chmod is used to change the commonly used read, write, and execute permissions on files. It can change these permission bits for the file owner, the file's group owner, and everyone else. It can also change the more esoteric ‘permissions’ (attributes, reall) like set-user-ID, set-group-ID, and ...

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1k views

How to hide someone else's directories from a user?

I have several folders: /home/user1/ -u user1 -G user1 /home/user2/ -u user2 -G user2 /home/user3/ -u user3 -G user3 I created three users user1, user2, user3. Each user has their own group. Any ...
0
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1answer
27 views

ACL contradict chmod

I have installed opencart 1.5.6.1 on Digital ocean ubuntu14.04 I have used "demo" as username and login by tightvnc opencart requird "www-data" as owner and group: $ sudo chown -R www-data:www-data ...
2
votes
1answer
30 views

What is the meaning of the mode mask names from stat(2) and chmod(2)?

The stat calls have a series of symbolic names for the various bits in the mode field. From the stat(2) manual page: The following mask values are defined for the file mode component of the st_mode ...
0
votes
2answers
74 views

chmod – execute permission for non-admins?

I have used chmod to make all the contents of a directory executable. However, when I try to run one of the programs in that directory as a regular user (me), I get a "command not found" message. If ...
1
vote
2answers
34 views

shell script for chmod file name but only on new files since last run of the script

i have a directory where new files are uploaded and receive numeric filename as they are uploaded. the file name is numbers that go up. i need to change permissions for the file but only on new files ...
121
votes
8answers
13k views

How to chmod without /usr/bin/chmod?

Today I was told a tale by a Unix trainer, a tale where the root password got leaked to the students, and one of the fellas removed the execute permission from /usr/bin/chmod itself. How do you ...
0
votes
0answers
22 views

Prevent other user read my files

Hello i have 2 users Joe is root and Gary (normal user) but if gary enter 'cat /home/joe/function.php' gary can view all code with mysql password into this file. What is the solution for disable all ...
2
votes
1answer
49 views

Give permissions to change permissions

I am running a script to deploy a website on a server. It gives me the following error: DEBUG [4223cc8a] Command: /usr/bin/env chmod +x /tmp/mysite_staging/git-ssh.sh DEBUG [4223cc8a] changing ...
2
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4answers
4k views

'chmod g+s' command

Hello I want to understand the role of the chmod g+s command in Unix. I also would like to know what it does in this particular context: cd /home/canard; touch un; chgrp canard .; chmod g+s .; touch ...
2
votes
2answers
72 views

Is it possible to change the directory permission to its previous state?

I have accidentally changed the permission of "/usr/bin" directory and its files by the command: $chmod 775 /usr/bin -R First, there was a problem with sudo but I fixed it. Now I am suspicious that ...
0
votes
1answer
41 views

Always get Error: Operation not supported for: find /Path/ -type f -exec chmod 755 {} \;

I want to change the access permissions for MP3 files on an external 2,5" HDD on my Raspberry Pi on which I run an actual version of Raspian. To do so I tried to use the following command: find ...
1
vote
1answer
35 views

changing file premissions doesn't work

I ssh into a server, and tried changing a files permission. This is what I got: $ ll total 1 -rwx--x--x 1 <user> <groups> 17 Jul 29 12:06 index.html $ chmod 777 index.html $ echo $? 0 $ ...
2
votes
1answer
2k views

Allow all group members to create directories and files

There are 2 users sftp_user apache Both users belong to the updaters group as well as other groups. New directories and files are created in the /updates/ directory. drwxrwsr-x 8 sftp updaters ...
-1
votes
2answers
31 views

How to make an existing directory (and sub-directories) to be suddenly writable by ROOT ONLY?

Let's say i have a directory, at: /tmp/uploads/ And inside got several recursive directories and files created by DIFFERENT USERS before. So now, suddenly how do i make that above directory to be ...
-2
votes
1answer
52 views

How to make a NON-WRITABLE directory?

Actually i'm aware of a "PHP Web Folder". There seems to be some potentials of incoming attacks. So that i want to make sure this whole directory is READ-ONLY (Only writable by ROOT). Let's say the ...
7
votes
8answers
10k views

Convert ls -l output format to chmod format

Say I have the following output from ls -l: drwxr-xr-x 2 root root 4096 Apr 7 17:21 foo How can I automatically convert this to the format used by chmod? For example: $ echo drwxr-xr-x | ...
15
votes
3answers
1k views

Purpose of permissions such as 0111 or 0333

What is the purpose of Linux permissions such as 111 or 333 (i.e. the user can execute, but cannot read the file), if the ability to execute does not automatically imply the ability to read?
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vote
2answers
65 views

How to Change Owner of a Directory

EDIT: The problem was that Apple uses permissions to mark backups and prevents you from modifying them (probably a security feature). By using chmod -RN <dir> I removed ACL data from all the ...
1
vote
3answers
737 views

Directory appears as file?

So we copied some photos in a directory across to a NTFS partition last night, and they were viewable from ubuntu. Today the directory is not accessible from Windows, and when we booted back into ...
0
votes
1answer
111 views

Meaning of chmod 1775

Created a folder "Sample_dir" and analysed its permissions. $ mkdir Sample_dir $ ll Sample_dir/ total 36 drwxrwxr-x 2 user user 4096 Jul 1 19:26 ./ drwx------ 71 user user 28672 Jul 1 19:26 ../ ...
1
vote
1answer
342 views

reliable way to give all read/write access recursively in CentOS 7

What is the most reliable way to give all users read/write privileges for a given directory and all of its subdirectories and files in CentOS 7? In an eclipse web application project that uses ...
5
votes
2answers
1k views

Directory special permission problem

When I write: chmod g=rws,u=rwx,o=rx folder_name I get: drwxrwSr-x But S is not the same as s, right?
20
votes
5answers
3k views

Understanding UNIX based permissions and their attributes

I've never really got how chmod worked up until today. I followed a tutorial that explained a big deal to me. For example, I've read that you've got three different permission groups: owner (u) ...
1
vote
2answers
55 views

shell or perl script to check group have read privileges

ls -l drwx------ 8 ws web 1024 Apr 29 2013 abc drwxr-xr-x 8 ws web 1024 Oct 19 2011 def I need some script to find directories like abc which doesn't have read/execute permissions ...
7
votes
3answers
74k views

Create file in folder: permission denied

I'm a newbie in the GNU/Linux-Ubuntu world. I have a problem copying files to a directory on Ubuntu 12.04. I create a directory in the home directory so that the path where I want to copy to is: ...
1
vote
1answer
69 views

Linux Root group change chmod for root owned to 770

I'd like to have normal user account assigned to root group (which I've done already) and change mod of all files that are owned by root user to 770, If I understood it well in result of that every ...
4
votes
2answers
13k views

Change permissions for a symbolic link

I have a symlink with these permissions: lrwxrwxrwx 1 myuser myuser 38 Aug 18 00:36 npm -> ../lib/node_modules/npm/bin/npm-cli.js* The symlink is located in a .tar.gz archive. Now when I ...
1
vote
2answers
152 views

Permanently change permissions of /var/run/postgresql

On Linux Mint 17.0 Cinnamon Edition, I want to use /var/run/postgresql as the unix_socket_directories option for all of my postgres databases. Whenever I run the command pg_ctl -D postgres-data -o ...
2
votes
1answer
47 views

How to delete stubborn directory?

I'm having issues with dropbox so I'd like to uninstall and reinstall it. To do so I need to remove ~/.dropbox-dist but no matter what I do it won't budge. If I run ls -l I get: drwxr-xr-x 3 user ...
6
votes
3answers
469 views

How do Linux permissions work when a process is running as a specific group?

This is something I haven't been able to find much info on so any help would be appreciated. My understanding is thus. Take the following file: -rw-r----- 1 root adm 69524 May 21 17:31 ...
1
vote
1answer
167 views

How to create a Samba share that is writable from Windows without 777 permissions?

I have a path on a Linux machine (Debian 8) which I want to share with Samba 4 to Windows computers (Win7 and 8 in a domain). In my smb.conf I did the following: [myshare] path = /path/to/share ...
0
votes
1answer
34 views

What's the inverse of the X mnemonic in chmod?

Is there a way other than find … -type f -exec chmod -x {} + to remove the x bit from u, g and/or o recursively with just chmod? The X mnemonic in chmod allows one to recursively set permissions on a ...
0
votes
1answer
33 views

File Permissions issue from same group

I have a folder that I haven't created and belongs to a web-group group. Even though my username is under that group I can't modify files or create new ones without doing sudo. When I do the ...
3
votes
1answer
178 views

How to create a folder which will change its contents’ ownership to what the folder has?

In a GNU/Linux OS there is no way to change ownership of a file until you are root. But what if I want to hide my system’s username e.g. before sending a file to someone, because some things like tar ...
1
vote
3answers
124 views

How to change the permission and group-owner of a file at the same time

For changing file permission, I know I could use chmod. For changing group-owner, I could use chgrp. However, if I want to change both permission and owner at the same time, any command I could use on ...
0
votes
0answers
43 views

kickstart does not chmod a file in %post section

I have the following code executed in the %post section of a kickstart file for RHEL 6.6. echo '#!/bin/sh' > /root/add_user echo 'if [ $# -lt 1 ]; then echo "no username provided"; exit 1; fi' ...
2
votes
1answer
41 views

What are the minimum privileges the owner needs on a file to still do a chmod on a file?

I have a file with 020 privileges on the file, and I can't delete it or perform a chmod on the file. Do you know what the minimum privileges the owner needs on a file to still do a chmod on a file? ...
2
votes
1answer
61 views

Setuid, SUID bit not providing root privileges

I've written and compiled a short program to allow any user to change the contents of my /sys/class/backlight/intel_backlight/brightness file, but I fail to escalate their permissions. What could I be ...
1
vote
1answer
114 views

Sticky bit and users with sudo permission

Let's say I chmod 1777 a folder /opt/test and all files inside it as user user1. Hence user2 is able to update and edit files inside the /opt/test directory. When user2 operates via sudo, he's able ...
2
votes
2answers
39 views

Broke permissions on /bin, /boot, and /dev; how to clean the mess?

I just made a terrible mistake, I tried to fix it by myself but I need some help. Due to a syntax error all files and folders permissions were being changed: thankfully I saw this while it was ...
4
votes
3answers
109 views

mkdir permissions do not correspond to umask (change depending on location)

Whenever I create new directories in my home (or its subdirectories) they do not have write permission, even though umask is set correctly. Files I make DO have write permission. [mmanary@seqap33 ~]$ ...
1
vote
0answers
26 views

Centos 7 FTP Hidden Directory Issue

After setting up Centos 7 with a web server standard install and LAMP stack. I installed vsftpd. Everything works fine and configured it to accept passive to enable gui ftp programs. However, when ...
0
votes
1answer
126 views

Accidentally removed execute permission from root directory.

I accidentally did chmod 770 / which removed all access to the system. I booted to rescue mode, dropped to root shell and tried to chmod 755 /, but I get message changing permissions of /: read-only ...
0
votes
1answer
47 views

enable to write to file inspite we remove all file permissions

something isn’t clearly for me when I remove all permissions from file as chmod 000 I expected to get permissions denied when I write to file but still I can write to file as the following example can ...
0
votes
0answers
129 views

DD-WRT: /tmp exec permission

After making a simple hello world OpenWrt package I installed it to the /tmp folder on the dd-wrt device. The program shows up in ls /tmp but when I try to execute it, it shows me /tmp/helloworld: ...
16
votes
4answers
8k views

Wrongly set chmod / 777. Problems?

I was trying to run chmod -R 777 ./ but ended up typing chmod -R 777 / and set 777 on my entire machine. What can go wrong? How can I fix it?
0
votes
1answer
76 views

Mess with permission files [duplicate]

i've written chmod 755 /etc/ and chmod 0644 /etc/ and now i find myself without access to anything,and inside the terminal where before there was username@system1: now there's I have no name!@system1: ...
5
votes
2answers
3k views

chmod + silent mode + how force exit code 0 in spite of error

Is it possible execute chmod and ignore error from command Example ( remark file.txt not exsist to show the example ) When I type chmod 777 file.txt I get error on the output chmod: cannot ...
2
votes
1answer
80 views

Why does chmod succeed on a file when the user does not have write permission on parent directory?

I am trying to understand file/dir permissions in Linux. A user can list the files in a directory using cd test ls -l Even if the user issuing above commands does not have read, write or execute ...
0
votes
4answers
154 views

Applying different permissions to files vs. directories

Sunny answered the question above in this post, The answer was given as No need for scripts. // Directories: find . -type d -exec chmod XXX {} \; // Files: find . -type f -exec chmod ...