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
| ||
|
Date: Wed, 07 May 2008 14:20:13 -0700 (PDT) From: David Miller <davem@...emloft.net> To: hkchu@...gle.com Cc: netdev@...r.kernel.org Subject: Re: Socket buffer sizes with autotuning From: "Jerry Chu" <hkchu@...gle.com> Date: Wed, 7 May 2008 11:54:01 -0700 > This is one of many things about skb that I still don't completely understand. > Why in tcp_transmit_skb() we'll have to pskb_copy() if skb_cloned()? The other clone holder owns the packet header area. All packets on the retransmit queue of TCP are headerless. The call sites down into the device add the headers. Therefore we cannot have two paths modifying the headers at the same time. > Can't we clone a skb mulitple times? Is it due to some special optimization > from skb->fclone stuff... that imposes this restriction? No, it has nothing to do with fclone. It has to do with what instance owns the packet header area in front of the user's TCP data. -- 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
Powered by blists - more mailing lists