Sponsored Content
Full Discussion: setuid & sticky bit
Top Forums UNIX for Dummies Questions & Answers setuid & sticky bit Post 302578014 by Corona688 on Wednesday 30th of November 2011 01:46:48 PM
Old 11-30-2011
Quote:
Originally Posted by kkalyan
Can anyone explain me difference between setuid and sticky bit?
It's the same bit. It just has different meanings in different places.

I don't think it means anything for an ordinary file.

For an executable file, it runs the program as the file's owner -- it sets the UID with the setuid() call,, hence you sometimes hear it called "setuid bit". setuid doesn't work for shell scripts.

For a library file, it means 'remember the contents of this file in swap space', a performance tweak to keep busy libraries closer to memory. Many systems don't honor this anymore.

For directories, it means "only a file's owner is allowed to delete files in this directory". The usual behavior is that anyone with write-permissions can delete files.
Quote:
and also between setuid and chown?
setuid is a flag. chown is a program.
 

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

Sticky bit

I have a questions, whose answer may be very obvious: Of what use is the sticky-bit permission on a Unix system? I have looked at the chmod(1) man page on our HP-UX playground system, and haven't been given much explanation: Add or delete the save-text-image-on-file- execution (sticky... (3 Replies)
Discussion started by: LivinFree
3 Replies

2. UNIX for Dummies Questions & Answers

sticky bit??

I have a script that I want to be able to let user 'wcs1234' execute it, but when it runs, it will do so under the higher authority of 'cdunix'. It is my understanding that I accomplish this with a sticky bit. I have tried every variation of this but am unable to get this to work. my script is... (2 Replies)
Discussion started by: hedrict
2 Replies

3. UNIX for Advanced & Expert Users

setuid sticky bit

I have a binary. It is having the following permissions rws rws rwx mqm:mqm runmqtrm The same program on another machine is rws rws rwx root: mqm runmqtrm This program is a setuid program. This is what my understanding is. Whatever user the program is started under, it will finally be... (0 Replies)
Discussion started by: bandaru
0 Replies

4. UNIX for Dummies Questions & Answers

Sticky Bit

I have the sticky bit set on my /tmp directory, but users are still able to remove files that are not owned by them. Does the /etc/group file get invloved in securing these files ?? (1 Reply)
Discussion started by: rob11g
1 Replies

5. Shell Programming and Scripting

sticky bit

Hi frns, What is command to list out all dir's for which sticky bit has been set. Regards, Manu (2 Replies)
Discussion started by: manu.vmr
2 Replies

6. UNIX for Dummies Questions & Answers

Question regarding permision and seguid bit (sticky bit)

Hi , I am having file permision as drwxrwsr_x I kwo for deleting a file in the diretory i need w permsion as well .. Say if i am having the permsion as drwxrwsrwx - wil any one can delete the files in the directory .. And one more question what is the s doing there ..... (2 Replies)
Discussion started by: arunkumar_mca
2 Replies

7. UNIX for Dummies Questions & Answers

Sticky Bit????

HI What is sticky bit? how can be see if the sticky bit for file is set? WHat is meaning of sticky bit set on Directory? What is the syntax to set the sticky bit? With example Thanks (10 Replies)
Discussion started by: skyineyes
10 Replies

8. Shell Programming and Scripting

Sticky Bit

I want a file I create to not be deletable by other users so I created a sticky bit by chmod 1644 on the file. chown'd it to root and then tried to delete (via GUI drag to trash and empty) as a non root user and it let me. is sticky bit only good for terminal deletes or something? (4 Replies)
Discussion started by: glev2005
4 Replies

9. AIX

sticky bit

as far as i understand, if sticky bit is set on a directory, the files created under tht directory cannot be deleted by ordinary user... but we can do ths by permission itself,,, tht's assign only read permission to tht dirrectory wht 's the difference? (1 Reply)
Discussion started by: udtyuvaraj
1 Replies

10. UNIX for Beginners Questions & Answers

What keeps me from abusing setuid(0) and programs with setuid bit set?

Just learning about the privilege escalation method provided by setuid. Correct me if I am wrong but what it does is change the uid of the current process to whatever uid I set. Right ? So what stops me from writing my own C program and calling setuid(0) within it and gaining root privileges ? ... (2 Replies)
Discussion started by: sreyan32
2 Replies
SETUID(1)						      General Commands Manual							 SETUID(1)

NAME
setuid - run a command with a different uid. SYNOPSIS
setuid username|uid command [ args ] DESCRIPTION
Setuid changes user id, then executes the specified command. Unlike some versions of su(1), this program doesn't ever ask for a password when executed with effective uid=root. This program doesn't change the environment; it only changes the uid and then uses execvp() to find the command in the path, and execute it. (If the command is a script, execvp() passes the command name to /bin/sh for processing.) For example, setuid some_user $SHELL can be used to start a shell running as another user. Setuid is useful inside scripts that are being run by a setuid-root user -- such as a script invoked with super, so that the script can execute some commands using the uid of the original user, instead of root. This allows unsafe commands (such as editors and pagers) to be used in a non-root mode inside a super script. For example, an operator with permission to modify a certain protected_file could use a super command that simply does: cp protected_file temp_file setuid $ORIG_USER ${EDITOR:-/bin/vi} temp_file cp temp_file protected_file (Note: don't use this example directly. If the temp_file can somehow be replaced by another user, as might be the case if it's kept in a temporary directory, there will be a race condition in the time between editing the temporary file and copying it back to the protected file.) AUTHOR
Will Deich local SETUID(1)
All times are GMT -4. The time now is 07:50 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy