chmod 4755 (rwsr-xr-x) gives (rwxrwxrwx)

Question

I want to get the permissions of a program, call_shellcode (which calls shellcode), to be set to -rwsr-xr-x. When I run:

sudo chmod 4755 call_shellcode

the permissions for some reason is still set at -rwxrwxrwx

I am trying to get the root shell, but when I execute the program I get a normal shell. I am using Ubuntu 16.04 (32-bit) in VirtualBox

Solution

You are running gcc as root for some strange reason, but then you run the chmod as your regular user. You don't have [permission to change the rights of call_shellcode since you compiled it as root, and therefore the permissions remain unchanged.

Don't compile as root! Don't do anything as root unless you have to.

Comments

[Zanna]

Is this file on an NTFS partition or something like that?

[PerlDuck]

Please don't post pictures of your problem! Post it as text instead.

[James]

It is in a shared folder between host and guest for the VM

[Connor Payne]

Who is the owner of the file? you can find this out by running ls -l on the directory.

[terdon]

Is that really the only error message you get? Nothing about Operation not permitted?

[James]

Yeah it only shows what is there

[Yaron]

please edit your question, and add the result of ls -l in that directory

[James]

I just tried gcc -o call_shellcode call_shellcode.c without the sudo and it still doesnt work

[Yaron]

@JamesTan - the file call_shellcode already exists and owned by root, you need to sudo rm call_shellcode before running the gcc as regular user