diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index f6e5a0217841..6d2be53e4ba9 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -8630,6 +8630,7 @@ int bpf_program__set_log_buf(struct bpf_program *prog, char *log_buf, size_t log } static int attach_kprobe(const struct bpf_program *prog, long cookie, struct bpf_link **link); +static int attach_uprobe(const struct bpf_program *prog, long cookie, struct bpf_link **link); 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); @@ -8642,9 +8643,9 @@ static const struct bpf_sec_def section_defs[] = { SEC_DEF("sk_reuseport/migrate", SK_REUSEPORT, BPF_SK_REUSEPORT_SELECT_OR_MIGRATE, SEC_ATTACHABLE | SEC_SLOPPY_PFX), SEC_DEF("sk_reuseport", SK_REUSEPORT, BPF_SK_REUSEPORT_SELECT, SEC_ATTACHABLE | SEC_SLOPPY_PFX), SEC_DEF("kprobe/", KPROBE, 0, SEC_NONE, attach_kprobe), - SEC_DEF("uprobe/", KPROBE, 0, SEC_NONE), + SEC_DEF("uprobe+", KPROBE, 0, SEC_NONE, attach_uprobe), SEC_DEF("kretprobe/", KPROBE, 0, SEC_NONE, attach_kprobe), - SEC_DEF("uretprobe/", KPROBE, 0, SEC_NONE), + SEC_DEF("uretprobe+", KPROBE, 0, SEC_NONE, attach_uprobe), 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), @@ -10845,6 +10846,75 @@ err_out: } +/* Format of u[ret]probe section definition supporting auto-attach: + * u[ret]probe/binary:function[+offset] + * + * binary can be an absolute/relative path or a filename; the latter is resolved to a + * full binary path via bpf_program__attach_uprobe_opts. + * + * Specifying uprobe+ ensures we carry out strict matching; either "uprobe" must be + * specified (and auto-attach is not possible) or the above format is specified for + * auto-attach. + */ +static int attach_uprobe(const struct bpf_program *prog, long cookie, struct bpf_link **link) +{ + DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts); + char *func, *probe_name, *func_end; + char *func_name, binary_path[512]; + unsigned long long raw_offset; + size_t offset = 0; + int n; + + *link = NULL; + + opts.retprobe = str_has_pfx(prog->sec_name, "uretprobe"); + if (opts.retprobe) + probe_name = prog->sec_name + sizeof("uretprobe") - 1; + else + probe_name = prog->sec_name + sizeof("uprobe") - 1; + if (probe_name[0] == '/') + probe_name++; + + /* handle SEC("u[ret]probe") - format is valid, but auto-attach is impossible. */ + if (strlen(probe_name) == 0) + return 0; + + snprintf(binary_path, sizeof(binary_path), "%s", probe_name); + /* ':' should be prior to function+offset */ + func_name = strrchr(binary_path, ':'); + if (!func_name) { + pr_warn("section '%s' missing ':function[+offset]' specification\n", + prog->sec_name); + return -EINVAL; + } + func_name[0] = '\0'; + func_name++; + n = sscanf(func_name, "%m[a-zA-Z0-9_.]+%li", &func, &offset); + if (n < 1) { + pr_warn("uprobe name '%s' is invalid\n", func_name); + return -EINVAL; + } + if (opts.retprobe && offset != 0) { + free(func); + pr_warn("uretprobes do not support offset specification\n"); + return -EINVAL; + } + + /* Is func a raw address? */ + errno = 0; + raw_offset = strtoull(func, &func_end, 0); + if (!errno && !*func_end) { + free(func); + func = NULL; + offset = (size_t)raw_offset; + } + opts.func_name = func; + + *link = bpf_program__attach_uprobe_opts(prog, -1, binary_path, offset, &opts); + free(func); + return libbpf_get_error(*link); +} + struct bpf_link *bpf_program__attach_uprobe(const struct bpf_program *prog, bool retprobe, pid_t pid, const char *binary_path, diff --git a/tools/testing/selftests/bpf/progs/test_bpf_cookie.c b/tools/testing/selftests/bpf/progs/test_bpf_cookie.c index 2d3a7710e2ce..0e2222968918 100644 --- a/tools/testing/selftests/bpf/progs/test_bpf_cookie.c +++ b/tools/testing/selftests/bpf/progs/test_bpf_cookie.c @@ -37,14 +37,14 @@ int handle_kretprobe(struct pt_regs *ctx) return 0; } -SEC("uprobe/trigger_func") +SEC("uprobe") int handle_uprobe(struct pt_regs *ctx) { update(ctx, &uprobe_res); return 0; } -SEC("uretprobe/trigger_func") +SEC("uretprobe") int handle_uretprobe(struct pt_regs *ctx) { update(ctx, &uretprobe_res); diff --git a/tools/testing/selftests/bpf/progs/test_task_pt_regs.c b/tools/testing/selftests/bpf/progs/test_task_pt_regs.c index e6cb09259408..1926facba122 100644 --- a/tools/testing/selftests/bpf/progs/test_task_pt_regs.c +++ b/tools/testing/selftests/bpf/progs/test_task_pt_regs.c @@ -14,7 +14,7 @@ char current_regs[PT_REGS_SIZE] = {}; char ctx_regs[PT_REGS_SIZE] = {}; int uprobe_res = 0; -SEC("uprobe/trigger_func") +SEC("uprobe") int handle_uprobe(struct pt_regs *ctx) { struct task_struct *current; diff --git a/tools/testing/selftests/bpf/progs/trigger_bench.c b/tools/testing/selftests/bpf/progs/trigger_bench.c index 2ab049b54d6c..694e7cec1823 100644 --- a/tools/testing/selftests/bpf/progs/trigger_bench.c +++ b/tools/testing/selftests/bpf/progs/trigger_bench.c @@ -54,7 +54,7 @@ int bench_trigger_fmodret(void *ctx) return -22; } -SEC("uprobe/self/uprobe_target") +SEC("uprobe") int bench_trigger_uprobe(void *ctx) { __sync_add_and_fetch(&hits, 1);