = rcu_dereference(map[i]) dev = rcu_dereference(map[i]) xchg(map[i]), new_dev); rcu_call(dev,...) odev = cmpxchg(map[i], dev, NULL) Now we can test the cmpxchg return value, detect odev != dev and abort. Or in the good case, CPU 1 CPU 2 notifier hook bpf devmap update dev = rcu_dereference(map[i]) odev = cmpxchg(map[i], dev, NULL) [...] Now 'odev == dev' and we can do proper cleanup. And viola the original race we tried to solve with a mutex is corrected and the trace noted by Sasha below is resolved due to removal of the mutex. Note: When walking the devmap and removing dev references as needed we depend on the core to fail any calls to dev_get_by_index() using the ifindex of the device being removed. This way we do not race with the user while searching the devmap. Additionally, the mutex was also protecting list add/del/read on the list of maps in-use. This patch converts this to an RCU list and spinlock implementation. This protects the list from concurrent alloc/free operations. The notifier hook walks this list so it uses RCU read semantics. BUG: sleeping function called from invalid context at kernel/locking/mutex.c:747 in_atomic(): 1, irqs_disabled(): 0, pid: 16315, name: syz-executor1 1 lock held by syz-executor1/16315: #0: (rcu_read_lock){......}, at: [<ffffffff8c363bc2>] map_delete_elem kernel/bpf/syscall.c:577 [inline] #0: (rcu_read_lock){......}, at: [<ffffffff8c363bc2>] SYSC_bpf kernel/bpf/syscall.c:1427 [inline] #0: (rcu_read_lock){......}, at: [<ffffffff8c363bc2>] SyS_bpf+0x1d32/0x4ba0 kernel/bpf/syscall.c:1388 Fixes: 2ddf71e23cc2 ("net: add notifier hooks for devmap bpf map") Reported-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-24bpf: dev_map_alloc() shouldn't return NULLDan Carpenter
We forgot to set the error code on two error paths which means that we return ERR_PTR(0) which is NULL. The caller, find_and_alloc_map(), is not expecting that and will have a NULL dereference. Fixes: 546ac1ffb70d ("bpf: add devmap, a map for storing net device references") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-17net: add notifier hooks for devmap bpf mapJohn Fastabend
The BPF map devmap holds a refcnt on the net_device structure when it is in the map. We need to do this to ensure on driver unload we don't lose a dev reference. However, its not very convenient to have to manually unload the map when destroying a net device so add notifier handlers to do the cleanup automatically. But this creates a race between update/destroy BPF syscall and programs and the unregister netdev hook. Unfortunately, the best I could come up with is either to live with requiring manual removal of net devices from the map before removing the net device OR to add a mutex in devmap to ensure the map is not modified while we are removing a device. The fallout also requires that BPF programs no longer update/delete the map from the BPF program side because the mutex may sleep and this can not be done from inside an rcu critical section. This is not a real problem though because I have not come up with any use cases where this is actually useful in practice. If/when we come up with a compelling user for this we may need to revisit this. Signed-off-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-17xdp: Add batching support to redirect mapJohn Fastabend
For performance reasons we want to avoid updating the tail pointer in the driver tx ring as much as possible. To accomplish this we add batching support to the redirect path in XDP. This adds another ndo op "xdp_flush" that is used to inform the driver that it should bump the tail pointer on the TX ring. Signed-off-by: John Fastabend <john.fastabend@gmail.com> 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>
2017-07-17bpf: add bpf_redirect_map helper routineJohn Fastabend
BPF programs can use the devmap with a bpf_redirect_map() helper routine to forward packets to netdevice in map. Signed-off-by: John Fastabend <john.fastabend@gmail.com> 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>
2017-07-17bpf: add devmap, a map for storing net device referencesJohn Fastabend
Device map (devmap) is a BPF map, primarily useful for networking applications, that uses a key to lookup a reference to a netdevice. The map provides a clean way for BPF programs to build virtual port to physical port maps. Additionally, it provides a scoping function for the redirect action itself allowing multiple optimizations. Future patches will leverage the map to provide batching at the XDP layer. Another optimization/feature, that is not yet implemented, would be to support multiple netdevices per key to support efficient multicast and broadcast support. Signed-off-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>