From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8CF21C48BD9 for ; Thu, 27 Jun 2019 00:31:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 643C0217F9 for ; Thu, 27 Jun 2019 00:31:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561595462; bh=EoVevRrncZLwzRFqE1UttWd6FrNKzV+ovzUOIn7khe8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Fb/EoP9xu2dgUjFs0F0kcjgL0ijAfgcoik2ttIk2MGwIg/Wd6MDcprNen4b6Y0R6g 7LZyEF2ho1Why7H8txfIpNvktjR2qCtpTM3HM9tX++AwndbhLnZijv4riVJM0Q9ttW wWMqeDsFyzEnQOcgCDWTV+efLgwftXcYNyD4yz3A= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726981AbfF0Aa7 (ORCPT ); Wed, 26 Jun 2019 20:30:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:34164 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726956AbfF0Aay (ORCPT ); Wed, 26 Jun 2019 20:30:54 -0400 Received: from sasha-vm.mshome.net (unknown [107.242.116.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A9F602083B; Thu, 27 Jun 2019 00:30:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561595454; bh=EoVevRrncZLwzRFqE1UttWd6FrNKzV+ovzUOIn7khe8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GjUPdg8XmdOhHZu7grKIjVpIPnqvA271FbHIfFfqB9oafi2rUfsUD4icMxMCXjrrr iaCMSdoztvIHD7sVN692kYC2P6c8aT5ADkxiBvBL2GE4BdeRXU3sSEJksgfrqJv8En PWwWnzCx7faxovz/++9E8Y/pRD+tMOdfOYLUlWY0= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Matteo Croce , Daniel Borkmann , Sasha Levin , netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 5.1 10/95] samples, bpf: suppress compiler warning Date: Wed, 26 Jun 2019 20:28:55 -0400 Message-Id: <20190627003021.19867-10-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190627003021.19867-1-sashal@kernel.org> References: <20190627003021.19867-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Matteo Croce [ Upstream commit a195cefff49f60054998333e81ee95170ce8bf92 ] GCC 9 fails to calculate the size of local constant strings and produces a false positive: samples/bpf/task_fd_query_user.c: In function ‘test_debug_fs_uprobe’: samples/bpf/task_fd_query_user.c:242:67: warning: ‘%s’ directive output may be truncated writing up to 255 bytes into a region of size 215 [-Wformat-truncation=] 242 | snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/%ss/%s/id", | ^~ 243 | event_type, event_alias); | ~~~~~~~~~~~ samples/bpf/task_fd_query_user.c:242:2: note: ‘snprintf’ output between 45 and 300 bytes into a destination of size 256 242 | snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/%ss/%s/id", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 243 | event_type, event_alias); | ~~~~~~~~~~~~~~~~~~~~~~~~ Workaround this by lowering the buffer size to a reasonable value. Related GCC Bugzilla: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83431 Signed-off-by: Matteo Croce Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin --- samples/bpf/task_fd_query_user.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/samples/bpf/task_fd_query_user.c b/samples/bpf/task_fd_query_user.c index aff2b4ae914e..e39938058223 100644 --- a/samples/bpf/task_fd_query_user.c +++ b/samples/bpf/task_fd_query_user.c @@ -216,7 +216,7 @@ static int test_debug_fs_uprobe(char *binary_path, long offset, bool is_return) { const char *event_type = "uprobe"; struct perf_event_attr attr = {}; - char buf[256], event_alias[256]; + char buf[256], event_alias[sizeof("test_1234567890")]; __u64 probe_offset, probe_addr; __u32 len, prog_id, fd_type; int err, res, kfd, efd; -- 2.20.1