Bug 2451230 (CVE-2026-23309)

Summary: CVE-2026-23309 kernel: tracing: Add NULL pointer check to trigger_data_free()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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Version: unspecifiedKeywords: Security
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OS: Linux   
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A flaw was found in the Linux kernel. When the 'trigger_data_alloc()' function fails to allocate memory and returns a null pointer, the subsequent 'trigger_data_free()' function attempts to access this null pointer. This null pointer dereference can lead to a system crash, resulting in a Denial of Service (DoS) for the affected system.
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Description OSIDB Bzimport 2026-03-25 11:05:57 UTC 
In the Linux kernel, the following vulnerability has been resolved:

tracing: Add NULL pointer check to trigger_data_free()

If trigger_data_alloc() fails and returns NULL, event_hist_trigger_parse()
jumps to the out_free error path. While kfree() safely handles a NULL
pointer, trigger_data_free() does not. This causes a NULL pointer
dereference in trigger_data_free() when evaluating
data->cmd_ops->set_filter.

Fix the problem by adding a NULL pointer check to trigger_data_free().

The problem was found by an experimental code review agent based on
gemini-3.1-pro while reviewing backports into v6.18.y.
Comment 1 Alexander B 2026-03-25 14:34:35 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026032528-CVE-2026-23309-4243@gregkh/T