From: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> > Sent: 22 October 2020 14:51 I've rammed the code into godbolt. https://godbolt.org/z/9v5PPW Definitely a clang bug. Search for [wx]24 in the clang output. nr_segs comes in as w2 and the initial bound checks are done on w2. w24 is loaded from w2 - I don't believe this changes the high bits. There are no references to w24, just x24. So the kmalloc_array() is passed 'huge' and will fail. The iov_iter_init also gets the 64bit value. Note that the gcc code has a sign-extend copy of w2. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
