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-rw-r--r--tools/lib/bpf/libbpf.c160
-rw-r--r--tools/lib/bpf/libbpf.h23
-rw-r--r--tools/lib/bpf/libbpf.map1
3 files changed, 184 insertions, 0 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 1ca520a29fdb..f3a31478e23b 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -8610,6 +8610,7 @@ static int attach_kprobe(const struct bpf_program *prog, long cookie, struct bpf
static int attach_tp(const struct bpf_program *prog, long cookie, struct bpf_link **link);
static int attach_raw_tp(const struct bpf_program *prog, long cookie, struct bpf_link **link);
static int attach_trace(const struct bpf_program *prog, long cookie, struct bpf_link **link);
+static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link);
static int attach_lsm(const struct bpf_program *prog, long cookie, struct bpf_link **link);
static int attach_iter(const struct bpf_program *prog, long cookie, struct bpf_link **link);
@@ -8621,6 +8622,8 @@ static const struct bpf_sec_def section_defs[] = {
SEC_DEF("uprobe/", KPROBE, 0, SEC_NONE),
SEC_DEF("kretprobe/", KPROBE, 0, SEC_NONE, attach_kprobe),
SEC_DEF("uretprobe/", KPROBE, 0, SEC_NONE),
+ SEC_DEF("kprobe.multi/", KPROBE, BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi),
+ SEC_DEF("kretprobe.multi/", KPROBE, BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi),
SEC_DEF("tc", SCHED_CLS, 0, SEC_NONE),
SEC_DEF("classifier", SCHED_CLS, 0, SEC_NONE | SEC_SLOPPY_PFX | SEC_DEPRECATED),
SEC_DEF("action", SCHED_ACT, 0, SEC_NONE | SEC_SLOPPY_PFX),
@@ -10224,6 +10227,139 @@ struct bpf_link *bpf_program__attach_kprobe(const struct bpf_program *prog,
return bpf_program__attach_kprobe_opts(prog, func_name, &opts);
}
+/* Adapted from perf/util/string.c */
+static bool glob_match(const char *str, const char *pat)
+{
+ while (*str && *pat && *pat != '*') {
+ if (*pat == '?') { /* Matches any single character */
+ str++;
+ pat++;
+ continue;
+ }
+ if (*str != *pat)
+ return false;
+ str++;
+ pat++;
+ }
+ /* Check wild card */
+ if (*pat == '*') {
+ while (*pat == '*')
+ pat++;
+ if (!*pat) /* Tail wild card matches all */
+ return true;
+ while (*str)
+ if (glob_match(str++, pat))
+ return true;
+ }
+ return !*str && !*pat;
+}
+
+struct kprobe_multi_resolve {
+ const char *pattern;
+ unsigned long *addrs;
+ size_t cap;
+ size_t cnt;
+};
+
+static int
+resolve_kprobe_multi_cb(unsigned long long sym_addr, char sym_type,
+ const char *sym_name, void *ctx)
+{
+ struct kprobe_multi_resolve *res = ctx;
+ int err;
+
+ if (!glob_match(sym_name, res->pattern))
+ return 0;
+
+ err = libbpf_ensure_mem((void **) &res->addrs, &res->cap, sizeof(unsigned long),
+ res->cnt + 1);
+ if (err)
+ return err;
+
+ res->addrs[res->cnt++] = (unsigned long) sym_addr;
+ return 0;
+}
+
+struct bpf_link *
+bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog,
+ const char *pattern,
+ const struct bpf_kprobe_multi_opts *opts)
+{
+ LIBBPF_OPTS(bpf_link_create_opts, lopts);
+ struct kprobe_multi_resolve res = {
+ .pattern = pattern,
+ };
+ struct bpf_link *link = NULL;
+ char errmsg[STRERR_BUFSIZE];
+ const unsigned long *addrs;
+ int err, link_fd, prog_fd;
+ const __u64 *cookies;
+ const char **syms;
+ bool retprobe;
+ size_t cnt;
+
+ if (!OPTS_VALID(opts, bpf_kprobe_multi_opts))
+ return libbpf_err_ptr(-EINVAL);
+
+ syms = OPTS_GET(opts, syms, false);
+ addrs = OPTS_GET(opts, addrs, false);
+ cnt = OPTS_GET(opts, cnt, false);
+ cookies = OPTS_GET(opts, cookies, false);
+
+ if (!pattern && !addrs && !syms)
+ return libbpf_err_ptr(-EINVAL);
+ if (pattern && (addrs || syms || cookies || cnt))
+ return libbpf_err_ptr(-EINVAL);
+ if (!pattern && !cnt)
+ return libbpf_err_ptr(-EINVAL);
+ if (addrs && syms)
+ return libbpf_err_ptr(-EINVAL);
+
+ if (pattern) {
+ err = libbpf_kallsyms_parse(resolve_kprobe_multi_cb, &res);
+ if (err)
+ goto error;
+ if (!res.cnt) {
+ err = -ENOENT;
+ goto error;
+ }
+ addrs = res.addrs;
+ cnt = res.cnt;
+ }
+
+ retprobe = OPTS_GET(opts, retprobe, false);
+
+ lopts.kprobe_multi.syms = syms;
+ lopts.kprobe_multi.addrs = addrs;
+ lopts.kprobe_multi.cookies = cookies;
+ lopts.kprobe_multi.cnt = cnt;
+ lopts.kprobe_multi.flags = retprobe ? BPF_F_KPROBE_MULTI_RETURN : 0;
+
+ link = calloc(1, sizeof(*link));
+ if (!link) {
+ err = -ENOMEM;
+ goto error;
+ }
+ link->detach = &bpf_link__detach_fd;
+
+ prog_fd = bpf_program__fd(prog);
+ link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_KPROBE_MULTI, &lopts);
+ if (link_fd < 0) {
+ err = -errno;
+ pr_warn("prog '%s': failed to attach: %s\n",
+ prog->name, libbpf_strerror_r(err, errmsg, sizeof(errmsg)));
+ goto error;
+ }
+ link->fd = link_fd;
+ free(res.addrs);
+ return link;
+
+error:
+ free(link);
+ free(res.addrs);
+ return libbpf_err_ptr(err);
+}
+
static int attach_kprobe(const struct bpf_program *prog, long cookie, struct bpf_link **link)
{
DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, opts);
@@ -10255,6 +10391,30 @@ static int attach_kprobe(const struct bpf_program *prog, long cookie, struct bpf
return libbpf_get_error(*link);
}
+static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link)
+{
+ LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
+ const char *spec;
+ char *pattern;
+ int n;
+
+ opts.retprobe = str_has_pfx(prog->sec_name, "kretprobe.multi/");
+ if (opts.retprobe)
+ spec = prog->sec_name + sizeof("kretprobe.multi/") - 1;
+ else
+ spec = prog->sec_name + sizeof("kprobe.multi/") - 1;
+
+ n = sscanf(spec, "%m[a-zA-Z0-9_.*?]", &pattern);
+ if (n < 1) {
+ pr_warn("kprobe multi pattern is invalid: %s\n", pattern);
+ return -EINVAL;
+ }
+
+ *link = bpf_program__attach_kprobe_multi_opts(prog, pattern, &opts);
+ free(pattern);
+ return libbpf_get_error(*link);
+}
+
static void gen_uprobe_legacy_event_name(char *buf, size_t buf_sz,
const char *binary_path, uint64_t offset)
{
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index c1b0c2ef14d8..d5239fb4abdc 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -425,6 +425,29 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
const char *func_name,
const struct bpf_kprobe_opts *opts);
+struct bpf_kprobe_multi_opts {
+ /* size of this struct, for forward/backward compatibility */
+ size_t sz;
+ /* array of function symbols to attach */
+ const char **syms;
+ /* array of function addresses to attach */
+ const unsigned long *addrs;
+ /* array of user-provided values fetchable through bpf_get_attach_cookie */
+ const __u64 *cookies;
+ /* number of elements in syms/addrs/cookies arrays */
+ size_t cnt;
+ /* create return kprobes */
+ bool retprobe;
+ size_t :0;
+};
+
+#define bpf_kprobe_multi_opts__last_field retprobe
+
+LIBBPF_API struct bpf_link *
+bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog,
+ const char *pattern,
+ const struct bpf_kprobe_multi_opts *opts);
+
struct bpf_uprobe_opts {
/* size of this struct, for forward/backward compatiblity */
size_t sz;
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index df1b947792c8..554c56e6e5d3 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -444,4 +444,5 @@ LIBBPF_0.8.0 {
global:
libbpf_register_prog_handler;
libbpf_unregister_prog_handler;
+ bpf_program__attach_kprobe_multi_opts;
} LIBBPF_0.7.0;