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=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 A9096C46475 for ; Thu, 25 Oct 2018 14:15:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 713C720868 for ; Thu, 25 Oct 2018 14:15:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="DMIm+sAD" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 713C720868 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728930AbeJYWsU (ORCPT ); Thu, 25 Oct 2018 18:48:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:56922 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728919AbeJYWsS (ORCPT ); Thu, 25 Oct 2018 18:48:18 -0400 Received: from sasha-vm.mshome.net (unknown [167.98.65.38]) (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 A6C0520854; Thu, 25 Oct 2018 14:15:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1540476922; bh=SbngomlX9o96OXBRAGaak/c/3XUg6WWxxcIvJhG/xnU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DMIm+sADkSTsRA/itSdwEGAHaDL4dRnDx46VTzhJlzIjKSvl0pD2/bb3x2LpAifeE rFxT0Zvg7swLd/ky8Kw8geRMn841aeOtaAux07SaEsPUfTGIaSJUYrptrZBRZDreDh yJcz+n2RvD8OSNP66NhChAkKj/6KKl41WNPagLOc= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Eric Biggers , Jens Axboe , Sasha Levin Subject: [PATCH AUTOSEL 4.9 39/98] elevator: fix truncation of icq_cache_name Date: Thu, 25 Oct 2018 10:13:24 -0400 Message-Id: <20181025141423.213774-39-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181025141423.213774-1-sashal@kernel.org> References: <20181025141423.213774-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Biggers [ Upstream commit 9bd2bbc01d17ddd567cc0f81f77fe1163e497462 ] gcc 7.1 reports the following warning: block/elevator.c: In function ‘elv_register’: block/elevator.c:898:5: warning: ‘snprintf’ output may be truncated before the last format character [-Wformat-truncation=] "%s_io_cq", e->elevator_name); ^~~~~~~~~~ block/elevator.c:897:3: note: ‘snprintf’ output between 7 and 22 bytes into a destination of size 21 snprintf(e->icq_cache_name, sizeof(e->icq_cache_name), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "%s_io_cq", e->elevator_name); ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The bug is that the name of the icq_cache is 6 characters longer than the elevator name, but only ELV_NAME_MAX + 5 characters were reserved for it --- so in the case of a maximum-length elevator name, the 'q' character in "_io_cq" would be truncated by snprintf(). Fix it by reserving ELV_NAME_MAX + 6 characters instead. Signed-off-by: Eric Biggers Reviewed-by: Bart Van Assche Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- include/linux/elevator.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/elevator.h b/include/linux/elevator.h index e7f358d2e5fc..eaa58c0f894b 100644 --- a/include/linux/elevator.h +++ b/include/linux/elevator.h @@ -102,7 +102,7 @@ struct elevator_type struct module *elevator_owner; /* managed by elevator core */ - char icq_cache_name[ELV_NAME_MAX + 5]; /* elvname + "_io_cq" */ + char icq_cache_name[ELV_NAME_MAX + 6]; /* elvname + "_io_cq" */ struct list_head list; }; -- 2.17.1