Vulnerabilities > CVE-2024-26721 - Incorrect Calculation of Buffer Size vulnerability in Linux Kernel

047910
CVSS 5.5 - MEDIUM
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
LOW
Confidentiality impact
NONE
Integrity impact
NONE
Availability impact
HIGH
local
low complexity
linux
CWE-131

Summary

In the Linux kernel, the following vulnerability has been resolved: drm/i915/dsc: Fix the macro that calculates DSCC_/DSCA_ PPS reg address Commit bd077259d0a9 ("drm/i915/vdsc: Add function to read any PPS register") defines a new macro to calculate the DSC PPS register addresses with PPS number as an input. This macro correctly calculates the addresses till PPS 11 since the addresses increment by 4. So in that case the following macro works correctly to give correct register address: _MMIO(_DSCA_PPS_0 + (pps) * 4) However after PPS 11, the register address for PPS 12 increments by 12 because of RC Buffer memory allocation in between. Because of this discontinuity in the address space, the macro calculates wrong addresses for PPS 12 - 16 resulting into incorrect DSC PPS parameter value read/writes causing DSC corruption. This fixes it by correcting this macro to add the offset of 12 for PPS >=12. v3: Add correct paranthesis for pps argument (Jani Nikula) (cherry picked from commit 6074be620c31dc2ae11af96a1a5ea95580976fb5)

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Overflow Buffers
    Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
  • Buffer Overflow via Parameter Expansion
    In this attack, the target software is given input that the attacker knows will be modified and expanded in size during processing. This attack relies on the target software failing to anticipate that the expanded data may exceed some internal limit, thereby creating a buffer overflow.