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[173.68.184.64]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-47e9f7a820esm17673281cf.41.2025.04.24.15.15.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 24 Apr 2025 15:15:00 -0700 (PDT) From: ">" X-Google-Original-From: Jonathan Wiepert jonathan.wiepert@gmail.com> To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Mykyta Yatsenko , Yonghong Song , Jordan Rome , Jiri Olsa , Jonathan Wiepert , Kernel Team Subject: [PATCH bpf-next] Use thread-safe function pointer in libbpf_print Date: Thu, 24 Apr 2025 18:14:57 -0400 Message-ID: <20250424221457.793068-1-jonathan.wiepert@gmail.com> X-Mailer: git-send-email 2.42.0 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Jonathan Wiepert This patch fixes a thread safety bug where libbpf_print uses the global variable storing the print function pointer rather than the local variable that had the print function set via __atomic_load_n. Signed-off-by: Jonathan Wiepert --- tools/lib/bpf/libbpf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 56250b5ac5b0..ea97a84460cd 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -284,7 +284,7 @@ void libbpf_print(enum libbpf_print_level level, const char *format, ...) old_errno = errno; va_start(args, format); - __libbpf_pr(level, format, args); + print_fn(level, format, args); va_end(args); errno = old_errno; -- 2.42.0