scsi: bsg: fix buffer overflow in scsi_bsg_uring_cmd()

scsi: bsg: fix buffer overflow in scsi_bsg_uring_cmd()

The bounds checking in scsi_bsg_uring_cmd() does not work because
cmd->request_len is a u32 and scmd->cmd_len is a u16.  We check that
scmd->cmd_len is valid but if the cmd->request_len is more than
USHRT_MAX it would still lead to a buffer overflow when we do the
copy_from_user().

Fixes: 7b6d3255e7f8 ("scsi: bsg: add io_uring passthrough handler")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Link: https://patch.msgid.link/adjNnMYK7A7KMNkA@stanley.mountain
Signed-off-by: Jens Axboe <axboe@kernel.dk>