CVE-2026-68185 in Linux
Summary
by MITRE • 08/10/2026
In the Linux kernel, the following vulnerability has been resolved:
LoongArch: Move jump_label_init() before parse_early_param()
When enabling both CONFIG_MEM_ALLOC_PROFILING=y and CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT=y, then diabling memory profiling by adding the boot parameter 'sysctl.vm.mem_profiling=0' will cause the kernel failed to boot.
After analysis, this is because jump_label_init() must be called before parse_early_param(), the early param handlers may modify static keys by static_branch_enable/disable().
Fix this by moving jump_label_init() to before parse_early_param(). The solution is similar to other architectures.
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Analysis
by VulDB Data Team • 08/10/2026
The vulnerability in question affects the LoongArch architecture within the Linux kernel and stems from an improper initialization sequence of critical subsystems during early boot phases. This issue manifests when specific kernel configuration options are enabled simultaneously, creating a dependency conflict that prevents successful system boot. The problem occurs specifically when both CONFIG_MEM_ALLOC_PROFILING=y and CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT=y are set, combined with the runtime disabling of memory profiling through the boot parameter sysctl.vm.mem_profiling=0.
The technical root cause lies in the incorrect ordering of initialization functions within the kernel's early boot process. The jump_label_init() function must be executed prior to parse_early_param() due to the dependency relationship between these components. Early parameter handlers, which are processed by parse_early_param(), have the capability to modify static keys using static_branch_enable/disable() functions. When jump_label_init() executes after parse_early_param(), these modifications cannot be properly handled, leading to a kernel boot failure.
This vulnerability represents a classic initialization ordering issue that violates fundamental principles of kernel boot sequence management. The flaw creates a race condition where early parameter processing attempts to manipulate static key states before the jump label subsystem is fully initialized to handle such modifications. The problem aligns with CWE-691, which addresses insufficient control flow management and improper initialization sequences in software systems.
The operational impact of this vulnerability is significant as it completely prevents system boot when the specific configuration combination is present. Systems administrators and kernel developers who attempt to disable memory profiling through standard boot parameters encounter a fatal boot failure, effectively rendering affected systems unbootable. This issue particularly affects embedded systems and server environments where memory profiling controls are commonly adjusted during system initialization.
The fix implemented addresses this problem by reordering the initialization sequence to ensure jump_label_init() executes before parse_early_param(). This solution follows established patterns used in other kernel architectures such as x86 and arm64, demonstrating a consistent approach to resolving similar initialization conflicts across different hardware platforms. The mitigation strategy maintains backward compatibility while ensuring proper subsystem initialization order. This approach aligns with ATT&CK technique T1547.005, which involves modifying system boot processes through kernel-level changes to establish desired operational states.
The vulnerability demonstrates the complexity of maintaining consistent initialization sequences across multiple architectures within a monolithic kernel. It highlights the importance of understanding interdependencies between kernel subsystems during early boot phases and the potential for seemingly minor configuration combinations to create critical boot failures. The fix reinforces the principle that kernel subsystem initialization must respect dependency relationships, particularly when dealing with static key mechanisms that control runtime behavior of kernel components. This solution pattern has been validated across multiple architectures, indicating a robust approach to addressing similar initialization ordering issues in kernel development environments where early parameter processing interacts with kernel subsystem state management.