Currently, libbpf requires specifying binary path when attach USDT BPF program
manually. This is not necessary because we can infer that from /proc/$PID/exe.
This also avoids coredump when user do not provide binary path.
Signed-off-by: Hengqi Chen <hengqi.chen@xxxxxxxxx>
---
tools/lib/bpf/libbpf.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 8a45a84eb9b2..4ee9b6a0944e 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -10686,7 +10686,19 @@ struct bpf_link *bpf_program__attach_usdt(const struct bpf_program *prog,
return libbpf_err_ptr(-EINVAL);
}
- if (!strchr(binary_path, '/')) {
+ if (!binary_path) {
+ if (pid < 0) {
+ pr_warn("prog '%s': missing attach target, pid or binary path required\n",
+ prog->name);
+ return libbpf_err_ptr(-EINVAL);
+ }
+ if (!pid)
+ binary_path = "/proc/self/exe";
+ else {
+ snprintf(resolved_path, sizeof(resolved_path), "/proc/%d/exe", pid);
+ binary_path = resolved_path;
+ }
+ } else if (!strchr(binary_path, '/')) {
err = resolve_full_path(binary_path, resolved_path, sizeof(resolved_path));
if (err) {
pr_warn("prog '%s': failed to resolve full path for '%s': %d\n",
--
2.30.2
