Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

crypto: atmel-ecc - reject hardware ECDH without a public key

The hardware ECDH path in atmel_ecdh_compute_shared_secret() uses the private key stored in the device. However, the public key is cached only after atmel_ecdh_set_secret() successfully generated that private key for the current tfm.

atmel_ecdh_generate_public_key() already rejects requests when no public key is cached. Add the same check to atmel_ecdh_compute_shared_secret() to prevent the device from using a private key that was not generated for the current tfm.