On Tue, 16 Oct 2018, Dmitry Torokhov wrote: > On Thu, Sep 27, 2018 at 07:35:37AM -0700, Matthew Wilcox wrote: > > On Mon, Sep 24, 2018 at 11:41:58AM -0700, Dmitry Torokhov wrote: > > > > How large is the allocation? AFACIT nRequests larger than KMALLOC_MAX_SIZE > > > > are larger than the maximum allowed by the page allocator. Thus the warning > > > > and the NULL return. > > > > > > The size in this particular case is being derived from a value passed > > > from userspace. Input core does not care about any limits on size of > > > memory kmalloc() can support and is perfectly happy with getting NULL > > > and telling userspace to go away with their silly requests by returning > > > -ENOMEM. > > > > > > For the record: I definitely do not want to pre-sanitize size neither in > > > uinput nor in input core. > > > > Probably should be using kvzalloc then. > > No. No sane input device can track so many contacts so we need to use > kvzalloc(). Failing to allocate memory is proper response here. What is a "contact" here? Are we talking about SG segments?
