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Restricting user

I created a user account to scp a file to an NFS server:/shared/prices thru winscp from her laptop.
Our concern is if created an account for the user in Unix box, she may corrupt or move other files in this share. How can we restrict the user to be confined and not damage any files in this directory share.
File Sharing SoftwareSecurityLinux

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8/22/2022 - Mon

don't let the user own the dir. Let the owner be some other user and add the write and sticky bit to the dir hence user can add her own files and delete them but can not delete others files:

chmod +w /dir
chmod +t /dir


I have not problem with this linux zone. Go ahead

drwxr-xr-x   3 abciadmin   abcgroup      2048 May 23 15:03 pricechanges

Under this directory is

drwxr-xr-x   2 xpiadmin   xpigroup      3072 May 23 15:03 archive
-rwxr-xr-x   1 massprix       user           6031 May 23 14:12 price.csv.20080523

Massprix user is the one that always winscp the price.csv to this pricechanges directory. We wanted massprix to just copy the file and cannot delete or alter other files in the pricechanges directory. After massprix move the file to this directory , a  script will move the current price.csv.20080523 file to archive directory. Please give me the details on how I could do this with sticky bit. Will it affect other users accessing this shared directory or anything above the pricechanges directory?


I thought that the files belong to some other user. sticky bit will help in one case that you have a cron job that changes the ownership of the files to some other user (and the dir itself is owned by other user)
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William Peck

Please elaborate on your last recommendation. I cannot understand. Pleae add exaple based on the dir and accounts I submitted. Thank


I will give example and you may see how you can implement it in your case.

mkdir /mydir
chown user1 /mydir
chmod +w /mydir
chmod +t /mydir

The above commands create a dir /mydir , change ownership of /mydir to user1 , give everyone write perm on this dir, then set the sticky bit on it.

This will allow other users to create files under this dir and delete them. But, because of the sticky bit, they can not delete others files. Now, if you don't want them to delete even their files, you then change the ownership of those files, and revoke write perm on them

chown user1 /mydir/*
chmod a-w /mydir/*

Is there any problem with sticky bit on other files or apps in the directory?
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Thanks Omarfarid