hw: amd: arbitrary code execution in bios due to a fault in communication buffer

Failure to validate the communication buffer and communication service in the BIOS may allow an attacker to tamper with the buffer resulting in potential SMM (System Management Mode) arbitrary code execution.

Insufficient bounds checking in ASP (AMD Secure Processor) may allow for an out of bounds read in SMI (System Management Interface) mailbox checksum calculation triggering a data abort, resulting in a potential denial of service.

Time-of-check Time-of-use (TOCTOU) in the BIOS2PSP command may allow an attacker with a malicious BIOS to create a race condition causing the ASP bootloader to perform out-of-bounds SRAM reads upon an S3 resume event potentially leading to a denial of service.

Failure to validate the length fields of the ASP (AMD Secure Processor) sensor fusion hub headers may allow an attacker with a malicious Uapp or ABL to map the ASP sensor fusion hub region and overwrite data structures leading to a potential loss of confidentiality and integrity.

Insufficient bounds checking in ASP (AMD Secure Processor) may allow for an out of bounds read in SMI (System Management Interface) mailbox checksum calculation triggering a data abort, resulting in a potential denial of service.

Improper syscall input validation in AMD TEE (Trusted Execution Environment) may allow an attacker with physical access and control of a Uapp that runs under the bootloader to reveal the contents of the ASP (AMD Secure Processor) bootloader accessible memory to a serial port, resulting in a potential loss of integrity.

Speculative Leaks

A division-by-zero error on some AMD processors can potentially return speculative data resulting in loss of confidentiality. 

Insufficient input validation in the ASP (AMD Secure Processor) bootloader may allow an attacker with a compromised Uapp or ABL to coerce the bootloader into exposing sensitive information to the SMU (System Management Unit) resulting in a potential loss of confidentiality and integrity.

hw: cpu: LFENCE/JMP Mitigation Update for CVE-2017-5715

LFENCE/JMP (mitigation V2-2) may not sufficiently mitigate CVE-2017-5715 on some AMD CPUs.

hw: cpu: AMD CPUs may transiently execute beyond unconditional direct branch

Some AMD CPUs may transiently execute beyond unconditional direct branches, which may potentially result in data leakage.