Well, this is a tricky question!
The traditional meat for kebab is lamb, but kebab can also be made with pork, beef or other meat.
Pork should be thoroughly tested before it is given to the dog. Pigs eat anything: insects, worms, flesh of dead animals including other pigs and garbage. Because of this parasite infestations can be carried from pigs. Also, pigs do not sweat, so they do not eliminate built up toxins.
A lot depends on how old is your dog (pork is not recommended for baby dogs), then a lot depends on the heat treatment (better not give your dog raw pork meat).
Kebabs can have an extremely high salt content so if you are buying kebabs it is important to make sure that salt content is not too high.
Also, you should know that there is nearly 2000 calories per kebab serving, which exceeds the daily amount of calories for average dog!
Kebab made with lamb, beef or chicken meat is more safe to give your dog, but still be careful with salt and calories!
Most important of all, make sure that there is no onions with kebab, because onions can harm or even kill your dog!