Re: [patch 07/10] unprivileged mounts: add sysctl tunable for "safe" property

["Serge E. Hallyn" <serue@us.ibm.com>]

Quoting Miklos Szeredi (miklos@szeredi.hu):
> > > Maybe sysctls just need to check capabilities, instead of uids.  I
> > > think that would make a lot of sense anyway.
> > 
> > Would it be as simple as tagging the inodes with capability sets?  One
> > set for writing, or one each for reading and writing?
> 
> Yes, or something even simpler, like mapping the owner permission bits
> to CAP_SYS_ADMIN.  There seem to be very few different permissions
> under /proc/sys:
> 
> --w-------
> -r--r--r--
> -rw-------
> -rw-r--r--
> 
> As long as the group and other bits are always the same, and we accept
> that the owner bits really mean CAP_SYS_ADMIN and not something else,

But I would assume some things under /proc/sys/net/ipv4 or
/proc/sys/net/ath0 require CAP_NET_ADMIN rather than CAP_SYS_ADMIN?

> then the permission check would not need to look at uids or gids at
> all.
> 
> Miklos
> -
> To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html