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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 3B27AC32750 for ; Fri, 2 Aug 2019 09:39:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 10E4920679 for ; Fri, 2 Aug 2019 09:39:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564738763; bh=TmMe6w4uJikcmWxDy9aha4me4xYkKfIJtTY9M5JoQRE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=XFSZbf5FnhBjNHIKF8RZD5jjDxqQoHucpcj/WAe1VASgBQgQUOp/PfmcugjxzPLb0 HnXPn+DWrVsnzCLrrklN09CufL9alI6Tku5nOksuORYsnyr6i7qgtY38iT48gkinG/ P2IxfApwsBUcGWiUdJFMftqDgxwSw5b4AfdW6fLY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391378AbfHBJdt (ORCPT ); Fri, 2 Aug 2019 05:33:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:33368 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391425AbfHBJdt (ORCPT ); Fri, 2 Aug 2019 05:33:49 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C132A21773; Fri, 2 Aug 2019 09:33:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564738428; bh=TmMe6w4uJikcmWxDy9aha4me4xYkKfIJtTY9M5JoQRE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HmGWduCfpuNb5De1hWaINbPTEwhljVXRc2/pj4c6LEHAgiFf1wbUMdLI/i9T90wSR Qm4vs1cNFC5NFKFBj75cmkGj6aQtSHBhUDVub3Ryka2+lpDLuwMatXnmwynqeLsFEy KEtNxtWYc0HsVKp3oNaE4fh4u/jh7Y37ydL0IgWI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Biggers , Bart Van Assche , Jens Axboe Subject: [PATCH 4.4 100/158] elevator: fix truncation of icq_cache_name Date: Fri, 2 Aug 2019 11:28:41 +0200 Message-Id: <20190802092224.860632666@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190802092203.671944552@linuxfoundation.org> References: <20190802092203.671944552@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Biggers commit 9bd2bbc01d17ddd567cc0f81f77fe1163e497462 upstream. 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: Greg Kroah-Hartman --- include/linux/elevator.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/include/linux/elevator.h +++ b/include/linux/elevator.h @@ -97,7 +97,7 @@ 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; };