[PATCH bpf v4 00/20] selftests/bpf: Fixes for userspace ASAN

[Ihor Solodrai]

This series includes various fixes aiming to enable test_progs run
with userspace address sanitizer on BPF CI.

The first five patches add a simplified implementation of strscpy() to
selftests/bpf and then replace strcpy/strncpy usages across the tests
with it. See relevant discussions [1][2].

Patch #6 fixes the selftests/bpf/test_progs build with:

    SAN_CFLAGS="-fsanitize=address -fno-omit-frame-pointer"

The subsequent patches fix bugs reported by the address sanitizer on
attempt to run the tests.

[1] https://lore.kernel.org/bpf/CAADnVQ+9uw2_o388j43EWiAPdMB=3FLx2jq-9zRSvqrv-wgRag@xxxxxxxxxxxxxx/
[2] https://lore.kernel.org/bpf/20260220182011.802116-1-ihor.solodrai@xxxxxxxxx/

---

v3->v4:
  - combine strscpy and ASAN series into one (Alexei)
  - make the count arg of strscpy() optional via macro and fixup
    relevant call sites (Alexei)
  - remove strscpy_cat() from this series (Alexei)

v3: https://lore.kernel.org/bpf/20260220222604.1155148-1-ihor.solodrai@xxxxxxxxx/

v2->v3:
  - rebase on top of "selftests/bpf: Add and use strscpy()"
    - https://lore.kernel.org/bpf/20260220182011.802116-1-ihor.solodrai@xxxxxxxxx/
  - uprobe_multi_test.c: memset static struct child at the beginning
    of a test *and* zero out child->thread in release_child (patch #9,
    Mykyta)
  - nits in test_sysctl.c (patch #11, Eduard)
  - bpftool_helpers.c: update to use strscpy (patch #14, Alexei)
  - add __asan_on_error handler to still dump test logs even with ASAN
    build (patch #15, Mykyta)

v2: https://lore.kernel.org/bpf/20260218003041.1156774-1-ihor.solodrai@xxxxxxxxx/

v1->v2:
  - rebase on bpf (v1 was targeting bpf-next)
  - add ASAN flag handling in selftests/bpf/Makefile (Eduard)
  - don't override SIGSEGV handler in test_progs with ASAN (Eduard)
  - add error messages in detect_bpftool_path (Mykyta)
  - various nits (Eduard, Jiri, Mykyta, Alexis)

v1: https://lore.kernel.org/bpf/20260212011356.3266753-1-ihor.solodrai@xxxxxxxxx/

---

Ihor Solodrai (20):
  selftests/bpf: Add simple strscpy() implementation
  selftests/bpf: Replace strcpy() calls with strscpy()
  selftests/bpf: Replace strncpy() with strscpy()
  selftests/bpf: Use strscpy in bpftool_helpers.c
  selftests/bpf: Use memcpy() for bounded non-NULL-terminated copies
  selftests/bpf: Pass through build flags to bpftool and resolve_btfids
  resolve_btfids: Fix memory leaks reported by ASAN
  selftests/bpf: Add DENYLIST.asan
  selftests/bpf: Refactor bpf_get_ksyms() trace helper
  selftests/bpf: Fix memory leaks in tests
  selftests/bpf: Fix cleanup in check_fd_array_cnt__fd_array_too_big()
  veristat: Fix a memory leak for preset ENUMERATOR
  selftests/bpf: Fix use-after-free in xdp_metadata test
  selftests/bpf: Fix double thread join in uprobe_multi_test
  selftests/bpf: Fix resource leaks caused by missing cleanups
  selftests/bpf: Free bpf_object in test_sysctl
  selftests/bpf: Fix array bounds warning in jit_disasm_helpers
  selftests/bpf: Fix out-of-bounds array access bugs reported by ASAN
  selftests/bpf: Check BPFTOOL env var in detect_bpftool_path()
  selftests/bpf: Don't override SIGSEGV handler with ASAN

 tools/bpf/resolve_btfids/Makefile             |  7 +-
 tools/bpf/resolve_btfids/main.c               | 81 ++++++++++++-------
 tools/include/linux/args.h                    |  4 +
 tools/testing/selftests/bpf/DENYLIST.asan     |  3 +
 tools/testing/selftests/bpf/Makefile          | 13 ++-
 .../selftests/bpf/benchs/bench_trigger.c      | 14 ++--
 tools/testing/selftests/bpf/bpf_util.h        | 45 ++++++++---
 tools/testing/selftests/bpf/bpftool_helpers.c | 25 ++++--
 tools/testing/selftests/bpf/cgroup_helpers.c  |  2 +-
 .../selftests/bpf/jit_disasm_helpers.c        | 18 ++---
 tools/testing/selftests/bpf/network_helpers.c |  5 +-
 .../testing/selftests/bpf/prog_tests/align.c  |  2 +-
 .../selftests/bpf/prog_tests/bpf_iter.c       |  3 +-
 .../selftests/bpf/prog_tests/bpf_tcp_ca.c     |  2 +-
 .../bpf/prog_tests/cgrp_local_storage.c       |  4 +-
 .../selftests/bpf/prog_tests/ctx_rewrite.c    |  6 +-
 .../testing/selftests/bpf/prog_tests/dynptr.c |  5 +-
 .../selftests/bpf/prog_tests/fd_array.c       |  4 +-
 .../selftests/bpf/prog_tests/flow_dissector.c |  4 +-
 .../selftests/bpf/prog_tests/htab_update.c    |  1 +
 .../bpf/prog_tests/kmem_cache_iter.c          |  7 +-
 .../bpf/prog_tests/kprobe_multi_test.c        | 12 ++-
 .../selftests/bpf/prog_tests/lwt_seg6local.c  |  2 +-
 .../bpf/prog_tests/queue_stack_map.c          |  4 +-
 .../selftests/bpf/prog_tests/setget_sockopt.c |  2 +-
 .../bpf/prog_tests/skc_to_unix_sock.c         |  2 +-
 .../selftests/bpf/prog_tests/sockmap_basic.c  | 28 +++----
 .../selftests/bpf/prog_tests/sockmap_listen.c |  2 +-
 .../selftests/bpf/prog_tests/sockopt_sk.c     |  2 +-
 .../bpf/prog_tests/struct_ops_private_stack.c |  4 +-
 .../bpf/prog_tests/task_local_data.h          |  2 +-
 .../selftests/bpf/prog_tests/tc_opts.c        |  6 +-
 .../selftests/bpf/prog_tests/tc_redirect.c    |  2 +-
 .../selftests/bpf/prog_tests/test_sysctl.c    |  3 +
 .../selftests/bpf/prog_tests/test_tc_tunnel.c |  5 +-
 .../selftests/bpf/prog_tests/test_veristat.c  |  4 +-
 .../selftests/bpf/prog_tests/test_xsk.c       | 24 +++++-
 .../bpf/prog_tests/uprobe_multi_test.c        |  6 +-
 .../selftests/bpf/prog_tests/verifier_log.c   |  2 +-
 .../selftests/bpf/prog_tests/xdp_metadata.c   |  4 +-
 tools/testing/selftests/bpf/test_progs.c      | 38 ++++++---
 tools/testing/selftests/bpf/test_verifier.c   |  2 +-
 tools/testing/selftests/bpf/testing_helpers.c |  1 +
 tools/testing/selftests/bpf/trace_helpers.c   | 23 +++---
 tools/testing/selftests/bpf/trace_helpers.h   | 11 ++-
 tools/testing/selftests/bpf/veristat.c        |  2 +
 tools/testing/selftests/bpf/xdp_features.c    |  3 +-
 tools/testing/selftests/bpf/xdp_hw_metadata.c |  4 +-
 48 files changed, 291 insertions(+), 164 deletions(-)
 create mode 100644 tools/testing/selftests/bpf/DENYLIST.asan

-- 
2.53.0