On 06/15/2016 08:39 AM, Pablo Neira Ayuso wrote: > But nlmsg_len should match len in this. > > If we're just sending a part of the packet to userspace, then we > should adjust nlmsg_len to indicate exactly the netlink message length > that we're sending to userspace. > > Is your patch triggering this nlmsg_len != len?
The value of len here is how many bytes were returned by recv. We do send the entire nlmsg_len to userspace, but recv cannot copy the full packet because the buffer is not big enough to hold this. They only allocate the buffer assuming that the packet won't be bigger than their snap len, but we send more data than their snap len and they don't handle this condition well.
