Looking at __sys_setsockopt() I noticed that the BPF intercept can also cause set_fs(KERNEL_DS) be set in order to pass a modified buffer into the actual setsockopt() code. If that functionality is to be kept then the underlying protocol specific code needs changing to accept a kernel buffer. The 32bit compat code would also be a lot simpler if it could pass an kernel buffer through. At the moment it copies the modified buffer back out onto the user stack. I'm sure there have been suggestions to remove that complete hack. Fixing the compat code would leave a kernel_[sg]et_sockopt() that still worked. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
