mount option suid

[Network Servers]

What does this option do? Is there documentation on it somewhere? Are there any security concerns around this option?

[Tom Geudens]

Hi,
There's info in
#man 1m mount_vxfs

The way I understand it, you are not allowed to execute suid-scripts (present in that particular filesystem) if the "nosuid" option is used in mounting the filesystem. This would make sense for filesystems that are not "local" to the system (NFS-mounted for example).

Regards,
Tom

[U.SivaKumar_2]

Hi,

nosuid option is mainly for NFS security which
prohibits running any program with setuid in
NFS mount directory which if malicious can cause system to come to heels.

By default , suid is set for mounted filesysem

regards,
U.SivaKumar

[Wodisch]

Hi,

I would not restrict that option ("nosuid" actually!) to only "NFS" mounted filesystems, but to ALL filesystems, which are not under your complete control concerning codefiles/executables/scripts:
- temporary files
- data files
- databases
- file server files
- text/document files
- removable filesystems (floppies, MOs)

And mounting all those filesystems with "nosuid" just keeps everybody from createing (actually: from executing) SUID-programs, i.e. to start a program not under the UID of the starter but the owner of the file.
You'll only need the option "suid" for your root-filesystem, "/usr", and "opt", and possibly for a filesystem containing application codefiles/-scipts.

FWIW,
Wodisch