[PATCH net 3/3] net: sched: ife: check on metadata length
This patch checks if sk buffer is available to dererence ife header. If not then NULL will returned to signal an malformed ife packet. This avoids to crashing the kernel from outside. Signed-off-by: Alexander Aring --- net/ife/ife.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/ife/ife.c b/net/ife/ife.c index 8632d2685efb..7c100034fbee 100644 --- a/net/ife/ife.c +++ b/net/ife/ife.c @@ -70,6 +70,9 @@ void *ife_decode(struct sk_buff *skb, u16 *metalen) u16 ifehdrln; ifehdr = (struct ifeheadr *) (skb->data + skb->dev->hard_header_len); + if (skb->len < skb->dev->hard_header_len + IFE_METAHDRLEN) + return NULL; + ifehdrln = ntohs(ifehdr->metalen); total_pull = skb->dev->hard_header_len + ifehdrln; -- 2.11.0
Re: [PATCH net 3/3] net: sched: ife: check on metadata length
On Thu, Apr 19, 2018 at 12:35 AM, Alexander Aring wrote: > This patch checks if sk buffer is available to dererence ife header. If > not then NULL will returned to signal an malformed ife packet. This > avoids to crashing the kernel from outside. > > Signed-off-by: Alexander Aring Reviewed-by: Yotam Gigi > --- > net/ife/ife.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/net/ife/ife.c b/net/ife/ife.c > index 8632d2685efb..7c100034fbee 100644 > --- a/net/ife/ife.c > +++ b/net/ife/ife.c > @@ -70,6 +70,9 @@ void *ife_decode(struct sk_buff *skb, u16 *metalen) > u16 ifehdrln; > > ifehdr = (struct ifeheadr *) (skb->data + skb->dev->hard_header_len); > + if (skb->len < skb->dev->hard_header_len + IFE_METAHDRLEN) > + return NULL; > + > ifehdrln = ntohs(ifehdr->metalen); > total_pull = skb->dev->hard_header_len + ifehdrln; > > -- > 2.11.0 >
Re: [PATCH net 3/3] net: sched: ife: check on metadata length
On 19/04/18 01:37 AM, yotam gigi wrote: On Thu, Apr 19, 2018 at 12:35 AM, Alexander Aring wrote: This patch checks if sk buffer is available to dererence ife header. If not then NULL will returned to signal an malformed ife packet. This avoids to crashing the kernel from outside. Signed-off-by: Alexander Aring Reviewed-by: Yotam Gigi Acked-by: Jamal Hadi Salim cheers, jamal
