[SOLVED] Directories are created with chmod 777. Why?

ddenial · 01-25-2018, 05:27 AM

Hello,

It's strange that I noticed my new directories with command mkdir are being created with permission 777 instead of 755. I don't recall any explicit changes I did to any of my configurations.

It's only happening on a particular mounted partition. If I create a directory in any of my Home directories its created correctly with permission 755.

Code:

$ cd ~

$ umask
0022

$ mkdir TestDir

$ ls -ld TestDir/
drwxr-xr-x 2 tuser tuser 4096 Jan 25 16:45 TestDir/

$ sudo umount /dc

$ ls -ld /dc
drwxrwxr-x 2 tuser tuser 4096 Jan 15 13:50 /dc

$ sudo mount /dev/sda2 /dc

$ ls -ld /dc
drwxr-xr-x+ 27 tuser tuser 4096 Jan 25 16:49 /dc

$ cd /dc

$ umask
0022

$ mkdir TestDir2

$ ls -ld TestDir2
drwxrwxrwx+ 2 tuser tuser 4096 Jan 25 16:51 TestDir2

Code:

$ grep '/dc' /etc/fstab
# /dc was on /dev/sda2 during installation
UUID=42ce5151-28f1-4567-b7b4-0b5a27e91721 /dc             ext4    defaults        0       2

$ mount | grep 'dc\|svr'
/dev/mapper/mvg-svr on / type ext4 (rw,relatime,errors=remount-ro,data=ordered)
/dev/sda2 on /dc type ext4 (rw,relatime,data=ordered)

What could be wrong?

Appreciate any help. Thanks

sgrlscz · 01-25-2018, 06:54 AM

The + on the ls output indicates there is an ACL on /dc. Based on the fact that /dc/TestDir2 also has an ACL, it looks like there is a default ACL involved (TestDir2 inherited a default ACL from /dc). ACLs can affect how the mode of a file appears. It can look like it's giving more permission than it actually is simply because the ACL can't be accurately reflected in the mode.

You can use the 'getfacl' command to look at the ACLs on /dc and /dc/TestDir2. That will give you a clearer picture of the permissions.

Rickkkk · 01-25-2018, 07:21 AM

Hi ddenial,

Building on sgrlscz's advice, I would recommend you read up on the umask function. It doesn't always treat files and directories the same way and different distros can set default behaviour in different ways. It is an often misunderstood (at least partially) function.

I don't know what distro you are using, but :

... start with a search of any documentation it provides on how umask is configured by default.
Then, a look at the manual entry for umask could also be helpful:
Code:
```
man umask
```
The Arch Linux Wiki has (as usual) an excellent entry on umask - worth your time:

https://wiki.archlinux.org/index.php/Umask

Cheers and let us know how you make out !

ddenial · 01-25-2018, 07:27 AM

Quote:

Originally Posted by sgrlscz

The + on the ls output indicates there is an ACL on /dc. Based on the fact that /dc/TestDir2 also has an ACL, it looks like there is a default ACL involved (TestDir2 inherited a default ACL from /dc). ACLs can affect how the mode of a file appears. It can look like it's giving more permission than it actually is simply because the ACL can't be accurately reflected in the mode.

You can use the 'getfacl' command to look at the ACLs on /dc and /dc/TestDir2. That will give you a clearer picture of the permissions.

Thanks. It really helped.

I don't know how ACL was set. This was the result of getacl

Code:

$ getfacl /dc
getfacl: Removing leading '/' from absolute path names
# file: dc
# owner: tuser
# group: tuser
user::rwx
user:tuser:rwx			#effective:r-x
group::r-x
group:tuser:r-x
mask::r-x
other::r-x
default:user::rwx
default:user:tuser:rwx
default:group::rwx
default:group:tuser:rwx
default:mask::rwx
default:other::rwx

After some web search, and with the following command, the problem is gone.

Code:

$ setfacl -b /dc

$ getfacl /dc
getfacl: Removing leading '/' from absolute path names
# file: dc
# owner: tuser
# group: tuser
user::rwx
group::r-x
other::r-x

Thanks