Do you need read permission for C setgid?
If you’re not either user root or in group agrp, you need to be able to use the public execute permissions on the program — which are missing. Since it is a binary, you don’t need read permission. To fix it: (The # denotes ‘as root or via sudo ‘, or equivalent mechanisms.)
What happens if C-setgid ( ) fails?
I execute the program as userA/users and try to set the uid/gid to userB/otherUsers. setgid () fails with Operation not permitted. userA is not part of otherUsers How can I change the effective gid? Here is a small summary of what I did.
Why is C-setgid operation not permitted in Unix?
Classically on Unix systems, the EUID and RUID could be different, and the difference would be inherited across multiple ( fork () and) exec () operations if the executable does not override the EUID or EGID with its own SUID or SGID bits.
Why did my C program fail to set UID and Gid?
My C program, executed as userA, sets uid and gid to userB and creates a file. Not as expected, the file belongs to the group root, because setgid () fails.
Where to find setuid and setgid in Linux permissions?
Similarly, there is a setgid bit which does the same for the gid. To locate the setuid, look for an ‘s’ instead of an ‘x’ in the executable bit of the file permissions. An example of an executable with setuid permission is passwd, as can be seen in the following output.
What happens when the setuid and setgit bits are not set?
This happens when the setuid or setgid bits are set, but the executable bit is not, showing the user an inconsistency: the setuid and setgit bits have no effect if the executable bit is not set. The setuid bit has no effect on directories. Subscribe to our NEWSLETTER and receive latest Linux news, jobs, career advice and tutorials.
Where do I find the setgid bit in Linux?
This is used for file sharing since they can be now modified by all the users who are part of the group of the parent directory. To locate the setgid bit, look for an ‘s’ in the group section of the file permissions, as shown in the example below.