I am not 100% sure that his is what it is, I couldn't find anything else that looked close, so I plumped for this one - but listen to this quote (it refers to a similar looking caterpillar, and mine was also on a rose bush):
"The looper type larvae feed on rose species and overwinter as pupae in the soil. Since many caterpillars go through several different moults, they can look different as they stage through to maturity. This link at the habitas.org.uk website shows two different colour forms of the Shoulder Stripe larvae.
So, the best that can be said about the 25mm long caterpillar image shown here is that it is representative of what an immature Shoulder Stripe larva might look like. - At least it was feeding on garden rose and the moths do frequent the garden! "
quote from here - Moths
-----------------
Bookmarks