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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 849A9C433F5 for ; Fri, 31 Dec 2021 17:09:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230323AbhLaRJG (ORCPT ); Fri, 31 Dec 2021 12:09:06 -0500 Received: from mga12.intel.com ([192.55.52.136]:5867 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229699AbhLaRJE (ORCPT ); Fri, 31 Dec 2021 12:09:04 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1640970544; x=1672506544; h=date:from:to:cc:subject:message-id:mime-version; bh=mDXZTBMOVLtUoZSEauTALat78Hj4BDtqet/RojZ9xSc=; b=RIOoI2f2ftqgLIR+77t6EMQfuppY9JWtFe8eVuiLORgzzmLAKG++XpNb ydz0KFxPUAQUq6Ds3He1xV+MX2qCAyQm1QjUxCyw+8RUMYpeZc7NbgSq2 3OTiG3lj9T/6XLtdDQlDjQXlHOBF9jQ3RzEQuApi2fObVMsADIuq6+fMf usrW7F6PTktBG51JWz0weZwGBtVTrC87gH+ElODRDver+acwQEDoZ4qzd AeIJ6CjuBPnfIZJ6h1enx4hM1W6WEPG5LqqyjuVVpWln/TC8dVT+ump34 wzcGu4bUpO1V8ZNiLBXzEgoKvyxXLL9z3KNLSwDHYSVrLY8ae9zF6WgOP w==; X-IronPort-AV: E=McAfee;i="6200,9189,10213"; a="221825323" X-IronPort-AV: E=Sophos;i="5.88,252,1635231600"; d="scan'208";a="221825323" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Dec 2021 09:09:04 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,252,1635231600"; d="scan'208";a="619676116" Received: from lkp-server01.sh.intel.com (HELO e357b3ef1427) ([10.239.97.150]) by orsmga004.jf.intel.com with ESMTP; 31 Dec 2021 09:09:03 -0800 Received: from kbuild by e357b3ef1427 with local (Exim 4.92) (envelope-from ) id 1n3LOo-000BR3-EB; Fri, 31 Dec 2021 17:09:02 +0000 Date: Sat, 1 Jan 2022 01:08:41 +0800 From: kernel test robot To: Greg Kroah-Hartman Cc: kbuild-all@lists.01.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Subject: [driver-core:debugfs_cleanup 4/5] fs/d_path.c:59 prepend() warn: unsigned 'p->len' is never less than zero. Message-ID: <202201010156.bJvO7Gaw-lkp@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git debugfs_cleanup head: a04bbe0a2c7e98669e11a47f94e53dd8228bbeba commit: e95d5bed5d58c2f5352969369827e7135fa2261e [4/5] fs: make d_path-like functions all have unsigned size config: i386-randconfig-m031-20211228 (https://download.01.org/0day-ci/archive/20220101/202201010156.bJvO7Gaw-lkp@intel.com/config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot smatch warnings: fs/d_path.c:59 prepend() warn: unsigned 'p->len' is never less than zero. vim +59 fs/d_path.c b0cfcdd9b9672e Linus Torvalds 2021-07-16 55 b0cfcdd9b9672e Linus Torvalds 2021-07-16 56 static bool prepend(struct prepend_buffer *p, const char *str, int namelen) b0cfcdd9b9672e Linus Torvalds 2021-07-16 57 { b0cfcdd9b9672e Linus Torvalds 2021-07-16 58 // Already overflowed? b0cfcdd9b9672e Linus Torvalds 2021-07-16 @59 if (p->len < 0) b0cfcdd9b9672e Linus Torvalds 2021-07-16 60 return false; b0cfcdd9b9672e Linus Torvalds 2021-07-16 61 b0cfcdd9b9672e Linus Torvalds 2021-07-16 62 // Will overflow? b0cfcdd9b9672e Linus Torvalds 2021-07-16 63 if (p->len < namelen) { b0cfcdd9b9672e Linus Torvalds 2021-07-16 64 // Fill as much as possible from the end of the name b0cfcdd9b9672e Linus Torvalds 2021-07-16 65 str += namelen - p->len; b0cfcdd9b9672e Linus Torvalds 2021-07-16 66 p->buf -= p->len; b0cfcdd9b9672e Linus Torvalds 2021-07-16 67 prepend_copy(p->buf, str, p->len); b0cfcdd9b9672e Linus Torvalds 2021-07-16 68 p->len = -1; b0cfcdd9b9672e Linus Torvalds 2021-07-16 69 return false; b0cfcdd9b9672e Linus Torvalds 2021-07-16 70 } b0cfcdd9b9672e Linus Torvalds 2021-07-16 71 b0cfcdd9b9672e Linus Torvalds 2021-07-16 72 // Fits fully ad08ae586586ea Al Viro 2021-05-12 73 p->len -= namelen; ad08ae586586ea Al Viro 2021-05-12 74 p->buf -= namelen; b0cfcdd9b9672e Linus Torvalds 2021-07-16 75 return prepend_copy(p->buf, str, namelen); 7a5cf791a74764 Al Viro 2018-03-05 76 } 7a5cf791a74764 Al Viro 2018-03-05 77 :::::: The code at line 59 was first introduced by commit :::::: b0cfcdd9b9672ea90642f33d6c0dd8516553adf2 d_path: make 'prepend()' fill up the buffer exactly on overflow :::::: TO: Linus Torvalds :::::: CC: Linus Torvalds --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org