CVE-2021-4460
Unknown Unknown - Not Provided
BaseFortify

Publication date: 2025-10-01

Last updated on: 2025-12-10

Assigner: kernel.org

Description
In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Fix UBSAN shift-out-of-bounds warning If get_num_sdma_queues or get_num_xgmi_sdma_queues is 0, we end up doing a shift operation where the number of bits shifted equals number of bits in the operand. This behaviour is undefined. Set num_sdma_queues or num_xgmi_sdma_queues to ULLONG_MAX, if the count is >= number of bits in the operand. Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1472
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2025-10-01
Last Modified
2025-12-10
Generated
2026-06-16
AI Q&A
2025-10-01
EPSS Evaluated
2026-06-15
NVD
CVE-2021-4460
Affected Vendors & Products
Showing 4 associated CPEs
Vendor Product Version / Range
linux linux_kernel to 5.4.118 (exc)
linux linux_kernel From 5.5 (inc) to 5.10.36 (exc)
linux linux_kernel From 5.11 (inc) to 5.11.20 (exc)
linux linux_kernel From 5.12 (inc) to 5.12.3 (exc)
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-125 The product reads data past the end, or before the beginning, of the intended buffer.
Attack-Flow Graph
AI Quick Actions
Instant insights powered by AI
Executive Summary

This vulnerability occurs in the Linux kernel's drm/amdkfd component where a shift operation is performed with a number of bits shifted equal to the number of bits in the operand, which is undefined behavior. Specifically, if get_num_sdma_queues or get_num_xgmi_sdma_queues returns 0, this problematic shift happens. The fix involves setting num_sdma_queues or num_xgmi_sdma_queues to ULLONG_MAX if the count is greater than or equal to the number of bits in the operand to avoid the undefined shift.

Impact Analysis

The vulnerability can cause undefined behavior in the Linux kernel when performing certain shift operations, which may lead to system instability, crashes, or unexpected behavior in the drm/amdkfd component. This could affect systems using AMD kernel drivers related to SDMA queues, potentially impacting system reliability.

Chat Assistant
Ask questions about this CVE
Hi! I’m here to help you understand CVE-2021-4460. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70
EPSS Chart