[PATCH RFCv2 0/4] Etnaviv DRM driver again

[Lucas Stach]

Am Donnerstag, den 22.10.2015, 09:12 +0200 schrieb Daniel Vetter:
[...]

> > > - all the array allocations aren't checked for integer overflows in
> > >   gem_submit. Just use kmalloc_array or similar to get this right. That
> > >   means you need to allocations in submit_create, but imo better safe than
> > >   security-buggy. Similar problem in submit_reloc, but there
> > >   copy_from_user will protect you since you only copy individual structs.
> > >   Still a bit fragile.
> > 
> > I'm not sure kmalloc_array() is the right answer there, but I'll look
> > into it - I'd really like to avoid doing lots of small kmalloc()s all
> > over the place as each one has a non-zero cost.  The more we can lump
> > together, the better - but it has to be done safely.
> 
> That was just my preference since I have a hard time reasonining about
> overflow checks so like to avoid them.
> 
We might just get some reasonable limits on the number of allowed
objects per submit in place, like 64k buffers and relocs should be
enough for everyone. *famous last words*

Regards,
Lucas

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