From e77aa19957b5f38fd47dc8de0a701ecf8482697b Mon Sep 17 00:00:00 2001 From: Paul Buetow Date: Fri, 29 May 2026 10:02:18 +0300 Subject: test(epoll_create): lock in epoll_create1 args[0] flags capture Audited epoll_create/epoll_create1 against man 2 epoll_create. Implementation already correct: both classify as KindEventfd (fd-creating), epoll_create(size) hardcodes flags=0 (no flags arg), epoll_create1(flags) reads ctx->args[0], and exit captures the returned fd via ev->ret. Add FormatEpollCreate1/FormatExitEpollCreate1 fixtures and TestGenerateEpollCreate1HandlerUsesArg0Flags as the positive counterpart to the existing TestGenerateEpollCreateHandlerUsesZeroFlags negative test, asserting the enter handler captures args[0] as flags rather than 0. Co-Authored-By: Claude Opus 4.8 --- internal/generate/codegen_test.go | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'internal/generate/codegen_test.go') diff --git a/internal/generate/codegen_test.go b/internal/generate/codegen_test.go index d74939b..b0e6f75 100644 --- a/internal/generate/codegen_test.go +++ b/internal/generate/codegen_test.go @@ -397,6 +397,24 @@ func TestGenerateEpollCreateHandlerUsesZeroFlags(t *testing.T) { requireContains(t, output, "ev->ret = ctx->ret;") } +func TestGenerateEpollCreate1HandlerUsesArg0Flags(t *testing.T) { + output := generateFromPair(t, FormatEpollCreate1, FormatExitEpollCreate1) + + requireContains(t, output, "struct eventfd_event *ev") + requireContains(t, output, "ev->event_type = ENTER_EVENTFD_EVENT;") + requireContains(t, output, "ev->trace_id = SYS_ENTER_EPOLL_CREATE1;") + // epoll_create1(flags) carries its flags (e.g. EPOLL_CLOEXEC) in args[0]; + // the generated enter handler must capture it rather than hardcoding 0. + requireContains(t, output, "__s32 flags = (__s32)ctx->args[0];") + if strings.Contains(output, "__s32 flags = 0;\n bpf_map_update_elem") { + t.Error("epoll_create1 enter handler must read ctx->args[0] as flags, not 0") + } + requireContains(t, output, "ev->ret = -1;") + requireContains(t, output, "SEC(\"tracepoint/syscalls/sys_exit_epoll_create1\")") + requireContains(t, output, "ev->event_type = EXIT_EVENTFD_EVENT;") + requireContains(t, output, "ev->ret = ctx->ret;") +} + func TestGeneratePidfdOpenHandlerUsesArg1Flags(t *testing.T) { output := generateFromPair(t, FormatPidfdOpen, FormatExitPidfdOpen) -- cgit v1.2.3