Commits
Pavel Begunkov committed f246eedbafd
io_uring: fix dead-hung for non-iter fixed rw commit 311ae9e159d81a1ec1cf645daf40b39ae5a0bd84 upstream. Read/write requests to devices without implemented read/write_iter using fixed buffers can cause general protection fault, which totally hangs a machine. io_import_fixed() initialises iov_iter with bvec, but loop_rw_iter() accesses it as iovec, dereferencing random address. kmap() page by page in this case Cc: stable@vger.kernel.org Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>