From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752100AbeBUSoR (ORCPT ); Wed, 21 Feb 2018 13:44:17 -0500 Received: from mail-wr0-f171.google.com ([209.85.128.171]:41630 "EHLO mail-wr0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751610AbeBUSoP (ORCPT ); Wed, 21 Feb 2018 13:44:15 -0500 X-Google-Smtp-Source: AH8x226lJLt0+eS/0Fc0LU3mOgraRtg7XE0K8Izj9V0qPsqiRMY7KtXcvDvsaI5+N5PeiogLyKUQ4A== Date: Wed, 21 Feb 2018 21:44:11 +0300 From: Alexey Dobriyan To: akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, avagin@virtuozzo.com Subject: [PATCH] proc: fix /proc/*/map_files lookup some more Message-ID: <20180221184411.GA25924@avx2> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.7.2 (2016-11-26) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I totally forgot that _parse_integer() accepts arbitrary amount of leading zeroes leading to the following: OK # readlink /proc/1/map_files/56427ecba000-56427eddc000 /lib/systemd/systemd bogus # readlink /proc/1/map_files/00000000000056427ecba000-56427eddc000 /lib/systemd/systemd # readlink /proc/1/map_files/56427ecba000-00000000000056427eddc000 /lib/systemd/systemd Signed-off-by: Alexey Dobriyan --- fs/proc/base.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1913,9 +1913,11 @@ static int dname_to_vma_addr(struct dentry *dentry, unsigned long *start, unsigned long *end) { const char *str = dentry->d_name.name; + unsigned int len = dentry->d_name.len; unsigned long long sval, eval; - unsigned int len; + if (len > 1 && *str == '0') + return -EINVAL; len = _parse_integer(str, 16, &sval); if (len & KSTRTOX_OVERFLOW) return -EINVAL; @@ -1927,6 +1929,9 @@ static int dname_to_vma_addr(struct dentry *dentry, return -EINVAL; str++; + len = strlen(str); + if (len > 1 && *str == '0') + return -EINVAL; len = _parse_integer(str, 16, &eval); if (len & KSTRTOX_OVERFLOW) return -EINVAL;