Re: Fchown on unix domain sockets?

From: David Wagner
Date: Tue Nov 02 2004 - 00:31:21 EST


Jan Engelhardt wrote:
>How about setting the permissions beforehand?

This makes you susceptible to TOCTTOU (race condition) attacks in some
cases. Often, the only way to change ownership or permissions of a file
you want to operate on securely is to use fchown()/fchmod() etc.

It came as a surprise to me that open() + fchown()/fchmod() does not
work in some cases that chown()/chmod() do. I wonder whether this has
any effect on applications. Could this result in security holes in
applications that are unaware of this property?
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/