en Copyright 2015 Java http://kernelsources.org:8080/source/history/linux/tools/testing/selftests/landlock/trace_fs_test.c#d41d0021a6ea3e9fcd14126a00fead47f981c46e landlock: Test trace path output boundariesUse focused KUnit tests to exercise the renderer's internal boundary andcomposition contracts with synthetic scratch states, including bothsibling-helper evaluation orders. Check the exact output andreservation boundaries, including a four-byte octal escape accepted atexact capacity and rejected one byte short. Also verify an unchangedcursor on failure, that bracketed process names and embedded NUL bytesremain data, and that input ellipsis bytes are escaped rather thanmistaken for the raw truncation marker.The composition test requires generic trace output helpers. EnableCONFIG_FTRACE and CONFIG_SCHED_TRACER because the latter selects theotherwise-hidden CONFIG_TRACING support required bytrace_print_flags_seq().Use kselftests to exercise the complete tracefs path for both affectedfilesystem events. A valid path containing 2640 spaces exceeds thescratch output budget. Require its escaped prefix to end in the rawUTF-8 ellipsis while access_rights and blockers remain intact.This division keeps the exact safety contract compiler-independent whileproving that real tracepoints preserve their surrounding symbolicfields. The end-to-end assertions fail after a full fix revert withboth GCC and Clang, while the composition KUnit test fails if thescratch reserve is removed.Cc: Günther Noack <gnoack@google.com>Link: https://patch.msgid.link/20260907154401.124362-2-mic@digikod.netSigned-off-by: Mickaël Salaün <mic@digikod.net> List of files: /linux/tools/testing/selftests/landlock/trace_fs_test.c Mon, 07 Sep 2026 17:43:59 +0200 Mickaël Salaün <mic@digikod.net> http://kernelsources.org:8080/source/history/linux/tools/testing/selftests/landlock/trace_fs_test.c#30478db56cf03db2f6ecd0e0d133b12c3fe83a57 selftests/landlock: Add filesystem tracepoint testsAdd filesystem-specific trace tests in a dedicated file, following theaudit-test pattern of living alongside each subsystem's functionaltests.trace_fs_test.c verifies that the add_rule_fs, check_rule_fs, anddeny_access_fs events fire with the correct fields on matching rules anddenied accesses, that check_rule_fs does not fire for unhandled accesstypes, and that no event fires without a sandbox. A denial covered by aquiet rule still emits a deny_access_fs event but with logged=0, thesame suppression verdict audit applies; because that verdict must notdepend on CONFIG_AUDIT, the test also runs under a tracepoints-onlybuild.Add trace_layout1 fixture tests in fs_test.c that reuse the layout1hierarchy to verify the per-layer grants field: field values, multi-rulepathwalk short-circuit, request intersection, the optional truncateright surfacing in the request and grants, and an empty grants set froma rule that grants none of the requested rights.Cc: Günther Noack <gnoack@google.com>Cc: Tingmao Wang <m@maowtm.org>Link: https://patch.msgid.link/20260811094338.288094-16-mic@digikod.netSigned-off-by: Mickaël Salaün <mic@digikod.net> List of files: /linux/tools/testing/selftests/landlock/trace_fs_test.c Tue, 11 Aug 2026 11:43:29 +0200 Mickaël Salaün <mic@digikod.net>