Message ID | 1274072629.2299.58.camel@edumazet-laptop |
---|---|
State | Superseded, archived |
Delegated to: | David Miller |
Headers | show |
On Mon, 17 May 2010 07:03:49 +0200 Eric Dumazet <eric.dumazet@gmail.com> wrote: > Le lundi 17 mai 2010 à 03:49 +0000, Bijay Singh a écrit : > > > I am on quite an old kernel 2.6.27 and could not apply your patches. > > > > Then i moved on to the kernel 2.6.32.11 however since then I have not been able to bring up my card, this is something i need to fix before i can test you fix. Working on that. > > > > Thanks again for the status report. > > I see bug is older than what I stated in my previous mail > > I could reproduce it in my lab and confirm following patch fixes it > > This is a stable candidate (2.6.27 kernels) > > Thanks > > [PATCH] tcp: tcp_synack_options() fix > > Commit 33ad798c924b4a (tcp: options clean up) introduced a problem > if MD5+SACK+timestamps were used in initial SYN message. > > Some stacks (old linux for example) try to negotiate MD5+SACK+TSTAMP > sessions, but since 20 bytes of tcp options space are not enough to > store all the bits needed, we chose to disable timestamps in this case. > > We send a SYN-ACK _without_ timestamp option, but socket has timestamps > enabled and all further outgoing messages contain a TS block, all with > the initial timestamp of the remote peer. > > Fix is to really disable timestamps option for the whole session. > > Reported-by: Bijay Singh <Bijay.Singh@guavus.com> > Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> > --- > net/ipv4/tcp_output.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c > index 0dda86e..b8bb226 100644 > --- a/net/ipv4/tcp_output.c > +++ b/net/ipv4/tcp_output.c > @@ -667,7 +667,7 @@ static unsigned tcp_synack_options(struct sock *sk, > u8 cookie_plus = (xvp != NULL && !xvp->cookie_out_never) ? > xvp->cookie_plus : > 0; > - bool doing_ts = ireq->tstamp_ok; > + bool doing_ts; > > #ifdef CONFIG_TCP_MD5SIG > *md5 = tcp_rsk(req)->af_specific->md5_lookup(sk, req); > @@ -680,11 +680,12 @@ static unsigned tcp_synack_options(struct sock *sk, > * rather than TS in order to fit in better with old, > * buggy kernels, but that was deemed to be unnecessary. > */ > - doing_ts &= !ireq->sack_ok; > + ireq->tstamp_ok &= !ireq->sack_ok; > } > #else > *md5 = NULL; > #endif > + doing_ts = ireq->tstamp_ok; > > /* We always send an MSS option. */ > opts->mss = mss; > > Make this gets back to stable as well.
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 0dda86e..b8bb226 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -667,7 +667,7 @@ static unsigned tcp_synack_options(struct sock *sk, u8 cookie_plus = (xvp != NULL && !xvp->cookie_out_never) ? xvp->cookie_plus : 0; - bool doing_ts = ireq->tstamp_ok; + bool doing_ts; #ifdef CONFIG_TCP_MD5SIG *md5 = tcp_rsk(req)->af_specific->md5_lookup(sk, req); @@ -680,11 +680,12 @@ static unsigned tcp_synack_options(struct sock *sk, * rather than TS in order to fit in better with old, * buggy kernels, but that was deemed to be unnecessary. */ - doing_ts &= !ireq->sack_ok; + ireq->tstamp_ok &= !ireq->sack_ok; } #else *md5 = NULL; #endif + doing_ts = ireq->tstamp_ok; /* We always send an MSS option. */ opts->mss = mss;