From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6487D2DF3C9; Tue, 17 Jun 2025 15:37:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750174656; cv=none; b=F1KjtV3pe7z3ONNxAp1OO7/PFvZncrU8bGYQo6opcbl6CbxZaydlZE/8AHdjcKFmaKeKYn5x3fuZoUJhQgDvY73dTkwo1p4sW6Vs+udHkzKOsUUVe0nYjy7UoAW83mup20ai+UOkWISW+07AanFI1alopULyiW2DCCDDPzgcW7Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750174656; c=relaxed/simple; bh=JypuzBis73hv2S0zz4bsC4aywDqJOnJUn41Jn552veo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Igf7WlM0xmSRvxLiqJtUoupSbs8HNecGmkirVXP18Iua5mSDJ3pWiObXcBO0qQ+f7QOaDgh/THiC1OElprdpFagHZYEvBP2U1TcrowojryJHDex2KAORH8aknioXQAJTbJcs5svIAZ0gL8Bfk58DLWHP+PkPQY2UWOGMpXlxCeE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=erItK4tJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="erItK4tJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9E69C4CEF0; Tue, 17 Jun 2025 15:37:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750174656; bh=JypuzBis73hv2S0zz4bsC4aywDqJOnJUn41Jn552veo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=erItK4tJJspralb6SGsNSMdH/6NLjukmr4jG2jLcARWWb+WlnFBRsaDO5jQ8Lu8e/ 2IdRzSGHOfNJXvstZ6ODxmQs3GzG1oX7hiji7GrIHvdq2TIJUuCLIXSLsY9T8wvwtr mdQzSiv48HbjTeFJ9HYXGQ6WQHlQGRJUFpmqDYSs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jonathan Wiepert , Andrii Nakryiko , Mykyta Yatsenko , Sasha Levin Subject: [PATCH 6.6 099/356] Use thread-safe function pointer in libbpf_print Date: Tue, 17 Jun 2025 17:23:34 +0200 Message-ID: <20250617152342.210098182@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250617152338.212798615@linuxfoundation.org> References: <20250617152338.212798615@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jonathan Wiepert [ Upstream commit 91dbac4076537b464639953c055c460d2bdfc7ea ] 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. Fixes: f1cb927cdb62 ("libbpf: Ensure print callback usage is thread-safe") Signed-off-by: Jonathan Wiepert Signed-off-by: Andrii Nakryiko Acked-by: Mykyta Yatsenko Link: https://lore.kernel.org/bpf/20250424221457.793068-1-jonathan.wiepert@gmail.com Signed-off-by: Sasha Levin --- 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 18e96375dc319..5dc2e55553358 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -246,7 +246,7 @@ 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; -- 2.39.5