Messages in this thread | | | Date | Wed, 06 Jan 2010 16:18:52 -0500 | From | William Allen Simpson <> | Subject | [PATCH 0/2] net: replace buggy tcp_optlen, and cleanup |
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This bugginess was reported in October, November, December, and January. I'm requesting some independent review and testing.
The tcp_optlen() function returns a potential *negative* unsigned:
-static inline unsigned int tcp_optlen(const struct sk_buff *skb) -{ - return (tcp_hdr(skb)->doff - 5) * 4; -} -
This is replaced by tcp_header_len_th() and tcp_option_len_th().
The tcp_optlen() function is used *only* in two drivers, that also have rather messy coding practices; such as:
- if ((mss = skb_shinfo(skb)->gso_size)) { ... - } else - mss = 0;
Or:
- mss = 0; - if ((mss = skb_shinfo(skb)->gso_size) != 0) {
Or:
- iph->tot_len = htons(mss + ip_tcp_len + tcp_opt_len); - hdrlen = ip_tcp_len + tcp_opt_len;
Or mixing word and byte sized variables, without using defined constants or useful sizeof() to make the code self-documenting:
- if (tcp_opt_len || (iph->ihl > 5)) { - vlan_tag_flags |= ((iph->ihl - 5) + - (tcp_opt_len >> 2)) << 8; - }
Stand-alone patch, originally developed for TCPCT.
Signed-off-by: William.Allen.Simpson@gmail.com
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