From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Stancek Date: Fri, 30 Oct 2015 05:29:01 -0400 (EDT) Subject: [LTP] [PATCH 6/11] mmap/mmap12: Testcase failed when no root user run it In-Reply-To: <563330C4.2060809@huawei.com> References: <1446001907-43525-1-git-send-email-cuibixuan@huawei.com> <1446001907-43525-6-git-send-email-cuibixuan@huawei.com> <20151029115746.GA23990@rei> <563330C4.2060809@huawei.com> Message-ID: <492224674.39010592.1446197341093.JavaMail.zimbra@redhat.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it ----- Original Message ----- > From: "Cui Bixuan" > To: "Cyril Hrubis" > Cc: zhuyanpeng@huawei.com, zhanyongming@huawei.com, ltp@lists.linux.it > Sent: Friday, 30 October, 2015 9:56:36 AM > Subject: Re: [LTP] [PATCH 6/11] mmap/mmap12: Testcase failed when no root user run it > > On 2015/10/29 19:57, Cyril Hrubis wrote: > > Hi! > >> Add tst_require_root() to testcase for open /proc/self/pagemap file. > > > > On my machines the /proc/self/pagemap is readable by the process (it's > > owned by the user that has started the program). > > > > What is output of ls -l /proc/self/pagemap on your machine? > I look my system and others: > 1) SUSE SP2: 3.0.13-0.27-default (uname -a); test PASS; -r--r--r-- 1 root > root 0 Oct 30 16:13 /proc/self/pagemap > 2) Ubuntu: 3.13.0-32-generic; test PASS; -r--r--r--. 1 > cuibixuan cuibixuan 0 10? 30 16:19 /proc/self/pagemap > 3) SUSE: 4.2.0-0.11-default; test FAIL; -r-------- 1 root > root 0 Nov 13 01:39 /proc/self/pagemap > 4) arm64: linux 4.1.6; test FAIL; -r-------- 1 root > root 0 Jan 18 01:53 /proc/self/pagemap > > Maybe the higher version of the kernel change the file attributes > of /proc/self/pagemap, I think. commit 32ed74a4b968a4faff7aaaff557035ce5d5e70ab Author: Djalal Harouni Date: Mon Apr 7 15:38:38 2014 -0700 procfs: make /proc/*/pagemap 0400 The /proc/*/pagemap contain sensitive information and currently its mode is 0444. Change this to 0400, so the VFS will prevent unprivileged processes from getting file descriptors on arbitrary privileged /proc/*/pagemap files. but that doesn't explain why process can't read its own pagemap. For 3) and 4): Did you run that as unprivileged user or as a root? Can you paste full output from mmap12 run (the one that fails)? Regards, Jan > > But I read the Documentation/vm/pagemap.txt and look at the source code in > kernel, > can't get it. :-( > > Someone help? > > > > > -- > Mailing list info: http://lists.linux.it/listinfo/ltp >