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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
selftests/bpf: Adding test for arg dereference in extension trace
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 <jolsa@kernel.org>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/160138355603.48470.9072073357530773228.stgit@toke.dk
authored by
Jiri Olsa
and committed by
Alexei Starovoitov
17d3f386
f6429476
+154
+111
tools/testing/selftests/bpf/prog_tests/trace_ext.c
+111
tools/testing/selftests/bpf/prog_tests/trace_ext.c
···
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// SPDX-License-Identifier: GPL-2.0
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#define _GNU_SOURCE
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#include <test_progs.h>
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#include <network_helpers.h>
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#include <sys/stat.h>
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#include <linux/sched.h>
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#include <sys/syscall.h>
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#include "test_pkt_md_access.skel.h"
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#include "test_trace_ext.skel.h"
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#include "test_trace_ext_tracing.skel.h"
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static __u32 duration;
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void test_trace_ext(void)
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{
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struct test_pkt_md_access *skel_pkt = NULL;
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struct test_trace_ext_tracing *skel_trace = NULL;
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struct test_trace_ext_tracing__bss *bss_trace;
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struct test_trace_ext *skel_ext = NULL;
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struct test_trace_ext__bss *bss_ext;
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int err, pkt_fd, ext_fd;
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struct bpf_program *prog;
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char buf[100];
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__u32 retval;
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__u64 len;
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/* open/load/attach test_pkt_md_access */
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skel_pkt = test_pkt_md_access__open_and_load();
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if (CHECK(!skel_pkt, "setup", "classifier/test_pkt_md_access open failed\n"))
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goto cleanup;
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err = test_pkt_md_access__attach(skel_pkt);
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if (CHECK(err, "setup", "classifier/test_pkt_md_access attach failed: %d\n", err))
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goto cleanup;
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prog = skel_pkt->progs.test_pkt_md_access;
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pkt_fd = bpf_program__fd(prog);
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/* open extension */
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skel_ext = test_trace_ext__open();
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if (CHECK(!skel_ext, "setup", "freplace/test_pkt_md_access open failed\n"))
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goto cleanup;
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/* set extension's attach target - test_pkt_md_access */
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prog = skel_ext->progs.test_pkt_md_access_new;
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bpf_program__set_attach_target(prog, pkt_fd, "test_pkt_md_access");
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/* load/attach extension */
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err = test_trace_ext__load(skel_ext);
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if (CHECK(err, "setup", "freplace/test_pkt_md_access load failed\n")) {
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libbpf_strerror(err, buf, sizeof(buf));
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fprintf(stderr, "%s\n", buf);
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goto cleanup;
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}
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err = test_trace_ext__attach(skel_ext);
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if (CHECK(err, "setup", "freplace/test_pkt_md_access attach failed: %d\n", err))
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goto cleanup;
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prog = skel_ext->progs.test_pkt_md_access_new;
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ext_fd = bpf_program__fd(prog);
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/* open tracing */
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skel_trace = test_trace_ext_tracing__open();
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if (CHECK(!skel_trace, "setup", "tracing/test_pkt_md_access_new open failed\n"))
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goto cleanup;
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/* set tracing's attach target - fentry */
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prog = skel_trace->progs.fentry;
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bpf_program__set_attach_target(prog, ext_fd, "test_pkt_md_access_new");
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/* set tracing's attach target - fexit */
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prog = skel_trace->progs.fexit;
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bpf_program__set_attach_target(prog, ext_fd, "test_pkt_md_access_new");
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/* load/attach tracing */
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err = test_trace_ext_tracing__load(skel_trace);
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if (CHECK(err, "setup", "tracing/test_pkt_md_access_new load failed\n")) {
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libbpf_strerror(err, buf, sizeof(buf));
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fprintf(stderr, "%s\n", buf);
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goto cleanup;
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}
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err = test_trace_ext_tracing__attach(skel_trace);
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if (CHECK(err, "setup", "tracing/test_pkt_md_access_new attach failed: %d\n", err))
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goto cleanup;
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/* trigger the test */
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err = bpf_prog_test_run(pkt_fd, 1, &pkt_v4, sizeof(pkt_v4),
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NULL, NULL, &retval, &duration);
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CHECK(err || retval, "run", "err %d errno %d retval %d\n", err, errno, retval);
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bss_ext = skel_ext->bss;
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bss_trace = skel_trace->bss;
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len = bss_ext->ext_called;
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CHECK(bss_ext->ext_called == 0,
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"check", "failed to trigger freplace/test_pkt_md_access\n");
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CHECK(bss_trace->fentry_called != len,
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"check", "failed to trigger fentry/test_pkt_md_access_new\n");
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CHECK(bss_trace->fexit_called != len,
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"check", "failed to trigger fexit/test_pkt_md_access_new\n");
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cleanup:
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test_trace_ext_tracing__destroy(skel_trace);
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test_trace_ext__destroy(skel_ext);
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test_pkt_md_access__destroy(skel_pkt);
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}
+18
tools/testing/selftests/bpf/progs/test_trace_ext.c
+18
tools/testing/selftests/bpf/progs/test_trace_ext.c
···
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// SPDX-License-Identifier: GPL-2.0
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// Copyright (c) 2019 Facebook
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#include <linux/bpf.h>
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#include <stdbool.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_endian.h>
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#include <bpf/bpf_tracing.h>
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__u64 ext_called = 0;
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SEC("freplace/test_pkt_md_access")
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int test_pkt_md_access_new(struct __sk_buff *skb)
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{
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ext_called = skb->len;
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return 0;
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}
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char _license[] SEC("license") = "GPL";
+25
tools/testing/selftests/bpf/progs/test_trace_ext_tracing.c
+25
tools/testing/selftests/bpf/progs/test_trace_ext_tracing.c
···
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// SPDX-License-Identifier: GPL-2.0
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#include "vmlinux.h"
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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__u64 fentry_called = 0;
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SEC("fentry/test_pkt_md_access_new")
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int BPF_PROG(fentry, struct sk_buff *skb)
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{
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fentry_called = skb->len;
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return 0;
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}
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__u64 fexit_called = 0;
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SEC("fexit/test_pkt_md_access_new")
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int BPF_PROG(fexit, struct sk_buff *skb)
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{
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fexit_called = skb->len;
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return 0;
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}
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char _license[] SEC("license") = "GPL";