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When running with conntrack rules, the dropped overlap fragments may cause
EPERM to be returned to sendto. Instead of completely failing, just ignore
those errors and continue. If this causes packets with overlap fragments to
be dropped as expected, that is okay. And if it causes packets that are
expected to be received to be dropped, which should not happen, it will be
detected as failure.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When using make kselftest TARGETS=bpf, tools/bpf is built with
MAKEFLAGS=rR, which causes $(CXX) to be undefined, which in turn causes
the build to fail with
CXX test_cpp
/bin/sh: 2: g: not found
Fix by adding a default $(CXX) value, like tools/build/feature/Makefile
already does.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200602175649.2501580-3-iii@linux.ibm.com
Since commit 0ebeea8ca8a4 ("bpf: Restrict bpf_probe_read{, str}() only to
archs where they work") 44 verifier tests fail on s390 due to not having
bpf_probe_read anymore. Fix by using bpf_probe_read_kernel.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200602174448.2501214-1-iii@linux.ibm.com
Adjust verifier test due to addition of new field.
Fixes: c3c16f2ea6d2 ("bpf: Add rx_queue_mapping to bpf_sock")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make sample_cnt volatile to fix possible selftests failure due to compiler
optimization preventing latest sample_cnt value to be visible to main thread.
sample_cnt is incremented in background thread, which is then joined into main
thread. So in terms of visibility sample_cnt update is ok. But because it's
not volatile, compiler might make optimizations that would prevent main thread
to see latest updated value. Fix this by marking global variable volatile.
Fixes: cb1c9ddd5525 ("selftests/bpf: Add BPF ringbuf selftests")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200602050349.215037-1-andriin@fb.com
Adapt bpf_skb_adjust_room() to pass in BPF_F_ADJ_ROOM_NO_CSUM_RESET flag and
use the new bpf_csum_level() helper to inc/dec the checksum level by one after
the encap/decap.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Lorenz Bauer <lmb@cloudflare.com>
Link: https://lore.kernel.org/bpf/e7458f10e3f3d795307cbc5ad870112671d9c6f7.1591108731.git.daniel@iogearbox.net
Extend the existing flow_dissector test case to run tests once using direct
prog attachments, and then for the second time using indirect attachment
via link.
The intention is to exercises the newly added high-level API for attaching
programs to network namespace with links (bpf_program__attach_netns).
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200531082846.2117903-13-jakub@cloudflare.com
Switch flow dissector test setup from custom BPF object loader to BPF
skeleton to save boilerplate and prepare for testing higher-level API for
attaching flow dissector with bpf_link.
To avoid depending on program order in the BPF object when populating the
flow dissector PROG_ARRAY map, change the program section names to contain
the program index into the map. This follows the example set by tailcall
tests.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200531082846.2117903-12-jakub@cloudflare.com
test_flow_dissector leaves a TAP device after it's finished, potentially
interfering with other tests that will run after it. Fix it by closing the
TAP descriptor on cleanup.
Fixes: 0905beec9f52 ("selftests/bpf: run flow dissector tests in skb-less mode")
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200531082846.2117903-11-jakub@cloudflare.com
Extend the existing test case for flow dissector attaching to cover:
- link creation,
- link updates,
- link info querying,
- mixing links with direct prog attachment.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200531082846.2117903-10-jakub@cloudflare.com
This test intended to verify if SO_BINDTODEVICE option works in
bpf_setsockopt. Because we already in the SOL_SOCKET level in this
connect bpf prog its safe to verify the sanity in the beginning of
the connect_v4_prog by calling the bind_to_device test helper.
The testing environment already created by the test_sock_addr.sh
script so this test assume that two netdevices already existing in
the system: veth pair with names test_sock_addr1 and test_sock_addr2.
The test will try to bind the socket to those devices first.
Then the test assume there are no netdevice with "nonexistent_dev"
name so the bpf_setsockopt will give use ENODEV error.
At the end the test remove the device binding from the socket
by binding it to an empty name.
Signed-off-by: Ferenc Fejes <fejes@inf.elte.hu>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/3f055b8e45c65639c5c73d0b4b6c589e60b86f15.1590871065.git.fejes@inf.elte.hu
This adds a test for bpf ingress policy. To ensure data writes happen
as expected with extra TLS headers we run these tests with data
verification enabled by default. This will test receive packets have
"PASS" stamped into the front of the payload.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/159079363965.5745.3390806911628980210.stgit@john-Precision-5820-Tower
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add tests to verify ability to add an XDP program to a
entry in a DEVMAP.
Add negative tests to show DEVMAP programs can not be
attached to devices as a normal XDP program, and accesses
to egress_ifindex require BPF_XDP_DEVMAP attach type.
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200529220716.75383-6-dsahern@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Extend bench framework with ability to have benchmark-provided child argument
parser for custom benchmark-specific parameters. This makes bench generic code
modular and independent from any specific benchmark.
Also implement a set of benchmarks for new BPF ring buffer and existing perf
buffer. 4 benchmarks were implemented: 2 variations for each of BPF ringbuf
and perfbuf:,
- rb-libbpf utilizes stock libbpf ring_buffer manager for reading data;
- rb-custom implements custom ring buffer setup and reading code, to
eliminate overheads inherent in generic libbpf code due to callback
functions and the need to update consumer position after each consumed
record, instead of batching updates (due to pessimistic assumption that
user callback might take long time and thus could unnecessarily hold ring
buffer space for too long);
- pb-libbpf uses stock libbpf perf_buffer code with all the default
settings, though uses higher-performance raw event callback to minimize
unnecessary overhead;
- pb-custom implements its own custom consumer code to minimize any possible
overhead of generic libbpf implementation and indirect function calls.
All of the test support default, no data notification skipped, mode, as well
as sampled mode (with --rb-sampled flag), which allows to trigger epoll
notification less frequently and reduce overhead. As will be shown, this mode
is especially critical for perf buffer, which suffers from high overhead of
wakeups in kernel.
Otherwise, all benchamrks implement similar way to generate a batch of records
by using fentry/sys_getpgid BPF program, which pushes a bunch of records in
a tight loop and records number of successful and dropped samples. Each record
is a small 8-byte integer, to minimize the effect of memory copying with
bpf_perf_event_output() and bpf_ringbuf_output().
Benchmarks that have only one producer implement optional back-to-back mode,
in which record production and consumption is alternating on the same CPU.
This is the highest-throughput happy case, showing ultimate performance
achievable with either BPF ringbuf or perfbuf.
All the below scenarios are implemented in a script in
benchs/run_bench_ringbufs.sh. Tests were performed on 28-core/56-thread
Intel Xeon CPU E5-2680 v4 @ 2.40GHz CPU.
Single-producer, parallel producer
==================================
rb-libbpf 12.054 ± 0.320M/s (drops 0.000 ± 0.000M/s)
rb-custom 8.158 ± 0.118M/s (drops 0.001 ± 0.003M/s)
pb-libbpf 0.931 ± 0.007M/s (drops 0.000 ± 0.000M/s)
pb-custom 0.965 ± 0.003M/s (drops 0.000 ± 0.000M/s)
Single-producer, parallel producer, sampled notification
========================================================
rb-libbpf 11.563 ± 0.067M/s (drops 0.000 ± 0.000M/s)
rb-custom 15.895 ± 0.076M/s (drops 0.000 ± 0.000M/s)
pb-libbpf 9.889 ± 0.032M/s (drops 0.000 ± 0.000M/s)
pb-custom 9.866 ± 0.028M/s (drops 0.000 ± 0.000M/s)
Single producer on one CPU, consumer on another one, both running at full
speed. Curiously, rb-libbpf has higher throughput than objectively faster (due
to more lightweight consumer code path) rb-custom. It appears that faster
consumer causes kernel to send notifications more frequently, because consumer
appears to be caught up more frequently. Performance of perfbuf suffers from
default "no sampling" policy and huge overhead that causes.
In sampled mode, rb-custom is winning very significantly eliminating too
frequent in-kernel wakeups, the gain appears to be more than 2x.
Perf buffer achieves even more impressive wins, compared to stock perfbuf
settings, with 10x improvements in throughput with 1:500 sampling rate. The
trade-off is that with sampling, application might not get next X events until
X+1st arrives, which is not always acceptable. With steady influx of events,
though, this shouldn't be a problem.
Overall, single-producer performance of ring buffers seems to be better no
matter the sampled/non-sampled modes, but it especially beats ring buffer
without sampling due to its adaptive notification approach.
Single-producer, back-to-back mode
==================================
rb-libbpf 15.507 ± 0.247M/s (drops 0.000 ± 0.000M/s)
rb-libbpf-sampled 14.692 ± 0.195M/s (drops 0.000 ± 0.000M/s)
rb-custom 21.449 ± 0.157M/s (drops 0.000 ± 0.000M/s)
rb-custom-sampled 20.024 ± 0.386M/s (drops 0.000 ± 0.000M/s)
pb-libbpf 1.601 ± 0.015M/s (drops 0.000 ± 0.000M/s)
pb-libbpf-sampled 8.545 ± 0.064M/s (drops 0.000 ± 0.000M/s)
pb-custom 1.607 ± 0.022M/s (drops 0.000 ± 0.000M/s)
pb-custom-sampled 8.988 ± 0.144M/s (drops 0.000 ± 0.000M/s)
Here we test a back-to-back mode, which is arguably best-case scenario both
for BPF ringbuf and perfbuf, because there is no contention and for ringbuf
also no excessive notification, because consumer appears to be behind after
the first record. For ringbuf, custom consumer code clearly wins with 21.5 vs
16 million records per second exchanged between producer and consumer. Sampled
mode actually hurts a bit due to slightly slower producer logic (it needs to
fetch amount of data available to decide whether to skip or force notification).
Perfbuf with wakeup sampling gets 5.5x throughput increase, compared to
no-sampling version. There also doesn't seem to be noticeable overhead from
generic libbpf handling code.
Perfbuf back-to-back, effect of sample rate
===========================================
pb-sampled-1 1.035 ± 0.012M/s (drops 0.000 ± 0.000M/s)
pb-sampled-5 3.476 ± 0.087M/s (drops 0.000 ± 0.000M/s)
pb-sampled-10 5.094 ± 0.136M/s (drops 0.000 ± 0.000M/s)
pb-sampled-25 7.118 ± 0.153M/s (drops 0.000 ± 0.000M/s)
pb-sampled-50 8.169 ± 0.156M/s (drops 0.000 ± 0.000M/s)
pb-sampled-100 8.887 ± 0.136M/s (drops 0.000 ± 0.000M/s)
pb-sampled-250 9.180 ± 0.209M/s (drops 0.000 ± 0.000M/s)
pb-sampled-500 9.353 ± 0.281M/s (drops 0.000 ± 0.000M/s)
pb-sampled-1000 9.411 ± 0.217M/s (drops 0.000 ± 0.000M/s)
pb-sampled-2000 9.464 ± 0.167M/s (drops 0.000 ± 0.000M/s)
pb-sampled-3000 9.575 ± 0.273M/s (drops 0.000 ± 0.000M/s)
This benchmark shows the effect of event sampling for perfbuf. Back-to-back
mode for highest throughput. Just doing every 5th record notification gives
3.5x speed up. 250-500 appears to be the point of diminishing return, with
almost 9x speed up. Most benchmarks use 500 as the default sampling for pb-raw
and pb-custom.
Ringbuf back-to-back, effect of sample rate
===========================================
rb-sampled-1 1.106 ± 0.010M/s (drops 0.000 ± 0.000M/s)
rb-sampled-5 4.746 ± 0.149M/s (drops 0.000 ± 0.000M/s)
rb-sampled-10 7.706 ± 0.164M/s (drops 0.000 ± 0.000M/s)
rb-sampled-25 12.893 ± 0.273M/s (drops 0.000 ± 0.000M/s)
rb-sampled-50 15.961 ± 0.361M/s (drops 0.000 ± 0.000M/s)
rb-sampled-100 18.203 ± 0.445M/s (drops 0.000 ± 0.000M/s)
rb-sampled-250 19.962 ± 0.786M/s (drops 0.000 ± 0.000M/s)
rb-sampled-500 20.881 ± 0.551M/s (drops 0.000 ± 0.000M/s)
rb-sampled-1000 21.317 ± 0.532M/s (drops 0.000 ± 0.000M/s)
rb-sampled-2000 21.331 ± 0.535M/s (drops 0.000 ± 0.000M/s)
rb-sampled-3000 21.688 ± 0.392M/s (drops 0.000 ± 0.000M/s)
Similar benchmark for ring buffer also shows a great advantage (in terms of
throughput) of skipping notifications. Skipping every 5th one gives 4x boost.
Also similar to perfbuf case, 250-500 seems to be the point of diminishing
returns, giving roughly 20x better results.
Keep in mind, for this test, notifications are controlled manually with
BPF_RB_NO_WAKEUP and BPF_RB_FORCE_WAKEUP. As can be seen from previous
benchmarks, adaptive notifications based on consumer's positions provides same
(or even slightly better due to simpler load generator on BPF side) benefits in
favorable back-to-back scenario. Over zealous and fast consumer, which is
almost always caught up, will make thoughput numbers smaller. That's the case
when manual notification control might prove to be extremely beneficial.
Ringbuf back-to-back, reserve+commit vs output
==============================================
reserve 22.819 ± 0.503M/s (drops 0.000 ± 0.000M/s)
output 18.906 ± 0.433M/s (drops 0.000 ± 0.000M/s)
Ringbuf sampled, reserve+commit vs output
=========================================
reserve-sampled 15.350 ± 0.132M/s (drops 0.000 ± 0.000M/s)
output-sampled 14.195 ± 0.144M/s (drops 0.000 ± 0.000M/s)
BPF ringbuf supports two sets of APIs with various usability and performance
tradeoffs: bpf_ringbuf_reserve()+bpf_ringbuf_commit() vs bpf_ringbuf_output().
This benchmark clearly shows superiority of reserve+commit approach, despite
using a small 8-byte record size.
Single-producer, consumer/producer competing on the same CPU, low batch count
=============================================================================
rb-libbpf 3.045 ± 0.020M/s (drops 3.536 ± 0.148M/s)
rb-custom 3.055 ± 0.022M/s (drops 3.893 ± 0.066M/s)
pb-libbpf 1.393 ± 0.024M/s (drops 0.000 ± 0.000M/s)
pb-custom 1.407 ± 0.016M/s (drops 0.000 ± 0.000M/s)
This benchmark shows one of the worst-case scenarios, in which producer and
consumer do not coordinate *and* fight for the same CPU. No batch count and
sampling settings were able to eliminate drops for ringbuffer, producer is
just too fast for consumer to keep up. But ringbuf and perfbuf still able to
pass through quite a lot of messages, which is more than enough for a lot of
applications.
Ringbuf, multi-producer contention
==================================
rb-libbpf nr_prod 1 10.916 ± 0.399M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 2 4.931 ± 0.030M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 3 4.880 ± 0.006M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 4 3.926 ± 0.004M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 8 4.011 ± 0.004M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 12 3.967 ± 0.016M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 16 2.604 ± 0.030M/s (drops 0.001 ± 0.002M/s)
rb-libbpf nr_prod 20 2.233 ± 0.003M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 24 2.085 ± 0.015M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 28 2.055 ± 0.004M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 32 1.962 ± 0.004M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 36 2.089 ± 0.005M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 40 2.118 ± 0.006M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 44 2.105 ± 0.004M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 48 2.120 ± 0.058M/s (drops 0.000 ± 0.001M/s)
rb-libbpf nr_prod 52 2.074 ± 0.024M/s (drops 0.007 ± 0.014M/s)
Ringbuf uses a very short-duration spinlock during reservation phase, to check
few invariants, increment producer count and set record header. This is the
biggest point of contention for ringbuf implementation. This benchmark
evaluates the effect of multiple competing writers on overall throughput of
a single shared ringbuffer.
Overall throughput drops almost 2x when going from single to two
highly-contended producers, gradually dropping with additional competing
producers. Performance drop stabilizes at around 20 producers and hovers
around 2mln even with 50+ fighting producers, which is a 5x drop compared to
non-contended case. Good kernel implementation in kernel helps maintain decent
performance here.
Note, that in the intended real-world scenarios, it's not expected to get even
close to such a high levels of contention. But if contention will become
a problem, there is always an option of sharding few ring buffers across a set
of CPUs.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200529075424.3139988-5-andriin@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Both singleton BPF ringbuf and BPF ringbuf with map-in-map use cases are tested.
Also reserve+submit/discards and output variants of API are validated.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200529075424.3139988-4-andriin@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit adds a new MPSC ring buffer implementation into BPF ecosystem,
which allows multiple CPUs to submit data to a single shared ring buffer. On
the consumption side, only single consumer is assumed.
Motivation
----------
There are two distinctive motivators for this work, which are not satisfied by
existing perf buffer, which prompted creation of a new ring buffer
implementation.
- more efficient memory utilization by sharing ring buffer across CPUs;
- preserving ordering of events that happen sequentially in time, even
across multiple CPUs (e.g., fork/exec/exit events for a task).
These two problems are independent, but perf buffer fails to satisfy both.
Both are a result of a choice to have per-CPU perf ring buffer. Both can be
also solved by having an MPSC implementation of ring buffer. The ordering
problem could technically be solved for perf buffer with some in-kernel
counting, but given the first one requires an MPSC buffer, the same solution
would solve the second problem automatically.
Semantics and APIs
------------------
Single ring buffer is presented to BPF programs as an instance of BPF map of
type BPF_MAP_TYPE_RINGBUF. Two other alternatives considered, but ultimately
rejected.
One way would be to, similar to BPF_MAP_TYPE_PERF_EVENT_ARRAY, make
BPF_MAP_TYPE_RINGBUF could represent an array of ring buffers, but not enforce
"same CPU only" rule. This would be more familiar interface compatible with
existing perf buffer use in BPF, but would fail if application needed more
advanced logic to lookup ring buffer by arbitrary key. HASH_OF_MAPS addresses
this with current approach. Additionally, given the performance of BPF
ringbuf, many use cases would just opt into a simple single ring buffer shared
among all CPUs, for which current approach would be an overkill.
Another approach could introduce a new concept, alongside BPF map, to
represent generic "container" object, which doesn't necessarily have key/value
interface with lookup/update/delete operations. This approach would add a lot
of extra infrastructure that has to be built for observability and verifier
support. It would also add another concept that BPF developers would have to
familiarize themselves with, new syntax in libbpf, etc. But then would really
provide no additional benefits over the approach of using a map.
BPF_MAP_TYPE_RINGBUF doesn't support lookup/update/delete operations, but so
doesn't few other map types (e.g., queue and stack; array doesn't support
delete, etc).
The approach chosen has an advantage of re-using existing BPF map
infrastructure (introspection APIs in kernel, libbpf support, etc), being
familiar concept (no need to teach users a new type of object in BPF program),
and utilizing existing tooling (bpftool). For common scenario of using
a single ring buffer for all CPUs, it's as simple and straightforward, as
would be with a dedicated "container" object. On the other hand, by being
a map, it can be combined with ARRAY_OF_MAPS and HASH_OF_MAPS map-in-maps to
implement a wide variety of topologies, from one ring buffer for each CPU
(e.g., as a replacement for perf buffer use cases), to a complicated
application hashing/sharding of ring buffers (e.g., having a small pool of
ring buffers with hashed task's tgid being a look up key to preserve order,
but reduce contention).
Key and value sizes are enforced to be zero. max_entries is used to specify
the size of ring buffer and has to be a power of 2 value.
There are a bunch of similarities between perf buffer
(BPF_MAP_TYPE_PERF_EVENT_ARRAY) and new BPF ring buffer semantics:
- variable-length records;
- if there is no more space left in ring buffer, reservation fails, no
blocking;
- memory-mappable data area for user-space applications for ease of
consumption and high performance;
- epoll notifications for new incoming data;
- but still the ability to do busy polling for new data to achieve the
lowest latency, if necessary.
BPF ringbuf provides two sets of APIs to BPF programs:
- bpf_ringbuf_output() allows to *copy* data from one place to a ring
buffer, similarly to bpf_perf_event_output();
- bpf_ringbuf_reserve()/bpf_ringbuf_commit()/bpf_ringbuf_discard() APIs
split the whole process into two steps. First, a fixed amount of space is
reserved. If successful, a pointer to a data inside ring buffer data area
is returned, which BPF programs can use similarly to a data inside
array/hash maps. Once ready, this piece of memory is either committed or
discarded. Discard is similar to commit, but makes consumer ignore the
record.
bpf_ringbuf_output() has disadvantage of incurring extra memory copy, because
record has to be prepared in some other place first. But it allows to submit
records of the length that's not known to verifier beforehand. It also closely
matches bpf_perf_event_output(), so will simplify migration significantly.
bpf_ringbuf_reserve() avoids the extra copy of memory by providing a memory
pointer directly to ring buffer memory. In a lot of cases records are larger
than BPF stack space allows, so many programs have use extra per-CPU array as
a temporary heap for preparing sample. bpf_ringbuf_reserve() avoid this needs
completely. But in exchange, it only allows a known constant size of memory to
be reserved, such that verifier can verify that BPF program can't access
memory outside its reserved record space. bpf_ringbuf_output(), while slightly
slower due to extra memory copy, covers some use cases that are not suitable
for bpf_ringbuf_reserve().
The difference between commit and discard is very small. Discard just marks
a record as discarded, and such records are supposed to be ignored by consumer
code. Discard is useful for some advanced use-cases, such as ensuring
all-or-nothing multi-record submission, or emulating temporary malloc()/free()
within single BPF program invocation.
Each reserved record is tracked by verifier through existing
reference-tracking logic, similar to socket ref-tracking. It is thus
impossible to reserve a record, but forget to submit (or discard) it.
bpf_ringbuf_query() helper allows to query various properties of ring buffer.
Currently 4 are supported:
- BPF_RB_AVAIL_DATA returns amount of unconsumed data in ring buffer;
- BPF_RB_RING_SIZE returns the size of ring buffer;
- BPF_RB_CONS_POS/BPF_RB_PROD_POS returns current logical possition of
consumer/producer, respectively.
Returned values are momentarily snapshots of ring buffer state and could be
off by the time helper returns, so this should be used only for
debugging/reporting reasons or for implementing various heuristics, that take
into account highly-changeable nature of some of those characteristics.
One such heuristic might involve more fine-grained control over poll/epoll
notifications about new data availability in ring buffer. Together with
BPF_RB_NO_WAKEUP/BPF_RB_FORCE_WAKEUP flags for output/commit/discard helpers,
it allows BPF program a high degree of control and, e.g., more efficient
batched notifications. Default self-balancing strategy, though, should be
adequate for most applications and will work reliable and efficiently already.
Design and implementation
-------------------------
This reserve/commit schema allows a natural way for multiple producers, either
on different CPUs or even on the same CPU/in the same BPF program, to reserve
independent records and work with them without blocking other producers. This
means that if BPF program was interruped by another BPF program sharing the
same ring buffer, they will both get a record reserved (provided there is
enough space left) and can work with it and submit it independently. This
applies to NMI context as well, except that due to using a spinlock during
reservation, in NMI context, bpf_ringbuf_reserve() might fail to get a lock,
in which case reservation will fail even if ring buffer is not full.
The ring buffer itself internally is implemented as a power-of-2 sized
circular buffer, with two logical and ever-increasing counters (which might
wrap around on 32-bit architectures, that's not a problem):
- consumer counter shows up to which logical position consumer consumed the
data;
- producer counter denotes amount of data reserved by all producers.
Each time a record is reserved, producer that "owns" the record will
successfully advance producer counter. At that point, data is still not yet
ready to be consumed, though. Each record has 8 byte header, which contains
the length of reserved record, as well as two extra bits: busy bit to denote
that record is still being worked on, and discard bit, which might be set at
commit time if record is discarded. In the latter case, consumer is supposed
to skip the record and move on to the next one. Record header also encodes
record's relative offset from the beginning of ring buffer data area (in
pages). This allows bpf_ringbuf_commit()/bpf_ringbuf_discard() to accept only
the pointer to the record itself, without requiring also the pointer to ring
buffer itself. Ring buffer memory location will be restored from record
metadata header. This significantly simplifies verifier, as well as improving
API usability.
Producer counter increments are serialized under spinlock, so there is
a strict ordering between reservations. Commits, on the other hand, are
completely lockless and independent. All records become available to consumer
in the order of reservations, but only after all previous records where
already committed. It is thus possible for slow producers to temporarily hold
off submitted records, that were reserved later.
Reservation/commit/consumer protocol is verified by litmus tests in
Documentation/litmus-test/bpf-rb.
One interesting implementation bit, that significantly simplifies (and thus
speeds up as well) implementation of both producers and consumers is how data
area is mapped twice contiguously back-to-back in the virtual memory. This
allows to not take any special measures for samples that have to wrap around
at the end of the circular buffer data area, because the next page after the
last data page would be first data page again, and thus the sample will still
appear completely contiguous in virtual memory. See comment and a simple ASCII
diagram showing this visually in bpf_ringbuf_area_alloc().
Another feature that distinguishes BPF ringbuf from perf ring buffer is
a self-pacing notifications of new data being availability.
bpf_ringbuf_commit() implementation will send a notification of new record
being available after commit only if consumer has already caught up right up
to the record being committed. If not, consumer still has to catch up and thus
will see new data anyways without needing an extra poll notification.
Benchmarks (see tools/testing/selftests/bpf/benchs/bench_ringbuf.c) show that
this allows to achieve a very high throughput without having to resort to
tricks like "notify only every Nth sample", which are necessary with perf
buffer. For extreme cases, when BPF program wants more manual control of
notifications, commit/discard/output helpers accept BPF_RB_NO_WAKEUP and
BPF_RB_FORCE_WAKEUP flags, which give full control over notifications of data
availability, but require extra caution and diligence in using this API.
Comparison to alternatives
--------------------------
Before considering implementing BPF ring buffer from scratch existing
alternatives in kernel were evaluated, but didn't seem to meet the needs. They
largely fell into few categores:
- per-CPU buffers (perf, ftrace, etc), which don't satisfy two motivations
outlined above (ordering and memory consumption);
- linked list-based implementations; while some were multi-producer designs,
consuming these from user-space would be very complicated and most
probably not performant; memory-mapping contiguous piece of memory is
simpler and more performant for user-space consumers;
- io_uring is SPSC, but also requires fixed-sized elements. Naively turning
SPSC queue into MPSC w/ lock would have subpar performance compared to
locked reserve + lockless commit, as with BPF ring buffer. Fixed sized
elements would be too limiting for BPF programs, given existing BPF
programs heavily rely on variable-sized perf buffer already;
- specialized implementations (like a new printk ring buffer, [0]) with lots
of printk-specific limitations and implications, that didn't seem to fit
well for intended use with BPF programs.
[0] https://lwn.net/Articles/779550/
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200529075424.3139988-2-andriin@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
For write-only stacks and queues bpf_map_update_elem should be allowed, but
bpf_map_lookup_elem and bpf_map_lookup_and_delete_elem should fail with EPERM.
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200527185700.14658-6-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make comments inside the test_map_rdonly and test_map_wronly tests
consistent with logic.
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200527185700.14658-4-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The test_map_rdonly and test_map_wronly tests should close file descriptors
which they open.
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200527185700.14658-3-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Trivial fix to a typo in the test_map_wronly test: "read" -> "write"
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200527185700.14658-2-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Lets test using probe* in SCHED_CLS network programs as well just
to be sure these keep working. Its cheap to add the extra test
and provides a second context to test outside of sk_msg after
we generalized probe* helpers to all networking types.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/159033911685.12355.15951980509828906214.stgit@john-Precision-5820-Tower
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The test itself is not particularly useful but it encodes a common
pattern we have.
Namely do a sk storage lookup then depending on data here decide if
we need to do more work or alternatively allow packet to PASS. Then
if we need to do more work consult task_struct for more information
about the running task. Finally based on this additional information
drop or pass the data. In this case the suspicious check is not so
realisitic but it encodes the general pattern and uses the helpers
so we test the workflow.
This is a load test to ensure verifier correctly handles this case.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/159033909665.12355.6166415847337547879.stgit@john-Precision-5820-Tower
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Generate packets matching the various control traps and check that the
traps' stats increase accordingly.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
xdp_umem.c had overlapping changes between the 64-bit math fix
for the calculation of npgs and the removal of the zerocopy
memory type which got rid of the chunk_size_nohdr member.
The mlx5 Kconfig conflict is a case where we just take the
net-next copy of the Kconfig entry dependency as it takes on
the ESWITCH dependency by one level of indirection which is
what the 'net' conflicting change is trying to ensure.
Signed-off-by: David S. Miller <davem@davemloft.net>
A missing stats_update callback was recently added to act_pedit. Now that
iproute2 supports JSON dumping for pedit, extend the pedit_dsfield selftest
with a check that would have caught the fact that the callback was missing.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using ping in tests is error-prone, because ping is too smart. On a
flaky system (notably in a simulator), when packets don't come quickly
enough, more pings are sent, and that throws off counters. Instead use
mausezahn to generate ICMP echo request packets. That allows us to
send them in quicker succession as well, because the reason the ping
was made slow in the first place was to make the tests work on
simulated systems.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov says:
====================
pull-request: bpf 2020-05-29
The following pull-request contains BPF updates for your *net* tree.
We've added 6 non-merge commits during the last 7 day(s) which contain
a total of 4 files changed, 55 insertions(+), 34 deletions(-).
The main changes are:
1) minor verifier fix for fmod_ret progs, from Alexei.
2) af_xdp overflow check, from Bjorn.
3) minor verifier fix for 32bit assignment, from John.
4) powerpc has non-overlapping addr space, from Petr.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Added a verifier test for assigning 32bit reg states to
64bit where 32bit reg holds a constant value of 0.
Without previous kernel verifier.c fix, the test in
this patch will fail.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/159077335867.6014.2075350327073125374.stgit@john-Precision-5820-Tower
After previous fix for zero extension test_verifier tests #65 and #66 now
fail. Before the fix we can see the alu32 mov op at insn 10
10: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0)
R1_w=invP(id=0,
smin_value=4294967168,smax_value=4294967423,
umin_value=4294967168,umax_value=4294967423,
var_off=(0x0; 0x1ffffffff),
s32_min_value=-2147483648,s32_max_value=2147483647,
u32_min_value=0,u32_max_value=-1)
R10=fp0 fp-8_w=mmmmmmmm
10: (bc) w1 = w1
11: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0)
R1_w=invP(id=0,
smin_value=0,smax_value=2147483647,
umin_value=0,umax_value=4294967295,
var_off=(0x0; 0xffffffff),
s32_min_value=-2147483648,s32_max_value=2147483647,
u32_min_value=0,u32_max_value=-1)
R10=fp0 fp-8_w=mmmmmmmm
After the fix at insn 10 because we have 's32_min_value < 0' the following
step 11 now has 'smax_value=U32_MAX' where before we pulled the s32_max_value
bound into the smax_value as seen above in 11 with smax_value=2147483647.
10: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0)
R1_w=inv(id=0,
smin_value=4294967168,smax_value=4294967423,
umin_value=4294967168,umax_value=4294967423,
var_off=(0x0; 0x1ffffffff),
s32_min_value=-2147483648, s32_max_value=2147483647,
u32_min_value=0,u32_max_value=-1)
R10=fp0 fp-8_w=mmmmmmmm
10: (bc) w1 = w1
11: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0)
R1_w=inv(id=0,
smin_value=0,smax_value=4294967295,
umin_value=0,umax_value=4294967295,
var_off=(0x0; 0xffffffff),
s32_min_value=-2147483648, s32_max_value=2147483647,
u32_min_value=0, u32_max_value=-1)
R10=fp0 fp-8_w=mmmmmmmm
The fall out of this is by the time we get to the failing instruction at
step 14 where previously we had the following:
14: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0)
R1_w=inv(id=0,
smin_value=72057594021150720,smax_value=72057594029539328,
umin_value=72057594021150720,umax_value=72057594029539328,
var_off=(0xffffffff000000; 0xffffff),
s32_min_value=-16777216,s32_max_value=-1,
u32_min_value=-16777216,u32_max_value=-1)
R10=fp0 fp-8_w=mmmmmmmm
14: (0f) r0 += r1
We now have,
14: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0)
R1_w=inv(id=0,
smin_value=0,smax_value=72057594037927935,
umin_value=0,umax_value=72057594037927935,
var_off=(0x0; 0xffffffffffffff),
s32_min_value=-2147483648,s32_max_value=2147483647,
u32_min_value=0,u32_max_value=-1)
R10=fp0 fp-8_w=mmmmmmmm
14: (0f) r0 += r1
In the original step 14 'smin_value=72057594021150720' this trips the logic
in the verifier function check_reg_sane_offset(),
if (smin >= BPF_MAX_VAR_OFF || smin <= -BPF_MAX_VAR_OFF) {
verbose(env, "value %lld makes %s pointer be out of bounds\n",
smin, reg_type_str[type]);
return false;
}
Specifically, the 'smin <= -BPF_MAX_VAR_OFF' check. But with the fix
at step 14 we have bounds 'smin_value=0' so the above check is not tripped
because BPF_MAX_VAR_OFF=1<<29.
We have a smin_value=0 here because at step 10 the smaller smin_value=0 means
the subtractions at steps 11 and 12 bring the smin_value negative.
11: (17) r1 -= 2147483584
12: (17) r1 -= 2147483584
13: (77) r1 >>= 8
Then the shift clears the top bit and smin_value is set to 0. Note we still
have the smax_value in the fixed code so any reads will fail. An alternative
would be to have reg_sane_check() do both smin and smax value tests.
To fix the test we can omit the 'r1 >>=8' at line 13. This will change the
err string, but keeps the intention of the test as suggseted by the title,
"check after truncation of boundary-crossing range". If the verifier logic
changes a different value is likely to be thrown in the error or the error
will no longer be thrown forcing this test to be examined. With this change
we see the new state at step 13.
13: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0)
R1_w=invP(id=0,
smin_value=-4294967168,smax_value=127,
umin_value=0,umax_value=18446744073709551615,
s32_min_value=-2147483648,s32_max_value=2147483647,
u32_min_value=0,u32_max_value=-1)
R10=fp0 fp-8_w=mmmmmmmm
Giving the expected out of bounds error, "value -4294967168 makes map_value
pointer be out of bounds" However, for unpriv case we see a different error
now because of the mixed signed bounds pointer arithmatic. This seems OK so
I've only added the unpriv_errstr for this. Another optino may have been to
do addition on r1 instead of subtraction but I favor the approach above
slightly.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/159077333942.6014.14004320043595756079.stgit@john-Precision-5820-Tower
Add Nik's torture tests as a new set to stress the replace and cleanup
paths.
Torture test created by Nikolay Aleksandrov and then I adapted to
selftest and added IPv6 version.
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a couple large ecmp group nexthop selftests to cover
the remnant fixed by d69100b8eee27c2d60ee52df76e0b80a8d492d34.
The tests create 100 x32 ecmp groups of ipv4 and ipv6 and then
dump them. On kernels without the fix, they will fail due
to data remnant during the dump.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To align with recent recommended values. Will be configurable by future
patches.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The MSCC bug fix in 'net' had to be slightly adjusted because the
register accesses are done slightly differently in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Fix RCU warnings in ipv6 multicast router code, from Madhuparna
Bhowmik.
2) Nexthop attributes aren't being checked properly because of
mis-initialized iterator, from David Ahern.
3) Revert iop_idents_reserve() change as it caused performance
regressions and was just working around what is really a UBSAN bug
in the compiler. From Yuqi Jin.
4) Read MAC address properly from ROM in bmac driver (double iteration
proceeds past end of address array), from Jeremy Kerr.
5) Add Microsoft Surface device IDs to r8152, from Marc Payne.
6) Prevent reference to freed SKB in __netif_receive_skb_core(), from
Boris Sukholitko.
7) Fix ACK discard behavior in rxrpc, from David Howells.
8) Preserve flow hash across packet scrubbing in wireguard, from Jason
A. Donenfeld.
9) Cap option length properly for SO_BINDTODEVICE in AX25, from Eric
Dumazet.
10) Fix encryption error checking in kTLS code, from Vadim Fedorenko.
11) Missing BPF prog ref release in flow dissector, from Jakub Sitnicki.
12) dst_cache must be used with BH disabled in tipc, from Eric Dumazet.
13) Fix use after free in mlxsw driver, from Jiri Pirko.
14) Order kTLS key destruction properly in mlx5 driver, from Tariq
Toukan.
15) Check devm_platform_ioremap_resource() return value properly in
several drivers, from Tiezhu Yang.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (71 commits)
net: smsc911x: Fix runtime PM imbalance on error
net/mlx4_core: fix a memory leak bug.
net: ethernet: ti: cpsw: fix ASSERT_RTNL() warning during suspend
net: phy: mscc: fix initialization of the MACsec protocol mode
net: stmmac: don't attach interface until resume finishes
net: Fix return value about devm_platform_ioremap_resource()
net/mlx5: Fix error flow in case of function_setup failure
net/mlx5e: CT: Correctly get flow rule
net/mlx5e: Update netdev txq on completions during closure
net/mlx5: Annotate mutex destroy for root ns
net/mlx5: Don't maintain a case of del_sw_func being null
net/mlx5: Fix cleaning unmanaged flow tables
net/mlx5: Fix memory leak in mlx5_events_init
net/mlx5e: Fix inner tirs handling
net/mlx5e: kTLS, Destroy key object after destroying the TIS
net/mlx5e: Fix allowed tc redirect merged eswitch offload cases
net/mlx5: Avoid processing commands before cmdif is ready
net/mlx5: Fix a race when moving command interface to events mode
net/mlx5: Add command entry handling completion
rxrpc: Fix a memory leak in rxkad_verify_response()
...
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-05-23
The following pull-request contains BPF updates for your *net-next* tree.
We've added 50 non-merge commits during the last 8 day(s) which contain
a total of 109 files changed, 2776 insertions(+), 2887 deletions(-).
The main changes are:
1) Add a new AF_XDP buffer allocation API to the core in order to help
lowering the bar for drivers adopting AF_XDP support. i40e, ice, ixgbe
as well as mlx5 have been moved over to the new API and also gained a
small improvement in performance, from Björn Töpel and Magnus Karlsson.
2) Add getpeername()/getsockname() attach types for BPF sock_addr programs
in order to allow for e.g. reverse translation of load-balancer backend
to service address/port tuple from a connected peer, from Daniel Borkmann.
3) Improve the BPF verifier is_branch_taken() logic to evaluate pointers
being non-NULL, e.g. if after an initial test another non-NULL test on
that pointer follows in a given path, then it can be pruned right away,
from John Fastabend.
4) Larger rework of BPF sockmap selftests to make output easier to understand
and to reduce overall runtime as well as adding new BPF kTLS selftests
that run in combination with sockmap, also from John Fastabend.
5) Batch of misc updates to BPF selftests including fixing up test_align
to match verifier output again and moving it under test_progs, allowing
bpf_iter selftest to compile on machines with older vmlinux.h, and
updating config options for lirc and v6 segment routing helpers, from
Stanislav Fomichev, Andrii Nakryiko and Alan Maguire.
6) Conversion of BPF tracing samples outdated internal BPF loader to use
libbpf API instead, from Daniel T. Lee.
7) Follow-up to BPF kernel test infrastructure in order to fix a flake in
the XDP selftests, from Jesper Dangaard Brouer.
8) Minor improvements to libbpf's internal hashmap implementation, from
Ian Rogers.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
test_lirc_mode2.sh assumes presence of /sys/class/rc/rc0/lirc*/uevent
which will not be present unless CONFIG_LIRC=y
Fixes: 6bdd533cee9a ("bpf: add selftest for lirc_mode2 type program")
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1590147389-26482-3-git-send-email-alan.maguire@oracle.com
test_seg6_loop.o uses the helper bpf_lwt_seg6_adjust_srh();
it will not be present if CONFIG_IPV6_SEG6_BPF is not specified.
Fixes: b061017f8b4d ("selftests/bpf: add realistic loop tests")
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1590147389-26482-2-git-send-email-alan.maguire@oracle.com
Getting a clean BPF selftests run involves ensuring latest trunk LLVM/clang
are used, pahole is recent (>=1.16) and config matches the specified
config file as closely as possible. Add to bpf_devel_QA.rst and point
tools/testing/selftests/bpf/README.rst to it.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/1590146674-25485-1-git-send-email-alan.maguire@oracle.com
Starting from iputils s20190709 (used in Fedora 31), arping does not
support timeout being specified as a decimal:
$ arping -c 1 -I swp1 -b 192.0.2.66 -q -w 0.1
arping: invalid argument: '0.1'
Previously, such timeouts were rounded to an integer.
Fix this by specifying the timeout as an integer.
Fixes: a5ee171d087e ("selftests: mlxsw: qos_mc_aware: Add a test for UC awareness")
Signed-off-by: Amit Cohen <amitc@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The variable is used by log_test() to check if the test case completely
successfully or not. In case it is not initialized at the start of a
test case, it is possible for the test case to fail despite not
encountering any errors.
Example:
```
...
TEST: Trap group statistics [ OK ]
TEST: Trap policer [FAIL]
Policer drop counter was not incremented
TEST: Trap policer binding [FAIL]
Policer drop counter was not incremented
```
Failure of trap_policer_test() caused trap_policer_bind_test() to fail
as well.
Fix by adding missing initialization of the variable.
Fixes: 5fbff58e27a1 ("selftests: netdevsim: Add test cases for devlink-trap policers")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf 2020-05-22
The following pull-request contains BPF updates for your *net* tree.
We've added 3 non-merge commits during the last 3 day(s) which contain
a total of 5 files changed, 69 insertions(+), 11 deletions(-).
The main changes are:
1) Fix to reject mmap()'ing read-only array maps as writable since BPF verifier
relies on such map content to be frozen, from Andrii Nakryiko.
2) Fix breaking audit from secid_to_secctx() LSM hook by avoiding to use
call_int_hook() since this hook is not stackable, from KP Singh.
3) Fix BPF flow dissector program ref leak on netns cleanup, from Jakub Sitnicki.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit adds ipv4 and ipv6 fdb nexthop api tests to fib_nexthops.sh.
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adding a printk to test_sk_lookup_kern created the reported failure
where a pointer type is checked twice for NULL. Lets add it to the
progs test test_sk_lookup_kern.c so we test the case from C all the
way into the verifier.
We already have printk's in selftests so seems OK to add another one.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/159009170603.6313.1715279795045285176.stgit@john-Precision-5820-Tower
When we have pointer type that is known to be non-null we only follow
the non-null branch. This adds tests to cover the map_value pointer
returned from a map lookup. To force an error if both branches are
followed we do an ALU op on R10.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/159009168650.6313.7434084136067263554.stgit@john-Precision-5820-Tower
When we have pointer type that is known to be non-null and comparing
against zero we only follow the non-null branch. This adds tests to
cover this case for reference tracking. Also add the other case when
comparison against a non-zero value and ensure we still fail with
unreleased reference.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/159009166599.6313.1593680633787453767.stgit@john-Precision-5820-Tower
gcc-10 switched to defaulting to -fno-common, which broke iproute2-5.4.
This was fixed in iproute-5.6, so switch to that. Because we're after a
stable testing surface, we generally don't like to bump these
unnecessarily, but in this case, being able to actually build is a basic
necessity.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As discussed in [0], it's dangerous to allow mapping BPF map, that's meant to
be frozen and is read-only on BPF program side, because that allows user-space
to actually store a writable view to the page even after it is frozen. This is
exacerbated by BPF verifier making a strong assumption that contents of such
frozen map will remain unchanged. To prevent this, disallow mapping
BPF_F_RDONLY_PROG mmap()'able BPF maps as writable, ever.
[0] https://lore.kernel.org/bpf/CAEf4BzYGWYhXdp6BJ7_=9OQPJxQpgug080MMjdSB72i9R+5c6g@mail.gmail.com/
Fixes: fc9702273e2e ("bpf: Add mmap() support for BPF_MAP_TYPE_ARRAY")
Suggested-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/bpf/20200519053824.1089415-1-andriin@fb.com
