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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 48C82C433DF for ; Wed, 20 May 2020 01:48:50 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0C5C6207D8 for ; Wed, 20 May 2020 01:48:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="nwLV5Rqw" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0C5C6207D8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A30428003D; Tue, 19 May 2020 21:48:49 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9DE918002C; Tue, 19 May 2020 21:48:49 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8F3C08003D; Tue, 19 May 2020 21:48:49 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0093.hostedemail.com [216.40.44.93]) by kanga.kvack.org (Postfix) with ESMTP id 742578002C for ; Tue, 19 May 2020 21:48:49 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 2D4CD180AD815 for ; Wed, 20 May 2020 01:48:49 +0000 (UTC) X-FDA: 76835413578.25.sock59_2fdb6dfe9ca39 X-HE-Tag: sock59_2fdb6dfe9ca39 X-Filterd-Recvd-Size: 3271 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf33.hostedemail.com (Postfix) with ESMTP for ; Wed, 20 May 2020 01:48:48 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (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 B589C2075F; Wed, 20 May 2020 01:48:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589939328; bh=5b3m5wFU4hh9Yv7TMddahce+qOkkHM0MuT6Fti2iXIs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=nwLV5Rqwvc8jicA632QYsFEE2NijiwSig33QJZW92YQP8EcAPtyVF8Nk31RJv0D4m aDxKLuYLlmmJlg2PyRbB1Bz8ob+JRDhdtkDFETlLS9WHESNn+bT6ID+DRDzrsw65E2 4t9jJKjfV6ZA/8Qq8kdBFTpBGZFkSTeKpXnYxBgs= Date: Tue, 19 May 2020 18:48:47 -0700 From: Andrew Morton To: Daniel Axtens Cc: kbuild test robot , kbuild-all@lists.01.org, Johannes Weiner , Dmitry Vyukov , Linux Memory Management List , linux-scsi@vger.kernel.org Subject: Re: [hnaz-linux-mm:master 156/523] include/linux/string.h:307:9: note: in expansion of macro '__underlying_strncpy' Message-Id: <20200519184847.5affb9238b7358ac0d18c98e@linux-foundation.org> In-Reply-To: <87blmkhtpy.fsf@dja-thinkpad.axtens.net> References: <202005191736.t1JQZSrV%lkp@intel.com> <87blmkhtpy.fsf@dja-thinkpad.axtens.net> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 20 May 2020 00:42:17 +1000 Daniel Axtens wrote: > This looks like a SCSI issue that this has just happened to expose? > + scsi list Maybe. static void arcmsr_handle_virtual_command(struct AdapterControlBlock *acb, struct scsi_cmnd *cmd) { switch (cmd->cmnd[0]) { case INQUIRY: { unsigned char inqdata[36]; char *buffer; struct scatterlist *sg; if (cmd->device->lun) { cmd->result = (DID_TIME_OUT << 16); cmd->scsi_done(cmd); return; } inqdata[0] = TYPE_PROCESSOR; /* Periph Qualifier & Periph Dev Type */ inqdata[1] = 0; /* rem media bit & Dev Type Modifier */ inqdata[2] = 0; /* ISO, ECMA, & ANSI versions */ inqdata[4] = 31; /* length of additional data */ strncpy(&inqdata[8], "Areca ", 8); /* Vendor Identification */ >>> strncpy(&inqdata[16], "RAID controller ", 16); /* Product Identification */ strncpy(&inqdata[32], "R001", 4); /* Product Revision */ sg = scsi_sglist(cmd); buffer = kmap_atomic(sg_page(sg)) + sg->offset; memcpy(buffer, inqdata, sizeof(inqdata)); sg = scsi_sglist(cmd); kunmap_atomic(buffer - sg->offset); cmd->scsi_done(cmd); } break; That strncpy() will indeed fail to copy the trailing null, but it looks like that null isn't appropriate in the inquiry data. So I suspect this is a valid usage of strncpy() and the checking is just too strict. otoh if this is the only place where we hit this issue then perhaps we can switch to memcpy() and get on with life ;)