| Message ID | 20120704013258.GA26225@kvack.org |
|---|---|
| State | Rejected, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Benjamin LaHaise <bcrl@kvack.org> Date: Tue, 3 Jul 2012 21:32:58 -0400 > By default, the ppp_generic code initializes the npmode array that filters > incoming packet to accept packets for all protocols. This behaviour is > incorrect, as it results in packets for protocols that an older version > of a PPP implementation may not be aware of to be incorrectly accepted. > This behaviour is visible, for example, when sending IPv6 packets across a > ppp link where pppd has only been configured to use IPv4. > > This change should be safe since pppd will correctly set the protocols it > negotiates to NPMODE_PASS as the appropriate protocols transition to an Up > state. > > Signed-off-by: Benjamin LaHaise <bcrl@kvack.org> As far as I can tell, this has been this way for a very long time. Therefore it is the applications responsibility to adjust the filters to suit their needs and we really can't make such adjustments to this behavior. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index 5c05572..404ac50 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -2619,7 +2619,7 @@ ppp_create_interface(struct net *net, int unit, int *retp) init_ppp_file(&ppp->file, INTERFACE); ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */ for (i = 0; i < NUM_NP; ++i) - ppp->npmode[i] = NPMODE_PASS; + ppp->npmode[i] = NPMODE_DROP; INIT_LIST_HEAD(&ppp->channels); spin_lock_init(&ppp->rlock); spin_lock_init(&ppp->wlock);
By default, the ppp_generic code initializes the npmode array that filters incoming packet to accept packets for all protocols. This behaviour is incorrect, as it results in packets for protocols that an older version of a PPP implementation may not be aware of to be incorrectly accepted. This behaviour is visible, for example, when sending IPv6 packets across a ppp link where pppd has only been configured to use IPv4. This change should be safe since pppd will correctly set the protocols it negotiates to NPMODE_PASS as the appropriate protocols transition to an Up state. Signed-off-by: Benjamin LaHaise <bcrl@kvack.org> --- drivers/net/ppp/ppp_generic.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)