From 17d3f386757609223aa02342d29526daa67efafc Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 29 Sep 2020 14:45:56 +0200 Subject: [PATCH] selftests/bpf: Adding test for arg dereference in extension trace MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Adding test that setup following program: SEC("classifier/test_pkt_md_access") int test_pkt_md_access(struct __sk_buff *skb) with its extension: SEC("freplace/test_pkt_md_access") int test_pkt_md_access_new(struct __sk_buff *skb) and tracing that extension with: SEC("fentry/test_pkt_md_access_new") int BPF_PROG(fentry, struct sk_buff *skb) The test verifies that the tracing program can dereference skb argument properly. Signed-off-by: Jiri Olsa Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/160138355603.48470.9072073357530773228.stgit@toke.dk --- tools/testing/selftests/bpf/prog_tests/trace_ext.c | 111 +++++++++++++++++++++ tools/testing/selftests/bpf/progs/test_trace_ext.c | 18 ++++ .../selftests/bpf/progs/test_trace_ext_tracing.c | 25 +++++ 3 files changed, 154 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/trace_ext.c create mode 100644 tools/testing/selftests/bpf/progs/test_trace_ext.c create mode 100644 tools/testing/selftests/bpf/progs/test_trace_ext_tracing.c diff --git a/tools/testing/selftests/bpf/prog_tests/trace_ext.c b/tools/testing/selftests/bpf/prog_tests/trace_ext.c new file mode 100644 index 0000000..924441d --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/trace_ext.c @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define _GNU_SOURCE +#include +#include +#include +#include +#include + +#include "test_pkt_md_access.skel.h" +#include "test_trace_ext.skel.h" +#include "test_trace_ext_tracing.skel.h" + +static __u32 duration; + +void test_trace_ext(void) +{ + struct test_pkt_md_access *skel_pkt = NULL; + struct test_trace_ext_tracing *skel_trace = NULL; + struct test_trace_ext_tracing__bss *bss_trace; + struct test_trace_ext *skel_ext = NULL; + struct test_trace_ext__bss *bss_ext; + int err, pkt_fd, ext_fd; + struct bpf_program *prog; + char buf[100]; + __u32 retval; + __u64 len; + + /* open/load/attach test_pkt_md_access */ + skel_pkt = test_pkt_md_access__open_and_load(); + if (CHECK(!skel_pkt, "setup", "classifier/test_pkt_md_access open failed\n")) + goto cleanup; + + err = test_pkt_md_access__attach(skel_pkt); + if (CHECK(err, "setup", "classifier/test_pkt_md_access attach failed: %d\n", err)) + goto cleanup; + + prog = skel_pkt->progs.test_pkt_md_access; + pkt_fd = bpf_program__fd(prog); + + /* open extension */ + skel_ext = test_trace_ext__open(); + if (CHECK(!skel_ext, "setup", "freplace/test_pkt_md_access open failed\n")) + goto cleanup; + + /* set extension's attach target - test_pkt_md_access */ + prog = skel_ext->progs.test_pkt_md_access_new; + bpf_program__set_attach_target(prog, pkt_fd, "test_pkt_md_access"); + + /* load/attach extension */ + err = test_trace_ext__load(skel_ext); + if (CHECK(err, "setup", "freplace/test_pkt_md_access load failed\n")) { + libbpf_strerror(err, buf, sizeof(buf)); + fprintf(stderr, "%s\n", buf); + goto cleanup; + } + + err = test_trace_ext__attach(skel_ext); + if (CHECK(err, "setup", "freplace/test_pkt_md_access attach failed: %d\n", err)) + goto cleanup; + + prog = skel_ext->progs.test_pkt_md_access_new; + ext_fd = bpf_program__fd(prog); + + /* open tracing */ + skel_trace = test_trace_ext_tracing__open(); + if (CHECK(!skel_trace, "setup", "tracing/test_pkt_md_access_new open failed\n")) + goto cleanup; + + /* set tracing's attach target - fentry */ + prog = skel_trace->progs.fentry; + bpf_program__set_attach_target(prog, ext_fd, "test_pkt_md_access_new"); + + /* set tracing's attach target - fexit */ + prog = skel_trace->progs.fexit; + bpf_program__set_attach_target(prog, ext_fd, "test_pkt_md_access_new"); + + /* load/attach tracing */ + err = test_trace_ext_tracing__load(skel_trace); + if (CHECK(err, "setup", "tracing/test_pkt_md_access_new load failed\n")) { + libbpf_strerror(err, buf, sizeof(buf)); + fprintf(stderr, "%s\n", buf); + goto cleanup; + } + + err = test_trace_ext_tracing__attach(skel_trace); + if (CHECK(err, "setup", "tracing/test_pkt_md_access_new attach failed: %d\n", err)) + goto cleanup; + + /* trigger the test */ + err = bpf_prog_test_run(pkt_fd, 1, &pkt_v4, sizeof(pkt_v4), + NULL, NULL, &retval, &duration); + CHECK(err || retval, "run", "err %d errno %d retval %d\n", err, errno, retval); + + bss_ext = skel_ext->bss; + bss_trace = skel_trace->bss; + + len = bss_ext->ext_called; + + CHECK(bss_ext->ext_called == 0, + "check", "failed to trigger freplace/test_pkt_md_access\n"); + CHECK(bss_trace->fentry_called != len, + "check", "failed to trigger fentry/test_pkt_md_access_new\n"); + CHECK(bss_trace->fexit_called != len, + "check", "failed to trigger fexit/test_pkt_md_access_new\n"); + +cleanup: + test_trace_ext_tracing__destroy(skel_trace); + test_trace_ext__destroy(skel_ext); + test_pkt_md_access__destroy(skel_pkt); +} diff --git a/tools/testing/selftests/bpf/progs/test_trace_ext.c b/tools/testing/selftests/bpf/progs/test_trace_ext.c new file mode 100644 index 0000000..d19a634 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_trace_ext.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook +#include +#include +#include +#include +#include + +__u64 ext_called = 0; + +SEC("freplace/test_pkt_md_access") +int test_pkt_md_access_new(struct __sk_buff *skb) +{ + ext_called = skb->len; + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/test_trace_ext_tracing.c b/tools/testing/selftests/bpf/progs/test_trace_ext_tracing.c new file mode 100644 index 0000000..52f3baf --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_trace_ext_tracing.c @@ -0,0 +1,25 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "vmlinux.h" +#include +#include + +__u64 fentry_called = 0; + +SEC("fentry/test_pkt_md_access_new") +int BPF_PROG(fentry, struct sk_buff *skb) +{ + fentry_called = skb->len; + return 0; +} + +__u64 fexit_called = 0; + +SEC("fexit/test_pkt_md_access_new") +int BPF_PROG(fexit, struct sk_buff *skb) +{ + fexit_called = skb->len; + return 0; +} + +char _license[] SEC("license") = "GPL"; -- 2.7.4