How to fix permission denied error in Linux? [Solutions]

Linux permission denied error: When you are working with the Linux Operating system, a common error occurs i.e., permission denied. In this article, you will get to know about how to 'permission denied' error in Linux.[linux permissions denied]

Last Updated: by Susith Nonis 16 Min
How to fix permission denied error in Linux? [Solutions]

In the Linux Operating System, you cannot execute any command without proper permission. Every file and directory has some permission or privilege (read, write, or execute) associated with them. If you are not authorized to access the file or directory, executing any command on that will result in a "permission denied" error in Linux. This prevalent problem can only be resolved by getting the proper access to that file and directory. In this article, we will help you with how to fix the permission denied errors in Linux and what type of error this is.

Quick Answer: Diagnose Permission Denied in Linux

If you're seeing a Linux permission denied error, don't start by throwing chmod 777 at it. Most of the time, the fix is simpler — and safer — once you know whether the problem is the current user, the file mode, the ownership, the parent directory, or a security policy like noexec or SELinux.

Flowchart showing Linux permission denied troubleshooting steps from whoami to SELinux checks
Flowchart showing Linux permission denied troubleshooting steps from whoami to SELinux checks

Step 1: Check the current user

First, confirm who you are and which groups you belong to. You'd be surprised how often the wrong shell session or an unprivileged user is the whole issue.

whoami id

If the file is owned by root or another account and your user isn't in the right group, Linux will block the action even if the file looks fine at a glance.

Step 2: Inspect file or directory permissions

Next, check the mode bits. For a file, use ls -l. For a directory, use ls -ld.

ls -l file.txt ls -ld mydir

If your script won't run, look for the execute permission. If cat fails, check read permission. If cd fails, inspect the directory execute bit — that's the one people miss constantly.

Step 3: Check ownership and parent directory access

Then inspect ownership and the path above the file. A file can have usable permissions and still be inaccessible because a parent directory blocks traversal.

stat file.txt ls -ld . ls -ld /path/to/parent

Quick Troubleshooting Checklist

  1. Re-run the exact command and read the full error.
  2. Check user identity with whoami and id.
  3. Check file or directory permissions with ls -l or ls -ld.
  4. Check ownership with stat.
  5. Check parent directory permissions.
  6. If all that looks right, inspect mount options, ACLs, and SELinux/AppArmor.

Jump to your error if you already know the symptom:

  • script won't run — see the ./script.sh: Permission denied section
  • cannot create file — see touch and directory write permissions
  • cannot remove file — check directory write permission and sticky bit
  • cannot open directory — check the directory execute bit
  • cd permission denied — inspect parent and target directory traversal permissions

What is Linux Permission Denied Error?

This type of error will occur whenever you run a command for which you do not have the execute permission. Similarly, you cannot perform read or write actions if you do not have read or write permission for any file or directory. These Linux permissions are the primary reason behind the security of Linux, as they will help in protecting the data from unauthorized access.

Linux permission matrix showing owner, group, others, rwx columns, octal values, and file vs directory execute meaning
Linux permission matrix showing owner, group, others, rwx columns, octal values, and file vs directory execute meaning

Understanding Linux File Permissions

  1. Read (r): Allows users to view the content of a file or list files in a directory.
  2. Write (w): Enables users to modify file contents or create/delete files within a directory.
  3. Execute (x): Allows running executable files (scripts, binaries) or traversing into a directory.

These permissions are set for three categories of users:

  • Owner (u): The user who owns the file or directory.
  • Group (g): A specific group of users to which the file or directory belongs.
  • Others (o): All other users who are not the owner or part of the group.

In addition to these basic permissions, Linux also supports advanced features like setuid, setgid, and the sticky bit, which influence how permissions work for certain files and directories.

How to Check Permissions

To check your privileges for a specific file or folder, use:

ls -la

ls command displays the long listing of all files and folders along with their permissions, as shown below.

ls command

In the example below, we have created a shell script "hello.sh" without the execute permission. On executing "hello.sh", you will get a permission denied linux error.

permission denied

You can also use stat for more detail including ownership and timestamps, whoami to confirm your current user, and id when group access matters.

stat hello.sh whoami id

Common Causes of Permission Denied in Linux

Most Linux permission denied problems fall into a few clear categories. Understanding these helps you quickly identify the root cause.

1. Missing execute permission on a script

Symptom: ./script.sh: Permission denied. The script file lacks the execute permission. Verify with ls -l script.sh and fix with chmod +x script.sh or run it through the interpreter with bash script.sh.

2. Wrong owner or group

Symptom: you can see the file, but you can't edit or delete it. Common with root-owned files under /etc, shared project folders, or files created by another service account. Fix with chown or chgrp rather than just chmod.

3. No access to the parent directory

Symptom: cannot open directory '.': permission denied, cd permission denied, or file access that fails even though the file itself has good permissions. If the parent directory lacks execute permission for your user or group, you can't traverse into it.

4. Commands that need sudo privileges

Symptom: editing files in /etc, accessing /root, installing software packages, or modifying system configuration files fails. These tasks require elevated access through sudo or root login.

5. Software Installation and System Configuration

When attempting to install or update software packages using apt, yum, or dnf, you may encounter "Permission Denied" errors if you lack the necessary privileges. Similarly, modifying system configuration files in /etc typically requires root or sudo access.

6. Filesystem mounted as read-only or noexec

Symptom: write operations fail even with correct permissions, or scripts refuse to execute despite chmod +x. Verify with mount. A read-only mount blocks writes; a noexec mount blocks direct execution.

7. SELinux or AppArmor restrictions

Symptom: everything looks correct in ls -l, but access is still denied. SELinux context mismatches and AppArmor policies can override standard Unix permissions — especially common on CentOS, RHEL, AlmaLinux, and Rocky servers.

8. Network and Shared Directory Access

In networked environments, accessing shared directories or files on remote servers (via NFS or Samba) may result in "Permission Denied" errors if proper access permissions aren't granted on the remote system.

How to Fix Permission Denied: chmod, chown, and chgrp

To solve permission errors, you need to add the correct permissions. However, you need to be a "root" user or have sudo access to change permissions. Linux offers the chmod command (change mod) for modifying permissions, chown for changing ownership, and chgrp for changing group.

Side-by-side comparison of chmod, chown, and chgrp with uses and example commands
Side-by-side comparison of chmod, chown, and chgrp with uses and example commands

Using chmod: Symbolic and Octal Representation

The chmod command uses this syntax:

chmod flags permissions filename

  • Flags: Additional options like -R for recursive changes.
  • Permissions: Can be in symbolic form (r, w, x) or octal numbers (0-7).
  • Filename: The file or directory whose permissions you want to change.

Symbolic Representation

chmod u=rwx,g=r,o=r file

Where:

  • u=rwx — Owner gets read, write, and execute permissions.
  • g=r — Group members get read-only access.
  • o=r — All other users get read-only access.

Octal Representation

chmod 744 file

Where:

  • 7 (owner) = 4(read) + 2(write) + 1(execute) — full access.
  • 4 (group) = read-only.
  • 4 (others) = read-only.

Common chmod examples:

chmod u+x hello.sh # Add execute for owner chmod 744 hello.sh # Owner full, group/others read-only chmod g+w notes.txt # Add write for group

Changing File Owner with chown

If you don't own the file, permission changes may fail or not solve the actual problem. This is common after copying files with sudo, extracting archives as root, or editing files from the wrong account.

ls -l file.txt sudo chown username:username file.txt

Changing Group Access with chgrp

Useful on team systems where several users share files through a common group.

sudo chgrp developers file.txt chmod g+rw file.txt

Step-by-Step: Fixing Script Permission Denied

Now let's walk through a real example. Below, we have the error:

Permission Denied Linux Error

Giving the appropriate permission to the user will solve the problem. Execute the below command to provide execute permission:

chmod +x hello.sh

Permission Denied Error

Now we can see the change in permission — the execute bit has been added. Let's run the script:

./hello.sh

Linux Permission Denied Error

After executing "hello.sh", we get the output "hello." Changing permission has solved the problem.

Stylised Linux terminal showing hello.sh permission denied, then chmod +x and successful execution
Stylised Linux terminal showing hello.sh permission denied, then chmod +x and successful execution

Alternative: Run the script with bash

If direct execution fails but the script itself is valid, run it through Bash:

bash script.sh

This bypasses the need for the file itself to be executable. If you're new to scripting, here are good basics on how to run shell scripts in Linux.

Check the shebang and line endings

If chmod +x doesn't help, inspect the first line and the file format:

head -n 1 script.sh file script.sh

Make sure the shebang points to a valid interpreter, like #!/bin/bash. Also watch for Windows CRLF line endings — use dos2unix to convert them if needed.

Fixing Permission Denied by Command Type

Here's how to troubleshoot the most common error messages quickly.

touch: cannot touch ... Permission denied

You don't have write permission on the destination directory. Check the current directory permissions, not the file you're trying to create — because it doesn't exist yet.

ls -ld . chmod u+w .

rm: cannot remove ... Permission denied

This is usually about the directory, not the file. To delete a file, you need write and execute on the parent directory. If the directory has the sticky bit set (like /tmp), you may only delete files you own.

ls -l file.txt ls -ld .

mv: cannot move ... Permission denied

You lack write access on the destination directory, or source and destination ownership rules conflict.

ls -ld /target/path chmod u+w /target/path

cat: Permission denied

The file isn't readable by your user. Check the read bit.

ls -l secrets.txt chmod u+r secrets.txt

cd: Permission denied

The target directory isn't traversable. You need execute permission on the directory itself and every parent directory in the path.

ls -ld /path/to/dir chmod u+x /path/to/dir

cannot create regular file: Permission denied

Same root cause as touch errors — check write and execute on the parent directory.

chmod u+rwx mydir

Fixing Directory Permission Errors

Directory permissions in Linux work differently from file permissions. Here's what you need to know.

Stylised terminal graphic showing ls -ld on . and .. with missing execute bit causing cd permission denied
Stylised terminal graphic showing ls -ld on . and .. with missing execute bit causing cd permission denied

Directory Execute Permission

On a directory, execute permission means you can enter or traverse into it. Without it, commands like cd, ls, or access to files inside may fail even if the file permissions themselves look correct.

Fix cannot open directory '.': permission denied

This means the current directory lacks read or execute for your user. Check both:

ls -ld . ls -ld ..

If the current directory has no execute bit, you can't access entries inside. If it has execute but no read, you can access known filenames but can't list contents.

Directory Permission Summary

  • Read (r) on a directory = can list files inside (use ls).
  • Write (w) on a directory = can create, delete, or rename files inside.
  • Execute (x) on a directory = can enter or traverse the directory (use cd).

On shared directories like /tmp, the sticky bit also affects deletion — preventing users from removing each other's files even with write access.

What to Do When chmod Doesn't Fix the Problem

If you've changed permissions but still get Linux permission denied, the issue lies deeper.

Check for noexec mount option

mount | grep noexec

If the filesystem is mounted with noexec, no file on that mount can be executed directly — even with chmod +x.

Check SELinux context

sestatus

On SELinux-enabled systems (CentOS, RHEL, AlmaLinux, Rocky), security contexts can block access even when standard permissions look correct.

Check ACLs with getfacl

getfacl file.txt

Access Control Lists add granular rules beyond standard user/group/others. Use setfacl to modify them if needed.

Check immutable attributes with lsattr

lsattr file.txt sudo chattr -i file.txt

If a file has the immutable flag (i), it cannot be modified, renamed, or deleted until the flag is removed.

Check disk space

Sometimes "Permission Denied" errors occur due to insufficient disk space. Use the df command to verify. Low space, read-only remounts, and permission symptoms can overlap confusingly. Here's how to check disk space with df.

Ownership vs Permissions: Understanding the Difference

Permissions answer what actions are allowed (read, write, execute). Ownership answers who those permissions apply to first (user, group, others). A root-owned file with 600 permissions is accessible to root and blocked for everyone else. Many "chmod permission denied" searches are really ownership issues. If you're creating accounts for app users or team members, you'll often need to create a new Linux user first and assign proper ownership.

SELinux, AppArmor, and Mount Options

Real systems are messier than tutorial examples. Mount options can block writes or execution. SELinux can deny access based on security context. AppArmor can confine a process even when the file itself seems accessible. If you're troubleshooting storage or security-related permission issues, also check how to fix rsync permission denied errors which covers similar ground.

Safe Permission Practices

Avoid chmod 777

It often "works" but opens the door far wider than necessary. On multi-user systems, web servers, or anything public-facing, this creates real security risks.

Use the least privilege needed

If a script only needs owner execute permission, grant just that. If a shared file only needs group write access, don't grant write to others.

Test changes on a non-production file first

Recursive changes like chmod -R and chown -R can damage a system if pointed at the wrong path. Verify before executing.

Troubleshooting Tips

  1. Check Error Messages: Read the specific error message carefully — it often identifies the exact file or directory causing the problem.
  2. Review Log Files: Examine /var/log/syslog or /var/log/auth.log for relevant entries.
  3. Verify Permissions: Use ls -l for files, ls -ld for directories.
  4. Confirm Ownership: Verify who owns the file with stat or ls -l.
  5. Use sudo or su: For system-level files and administrative tasks, temporary elevated privileges may be required.
  6. Check Network Access: If accessing files over a network (NFS, Samba), ensure remote permissions are correctly configured.

Conclusion

If you are a regular Linux user, you've likely faced the "permission denied" error. The fix isn't just running chmod 777 — it's diagnosing the actual cause first. Check your user with whoami and id, inspect permissions with ls -l and ls -ld, verify ownership with stat, then apply the right fix — whether that's chmod, chown, chgrp, sudo, or adjusting mount options and security policies.

If you're managing these issues regularly on a server, spending time on Linux server administration basics will pay off quickly. You can also buy a Linux VPS server to practice and test these commands in a real environment.

Category: Tutorials Linux

FAQs About How to fix permission denied error in Linux? [Solutions]

Linux shows "Permission denied" when your user does not have the required read, write, or execute access for a file, directory, or command. The cause may be file permissions, ownership, parent directory access, sudo restrictions, mount options, or security policies like SELinux.

Use ls -l for files and ls -ld for directories. You can also run stat filename for more detail, and whoami plus id to confirm which user and groups are being checked against the permission rules.

First add execute permission with chmod +x script.sh, then run ./script.sh again. If it still fails, try bash script.sh, then check the shebang, Windows CRLF line endings, and whether the filesystem is mounted with noexec.

chmod changes permission bits such as read, write, and execute. chown changes the file owner, which is often the real fix when a file belongs to root or another user.

cd needs execute permission on the target directory and every parent directory in the path. Without the directory execute bit, you cannot traverse into that location even if the directory has read permission.

Creating files depends on write and execute permissions on the destination directory, not on the file that does not exist yet. Check ls -ld on the target directory and confirm ownership or use sudo if the location is system-protected.

chmod +x only fixes missing execute permission on the file itself. It will not help if the file is on a noexec mount, blocked by SELinux or AppArmor, hidden behind restrictive parent directory permissions, controlled by ACLs, or owned by another user.

On a directory, execute permission means you can enter or traverse that directory. Without it, commands like cd, ls, or access to files inside the directory may fail even if the file permissions look correct.

Usually no. chmod 777 gives read, write, and execute access to everyone, which is far more permission than most files or directories need and can create security risks, especially on servers and shared systems.

Check the parent directory permissions with ls -ld because deleting and moving files usually require write and execute access on the directory. Also verify ownership, sticky bit behavior on shared directories, and destination permissions for mv.

Yes. SELinux can block access even when standard Unix permissions look correct. Run sestatus to see whether it is enabled, then inspect context and audit logs if you suspect a policy denial.

Run mount | grep noexec to look for the noexec mount flag. If it appears on the filesystem containing your script, direct execution with ./script.sh will fail even if the file has the execute bit set.

Susith Nonis

Susith Nonis

I'm fascinated by the IT world and how the 1's and 0's work. While I venture into the world of Technology, I try to share what I know in the simplest way with you. Not a fan of coffee, a travel addict, and a self-accredited 'master chef'.

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