From: Baruch Even Date: Thu, 25 Jan 2007 21:35:06 +0000 (-0800) Subject: [TCP]: Fix sorting of SACK blocks. X-Git-Tag: v2.6.20-rc7~56^2~7 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=db3ccdac261e015023cfd922840170f14c9cdc09;p=linux-2.6 [TCP]: Fix sorting of SACK blocks. The sorting of SACK blocks actually munges them rather than sort, causing the TCP stack to ignore some SACK information and breaking the assumption of ordered SACK blocks after sorting. The sort takes the data from a second buffer which isn't moved causing subsequent data moves to occur from the wrong location. The fix is to use a temporary buffer as a normal sort does. Signed-off-By: Baruch Even Signed-off-by: David S. Miller --- diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 5c16e24a60..c26076fb89 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1011,10 +1011,11 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ for (j = 0; j < i; j++){ if (after(ntohl(sp[j].start_seq), ntohl(sp[j+1].start_seq))){ - sp[j].start_seq = htonl(tp->recv_sack_cache[j+1].start_seq); - sp[j].end_seq = htonl(tp->recv_sack_cache[j+1].end_seq); - sp[j+1].start_seq = htonl(tp->recv_sack_cache[j].start_seq); - sp[j+1].end_seq = htonl(tp->recv_sack_cache[j].end_seq); + struct tcp_sack_block_wire tmp; + + tmp = sp[j]; + sp[j] = sp[j+1]; + sp[j+1] = tmp; } }