Re: [PATCH net] net: flow_dissector: fail on evil iph->ihl
On 11/01/2013 08:01 AM, Jason Wang wrote: We don't validate iph->ihl which may lead a dead loop if we meet a IPIP skb whose iph->ihl is zero. Fix this by failing immediately when iph->ihl is evil (less than 5). This issue were introduced by commit ec5efe7946280d1e84603389a1030ccec0a767ae (rps: support IPIP encapsulation). Cc: Eric Dumazet Cc: Petr Matousek Cc: Michael S. Tsirkin Cc: Daniel Borkmann Signed-off-by: Jason Wang Sorry, a bit late as I was offline last 4 days, but fwiw: Acked-by: Daniel Borkmann -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH net] net: flow_dissector: fail on evil iph->ihl
On Fri, Nov 01, 2013 at 03:01:10PM +0800, Jason Wang wrote: > We don't validate iph->ihl which may lead a dead loop if we meet a IPIP > skb whose iph->ihl is zero. Fix this by failing immediately when iph->ihl > is evil (less than 5). > > This issue were introduced by commit ec5efe7946280d1e84603389a1030ccec0a767ae > (rps: support IPIP encapsulation). > > Cc: Eric Dumazet > Cc: Petr Matousek > Cc: Michael S. Tsirkin > Cc: Daniel Borkmann > Signed-off-by: Jason Wang Acked-by: Michael S. Tsirkin > --- > This patch is needed for stable. > --- > net/core/flow_dissector.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c > index 8d7d0dd..143b6fd 100644 > --- a/net/core/flow_dissector.c > +++ b/net/core/flow_dissector.c > @@ -40,7 +40,7 @@ again: > struct iphdr _iph; > ip: > iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph); > - if (!iph) > + if (!iph || iph->ihl < 5) > return false; > > if (ip_is_fragment(iph)) > -- > 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH net] net: flow_dissector: fail on evil iph->ihl
From: Jason Wang Date: Fri, 1 Nov 2013 15:01:10 +0800 > We don't validate iph->ihl which may lead a dead loop if we meet a IPIP > skb whose iph->ihl is zero. Fix this by failing immediately when iph->ihl > is evil (less than 5). > > This issue were introduced by commit ec5efe7946280d1e84603389a1030ccec0a767ae > (rps: support IPIP encapsulation). > > Cc: Eric Dumazet > Cc: Petr Matousek > Cc: Michael S. Tsirkin > Cc: Daniel Borkmann > Signed-off-by: Jason Wang Applied and queued up for -stable, thanks Jason. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH net] net: flow_dissector: fail on evil iph->ihl
On Fri, 2013-11-01 at 15:01 +0800, Jason Wang wrote: > We don't validate iph->ihl which may lead a dead loop if we meet a IPIP > skb whose iph->ihl is zero. Fix this by failing immediately when iph->ihl > is evil (less than 5). > > This issue were introduced by commit ec5efe7946280d1e84603389a1030ccec0a767ae > (rps: support IPIP encapsulation). It would be helpful to include the CVE ID here: CVE-2013-4348 Ben. > Cc: Eric Dumazet > Cc: Petr Matousek > Cc: Michael S. Tsirkin > Cc: Daniel Borkmann > Signed-off-by: Jason Wang > --- > This patch is needed for stable. > --- > net/core/flow_dissector.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c > index 8d7d0dd..143b6fd 100644 > --- a/net/core/flow_dissector.c > +++ b/net/core/flow_dissector.c > @@ -40,7 +40,7 @@ again: > struct iphdr _iph; > ip: > iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph); > - if (!iph) > + if (!iph || iph->ihl < 5) > return false; > > if (ip_is_fragment(iph)) -- Ben Hutchings, Staff Engineer, Solarflare Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH net] net: flow_dissector: fail on evil iph->ihl
On Fri, 2013-11-01 at 15:01 +0800, Jason Wang wrote: > We don't validate iph->ihl which may lead a dead loop if we meet a IPIP > skb whose iph->ihl is zero. Fix this by failing immediately when iph->ihl > is evil (less than 5). > > This issue were introduced by commit ec5efe7946280d1e84603389a1030ccec0a767ae > (rps: support IPIP encapsulation). > > Cc: Eric Dumazet > Cc: Petr Matousek > Cc: Michael S. Tsirkin > Cc: Daniel Borkmann > Signed-off-by: Jason Wang > --- > This patch is needed for stable. > --- Acked-by: Eric Dumazet Thanks Jason ! -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH net] net: flow_dissector: fail on evil iph->ihl
We don't validate iph->ihl which may lead a dead loop if we meet a IPIP skb whose iph->ihl is zero. Fix this by failing immediately when iph->ihl is evil (less than 5). This issue were introduced by commit ec5efe7946280d1e84603389a1030ccec0a767ae (rps: support IPIP encapsulation). Cc: Eric Dumazet Cc: Petr Matousek Cc: Michael S. Tsirkin Cc: Daniel Borkmann Signed-off-by: Jason Wang --- This patch is needed for stable. --- net/core/flow_dissector.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 8d7d0dd..143b6fd 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -40,7 +40,7 @@ again: struct iphdr _iph; ip: iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph); - if (!iph) + if (!iph || iph->ihl < 5) return false; if (ip_is_fragment(iph)) -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
