netdev - Re: [PATCH] net: Fix security_socket

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 22 Jul 2011 08:22:24 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	penguin-kernel@...ove.SAKURA.ne.jp
Cc:	casey@...aufler-ca.com, anton@...ba.org, netdev@...r.kernel.org,
	linux-security-module@...r.kernel.org
Subject: Re: [PATCH] net: Fix security_socket_sendmsg() bypass problem.

From: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
Date: Sat, 23 Jul 2011 00:12:53 +0900

> I think the regression for SMACK can be fixed with below patch.
> 
> Should I pass nosec flags down to "struct security_operations"->sendmsg()
> so that SELinux checks sock_has_perm() for only once when multiple different
> destination's addresses are passed to sendmmsg()?
> 
> static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
> 				  int size, int nosec)
> {
> 	return nosec ? 0 : sock_has_perm(current, sock->sk, SOCKET__WRITE);
> }

Ugh, this takes away a non-trivial part of the performance gain of
sendmmsg().

I would instead rather that you check ahead of time whether this
actually is a send to different addresses.  If they are all the
same, keep the nosec code path.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html