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  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Wed, 31 Jan 2007 12:52:46 -0800 (PST)
From:	David Miller <davem@...emloft.net>
To:	baruch@...en.org
Cc:	netdev@...r.kernel.org
Subject: Re: [PATCH 3/3] Check num sacks in SACK fast path

From: Baruch Even <baruch@...en.org>
Date: Mon, 29 Jan 2007 09:13:49 +0200

> When we check for SACK fast path make sure that we also have the same number of
> SACK blocks in the cache and in the new SACK data. This prevents us from
> mistakenly taking the cache data if the old data in the SACK cache is the same
> as the data in the SACK block.
> 
> Signed-Off-By: Baruch Even <baruch@...en.org>

We could implement this without extra state, for example by
clearing out the rest of the recv_sack_cache entries.

We should never see a SACK block from sequence zero to zero,
which would be an empty SACK block.

Something like the following?

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index c26076f..84cd722 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -999,6 +1001,10 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_
 				return 0;
 		}
 	}
+	for (; i <= 4; i++) {
+		tp->recv_sack_cache[i].start_seq = 0;
+		tp->recv_sack_cache[i].end_seq = 0;
+	}
 
 	if (flag)
 		num_sacks = 1;
-
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