Linux Kernel CVE-2026-45993

The LoongArch architecture syscall dispatch path in the Linux kernel uses a function pointer table indexed directly by a user-controlled syscall number. The missing array_index_nospec() macro - the standard Linux kernel mitigation for Spectre variant 1 (CVE-2017-5753, bounds check bypass) - means the CPU can speculatively dereference beyond the end of the syscall table before the hardware resolves the bounds check. The array_index_nospec() primitive uses a bitmask-based index clamp that forces the speculative path to a safe in-bounds index, preventing the microarchitecture from transiently reading and caching out-of-bounds kernel data. Affected CPE: cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* spanning all LoongArch kernel builds in the vulnerable stable series. No CWE was formally assigned, but this maps most accurately to CWE-1421 (Exposure of Sensitive Information in Shared Microarchitectural Structures during Transient Execution). A data conflict exists in the source intelligence: the vulnerability is mechanistically a speculative side-channel (information disclosure), yet the provided CVSS vector scores C:N/A:H, and the tags independently label it 'Information Disclosure' - this discrepancy is noted but not resolved from available data.