Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
selftests/bpf: Add tests for exclusive maps
Check if access is denied to another program for an exclusive map
Signed-off-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/r/20250914215141.15144-6-kpsingh@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
authored by
KP Singh
and committed by
Alexei Starovoitov
6c850cbc
567010a5
+88
+54
tools/testing/selftests/bpf/prog_tests/map_excl.c
+54
tools/testing/selftests/bpf/prog_tests/map_excl.c
···
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// SPDX-License-Identifier: GPL-2.0
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/* Copyright (C) 2025 Google LLC. */
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#define _GNU_SOURCE
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#include <unistd.h>
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#include <sys/syscall.h>
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#include <test_progs.h>
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#include <bpf/btf.h>
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#include "map_excl.skel.h"
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static void test_map_excl_allowed(void)
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{
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struct map_excl *skel = map_excl__open();
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int err;
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err = bpf_map__set_exclusive_program(skel->maps.excl_map, skel->progs.should_have_access);
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if (!ASSERT_OK(err, "bpf_map__set_exclusive_program"))
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goto out;
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bpf_program__set_autoload(skel->progs.should_have_access, true);
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bpf_program__set_autoload(skel->progs.should_not_have_access, false);
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err = map_excl__load(skel);
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ASSERT_OK(err, "map_excl__load");
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out:
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map_excl__destroy(skel);
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}
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static void test_map_excl_denied(void)
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{
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struct map_excl *skel = map_excl__open();
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int err;
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err = bpf_map__set_exclusive_program(skel->maps.excl_map, skel->progs.should_have_access);
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if (!ASSERT_OK(err, "bpf_map__make_exclusive"))
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goto out;
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bpf_program__set_autoload(skel->progs.should_have_access, false);
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bpf_program__set_autoload(skel->progs.should_not_have_access, true);
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err = map_excl__load(skel);
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ASSERT_EQ(err, -EACCES, "exclusive map access not denied\n");
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out:
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map_excl__destroy(skel);
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}
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void test_map_excl(void)
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{
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if (test__start_subtest("map_excl_allowed"))
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test_map_excl_allowed();
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if (test__start_subtest("map_excl_denied"))
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test_map_excl_denied();
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}
+34
tools/testing/selftests/bpf/progs/map_excl.c
+34
tools/testing/selftests/bpf/progs/map_excl.c
···
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// SPDX-License-Identifier: GPL-2.0
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/* Copyright (C) 2025 Google LLC. */
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#include <linux/bpf.h>
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#include <time.h>
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#include <bpf/bpf_helpers.h>
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#include "bpf_misc.h"
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__type(key, __u32);
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__type(value, __u32);
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__uint(max_entries, 1);
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} excl_map SEC(".maps");
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char _license[] SEC("license") = "GPL";
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SEC("?fentry.s/" SYS_PREFIX "sys_getpgid")
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int should_have_access(void *ctx)
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{
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int key = 0, value = 0xdeadbeef;
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bpf_map_update_elem(&excl_map, &key, &value, 0);
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return 0;
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}
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SEC("?fentry.s/" SYS_PREFIX "sys_getpgid")
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int should_not_have_access(void *ctx)
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{
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int key = 0, value = 0xdeadbeef;
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bpf_map_update_elem(&excl_map, &key, &value, 0);
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return 0;
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}