From: Christoph Hellwig > Sent: 20 July 2020 13:47 > > setsockopt is the last place in architecture-independ code that still > uses set_fs to force the uaccess routines to operate on kernel pointers. > > This series adds a new sockptr_t type that can contained either a kernel > or user pointer, and which has accessors that do the right thing, and > then uses it for setsockopt, starting by refactoring some low-level > helpers and moving them over to it before finally doing the main > setsockopt method. Another 'gotcha' ... On an least some architectures (possibly only m68k) IIRC all structures are actually passed by reference. (This used to be true for sparc - but it may have changed in the last 30 years.) David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)