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 3A1D11D301 for ; Tue, 25 Jul 2023 11:03:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AEE60C433C7; Tue, 25 Jul 2023 11:02:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1690282980; bh=qdXlhvebIi2jX4eTPe3/M2pIAg4dku76+3qKD0GDnIE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XtOZaW2I9nz8CAjXOUNNg0+C9abXR447QTAsxiURyc3S7iMfipstCfxqUVQ4ks8ZA jBNTDPqYBk6vqXdXqcHhGhmAUvWIrFxSMpKKfO8dt7DfxejaaO2HZotTXGLpDp85KI SWowRycSLtTIt2DzWXs3dBSAKUcpkRJVzmTcQM98= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Kui-Feng Lee , Andrii Nakryiko , Yonghong Song , Sasha Levin Subject: [PATCH 6.1 067/183] bpf: Print a warning only if writing to unprivileged_bpf_disabled. Date: Tue, 25 Jul 2023 12:44:55 +0200 Message-ID: <20230725104510.376159921@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230725104507.756981058@linuxfoundation.org> References: <20230725104507.756981058@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Kui-Feng Lee [ Upstream commit fedf99200ab086c42a572fca1d7266b06cdc3e3f ] Only print the warning message if you are writing to "/proc/sys/kernel/unprivileged_bpf_disabled". The kernel may print an annoying warning when you read "/proc/sys/kernel/unprivileged_bpf_disabled" saying WARNING: Unprivileged eBPF is enabled with eIBRS on, data leaks possible via Spectre v2 BHB attacks! However, this message is only meaningful when the feature is disabled or enabled. Signed-off-by: Kui-Feng Lee Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20230502181418.308479-1-kuifeng@meta.com Signed-off-by: Sasha Levin --- kernel/bpf/syscall.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 8633ec4f92df3..0c44a716f0a24 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -5289,7 +5289,8 @@ static int bpf_unpriv_handler(struct ctl_table *table, int write, *(int *)table->data = unpriv_enable; } - unpriv_ebpf_notify(unpriv_enable); + if (write) + unpriv_ebpf_notify(unpriv_enable); return ret; } -- 2.39.2