Why SGID needs the file executable for group to be effective? (not the same as SUID)
I am learning about permissions in Linux recently and countered a confused problem about SUID and SGID.
As far as I know, when the SUID is set in the owner permissions, and the file is executable, processes which run it will have effective user id base on user who owns the file. For the SGID, it behaves the same way as SUID (executable files), except the group is affected instead.
But when I tried this:
As you can see, the "ls" program show two uppercase "S" since the owner and group both can't execute "show_resugid". But why the effective user id changed and the effective group id didn't?
I searched with Google and failed to find the answer. Can you tell me where to find the corresponding manual/doc or teach me about it?
permissions
asked 1 hour ago
frankunderwood
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I am learning about permissions in Linux recently and countered a confused problem about SUID and SGID.
As far as I know, when the SUID is set in the owner permissions, and the file is executable, processes which run it will have effective user id base on user who owns the file. For the SGID, it behaves the same way as SUID (executable files), except the group is affected instead.
But when I tried this:
As you can see, the "ls" program show two uppercase "S" since the owner and group both can't execute "show_resugid". But why the effective user id changed and the effective group id didn't?
I searched with Google and failed to find the answer. Can you tell me where to find the corresponding manual/doc or teach me about it?
permissions
asked 1 hour ago
frankunderwood
1
New contributor
frankunderwood is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
I am learning about permissions in Linux recently and countered a confused problem about SUID and SGID.
As far as I know, when the SUID is set in the owner permissions, and the file is executable, processes which run it will have effective user id base on user who owns the file. For the SGID, it behaves the same way as SUID (executable files), except the group is affected instead.
But when I tried this:
As you can see, the "ls" program show two uppercase "S" since the owner and group both can't execute "show_resugid". But why the effective user id changed and the effective group id didn't?
I searched with Google and failed to find the answer. Can you tell me where to find the corresponding manual/doc or teach me about it?
permissions
asked 1 hour ago
frankunderwood
1
New contributor
frankunderwood is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I am learning about permissions in Linux recently and countered a confused problem about SUID and SGID.
As far as I know, when the SUID is set in the owner permissions, and the file is executable, processes which run it will have effective user id base on user who owns the file. For the SGID, it behaves the same way as SUID (executable files), except the group is affected instead.
But when I tried this:
As you can see, the "ls" program show two uppercase "S" since the owner and group both can't execute "show_resugid". But why the effective user id changed and the effective group id didn't?
I searched with Google and failed to find the answer. Can you tell me where to find the corresponding manual/doc or teach me about it?
permissions
permissions
asked 1 hour ago
frankunderwood
1
New contributor
frankunderwood is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 1 hour ago
frankunderwood
1
New contributor
frankunderwood is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 1 hour ago
frankunderwood
1
New contributor
frankunderwood is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 1 hour ago
frankunderwood
1
asked 1 hour ago
frankunderwood
1
1
New contributor
frankunderwood is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
frankunderwood is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
frankunderwood is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
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