Comment 4 for bug 1794766

Bionic already has commit 639812a1ed9b since it was added to mainline as of v4.14-rc6:

639812a1ed9b nbd: don't set the device size until we're connected

Can you confirm Bionic has this bug after applying all the latest updates? If it does, we can perform a "Reverse" bisect, since you confirm this bug is fixed in 4.19-rc5.