libsodium before ad3004e, in atypical use cases involving certain custom cryptography or untrusted data to crypto_core_ed25519_is_valid_point, mishandles…

libsodium before ad3004e, in atypical use cases involving certain custom cryptography or untrusted data to crypto_core_ed25519_is_valid_point, mishandles checks for whether an elliptic curve point is valid because it sometimes allows points that aren't in the main cryptographic group.