From patchwork Sat Aug 12 12:05:10 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Phil Sutter X-Patchwork-Id: 800858 X-Patchwork-Delegate: shemminger@vyatta.com Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3xV0vZ5WvKz9t3C for ; Sat, 12 Aug 2017 22:06:02 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752326AbdHLMFu (ORCPT ); Sat, 12 Aug 2017 08:05:50 -0400 Received: from orbyte.nwl.cc ([151.80.46.58]:34941 "EHLO mail.nwl.cc" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752138AbdHLMFs (ORCPT ); Sat, 12 Aug 2017 08:05:48 -0400 Received: from mail.nwl.cc (orbyte.nwl.cc [127.0.0.1]) by mail.nwl.cc (Postfix) with ESMTP id 7A94368252; Sat, 12 Aug 2017 14:05:47 +0200 (CEST) Received: from xsao (localhost [IPv6:::1]) by mail.nwl.cc (Postfix) with ESMTP id 5DC2F681D7; Sat, 12 Aug 2017 14:05:47 +0200 (CEST) From: Phil Sutter To: Stephen Hemminger Cc: netdev@vger.kernel.org Subject: [iproute PATCH 51/51] lib/bpf: Check return value of write() Date: Sat, 12 Aug 2017 14:05:10 +0200 Message-Id: <20170812120510.28750-52-phil@nwl.cc> X-Mailer: git-send-email 2.13.1 In-Reply-To: <20170812120510.28750-1-phil@nwl.cc> References: <20170812120510.28750-1-phil@nwl.cc> X-Virus-Scanned: ClamAV using ClamSMTP Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This is merely to silence the compiler warning. If write to stderr failed, assume that printing an error message will fail as well so don't even try. Signed-off-by: Phil Sutter Acked-by: Daniel Borkmann --- lib/bpf.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/lib/bpf.c b/lib/bpf.c index 1dcb261dc915f..825e071cea572 100644 --- a/lib/bpf.c +++ b/lib/bpf.c @@ -591,7 +591,8 @@ int bpf_trace_pipe(void) ret = read(fd, buff, sizeof(buff) - 1); if (ret > 0) { - write(2, buff, ret); + if (write(STDERR_FILENO, buff, ret) != ret) + return -1; fflush(stderr); } }