Add a test to demonstrate that str key doesn't care about the content of unused part in hash-table key. Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx> --- .../selftests/bpf/prog_tests/str_key.c | 71 ++++++++++++++++++ tools/testing/selftests/bpf/progs/str_key.c | 75 +++++++++++++++++++ 2 files changed, 146 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/str_key.c create mode 100644 tools/testing/selftests/bpf/progs/str_key.c diff --git a/tools/testing/selftests/bpf/prog_tests/str_key.c b/tools/testing/selftests/bpf/prog_tests/str_key.c new file mode 100644 index 000000000000..998f12f8b919 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/str_key.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2022. Huawei Technologies Co., Ltd */ +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> +#include <test_progs.h> +#include "str_key.skel.h" + +#define HTAB_NAME_SIZE 64 + +struct str_htab_key { + struct bpf_str_key_stor name; + char raw[HTAB_NAME_SIZE]; +}; + +static int setup_maps(struct str_key *skel, const char *name, unsigned int value) +{ + struct str_htab_key key; + int fd, err; + + memset(&key, 0, sizeof(key)); + strncpy(key.raw, name, sizeof(key.raw) - 1); + key.name.len = strlen(name) + 1; + + fd = bpf_map__fd(skel->maps.str_htab); + err = bpf_map_update_elem(fd, &key, &value, BPF_NOEXIST); + if (!ASSERT_OK(err, "str htab add")) + return -EINVAL; + + fd = bpf_map__fd(skel->maps.byte_htab); + err = bpf_map_update_elem(fd, key.raw, &value, BPF_NOEXIST); + if (!ASSERT_OK(err, "byte htab add")) + return -EINVAL; + + return 0; +} + +void test_str_key(void) +{ + const char *name = "/tmp/str_key_test"; + struct str_key *skel; + unsigned int value; + int err, fd; + + skel = str_key__open_and_load(); + if (!ASSERT_OK_PTR(skel, "open_load str key")) + return; + + srandom(time(NULL)); + value = random(); + if (setup_maps(skel, name, value)) + goto out; + + skel->bss->pid = getpid(); + err = str_key__attach(skel); + if (!ASSERT_OK(err, "attach")) + goto out; + + fd = open(name, O_RDONLY | O_CREAT, 0644); + if (!ASSERT_GE(fd, 0, "open tmp file")) + goto out; + close(fd); + unlink(name); + + ASSERT_EQ(skel->bss->str_htab_value, value, "str htab find"); + ASSERT_EQ(skel->bss->byte_htab_value, -1, "byte htab find"); + +out: + str_key__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/str_key.c b/tools/testing/selftests/bpf/progs/str_key.c new file mode 100644 index 000000000000..4d5a4b7cf183 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/str_key.c @@ -0,0 +1,75 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2022. Huawei Technologies Co., Ltd */ +#include <linux/types.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_core_read.h> +#include <bpf/bpf_tracing.h> + +char _license[] SEC("license") = "GPL"; + +struct path { +} __attribute__((preserve_access_index)); + +struct file { + struct path f_path; +} __attribute__((preserve_access_index)); + +#define HTAB_NAME_SIZE 64 + +struct str_htab_key { + struct bpf_str_key_stor name; + char raw[HTAB_NAME_SIZE]; +}; + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 1); + __type(key, struct str_htab_key); + __type(value, __u32); + __uint(map_flags, BPF_F_STR_IN_KEY); +} str_htab SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 1); + __uint(key_size, HTAB_NAME_SIZE); + __uint(value_size, sizeof(__u32)); +} byte_htab SEC(".maps"); + +int pid = 0; +unsigned int str_htab_value = 0; +unsigned int byte_htab_value = 0; + +SEC("fentry/filp_close") +int BPF_PROG(filp_close, struct file *filp) +{ + struct path *p = &filp->f_path; + struct str_htab_key key; + unsigned int *value; + int len; + + if (bpf_get_current_pid_tgid() >> 32 != pid) + return 0; + + __builtin_memset(key.raw, 0, sizeof(key.raw)); + len = bpf_d_path(p, key.raw, sizeof(key.raw)); + if (len < 0 || len > sizeof(key.raw)) + return 0; + + key.name.hash = 0; + key.name.len = len; + value = bpf_map_lookup_elem(&str_htab, &key); + if (value) + str_htab_value = *value; + else + str_htab_value = -1; + + value = bpf_map_lookup_elem(&byte_htab, key.raw); + if (value) + byte_htab_value = *value; + else + byte_htab_value = -1; + + return 0; +} -- 2.25.4