Questions tagged [chmod]
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 sticky bits.
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Is there a standard way of making a copy of file/folder permissions to apply/compare later?
I'm copying a bunch of files to a filesystem that doesn't support permissions. however, I will need to copy them to another filesystem which does support permissions a few years from now. at that ...
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chmod command output: cannot access '/root/server/app.sock': No such file or directory while file exists
I run the command sudo chmod 777 ~/server/app.sock on my server and it works appropriately and changes the permission.
However, when I run this command through github action, it doesn't work and says:
...
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Tried accesing my custom shared object, but permission is denied
Created a basic C++ shared objects file using g++:
// calculate.hpp
#ifdef __cplusplus
extern "C"
{
#endif
// typedef struct ...;
// function decls
int Add(int x, int y);
#ifdef ...
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Linux Ubuntu 20.04 - ownership changed to root for entire drive - permission changed to 777 for all files, cannot revert
I am running Linux Ubuntu 20.04 and for some reason unknown to me, one of my storage drives suddenly has changed ownership to root and all file permisions are read/write/execute for all users. A ...
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What is the value for rwSrwSrwT?
The value 1777 is the permission of rwxrwxrwt:
touch target.txt
chmod 1777 target.txt
ls -al target.txt
-rwxrwxrwt 1 debian debian 0 Jul 14 20:24 target.txt
I have to get a permission string of ...
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Why is chmod working inconsistently between files?
I am making 3 sites in Drupal and need to frequently change the settings.php file in each website folder. This file is read-only for security reasons by default, so before I can edit it, I use:
chmod ...
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How can I grant a user group permission to start/stop a custom service?
I have a service that exists in the root directory and I want to give user group admin permissions to run the service.
The service exists in /root/home/custom_service/service.service
I tried chgrp ...
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Not able to give write permission to other user with ACL or chmod
Anyone know why rocky can't write to /tmp/afile? Giving rocky permission as an other user with chmod o+w doesn't seem to work either 🤔
I updated the acl with: setfacl -m u:rocky:rw /tmp/afile
id as ...
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Why is an open inode system call a security risk?
According to the accepted answer here, it is simply because you would not make the access checks at the directories leading up to that file. For example, with a call to openinode(inode #, flags).
My ...
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Nginx Permission denied
I am using Nginx to serve static files from server. Static file is located in root folder, /server/cdn. I give all permission to this folder with sudo chmod 777 -R server command. Also I changed the ...
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chmod not working on NTFS-3g partition
I have a file on an NTFS-3g partition, I tried using chmod to add execute to this file, but it remained unchanged.
What am I doing wrong? I followed this and this posts, but none of them worked, this ...
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Cannot open files in texlive directory
I've installed texlive 2023 via tlmgr, the directory is /usr/local/texlive/2023/ and update it with sudo tlmgr --self --all --no-auto-remove update as I've been doing it for years. It works perfectly ...
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Does Linux clear set-group-ID bit for a file is the group ID of the file doesn't match?
I was going through the amazing book The Linux Programming Interface. In that chapter 15, section 15.4 page no 304, it is written that:
For this reason, when an unprivileged process (one that doesn't ...
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What File Permissions to use for Docker Owned Files
So ive got a ubuntu server install with docker thats running a few containers and ive got folders for each now im wondering what would the logical permissions be for the files it cant be 777 right? it ...
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rsync permission denied - but they have full 777?
It is getting late and I am loosing my mind ...
I have a data drive (NTFS) which I used to share in an Windows/Ubuntu dual boot system. After an upgrade it is currently Windows 10 and Ubuntu running ...
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Why does adding a user and setting an SUID for it throws me the "Operation not permitted" error?
I am setting SUID for a new user tommy to run the same commands as root but it goes down like this:
[root@192 ~]# useradd tommy
[root@192 ~]# su - tommy
[tommy@192 ~]$ chmod u+s /usr/bin/ls
chmod: ...
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preventing linux user from chmod 777
With /etc/login.defs having UMASK 007 or UMASK 027 for example will result in created files not having world rwx permissions. But a user can chmod 777 file they own correct? Also for home accounts, ...
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Access rights through group which limits modifying/deleting others files
(I previously posted this on superuser, but thinks this question is a better fit for this stackexchange...)
Let's say I have a directory some_dir, and a group some_group with a number of users. I ...
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Allow user in group to access shared folder from another user
There are two accounts user1 and user2. I wish to share and give rwx access to my user1 /home/user1/Documents/ folder with user2. To do this, I have made a new group called sharedDocs. These are the ...
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Is it possible to revoke delete permissions with Linux permissions or ACL's?
If i wanted to create a directory that is owned by a user don and the group owner was a group called bob, would there be any way to:
Allow the group (bob) to have permissions to create and write to ...
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macOS ACL settings - unable to delete Time Machine backup left-over files
(macOS Ventura - MacBook Pro M1)
I have deleted Time Machine backup file manually!! (my bad). Now I am left with files in my .Trashes folder that I cannot delete, no matter what I try.
I have enabled ...
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Force certain file permissions on files uploaded to SFTP server
I have the openssh sftp server set up to force sftp for users in the sftp group. Additionally, they are chrooted into the /srv/users/%u directory. This works fine, and users can access the directory, ...
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change a folder permission in root directory
I want to change a folder permission in root directory ( /backup like /home) when I tried
chmod 755 /backup
it changes for a day and after a day its permission changes back. how can I change it ...
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Unable to see thumb drive through file manager
I am using EndeavorOS with i3 and am trying to put stuff on a thumb drive, but Thunar file manager isn't seeing it. When I run fdisk -l and lsusb I see the thumb drive, but it doesn't show up in ...
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Does "chmod u+w" mean give the user (owner) writing permissions ("2XY" in octal)?
I understand that chmod u+w means give the user/owner (u), writing permissions (w, which is equivalent to the number 2), so the new permissions of the file after running the chmod command above would ...
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What does chmod u+w mean and is there a longer but clearer command? [duplicate]
Say I run for example, chmod u+w web/sites/default.
What does chmod u+w mean and is there a longer but clearer command?
I understand from man chmod that u here means user (owner), but what is w here? ...
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marking the contents of a directory read-only
I'd like to mark a directory as read only in a way that would make it's contents read-only. Using chmod a=rx makes the directory read/executable only, so it and its contents can't be deleted. That's ...
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No write permissions for bootable usb
Background: I'm installing Windows for the DOS laptop for the first time, I've never done it before. There is a second laptop with Ubuntu 16. I downloaded the image from the official site, created a ...
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Do I need to reformat my drive?
Learning the hard way that you can't change the permissions of an exfat volume.... I need to be able to scp from Windows to an external hard drive on my Ubuntu Server without using an intermediary ...
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Can you make a proxy file system?
Is it possible on Linux to create a proxy file system? So the idea is to have all the file operations done on one file system, but to have all the contents saved on another file system.
The problem I ...
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How can I revert a chmod -R +x on the etc directory?
I'm running Ubuntu 20.04.5 LTS and I messed up with the chmod -R command!
I mistyped the directory while running chmod
and instead of chmod -R +x ./etc I wrote chmod -R +x /etc.
So now everything in /...
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read write file permission in linux
I have Ubuntu WSL with default username wsl and new user with username newuser
List all files :
wsl@Optiplex:~$ ls -la
total 176
drwxr-xr-x 13 wsl wsl 4096 Nov 1 06:36 .
drwxr-xr-x 4 root root ...
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sudo not working after chmod -R 777 /bin at wrong location
By mistake i executed below command
[root@ip-172-31-71-252 ~]# chmod -R 777 /bin
and location was
[root@ip-172-31-71-252 ~]# pwd
/root
Then I logged out of from root session and tried 'sudo -i' I am ...
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How to allow users of a group to have the same permission of the owner?
I'm not a linux expert and I would like to know how can I fix this situation:
there is an user called demo which have as id 1000, this user is associated to www-data group, so the demo user can ...
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How do I have two group owners
I have a file where I want there to be not one but two groups who can have extra privileges to access it. But when I chown or chgrp it to a group it always erases the previous group. How do I add a ...
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I accidentally disabled execution of all files on my OS
sudo chmod -333 /
The system expectedly doesn't work. I'm wondering if there are any ways to get it back up besides reinstallation?
My operating system is Debian.
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Can't change mounted HDD's permissions at all
I'm new to Ubuntu.
I installed Ubuntu on my PC which has SSD and HDD. I followed the guide to partition HDD properly and it has been mounting without errors so far. However, I can't write anything in ...
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Permission Error
I have installed bash shell in windows 10 to run linux commands. I am trying to execute a script which gives error "You do not have permission to edit". I have executed command "chmod ...
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Best way to source config file inside sudo user .bashrc file?
I'm building a LEMP stack script powered by bash scripts and CLI aliases. For security reasons, all of the bash scripts, and the stack config file (also bash syntax) are owned by root:root.
I added ...
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Is there ever a good reason to add users to the "root" group?
There is much discussion online about creating sudo users and groups, editing the sudoers file, etc.
For example, you might have sensitive configuration files or shell scripts, and you set the file ...
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How to restrict read access to directory for specific user in centos?
So here is the deal, I create directory /home/accounting, I have users donna and mike and I want to restrict read privileges for them to this directory.
After going to Google I was able to find how to ...
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chmod adding only write permission for user [duplicate]
I am new to linux. I learnt about chmod command, and was trying to do some practice. There is a file named "a". Initially this file has no permissions for user, group, and other user. I ...
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How to make a folder can't be deleted and be modified folder name. But you can still add files in it?
I want to make a shared disk with people online using ubuntu VPS. So as the title says, I want to make a folder can't be deleted and be modified folder name. But you can still add files in it (it's ...
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What is the meaning of chmod -R a-x,a=rX,u+w?
What is the meaning of chmod -R a-x,a=rX,u+w?
chmod changes file permissions, -R makes it be done recursively but what are:
a-x
a=rX
u+w
here?
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SFTP Only Users Unable to Delete/Edit Files They Create
I modified /etc/ssh/sshd_config with these lines to support an sftp user group that isn't able to SSH.
Subsystem sftp internal-sftp -l VERBOSE
Match Group sftpusers
X11Forwarding no
...
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Using "chmod -R 666 filename" does not give all files writing permissions
I have been running as root in a Linux Virtual Machine to change permissions to a whole list of files within a directory. When I check the permissions after using sudo chmod 666 -R /home/candidate/...
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Do group permissions matter for files owned by the root group?
I've stumbled upon a script which included the following two commands:
chown -R some-user:0 /some/dir
chmod -R g+w /some/dir
Specifically, this is from the Dockerfile of the nginx-unprivileged Docker ...
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What permissions are needed to prevent a group from writing to or deleting a file?
myfile permissions: group has rwx
mydir permissions: group has rwx
Problem: user1 wants to prevent group members from writing to myfile or deleting myfile
What chmod options are needed to achieve ...
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give access to /home/$USER/targetfolder only to me and a partner
I'm working on a server where current users (group=domainusers gid=1002) can read, write and run ONLY our own files.
Because of my kind of permissions I'm not able to run apt | adduser | addgroup | ...
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