CVE-2022-48713 in Linux
Summary
by MITRE • 06/20/2024
In the Linux kernel, the following vulnerability has been resolved:
perf/x86/intel/pt: Fix crash with stop filters in single-range mode
Add a check for !buf->single before calling pt_buffer_region_size in a place where a missing check can cause a kernel crash.
Fixes a bug introduced by commit 670638477aed ("perf/x86/intel/pt: Opportunistically use single range output mode"), which added a support for PT single-range output mode. Since that commit if a PT stop filter range is hit while tracing, the kernel will crash because of a null pointer dereference in pt_handle_status due to calling pt_buffer_region_size without a ToPA configured.
The commit which introduced single-range mode guarded almost all uses of the ToPA buffer variables with checks of the buf->single variable, but missed the case where tracing was stopped by the PT hardware, which happens when execution hits a configured stop filter.
Tested that hitting a stop filter while PT recording successfully records a trace with this patch but crashes without this patch.
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Analysis
by VulDB Data Team • 09/17/2025
The vulnerability described in CVE-2022-48713 represents a critical kernel-level issue within the Linux perf subsystem that specifically affects Intel Processor Trace functionality. This flaw manifests as a kernel crash occurring when perf attempts to handle stop filters in single-range mode, demonstrating a fundamental race condition in the processor trace buffer management system. The vulnerability directly impacts systems utilizing Intel's hardware performance monitoring capabilities, particularly those employing the perf tool for tracing and profiling operations.
The technical root cause stems from an incomplete implementation of the single-range output mode feature introduced in commit 670638477aed. While the original implementation properly safeguarded most accesses to ToPA (Trace Output Page Array) buffer variables through checks against the buf->single flag, a critical oversight occurred in the pt_handle_status function where pt_buffer_region_size is invoked without proper validation. This missing check creates a null pointer dereference scenario when the processor trace hardware triggers a stop filter during active tracing, causing immediate system instability.
The operational impact of this vulnerability extends beyond simple kernel crashes to potentially compromise system availability and stability during performance analysis operations. When a stop filter is triggered while in single-range mode, the kernel's inability to properly handle the buffer state results in immediate system termination, making this particularly dangerous in production environments where continuous monitoring is required. The vulnerability affects systems running Linux kernels that include the specific commit mentioned, rendering them susceptible to denial of service conditions during normal perf operations.
Mitigation strategies for this vulnerability require immediate patch application to address the missing buffer validation check before the pt_buffer_region_size function call. System administrators should prioritize updating their kernel versions to include the fix that properly implements the !buf->single check before buffer region size operations. Additionally, organizations should consider temporarily disabling perf tracing operations involving stop filters until the patch is applied, as a defensive measure to prevent exploitation. This vulnerability aligns with CWE-476 which addresses null pointer dereference conditions, and represents a specific implementation gap that could be categorized under ATT&CK technique T1547.001 for privilege escalation through kernel exploitation, though the immediate impact is primarily denial of service rather than lateral movement.