Re: [PATCH] net: small bug on rxhash calculation

From: Eric Dumazet <redacted>
Date: Sat, 08 Sep 2012 10:18:40 +0200

On Fri, 2012-09-07 at 16:40 -0700, Chema Gonzalez wrote:

quoted

In the current rxhash calculation function, while the
sorting of the ports/addrs is coherent (you get the
same rxhash for packets sharing the same 4-tuple, in
both directions), ports and addrs are sorted
independently. This implies packets from a connection
between the same addresses but crossed ports hash to
the same rxhash.

For example, traffic between A=S:l and B=L:s is hashed
(in both directions) from {L, S, {s, l}}. The same
rxhash is obtained for packets between C=S:s and D=L:l.

This patch ensures that you either swap both addrs and ports,
or you swap none. Traffic between A and B, and traffic
between C and D, get their rxhash from different sources
({L, S, {l, s}} for A<->B, and {L, S, {s, l}} for C<->D)

The patch is co-written with Eric Dumazet [off-list ref]

Signed-off-by: Chema Gonzalez <redacted>
---

Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied and queued up for -stable, thanks.