CVE-2024-43890: tracing: Fix overflow in get_free_elt()

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-08-26 · updated 2026-10-15
Weakness: CWE-190

Description

In the Linux kernel, the following vulnerability has been resolved: tracing: Fix overflow in get_free_elt() "tracing_map->next_elt" in get_free_elt() is at risk of overflowing. Once it overflows, new elements can still be inserted into the tracing_map even though the maximum number of elements (`max_elts`) has been reached. Continuing to insert elements after the overflow could result in the tracing_map containing "tracing_map->max_size" elements, leaving no empty entries. If any attempt is made to insert an element into a full tracing_map using `__tracing_map_insert()`, it will cause an infinite loop with preemption disabled, leading to a CPU hang problem. Fix this by preventing any further increments to "tracing_map->next_elt" once it reaches "tracing_map->max_elt".

Affected products

Linux kernel: from 4.7 before 4.19.320; from 4.20 before 5.4.282; from 5.5 before 5.10.224; from 5.11 before 5.15.165; from 5.16 before 6.1.105; from 6.2 before 6.6.46 — fixed in 4.19.320, 5.10.224, 5.15.165, 5.4.282, 6.1.105, 6.10.5

How to fix

Upgrade to a fixed version: Linux kernel 4.19.320, 5.10.224, 5.15.165, 5.4.282. Check the vendor advisory for mitigations.

References

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