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2020-05-14selftest/bpf: Fix spelling mistake "SIGALARM" -> "SIGALRM"Colin Ian King1-1/+1
There is a spelling mistake in an error message, fix it. Signed-off-by: Colin Ian King <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-14selftests/bpf: Test narrow loads for bpf_sock_addr.user_portAndrey Ignatov1-10/+28
Test 1,2,4-byte loads from bpf_sock_addr.user_port in sock_addr programs. Signed-off-by: Andrey Ignatov <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/e5c734a58cca4041ab30cb5471e644246f8cdb5a.1589420814.git.rdna@fb.com
2020-05-14selftests/bpf: Enforce returning 0 for fentry/fexit programsYonghong Song1-2/+2
There are a few fentry/fexit programs returning non-0. The tests with these programs will break with the previous patch which enfoced return-0 rules. Fix them properly. Fixes: ac065870d928 ("selftests/bpf: Add BPF_PROG, BPF_KPROBE, and BPF_KRETPROBE macros") Signed-off-by: Yonghong Song <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-14bpf: Fix bug in mmap() implementation for BPF array mapAndrii Nakryiko1-0/+8
mmap() subsystem allows user-space application to memory-map region with initial page offset. This wasn't taken into account in initial implementation of BPF array memory-mapping. This would result in wrong pages, not taking into account requested page shift, being memory-mmaped into user-space. This patch fixes this gap and adds a test for such scenario. Fixes: fc9702273e2e ("bpf: Add mmap() support for BPF_MAP_TYPE_ARRAY") Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-13tools/bpf: selftests : Explain bpf_iter test failures with llvm 10.0.0Yonghong Song1-0/+43
Commit 6879c042e105 ("tools/bpf: selftests: Add bpf_iter selftests") added self tests for bpf_iter feature. But two subtests ipv6_route and netlink needs llvm latest 10.x release branch or trunk due to a bug in llvm BPF backend. This patch added the file README.rst to document these two failures so people using llvm 10.0.0 can be aware of them. Suggested-by: Alexei Starovoitov <[email protected]> Signed-off-by: Yonghong Song <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-13selftest/bpf: Add BPF triggering benchmarkAndrii Nakryiko5-1/+238
It is sometimes desirable to be able to trigger BPF program from user-space with minimal overhead. sys_enter would seem to be a good candidate, yet in a lot of cases there will be a lot of noise from syscalls triggered by other processes on the system. So while searching for low-overhead alternative, I've stumbled upon getpgid() syscall, which seems to be specific enough to not suffer from accidental syscall by other apps. This set of benchmarks compares tp, raw_tp w/ filtering by syscall ID, kprobe, fentry and fmod_ret with returning error (so that syscall would not be executed), to determine the lowest-overhead way. Here are results on my machine (using benchs/run_bench_trigger.sh script): base : 9.200 ± 0.319M/s tp : 6.690 ± 0.125M/s rawtp : 8.571 ± 0.214M/s kprobe : 6.431 ± 0.048M/s fentry : 8.955 ± 0.241M/s fmodret : 8.903 ± 0.135M/s So it seems like fmodret doesn't give much benefit for such lightweight syscall. Raw tracepoint is pretty decent despite additional filtering logic, but it will be called for any other syscall in the system, which rules it out. Fentry, though, seems to be adding the least amoung of overhead and achieves 97.3% of performance of baseline no-BPF-attached syscall. Using getpgid() seems to be preferable to set_task_comm() approach from test_overhead, as it's about 2.35x faster in a baseline performance. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: John Fastabend <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-13selftest/bpf: Fmod_ret prog and implement test_overhead as part of benchAndrii Nakryiko6-2/+240
Add fmod_ret BPF program to existing test_overhead selftest. Also re-implement user-space benchmarking part into benchmark runner to compare results. Results with ./bench are consistently somewhat lower than test_overhead's, but relative performance of various types of BPF programs stay consisten (e.g., kretprobe is noticeably slower). This slowdown seems to be coming from the fact that test_overhead is single-threaded, while benchmark always spins off at least one thread for producer. This has been confirmed by hacking multi-threaded test_overhead variant and also single-threaded bench variant. Resutls are below. run_bench_rename.sh script from benchs/ subdirectory was used to produce results for ./bench. Single-threaded implementations =============================== /* bench: single-threaded, atomics */ base : 4.622 ± 0.049M/s kprobe : 3.673 ± 0.052M/s kretprobe : 2.625 ± 0.052M/s rawtp : 4.369 ± 0.089M/s fentry : 4.201 ± 0.558M/s fexit : 4.309 ± 0.148M/s fmodret : 4.314 ± 0.203M/s /* selftest: single-threaded, no atomics */ task_rename base 4555K events per sec task_rename kprobe 3643K events per sec task_rename kretprobe 2506K events per sec task_rename raw_tp 4303K events per sec task_rename fentry 4307K events per sec task_rename fexit 4010K events per sec task_rename fmod_ret 3984K events per sec Multi-threaded implementations ============================== /* bench: multi-threaded w/ atomics */ base : 3.910 ± 0.023M/s kprobe : 3.048 ± 0.037M/s kretprobe : 2.300 ± 0.015M/s rawtp : 3.687 ± 0.034M/s fentry : 3.740 ± 0.087M/s fexit : 3.510 ± 0.009M/s fmodret : 3.485 ± 0.050M/s /* selftest: multi-threaded w/ atomics */ task_rename base 3872K events per sec task_rename kprobe 3068K events per sec task_rename kretprobe 2350K events per sec task_rename raw_tp 3731K events per sec task_rename fentry 3639K events per sec task_rename fexit 3558K events per sec task_rename fmod_ret 3511K events per sec /* selftest: multi-threaded, no atomics */ task_rename base 3945K events per sec task_rename kprobe 3298K events per sec task_rename kretprobe 2451K events per sec task_rename raw_tp 3718K events per sec task_rename fentry 3782K events per sec task_rename fexit 3543K events per sec task_rename fmod_ret 3526K events per sec Note that the fact that ./bench benchmark always uses atomic increments for counting, while test_overhead doesn't, doesn't influence test results all that much. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: John Fastabend <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-13selftests/bpf: Add benchmark runner infrastructureAndrii Nakryiko5-1/+608
While working on BPF ringbuf implementation, testing, and benchmarking, I've developed a pretty generic and modular benchmark runner, which seems to be generically useful, as I've already used it for one more purpose (testing fastest way to trigger BPF program, to minimize overhead of in-kernel code). This patch adds generic part of benchmark runner and sets up Makefile for extending it with more sets of benchmarks. Benchmarker itself operates by spinning up specified number of producer and consumer threads, setting up interval timer sending SIGALARM signal to application once a second. Every second, current snapshot with hits/drops counters are collected and stored in an array. Drops are useful for producer/consumer benchmarks in which producer might overwhelm consumers. Once test finishes after given amount of warm-up and testing seconds, mean and stddev are calculated (ignoring warm-up results) and is printed out to stdout. This setup seems to give consistent and accurate results. To validate behavior, I added two atomic counting tests: global and local. For global one, all the producer threads are atomically incrementing same counter as fast as possible. This, of course, leads to huge drop of performance once there is more than one producer thread due to CPUs fighting for the same memory location. Local counting, on the other hand, maintains one counter per each producer thread, incremented independently. Once per second, all counters are read and added together to form final "counting throughput" measurement. As expected, such setup demonstrates linear scalability with number of producers (as long as there are enough physical CPU cores, of course). See example output below. Also, this setup can nicely demonstrate disastrous effects of false sharing, if care is not taken to take those per-producer counters apart into independent cache lines. Demo output shows global counter first with 1 producer, then with 4. Both total and per-producer performance significantly drop. The last run is local counter with 4 producers, demonstrating near-perfect scalability. $ ./bench -a -w1 -d2 -p1 count-global Setting up benchmark 'count-global'... Benchmark 'count-global' started. Iter 0 ( 24.822us): hits 148.179M/s (148.179M/prod), drops 0.000M/s Iter 1 ( 37.939us): hits 149.308M/s (149.308M/prod), drops 0.000M/s Iter 2 (-10.774us): hits 150.717M/s (150.717M/prod), drops 0.000M/s Iter 3 ( 3.807us): hits 151.435M/s (151.435M/prod), drops 0.000M/s Summary: hits 150.488 ± 1.079M/s (150.488M/prod), drops 0.000 ± 0.000M/s $ ./bench -a -w1 -d2 -p4 count-global Setting up benchmark 'count-global'... Benchmark 'count-global' started. Iter 0 ( 60.659us): hits 53.910M/s ( 13.477M/prod), drops 0.000M/s Iter 1 (-17.658us): hits 53.722M/s ( 13.431M/prod), drops 0.000M/s Iter 2 ( 5.865us): hits 53.495M/s ( 13.374M/prod), drops 0.000M/s Iter 3 ( 0.104us): hits 53.606M/s ( 13.402M/prod), drops 0.000M/s Summary: hits 53.608 ± 0.113M/s ( 13.402M/prod), drops 0.000 ± 0.000M/s $ ./bench -a -w1 -d2 -p4 count-local Setting up benchmark 'count-local'... Benchmark 'count-local' started. Iter 0 ( 23.388us): hits 640.450M/s (160.113M/prod), drops 0.000M/s Iter 1 ( 2.291us): hits 605.661M/s (151.415M/prod), drops 0.000M/s Iter 2 ( -6.415us): hits 607.092M/s (151.773M/prod), drops 0.000M/s Iter 3 ( -1.361us): hits 601.796M/s (150.449M/prod), drops 0.000M/s Summary: hits 604.849 ± 2.739M/s (151.212M/prod), drops 0.000 ± 0.000M/s Benchmark runner supports setting thread affinity for producer and consumer threads. You can use -a flag for default CPU selection scheme, where first consumer gets CPU #0, next one gets CPU #1, and so on. Then producer threads pick up next CPU and increment one-by-one as well. But user can also specify a set of CPUs independently for producers and consumers with --prod-affinity 1,2-10,15 and --cons-affinity <set-of-cpus>. The latter allows to force producers and consumers to share same set of CPUs, if necessary. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-13selftests/bpf: Extract parse_num_list into generic testing_helpers.cAndrii Nakryiko5-64/+78
Add testing_helpers.c, which will contain generic helpers for test runners and tests needing some common generic functionality, like parsing a set of numbers. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-13selftests/bpf: Install generated test progsYauheni Kaliuta1-0/+1
Before commit 74b5a5968fe8 ("selftests/bpf: Replace test_progs and test_maps w/ general rule") selftests/bpf used generic install target from selftests/lib.mk to install generated bpf test progs by mentioning them in TEST_GEN_FILES variable. Take that functionality back. Fixes: 74b5a5968fe8 ("selftests/bpf: Replace test_progs and test_maps w/ general rule") Signed-off-by: Yauheni Kaliuta <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-11bpf, libbpf: Replace zero-length array with flexible-arrayGustavo A. R. Silva1-1/+1
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member conversions) will also help to get completely rid of those sorts of issues. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Yonghong Song <[email protected]> Link: https://lore.kernel.org/bpf/20200507185057.GA13981@embeddedor
2020-05-09tools/bpf: selftests: Add bpf_iter selftestsYonghong Song6-0/+509
The added test includes the following subtests: - test verifier change for btf_id_or_null - test load/create_iter/read for ipv6_route/netlink/bpf_map/task/task_file - test anon bpf iterator - test anon bpf iterator reading one char at a time - test file bpf iterator - test overflow (single bpf program output not overflow) - test overflow (single bpf program output overflows) - test bpf prog returning 1 The ipv6_route tests the following verifier change - access fields in the variable length array of the structure. The netlink load tests the following verifier change - put a btf_id ptr value in a stack and accessible to tracing/iter programs. The anon bpf iterator also tests link auto attach through skeleton. $ test_progs -n 2 #2/1 btf_id_or_null:OK #2/2 ipv6_route:OK #2/3 netlink:OK #2/4 bpf_map:OK #2/5 task:OK #2/6 task_file:OK #2/7 anon:OK #2/8 anon-read-one-char:OK #2/9 file:OK #2/10 overflow:OK #2/11 overflow-e2big:OK #2/12 prog-ret-1:OK #2 bpf_iter:OK Summary: 1/12 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Yonghong Song <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-09tools/bpf: selftests: Add iter progs for bpf_map/task/task_fileYonghong Song3-0/+79
The implementation is arbitrary, just to show how the bpf programs can be written for bpf_map/task/task_file. They can be costomized for specific needs. For example, for bpf_map, the iterator prints out: $ cat /sys/fs/bpf/my_bpf_map id refcnt usercnt locked_vm 3 2 0 20 6 2 0 20 9 2 0 20 12 2 0 20 13 2 0 20 16 2 0 20 19 2 0 20 %%% END %%% For task, the iterator prints out: $ cat /sys/fs/bpf/my_task tgid gid 1 1 2 2 .... 1944 1944 1948 1948 1949 1949 1953 1953 === END === For task/file, the iterator prints out: $ cat /sys/fs/bpf/my_task_file tgid gid fd file 1 1 0 ffffffff95c97600 1 1 1 ffffffff95c97600 1 1 2 ffffffff95c97600 .... 1895 1895 255 ffffffff95c8fe00 1932 1932 0 ffffffff95c8fe00 1932 1932 1 ffffffff95c8fe00 1932 1932 2 ffffffff95c8fe00 1932 1932 3 ffffffff95c185c0 This is able to print out all open files (fd and file->f_op), so user can compare f_op against a particular kernel file operations to find what it is. For example, from /proc/kallsyms, we can find ffffffff95c185c0 r eventfd_fops so we will know tgid 1932 fd 3 is an eventfd file descriptor. Signed-off-by: Yonghong Song <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-09tools/bpf: selftests: Add iterator programs for ipv6_route and netlinkYonghong Song2-0/+128
Two bpf programs are added in this patch for netlink and ipv6_route target. On my VM, I am able to achieve identical results compared to /proc/net/netlink and /proc/net/ipv6_route. $ cat /proc/net/netlink sk Eth Pid Groups Rmem Wmem Dump Locks Drops Inode 000000002c42d58b 0 0 00000000 0 0 0 2 0 7 00000000a4e8b5e1 0 1 00000551 0 0 0 2 0 18719 00000000e1b1c195 4 0 00000000 0 0 0 2 0 16422 000000007e6b29f9 6 0 00000000 0 0 0 2 0 16424 .... 00000000159a170d 15 1862 00000002 0 0 0 2 0 1886 000000009aca4bc9 15 3918224839 00000002 0 0 0 2 0 19076 00000000d0ab31d2 15 1 00000002 0 0 0 2 0 18683 000000008398fb08 16 0 00000000 0 0 0 2 0 27 $ cat /sys/fs/bpf/my_netlink sk Eth Pid Groups Rmem Wmem Dump Locks Drops Inode 000000002c42d58b 0 0 00000000 0 0 0 2 0 7 00000000a4e8b5e1 0 1 00000551 0 0 0 2 0 18719 00000000e1b1c195 4 0 00000000 0 0 0 2 0 16422 000000007e6b29f9 6 0 00000000 0 0 0 2 0 16424 .... 00000000159a170d 15 1862 00000002 0 0 0 2 0 1886 000000009aca4bc9 15 3918224839 00000002 0 0 0 2 0 19076 00000000d0ab31d2 15 1 00000002 0 0 0 2 0 18683 000000008398fb08 16 0 00000000 0 0 0 2 0 27 $ cat /proc/net/ipv6_route fe800000000000000000000000000000 40 00000000000000000000000000000000 00 00000000000000000000000000000000 00000100 00000001 00000000 00000001 eth0 00000000000000000000000000000000 00 00000000000000000000000000000000 00 00000000000000000000000000000000 ffffffff 00000001 00000000 00200200 lo 00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000003 00000000 80200001 lo fe80000000000000c04b03fffe7827ce 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000002 00000000 80200001 eth0 ff000000000000000000000000000000 08 00000000000000000000000000000000 00 00000000000000000000000000000000 00000100 00000003 00000000 00000001 eth0 00000000000000000000000000000000 00 00000000000000000000000000000000 00 00000000000000000000000000000000 ffffffff 00000001 00000000 00200200 lo $ cat /sys/fs/bpf/my_ipv6_route fe800000000000000000000000000000 40 00000000000000000000000000000000 00 00000000000000000000000000000000 00000100 00000001 00000000 00000001 eth0 00000000000000000000000000000000 00 00000000000000000000000000000000 00 00000000000000000000000000000000 ffffffff 00000001 00000000 00200200 lo 00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000003 00000000 80200001 lo fe80000000000000c04b03fffe7827ce 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000002 00000000 80200001 eth0 ff000000000000000000000000000000 08 00000000000000000000000000000000 00 00000000000000000000000000000000 00000100 00000003 00000000 00000001 eth0 00000000000000000000000000000000 00 00000000000000000000000000000000 00 00000000000000000000000000000000 ffffffff 00000001 00000000 00200200 lo Signed-off-by: Yonghong Song <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-09bpf: Allow any port in bpf_bind helperStanislav Fomichev3-0/+171
We want to have a tighter control on what ports we bind to in the BPF_CGROUP_INET{4,6}_CONNECT hooks even if it means connect() becomes slightly more expensive. The expensive part comes from the fact that we now need to call inet_csk_get_port() that verifies that the port is not used and allocates an entry in the hash table for it. Since we can't rely on "snum || !bind_address_no_port" to prevent us from calling POST_BIND hook anymore, let's add another bind flag to indicate that the call site is BPF program. v5: * fix wrong AF_INET (should be AF_INET6) in the bpf program for v6 v3: * More bpf_bind documentation refinements (Martin KaFai Lau) * Add UDP tests as well (Martin KaFai Lau) * Don't start the thread, just do socket+bind+listen (Martin KaFai Lau) v2: * Update documentation (Andrey Ignatov) * Pass BIND_FORCE_ADDRESS_NO_PORT conditionally (Andrey Ignatov) Signed-off-by: Stanislav Fomichev <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Andrey Ignatov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-09selftests/bpf: Move existing common networking parts into network_helpersStanislav Fomichev22-53/+90
1. Move pkt_v4 and pkt_v6 into network_helpers and adjust the users. 2. Copy-paste spin_lock_thread into two tests that use it. Signed-off-by: Stanislav Fomichev <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Acked-by: Andrey Ignatov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-09selftests/bpf: Generalize helpers to control background listenerStanislav Fomichev4-113/+108
Move the following routines that let us start a background listener thread and connect to a server by fd to the test_prog: * start_server - socket+bind+listen * connect_to_fd - connect to the server identified by fd These will be used in the next commit. Also, extend these helpers to support AF_INET6 and accept the family as an argument. v5: * drop pthread.h (Martin KaFai Lau) * add SO_SNDTIMEO (Martin KaFai Lau) v4: * export extra helper to start server without a thread (Martin KaFai Lau) * tcp_rtt is no longer starting background thread (Martin KaFai Lau) v2: * put helpers into network_helpers.c (Andrii Nakryiko) Signed-off-by: Stanislav Fomichev <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Andrey Ignatov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-01selftests/bpf: Use reno instead of dctcpStanislav Fomichev2-4/+3
Andrey pointed out that we can use reno instead of dctcp for CC tests and drop CONFIG_TCP_CONG_DCTCP=y requirement. Fixes: beecf11bc218 ("bpf: Bpf_{g,s}etsockopt for struct bpf_sock_addr") Suggested-by: Andrey Ignatov <[email protected]> Signed-off-by: Stanislav Fomichev <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-01bpf: Bpf_{g,s}etsockopt for struct bpf_sock_addrStanislav Fomichev2-0/+47
Currently, bpf_getsockopt and bpf_setsockopt helpers operate on the 'struct bpf_sock_ops' context in BPF_PROG_TYPE_SOCK_OPS program. Let's generalize them and make them available for 'struct bpf_sock_addr'. That way, in the future, we can allow those helpers in more places. As an example, let's expose those 'struct bpf_sock_addr' based helpers to BPF_CGROUP_INET{4,6}_CONNECT hooks. That way we can override CC before the connection is made. v3: * Expose custom helpers for bpf_sock_addr context instead of doing generic bpf_sock argument (as suggested by Daniel). Even with try_socket_lock that doesn't sleep we have a problem where context sk is already locked and socket lock is non-nestable. v2: * s/BPF_PROG_TYPE_CGROUP_SOCKOPT/BPF_PROG_TYPE_SOCK_OPS/ Signed-off-by: Stanislav Fomichev <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Martin KaFai Lau <[email protected]> Acked-by: John Fastabend <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-05-01bpf: Add selftest for BPF_ENABLE_STATSSong Liu2-0/+63
Add test for BPF_ENABLE_STATS, which should enable run_time_ns stats. ~/selftests/bpf# ./test_progs -t enable_stats -v test_enable_stats:PASS:skel_open_and_load 0 nsec test_enable_stats:PASS:get_stats_fd 0 nsec test_enable_stats:PASS:attach_raw_tp 0 nsec test_enable_stats:PASS:get_prog_info 0 nsec test_enable_stats:PASS:check_stats_enabled 0 nsec test_enable_stats:PASS:check_run_cnt_valid 0 nsec Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Song Liu <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-30selftests/bpf: Test allowed maps for bpf_sk_select_reuseportJakub Sitnicki2-1/+56
Check that verifier allows passing a map of type: BPF_MAP_TYPE_REUSEPORT_SOCKARRARY, or BPF_MAP_TYPE_SOCKMAP, or BPF_MAP_TYPE_SOCKHASH ... to bpf_sk_select_reuseport helper. Suggested-by: John Fastabend <[email protected]> Signed-off-by: Jakub Sitnicki <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-29selftests/bpf: Use SOCKMAP for server sockets in bpf_sk_assign testJakub Sitnicki3-52/+53
Update bpf_sk_assign test to fetch the server socket from SOCKMAP, now that map lookup from BPF in SOCKMAP is enabled. This way the test TC BPF program doesn't need to know what address server socket is bound to. Signed-off-by: Jakub Sitnicki <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: John Fastabend <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-29selftests/bpf: Test that lookup on SOCKMAP/SOCKHASH is allowedJakub Sitnicki2-30/+70
Now that bpf_map_lookup_elem() is white-listed for SOCKMAP/SOCKHASH, replace the tests which check that verifier prevents lookup on these map types with ones that ensure that lookup operation is permitted, but only with a release of acquired socket reference. Signed-off-by: Jakub Sitnicki <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: John Fastabend <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28selftests/bpf: Add runqslower binary to .gitignoreAndrii Nakryiko1-1/+1
With recent changes, runqslower is being copied into selftests/bpf root directory. So add it into .gitignore. Fixes: b26d1e2b6028 ("selftests/bpf: Copy runqslower to OUTPUT directory") Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Cc: Veronika Kabatova <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28selftests/bpf: Fix bpf_link leak in ns_current_pid_tgid selftestAndrii Nakryiko1-4/+1
If condition is inverted, but it's also just not necessary. Fixes: 1c1052e0140a ("tools/testing/selftests/bpf: Add self-tests for new helper bpf_get_ns_current_pid_tgid.") Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Cc: Carlos Neira <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28selftests/bpf: Disable ASAN instrumentation for mmap()'ed memory readAndrii Nakryiko1-0/+5
AddressSanitizer assumes that all memory dereferences are done against memory allocated by sanitizer's malloc()/free() code and not touched by anyone else. Seems like this doesn't hold for perf buffer memory. Disable instrumentation on perf buffer callback function. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28selftests/bpf: Fix invalid memory reads in core_relo selftestAndrii Nakryiko1-1/+1
Another one found by AddressSanitizer. input_len is bigger than actually initialized data size. Fixes: c7566a69695c ("selftests/bpf: Add field existence CO-RE relocs tests") Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28selftests/bpf: Fix memory leak in extract_build_id()Andrii Nakryiko1-0/+1
getline() allocates string, which has to be freed. Fixes: 81f77fd0deeb ("bpf: add selftest for stackmap with BPF_F_STACK_BUILD_ID") Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Cc: Song Liu <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28selftests/bpf: Fix memory leak in test selectorAndrii Nakryiko1-4/+16
Free test selector substrings, which were strdup()'ed. Fixes: b65053cd94f4 ("selftests/bpf: Add whitelist/blacklist of test names to test_progs") Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28selftests/bpf: Convert test_hashmap into test_progs testAndrii Nakryiko3-144/+140
Fold stand-alone test_hashmap test into test_progs. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28selftests/bpf: Add SAN_CFLAGS param to selftests build to allow sanitizersAndrii Nakryiko1-3/+4
Add ability to specify extra compiler flags with SAN_CFLAGS for compilation of all user-space C files. This allows to build all of selftest programs with, e.g., custom sanitizer flags, without requiring support for such sanitizers from anyone compiling selftest/bpf. As an example, to compile everything with AddressSanitizer, one would do: $ make clean && make SAN_CFLAGS="-fsanitize=address" For AddressSanitizer to work, one needs appropriate libasan shared library installed in the system, with version of libasan matching what GCC links against. E.g., GCC8 needs libasan5, while GCC7 uses libasan4. For CentOS 7, to build everything successfully one would need to: $ sudo yum install devtoolset-8-gcc devtoolset-libasan-devel $ scl enable devtoolset-8 bash # set up environment For Arch Linux to run selftests, one would need to install gcc-libs package to get libasan.so.5: $ sudo pacman -S gcc-libs N.B. EXTRA_CFLAGS name wasn't used, because it's also used by libbpf's Makefile and this causes few issues: 1. default "-g -Wall" flags are overriden; 2. compiling shared library with AddressSanitizer generates a bunch of symbols like: "_GLOBAL__sub_D_00099_0_btf_dump.c", "_GLOBAL__sub_D_00099_0_bpf.c", etc, which screws up versioned symbols check. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Cc: Julia Kartseva <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28selftests/bpf: Ensure test flavors use correct skeletonsAndrii Nakryiko1-1/+1
Ensure that test runner flavors include their own skeletons from <flavor>/ directory. Previously, skeletons generated for no-flavor test_progs were used. Apart from fixing correctness, this also makes it possible to compile only flavors individually: $ make clean && make test_progs-no_alu32 ... now succeeds ... Fixes: 74b5a5968fe8 ("selftests/bpf: Replace test_progs and test_maps w/ general rule") Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28libbpf: Add BTF-defined map-in-map supportAndrii Nakryiko2-0/+125
As discussed at LPC 2019 ([0]), this patch brings (a quite belated) support for declarative BTF-defined map-in-map support in libbpf. It allows to define ARRAY_OF_MAPS and HASH_OF_MAPS BPF maps without any user-space initialization code involved. Additionally, it allows to initialize outer map's slots with references to respective inner maps at load time, also completely declaratively. Despite a weak type system of C, the way BTF-defined map-in-map definition works, it's actually quite hard to accidentally initialize outer map with incompatible inner maps. This being C, of course, it's still possible, but even that would be caught at load time and error returned with helpful debug log pointing exactly to the slot that failed to be initialized. As an example, here's a rather advanced HASH_OF_MAPS declaration and initialization example, filling slots #0 and #4 with two inner maps: #include <bpf/bpf_helpers.h> struct inner_map { __uint(type, BPF_MAP_TYPE_ARRAY); __uint(max_entries, 1); __type(key, int); __type(value, int); } inner_map1 SEC(".maps"), inner_map2 SEC(".maps"); struct outer_hash { __uint(type, BPF_MAP_TYPE_HASH_OF_MAPS); __uint(max_entries, 5); __uint(key_size, sizeof(int)); __array(values, struct inner_map); } outer_hash SEC(".maps") = { .values = { [0] = &inner_map2, [4] = &inner_map1, }, }; Here's the relevant part of libbpf debug log showing pretty clearly of what's going on with map-in-map initialization: libbpf: .maps relo #0: for 6 value 0 rel.r_offset 96 name 260 ('inner_map1') libbpf: .maps relo #0: map 'outer_arr' slot [0] points to map 'inner_map1' libbpf: .maps relo #1: for 7 value 32 rel.r_offset 112 name 249 ('inner_map2') libbpf: .maps relo #1: map 'outer_arr' slot [2] points to map 'inner_map2' libbpf: .maps relo #2: for 7 value 32 rel.r_offset 144 name 249 ('inner_map2') libbpf: .maps relo #2: map 'outer_hash' slot [0] points to map 'inner_map2' libbpf: .maps relo #3: for 6 value 0 rel.r_offset 176 name 260 ('inner_map1') libbpf: .maps relo #3: map 'outer_hash' slot [4] points to map 'inner_map1' libbpf: map 'inner_map1': created successfully, fd=4 libbpf: map 'inner_map2': created successfully, fd=5 libbpf: map 'outer_hash': created successfully, fd=7 libbpf: map 'outer_hash': slot [0] set to map 'inner_map2' fd=5 libbpf: map 'outer_hash': slot [4] set to map 'inner_map1' fd=4 Notice from the log above that fd=6 (not logged explicitly) is used for inner "prototype" map, necessary for creation of outer map. It is destroyed immediately after outer map is created. See also included selftest with some extra comments explaining extra details of usage. Additionally, similar initialization syntax and libbpf functionality can be used to do initialization of BPF_PROG_ARRAY with references to BPF sub-programs. This can be done in follow up patches, if there will be a demand for this. [0] https://linuxplumbersconf.org/event/4/contributions/448/ Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Toke Høiland-Jørgensen <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28selftests/bpf: Test bpf_link's get_next_id, get_fd_by_id, and get_obj_infoAndrii Nakryiko2-20/+104
Extend bpf_obj_id selftest to verify bpf_link's observability APIs. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-28selftests/bpf: fix test_sysctl_prog with alu32Alexei Starovoitov1-1/+1
Similar to commit b7a0d65d80a0 ("bpf, testing: Workaround a verifier failure for test_progs") fix test_sysctl_prog.c as well. Signed-off-by: Alexei Starovoitov <[email protected]>
2020-04-28selftests/bpf: Copy runqslower to OUTPUT directoryVeronika Kabatova1-1/+2
$(OUTPUT)/runqslower makefile target doesn't actually create runqslower binary in the $(OUTPUT) directory. As lib.mk expects all TEST_GEN_PROGS_EXTENDED (which runqslower is a part of) to be present in the OUTPUT directory, this results in an error when running e.g. `make install`: rsync: link_stat "tools/testing/selftests/bpf/runqslower" failed: No such file or directory (2) Copy the binary into the OUTPUT directory after building it to fix the error. Fixes: 3a0d3092a4ed ("selftests/bpf: Build runqslower from selftests") Signed-off-by: Veronika Kabatova <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-26selftests/bpf: Add cls_redirect classifierLorenz Bauer4-0/+1575
cls_redirect is a TC clsact based replacement for the glb-redirect iptables module available at [1]. It enables what GitHub calls "second chance" flows [2], similarly proposed by the Beamer paper [3]. In contrast to glb-redirect, it also supports migrating UDP flows as long as connected sockets are used. cls_redirect is in production at Cloudflare, as part of our own L4 load balancer. We have modified the encapsulation format slightly from glb-redirect: glbgue_chained_routing.private_data_type has been repurposed to form a version field and several flags. Both have been arranged in a way that a private_data_type value of zero matches the current glb-redirect behaviour. This means that cls_redirect will understand packets in glb-redirect format, but not vice versa. The test suite only covers basic features. For example, cls_redirect will correctly forward path MTU discovery packets, but this is not exercised. It is also possible to switch the encapsulation format to GRE on the last hop, which is also not tested. There are two major distinctions from glb-redirect: first, cls_redirect relies on receiving encapsulated packets directly from a router. This is because we don't have access to the neighbour tables from BPF, yet. See forward_to_next_hop for details. Second, cls_redirect performs decapsulation instead of using separate ipip and sit tunnel devices. This avoids issues with the sit tunnel [4] and makes deploying the classifier easier: decapsulated packets appear on the same interface, so existing firewall rules continue to work as expected. The code base started it's life on v4.19, so there are most likely still hold overs from old workarounds. In no particular order: - The function buf_off is required to defeat a clang optimization that leads to the verifier rejecting the program due to pointer arithmetic in the wrong order. - The function pkt_parse_ipv6 is force inlined, because it would otherwise be rejected due to returning a pointer to stack memory. - The functions fill_tuple and classify_tcp contain kludges, because we've run out of function arguments. - The logic in general is rather nested, due to verifier restrictions. I think this is either because the verifier loses track of constants on the stack, or because it can't track enum like variables. 1: https://github.com/github/glb-director/tree/master/src/glb-redirect 2: https://github.com/github/glb-director/blob/master/docs/development/second-chance-design.md 3: https://www.usenix.org/conference/nsdi18/presentation/olteanu 4: https://github.com/github/glb-director/issues/64 Signed-off-by: Lorenz Bauer <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-26bpf: Make verifier log more relevant by defaultAndrii Nakryiko1-1/+6
To make BPF verifier verbose log more releavant and easier to use to debug verification failures, "pop" parts of log that were successfully verified. This has effect of leaving only verifier logs that correspond to code branches that lead to verification failure, which in practice should result in much shorter and more relevant verifier log dumps. This behavior is made the default behavior and can be overriden to do exhaustive logging by specifying BPF_LOG_LEVEL2 log level. Using BPF_LOG_LEVEL2 to disable this behavior is not ideal, because in some cases it's good to have BPF_LOG_LEVEL2 per-instruction register dump verbosity, but still have only relevant verifier branches logged. But for this patch, I didn't want to add any new flags. It might be worth-while to just rethink how BPF verifier logging is performed and requested and streamline it a bit. But this trimming of successfully verified branches seems to be useful and a good default behavior. To test this, I modified runqslower slightly to introduce read of uninitialized stack variable. Log (**truncated in the middle** to save many lines out of this commit message) BEFORE this change: ; int handle__sched_switch(u64 *ctx) 0: (bf) r6 = r1 ; struct task_struct *prev = (struct task_struct *)ctx[1]; 1: (79) r1 = *(u64 *)(r6 +8) func 'sched_switch' arg1 has btf_id 151 type STRUCT 'task_struct' 2: (b7) r2 = 0 ; struct event event = {}; 3: (7b) *(u64 *)(r10 -24) = r2 last_idx 3 first_idx 0 regs=4 stack=0 before 2: (b7) r2 = 0 4: (7b) *(u64 *)(r10 -32) = r2 5: (7b) *(u64 *)(r10 -40) = r2 6: (7b) *(u64 *)(r10 -48) = r2 ; if (prev->state == TASK_RUNNING) [ ... instruction dump from insn #7 through #50 are cut out ... ] 51: (b7) r2 = 16 52: (85) call bpf_get_current_comm#16 last_idx 52 first_idx 42 regs=4 stack=0 before 51: (b7) r2 = 16 ; bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, 53: (bf) r1 = r6 54: (18) r2 = 0xffff8881f3868800 56: (18) r3 = 0xffffffff 58: (bf) r4 = r7 59: (b7) r5 = 32 60: (85) call bpf_perf_event_output#25 last_idx 60 first_idx 53 regs=20 stack=0 before 59: (b7) r5 = 32 61: (bf) r2 = r10 ; event.pid = pid; 62: (07) r2 += -16 ; bpf_map_delete_elem(&start, &pid); 63: (18) r1 = 0xffff8881f3868000 65: (85) call bpf_map_delete_elem#3 ; } 66: (b7) r0 = 0 67: (95) exit from 44 to 66: safe from 34 to 66: safe from 11 to 28: R1_w=inv0 R2_w=inv0 R6_w=ctx(id=0,off=0,imm=0) R10=fp0 fp-8=mmmm???? fp-24_w=00000000 fp-32_w=00000000 fp-40_w=00000000 fp-48_w=00000000 ; bpf_map_update_elem(&start, &pid, &ts, 0); 28: (bf) r2 = r10 ; 29: (07) r2 += -16 ; tsp = bpf_map_lookup_elem(&start, &pid); 30: (18) r1 = 0xffff8881f3868000 32: (85) call bpf_map_lookup_elem#1 invalid indirect read from stack off -16+0 size 4 processed 65 insns (limit 1000000) max_states_per_insn 1 total_states 5 peak_states 5 mark_read 4 Notice how there is a successful code path from instruction 0 through 67, few successfully verified jumps (44->66, 34->66), and only after that 11->28 jump plus error on instruction #32. AFTER this change (full verifier log, **no truncation**): ; int handle__sched_switch(u64 *ctx) 0: (bf) r6 = r1 ; struct task_struct *prev = (struct task_struct *)ctx[1]; 1: (79) r1 = *(u64 *)(r6 +8) func 'sched_switch' arg1 has btf_id 151 type STRUCT 'task_struct' 2: (b7) r2 = 0 ; struct event event = {}; 3: (7b) *(u64 *)(r10 -24) = r2 last_idx 3 first_idx 0 regs=4 stack=0 before 2: (b7) r2 = 0 4: (7b) *(u64 *)(r10 -32) = r2 5: (7b) *(u64 *)(r10 -40) = r2 6: (7b) *(u64 *)(r10 -48) = r2 ; if (prev->state == TASK_RUNNING) 7: (79) r2 = *(u64 *)(r1 +16) ; if (prev->state == TASK_RUNNING) 8: (55) if r2 != 0x0 goto pc+19 R1_w=ptr_task_struct(id=0,off=0,imm=0) R2_w=inv0 R6_w=ctx(id=0,off=0,imm=0) R10=fp0 fp-24_w=00000000 fp-32_w=00000000 fp-40_w=00000000 fp-48_w=00000000 ; trace_enqueue(prev->tgid, prev->pid); 9: (61) r1 = *(u32 *)(r1 +1184) 10: (63) *(u32 *)(r10 -4) = r1 ; if (!pid || (targ_pid && targ_pid != pid)) 11: (15) if r1 == 0x0 goto pc+16 from 11 to 28: R1_w=inv0 R2_w=inv0 R6_w=ctx(id=0,off=0,imm=0) R10=fp0 fp-8=mmmm???? fp-24_w=00000000 fp-32_w=00000000 fp-40_w=00000000 fp-48_w=00000000 ; bpf_map_update_elem(&start, &pid, &ts, 0); 28: (bf) r2 = r10 ; 29: (07) r2 += -16 ; tsp = bpf_map_lookup_elem(&start, &pid); 30: (18) r1 = 0xffff8881db3ce800 32: (85) call bpf_map_lookup_elem#1 invalid indirect read from stack off -16+0 size 4 processed 65 insns (limit 1000000) max_states_per_insn 1 total_states 5 peak_states 5 mark_read 4 Notice how in this case, there are 0-11 instructions + jump from 11 to 28 is recorded + 28-32 instructions with error on insn #32. test_verifier test runner was updated to specify BPF_LOG_LEVEL2 for VERBOSE_ACCEPT expected result due to potentially "incomplete" success verbose log at BPF_LOG_LEVEL1. On success, verbose log will only have a summary of number of processed instructions, etc, but no branch tracing log. Having just a last succesful branch tracing seemed weird and confusing. Having small and clean summary log in success case seems quite logical and nice, though. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-26bpf: Enable more helpers for BPF_PROG_TYPE_CGROUP_{DEVICE,SYSCTL,SOCKOPT}Stanislav Fomichev1-0/+24
Currently the following prog types don't fall back to bpf_base_func_proto() (instead they have cgroup_base_func_proto which has a limited set of helpers from bpf_base_func_proto): * BPF_PROG_TYPE_CGROUP_DEVICE * BPF_PROG_TYPE_CGROUP_SYSCTL * BPF_PROG_TYPE_CGROUP_SOCKOPT I don't see any specific reason why we shouldn't use bpf_base_func_proto(), every other type of program (except bpf-lirc and, understandably, tracing) use it, so let's fall back to bpf_base_func_proto for those prog types as well. This basically boils down to adding access to the following helpers: * BPF_FUNC_get_prandom_u32 * BPF_FUNC_get_smp_processor_id * BPF_FUNC_get_numa_node_id * BPF_FUNC_tail_call * BPF_FUNC_ktime_get_ns * BPF_FUNC_spin_lock (CAP_SYS_ADMIN) * BPF_FUNC_spin_unlock (CAP_SYS_ADMIN) * BPF_FUNC_jiffies64 (CAP_SYS_ADMIN) I've also added bpf_perf_event_output() because it's really handy for logging and debugging. Signed-off-by: Stanislav Fomichev <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-24selftests/bpf: Fix a couple of broken test_btf casesStanislav Fomichev4-40/+16
Commit 51c39bb1d5d1 ("bpf: Introduce function-by-function verification") introduced function linkage flag and changed the error message from "vlen != 0" to "Invalid func linkage" and broke some fake BPF programs. Adjust the test accordingly. AFACT, the programs don't really need any arguments and only look at BTF for maps, so let's drop the args altogether. Before: BTF raw test[103] (func (Non zero vlen)): do_test_raw:3703:FAIL expected err_str:vlen != 0 magic: 0xeb9f version: 1 flags: 0x0 hdr_len: 24 type_off: 0 type_len: 72 str_off: 72 str_len: 10 btf_total_size: 106 [1] INT (anon) size=4 bits_offset=0 nr_bits=32 encoding=SIGNED [2] INT (anon) size=4 bits_offset=0 nr_bits=32 encoding=(none) [3] FUNC_PROTO (anon) return=0 args=(1 a, 2 b) [4] FUNC func type_id=3 Invalid func linkage BTF libbpf test[1] (test_btf_haskv.o): libbpf: load bpf program failed: Invalid argument libbpf: -- BEGIN DUMP LOG --- libbpf: Validating test_long_fname_2() func#1... Arg#0 type PTR in test_long_fname_2() is not supported yet. processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 libbpf: -- END LOG -- libbpf: failed to load program 'dummy_tracepoint' libbpf: failed to load object 'test_btf_haskv.o' do_test_file:4201:FAIL bpf_object__load: -4007 BTF libbpf test[2] (test_btf_newkv.o): libbpf: load bpf program failed: Invalid argument libbpf: -- BEGIN DUMP LOG --- libbpf: Validating test_long_fname_2() func#1... Arg#0 type PTR in test_long_fname_2() is not supported yet. processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 libbpf: -- END LOG -- libbpf: failed to load program 'dummy_tracepoint' libbpf: failed to load object 'test_btf_newkv.o' do_test_file:4201:FAIL bpf_object__load: -4007 BTF libbpf test[3] (test_btf_nokv.o): libbpf: load bpf program failed: Invalid argument libbpf: -- BEGIN DUMP LOG --- libbpf: Validating test_long_fname_2() func#1... Arg#0 type PTR in test_long_fname_2() is not supported yet. processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 libbpf: -- END LOG -- libbpf: failed to load program 'dummy_tracepoint' libbpf: failed to load object 'test_btf_nokv.o' do_test_file:4201:FAIL bpf_object__load: -4007 Fixes: 51c39bb1d5d1 ("bpf: Introduce function-by-function verification") Signed-off-by: Stanislav Fomichev <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-24selftests/bpf: Add test for freplace program with expected_attach_typeToke Høiland-Jørgensen3-18/+58
This adds a new selftest that tests the ability to attach an freplace program to a program type that relies on the expected_attach_type of the target program to pass verification. Signed-off-by: Toke Høiland-Jørgensen <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-20bpf, selftests: Add test for BPF_STX BPF_B storing R10Luke Nelson1-0/+40
This patch adds a test to test_verifier that writes the lower 8 bits of R10 (aka FP) using BPF_B to an array map and reads the result back. The expected behavior is that the result should be the same as first copying R10 to R9, and then storing / loading the lower 8 bits of R9. This test catches a bug that was present in the x86-64 JIT that caused an incorrect encoding for BPF_STX BPF_B when the source operand is R10. Signed-off-by: Xi Wang <[email protected]> Signed-off-by: Luke Nelson <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-20bpf: Forbid XADD on spilled pointers for unprivileged usersJann Horn1-0/+1
When check_xadd() verifies an XADD operation on a pointer to a stack slot containing a spilled pointer, check_stack_read() verifies that the read, which is part of XADD, is valid. However, since the placeholder value -1 is passed as `value_regno`, check_stack_read() can only return a binary decision and can't return the type of the value that was read. The intent here is to verify whether the value read from the stack slot may be used as a SCALAR_VALUE; but since check_stack_read() doesn't check the type, and the type information is lost when check_stack_read() returns, this is not enforced, and a malicious user can abuse XADD to leak spilled kernel pointers. Fix it by letting check_stack_read() verify that the value is usable as a SCALAR_VALUE if no type information is passed to the caller. To be able to use __is_pointer_value() in check_stack_read(), move it up. Fix up the expected unprivileged error message for a BPF selftest that, until now, assumed that unprivileged users can use XADD on stack-spilled pointers. This also gives us a test for the behavior introduced in this patch for free. In theory, this could also be fixed by forbidding XADD on stack spills entirely, since XADD is a locked operation (for operations on memory with concurrency) and there can't be any concurrency on the BPF stack; but Alexei has said that he wants to keep XADD on stack slots working to avoid changes to the test suite [1]. The following BPF program demonstrates how to leak a BPF map pointer as an unprivileged user using this bug: // r7 = map_pointer BPF_LD_MAP_FD(BPF_REG_7, small_map), // r8 = launder(map_pointer) BPF_STX_MEM(BPF_DW, BPF_REG_FP, BPF_REG_7, -8), BPF_MOV64_IMM(BPF_REG_1, 0), ((struct bpf_insn) { .code = BPF_STX | BPF_DW | BPF_XADD, .dst_reg = BPF_REG_FP, .src_reg = BPF_REG_1, .off = -8 }), BPF_LDX_MEM(BPF_DW, BPF_REG_8, BPF_REG_FP, -8), // store r8 into map BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_7), BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_FP), BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG2, -4), BPF_ST_MEM(BPF_W, BPF_REG_ARG2, 0, 0), BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem), BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1), BPF_EXIT_INSN(), BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_8, 0), BPF_MOV64_IMM(BPF_REG_0, 0), BPF_EXIT_INSN() [1] https://lore.kernel.org/bpf/[email protected]/ Fixes: 17a5267067f3 ("bpf: verifier (add verifier core)") Signed-off-by: Jann Horn <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-15selftests/bpf: Check for correct program attach/detach in xdp_attach testToke Høiland-Jørgensen1-1/+29
David Ahern noticed that there was a bug in the EXPECTED_FD code so programs did not get detached properly when that parameter was supplied. This case was not included in the xdp_attach tests; so let's add it to be sure that such a bug does not sneak back in down. Fixes: 87854a0b57b3 ("selftests/bpf: Add tests for attaching XDP programs") Reported-by: David Ahern <[email protected]> Signed-off-by: Toke Høiland-Jørgensen <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Song Liu <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-15libbpf: Always specify expected_attach_type on program load if supportedAndrii Nakryiko1-15/+27
For some types of BPF programs that utilize expected_attach_type, libbpf won't set load_attr.expected_attach_type, even if expected_attach_type is known from section definition. This was done to preserve backwards compatibility with old kernels that didn't recognize expected_attach_type attribute yet (which was added in 5e43f899b03a ("bpf: Check attach type at prog load time"). But this is problematic for some BPF programs that utilize newer features that require kernel to know specific expected_attach_type (e.g., extended set of return codes for cgroup_skb/egress programs). This patch makes libbpf specify expected_attach_type by default, but also detect support for this field in kernel and not set it during program load. This allows to have a good metadata for bpf_program (e.g., bpf_program__get_extected_attach_type()), but still work with old kernels (for cases where it can work at all). Additionally, due to expected_attach_type being always set for recognized program types, bpf_program__attach_cgroup doesn't have to do extra checks to determine correct attach type, so remove that additional logic. Also adjust section_names selftest to account for this change. More detailed discussion can be found in [0]. [0] https://lore.kernel.org/bpf/[email protected]/ Fixes: 5cf1e9145630 ("bpf: cgroup inet skb programs can return 0 to 3") Fixes: 5e43f899b03a ("bpf: Check attach type at prog load time") Reported-by: Andrey Ignatov <[email protected]> Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Song Liu <[email protected]> Acked-by: Andrey Ignatov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-14selftests/bpf: Validate frozen map contents stays frozenAndrii Nakryiko1-2/+60
Test that frozen and mmap()'ed BPF map can't be mprotect()'ed as writable or executable memory. Also validate that "downgrading" from writable to read-only doesn't screw up internal writable count accounting for the purposes of map freezing. Signed-off-by: Andrii Nakryiko <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2020-04-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller4-15/+83
Daniel Borkmann says: ==================== pull-request: bpf 2020-04-10 The following pull-request contains BPF updates for your *net* tree. We've added 13 non-merge commits during the last 7 day(s) which contain a total of 13 files changed, 137 insertions(+), 43 deletions(-). The main changes are: 1) JIT code emission fixes for riscv and arm32, from Luke Nelson and Xi Wang. 2) Disable vmlinux BTF info if GCC_PLUGIN_RANDSTRUCT is used, from Slava Bacherikov. 3) Fix oob write in AF_XDP when meta data is used, from Li RongQing. 4) Fix bpf_get_link_xdp_id() handling on single prog when flags are specified, from Andrey Ignatov. 5) Fix sk_assign() BPF helper for request sockets that can have sk_reuseport field uninitialized, from Joe Stringer. 6) Fix mprotect() test case for the BPF LSM, from KP Singh. ==================== Signed-off-by: David S. Miller <[email protected]>
2020-04-08selftests/bpf: Add test for bpf_get_link_xdp_idAndrey Ignatov1-0/+68
Add xdp_info selftest that makes sure that bpf_get_link_xdp_id returns valid prog_id for different input modes: * w/ and w/o flags when no program is attached; * w/ and w/o flags when one program is attached. Signed-off-by: Andrey Ignatov <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Link: https://lore.kernel.org/bpf/2a9a6d1ce33b91ccc1aa3de6dba2d309f2062811.1586236080.git.rdna@fb.com
2020-04-03Merge tag 'spdx-5.7-rc1' of ↵Linus Torvalds4-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx Pull SPDX updates from Greg KH: "Here are three SPDX patches for 5.7-rc1. One fixes up the SPDX tag for a single driver, while the other two go through the tree and add SPDX tags for all of the .gitignore files as needed. Nothing too complex, but you will get a merge conflict with your current tree, that should be trivial to handle (one file modified by two things, one file deleted.) All three of these have been in linux-next for a while, with no reported issues other than the merge conflict" * tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx: ASoC: MT6660: make spdxcheck.py happy .gitignore: add SPDX License Identifier .gitignore: remove too obvious comments
2020-04-02bpf, lsm: Fix the file_mprotect LSM test.KP Singh2-13/+13
The test was previously using an mprotect on the heap memory allocated using malloc and was expecting the allocation to be always using sbrk(2). This is, however, not always true and in certain conditions malloc may end up using anonymous mmaps for heap alloctions. This means that the following condition that is used in the "lsm/file_mprotect" program is not sufficent to detect all mprotect calls done on heap memory: is_heap = (vma->vm_start >= vma->vm_mm->start_brk && vma->vm_end <= vma->vm_mm->brk); The test is updated to use an mprotect on memory allocated on the stack. While this would result in the splitting of the vma, this happens only after the security_file_mprotect hook. So, the condition used in the BPF program holds true. Fixes: 03e54f100d57 ("bpf: lsm: Add selftests for BPF_PROG_TYPE_LSM") Reported-by: Alexei Starovoitov <[email protected]> Signed-off-by: KP Singh <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]