I have never heard that a dog could digest a sock. I'm not sure they can poop the whole thing out either, I know they can throw it up. Maybe call an emergency vet and see what they say?
Misty- Samoyed Mix, Tannor- Golden Retriever CGC
Robyn- GSD CGC, TC, Midnite-GSD CGC,TC, Brennan-Golden Retriever CGC, Batman-Husky/Greyhound , Apollo-GSD