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* [PATCH bpf-next 1/2] libbpf: fix memory leak in legacy kprobe attach logic
@ 2021-09-20 18:19 Andrii Nakryiko
  2021-09-20 18:19 ` [PATCH bpf-next 2/2] libbpf: fix legacy kprobe event creation FD error handling Andrii Nakryiko
  0 siblings, 1 reply; 3+ messages in thread
From: Andrii Nakryiko @ 2021-09-20 18:19 UTC (permalink / raw)
  To: bpf, ast, daniel; +Cc: andrii, kernel-team

In some error scenarios legacy_probe string won't be free()'d. Fix this.
This was reported by Coverity static analysis.

Fixes: ca304b40c20d ("libbpf: Introduce legacy kprobe events support")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
 tools/lib/bpf/libbpf.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index da65a1666a5e..6d2f12db6034 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -9365,10 +9365,11 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
 						    offset, -1 /* pid */);
 	}
 	if (pfd < 0) {
+		err = pfd;
 		pr_warn("prog '%s': failed to create %s '%s' perf event: %s\n",
 			prog->name, retprobe ? "kretprobe" : "kprobe", func_name,
-			libbpf_strerror_r(pfd, errmsg, sizeof(errmsg)));
-		return libbpf_err_ptr(pfd);
+			libbpf_strerror_r(err, errmsg, sizeof(errmsg)));
+		goto err_out;
 	}
 	link = bpf_program__attach_perf_event_opts(prog, pfd, &pe_opts);
 	err = libbpf_get_error(link);
@@ -9377,7 +9378,7 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
 		pr_warn("prog '%s': failed to attach to %s '%s': %s\n",
 			prog->name, retprobe ? "kretprobe" : "kprobe", func_name,
 			libbpf_strerror_r(err, errmsg, sizeof(errmsg)));
-		return libbpf_err_ptr(err);
+		goto err_out;
 	}
 	if (legacy) {
 		struct bpf_link_perf *perf_link = container_of(link, struct bpf_link_perf, link);
@@ -9387,6 +9388,9 @@ bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
 	}
 
 	return link;
+err_out:
+	free(legacy_probe);
+	return libbpf_err_ptr(err);
 }
 
 struct bpf_link *bpf_program__attach_kprobe(const struct bpf_program *prog,
-- 
2.30.2


^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2021-09-21  1:59 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2021-09-20 18:19 [PATCH bpf-next 1/2] libbpf: fix memory leak in legacy kprobe attach logic Andrii Nakryiko
2021-09-20 18:19 ` [PATCH bpf-next 2/2] libbpf: fix legacy kprobe event creation FD error handling Andrii Nakryiko
2021-09-20 23:23   ` Andrii Nakryiko

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