CVE-2026-89748

In the Linux kernel, the following vulnerability has been resolved: tracing: Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. The current !retry test reverses both outcomes. It returns an error after a successful final replacement, leaving the link update complete but the reader bookkeeping unfinished. After a failed final replacement, it falls through and updates the head and reader pointers as though the replacement succeeded, which can corrupt the ring. Treat only a negative counter as exhaustion and return the documented -EBUSY error.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/df02489aa3aa1834659f0d20c89f7d212047d268
https://git.kernel.org/stable/c/e0d3aed7b12cf37b74c7cc5265073d0263b49cde

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 20:20

Updated : 2026-09-13 07:17

NVD link : CVE-2026-89748

Mitre link : CVE-2026-89748

CVE.ORG link : CVE-2026-89748

JSON object : View

Products Affected

No product.

CWE

No CWE.

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