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  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Tue, 6 Oct 2015 12:26:53 -0700
From:	Alexei Starovoitov <>
To:	Eric Dumazet <>
Cc:	Daniel Borkmann <>,
	Ingo Molnar <>,
	"David S. Miller" <>,
	Andy Lutomirski <>,
	Hannes Frederic Sowa <>,
	Eric Dumazet <>,
	Kees Cook <>,,,
Subject: Re: [PATCH net-next 1/2] bpf: enable non-root eBPF programs

On 10/6/15 10:56 AM, Eric Dumazet wrote:
> On Tue, 2015-10-06 at 10:50 -0700, Alexei Starovoitov wrote:
>> was also thinking that we can do it only in paths that actually
>> have multiple protocol layers, since today bpf is mainly used with
>> tcpdump(raw_socket) and new af_packet fanout both have cb cleared
>> on RX, because it just came out of alloc_skb and no layers were called,
>> and on TX we can clear 20 bytes in dev_queue_xmit_nit().
>> af_unix/netlink also have clean skb. Need to analyze tun and sctp...
>> but it feels overly fragile to save a branch in sk_filter,
>> so planning to go with
>> if(unlikely(prog->cb_access)) memset in sk_filter().
> This will break TCP use of sk_filter().
> skb->cb[] contains useful data in TCP layer.

oops. thanks for catching. In case of sk_filter on top of tcp sock,
it shouldn't be looking at cb at all.
I'm thinking to send a patch to get rid of cb access for socket filters
all together until better solution found.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

Powered by blists - more mailing lists