Memory safety using cryptographic entropy tagging

A method comprising:

• decrypting content of a memory location referenced by a pointer used in an attempted access to the memory location, the pointer including a supplied tag value, wherein the supplied tag value is one of a plurality of possible tag values and wherein the decrypting is performed based on the supplied tag value;
• measuring entropy of at least one of a plurality of decryption results;
• and
• determining whether the attempted access is valid by comparing the entropy of a result of the decrypting to the entropy of a result of decrypting based on at least an other one of the plurality of possible tag values or a threshold value.

A non-transitory machine-readable medium storing instructions which, when executed by a machine, causes the machine to perform a method comprising:

• decrypting content of a memory location referenced by a pointer used in an attempted access to the memory location, the pointer including a supplied tag value, wherein the supplied tag value is one of a plurality of possible tag values and wherein the decrypting is performed based on the supplied tag value;
• measuring entropy of at least one of a plurality of decryption results;
• and
• determining whether the attempted access is valid by comparing the entropy of a result of the decrypting to the entropy of a result of decrypting based on at least an other one of the plurality of possible tag values or a threshold value.