v1: https://lore.kernel.org/bpf/20230208205642.270567-1-iii@xxxxxxxxxxxxx/ v1 -> v2: - Apply runqslower's EXTRA_CFLAGS and EXTRA_LDFLAGS unconditionally. - Use u64 for uretprobe_byname2_rc. - Use BPF_UPROBE() instead of PT_REGS_xxx(). - Use void * instead of char * for pointer arithmetic. - Rename libbpf_mark_defined() to __libbpf_mark_mem_written(), add convenience wrappers. - Add a comment about defined(__has_feature) && __has_feature(memory_sanitizer). - Extract is_percpu_bpf_map_type(). - Introduce bpf_get_{map,prog,link,btf}_info_by_fd() and convert all code to use them. If it's too early for that, in particular for samples and perf, the respective patches can be dropped. - Unpoison infos returned by these functions, paying attention to potentially missing fields. Use macros to reduce boilerplate. - Move capget() unpoisoning to LLVM [5]. - With that, only a few cases remain where data needs to be unpoisoned in selftests. Hi, This series adds support for building selftests with Memory Sanitizer [1] - a compiler instrumentation for detecting usages of undefined memory. The primary motivation is to make sure that such usages do not occur during testing, since the ones that have not been caught yet are likely to affect the CI results on s390x. The secondary motivation is to be able to use libbpf in applications instrumented with MSan (it requires all code running in a process to be instrumented). MSan has found one real issue (fixed by patch 7), and of course a number of false positives. This rest of this series deals with preparing the build infrastructure and adding MSan annotations to libbpf and selftests. The setup I'm using is as follows: - Instrumented zlib-ng and patched elfutils [2]. - Patched LLVM [3, 4, 5]. - Clang-built kernel. - Building tests with MSan: make \ -C tools/testing/selftests/bpf \ CC="ccache clang-17" \ LD=ld \ HOSTCC="ccache clang-17" \ HOSTLD=ld \ LLVM=1 \ LLVM_SUFFIX=-17 \ OBJCOPY=objcopy \ CLANG="ccache clang-17" \ LLVM_STRIP=llvm-strip-17 \ LLC=llc-17 \ BPF_GCC= \ SAN_CFLAGS="-fsanitize=memory \ -fsanitize-memory-track-origins \ -I$PWD/../zlib-ng/dist/include \ -I$PWD/../elfutils/dist/include" \ SAN_LDFLAGS="-fsanitize=memory \ -fsanitize-memory-track-origins \ -L$PWD/../zlib-ng/dist/lib \ -L$PWD/../elfutils/dist/lib" \ CROSS_COMPILE=s390x-linux-gnu- It's a lot of options, but most of them are trivial: setting up LLVM toolchain, taking in account s390x quirks, setting up MSan and disabling bpf-gcc. The CROSS_COMPILE one is a hack: instrumenting bpftool turned out to be too complicated from the build system perspective, so having CROSS_COMPILE forces compiling the host libbpf uninstrumented and guest libbpf instrumented. - Running tests with MSan on s390x: LD_LIBRARY_PATH=<instrumented libs> ./test_progs ... Summary: 282/1624 PASSED, 23 SKIPPED, 4 FAILED The 4 failures happen without MSan too, they are already known and denylisted. Best regards, Ilya [1] https://clang.llvm.org/docs/MemorySanitizer.html [2] https://sourceware.org/pipermail/elfutils-devel/2023q1/005831.html [3] https://reviews.llvm.org/D143296 [4] https://reviews.llvm.org/D143330 [5] https://reviews.llvm.org/D143660 Ilya Leoshkevich (16): selftests/bpf: Quote host tools tools: runqslower: Add EXTRA_CFLAGS and EXTRA_LDFLAGS support selftests/bpf: Split SAN_CFLAGS and SAN_LDFLAGS selftests/bpf: Forward SAN_CFLAGS and SAN_LDFLAGS to runqslower and libbpf selftests/bpf: Attach to fopen()/fclose() in uprobe_autoattach selftests/bpf: Attach to fopen()/fclose() in attach_probe libbpf: Fix alen calculation in libbpf_nla_dump_errormsg() libbpf: Introduce bpf_{btf,link,map,prog}_get_info_by_fd() libbpf: Use bpf_{btf,link,map,prog}_get_info_by_fd() bpftool: Use bpf_{btf,link,map,prog}_get_info_by_fd() perf: Use bpf_{btf,link,map,prog}_get_info_by_fd() samples/bpf: Use bpf_{btf,link,map,prog}_get_info_by_fd() selftests/bpf: Use bpf_{btf,link,map,prog}_get_info_by_fd() libbpf: Factor out is_percpu_bpf_map_type() libbpf: Add MSan annotations selftests/bpf: Add MSan annotations samples/bpf/test_map_in_map_user.c | 2 +- samples/bpf/xdp1_user.c | 2 +- samples/bpf/xdp_adjust_tail_user.c | 2 +- samples/bpf/xdp_fwd_user.c | 4 +- samples/bpf/xdp_redirect_cpu_user.c | 4 +- samples/bpf/xdp_rxq_info_user.c | 2 +- samples/bpf/xdp_sample_pkts_user.c | 2 +- samples/bpf/xdp_tx_iptunnel_user.c | 2 +- tools/bpf/bpftool/btf.c | 13 +- tools/bpf/bpftool/btf_dumper.c | 4 +- tools/bpf/bpftool/cgroup.c | 4 +- tools/bpf/bpftool/common.c | 13 +- tools/bpf/bpftool/link.c | 4 +- tools/bpf/bpftool/main.h | 3 +- tools/bpf/bpftool/map.c | 8 +- tools/bpf/bpftool/prog.c | 24 +-- tools/bpf/bpftool/struct_ops.c | 6 +- tools/bpf/runqslower/Makefile | 2 + tools/lib/bpf/bpf.c | 179 +++++++++++++++++- tools/lib/bpf/bpf.h | 13 ++ tools/lib/bpf/btf.c | 9 +- tools/lib/bpf/libbpf.c | 26 +-- tools/lib/bpf/libbpf.map | 5 + tools/lib/bpf/libbpf_internal.h | 46 +++++ tools/lib/bpf/netlink.c | 2 +- tools/lib/bpf/nlattr.c | 2 +- tools/lib/bpf/ringbuf.c | 4 +- tools/perf/util/bpf-utils.c | 4 +- tools/perf/util/bpf_counter.c | 2 +- tools/perf/util/bpf_counter.h | 6 +- tools/testing/selftests/bpf/Makefile | 17 +- .../bpf/map_tests/map_in_map_batch_ops.c | 2 +- .../selftests/bpf/prog_tests/attach_probe.c | 10 +- .../selftests/bpf/prog_tests/bpf_iter.c | 8 +- .../selftests/bpf/prog_tests/bpf_obj_id.c | 20 +- .../selftests/bpf/prog_tests/bpf_tcp_ca.c | 3 + tools/testing/selftests/bpf/prog_tests/btf.c | 24 +-- .../selftests/bpf/prog_tests/btf_map_in_map.c | 2 +- .../selftests/bpf/prog_tests/check_mtu.c | 2 +- .../selftests/bpf/prog_tests/enable_stats.c | 2 +- .../selftests/bpf/prog_tests/fexit_bpf2bpf.c | 14 +- .../bpf/prog_tests/flow_dissector_reattach.c | 10 +- .../bpf/prog_tests/libbpf_get_fd_by_id_opts.c | 4 +- .../selftests/bpf/prog_tests/lsm_cgroup.c | 3 +- .../selftests/bpf/prog_tests/metadata.c | 8 +- tools/testing/selftests/bpf/prog_tests/mmap.c | 2 +- .../selftests/bpf/prog_tests/perf_link.c | 2 +- .../selftests/bpf/prog_tests/pinning.c | 2 +- .../selftests/bpf/prog_tests/prog_run_opts.c | 2 +- .../selftests/bpf/prog_tests/recursion.c | 4 +- .../selftests/bpf/prog_tests/send_signal.c | 2 + .../selftests/bpf/prog_tests/sockmap_basic.c | 6 +- .../bpf/prog_tests/task_local_storage.c | 8 +- .../testing/selftests/bpf/prog_tests/tc_bpf.c | 4 +- .../bpf/prog_tests/tp_attach_query.c | 9 +- .../bpf/prog_tests/unpriv_bpf_disabled.c | 8 +- .../bpf/prog_tests/uprobe_autoattach.c | 14 +- .../selftests/bpf/prog_tests/verif_stats.c | 5 +- .../selftests/bpf/prog_tests/xdp_attach.c | 4 +- .../selftests/bpf/prog_tests/xdp_bonding.c | 3 + .../bpf/prog_tests/xdp_cpumap_attach.c | 8 +- .../bpf/prog_tests/xdp_devmap_attach.c | 8 +- .../selftests/bpf/prog_tests/xdp_info.c | 2 +- .../selftests/bpf/prog_tests/xdp_link.c | 10 +- .../selftests/bpf/progs/test_attach_probe.c | 11 +- .../bpf/progs/test_uprobe_autoattach.c | 16 +- tools/testing/selftests/bpf/test_maps.c | 2 +- .../selftests/bpf/test_skb_cgroup_id_user.c | 2 +- .../bpf/test_tcp_check_syncookie_user.c | 2 +- tools/testing/selftests/bpf/test_verifier.c | 8 +- tools/testing/selftests/bpf/testing_helpers.c | 2 +- tools/testing/selftests/bpf/xdp_synproxy.c | 15 +- 72 files changed, 478 insertions(+), 211 deletions(-) -- 2.39.1
