CVE-2026-23383 Linux内核BPF JIT内存对齐漏洞

#include <stdio.h> #include <stdint.h> // Simulating the vulnerable structure layout struct bpf_plt { uint32_t dummy; // Simulating padding/other fields uint64_t target; // Requires 8-byte alignment }; /* * PoC Logic: * To trigger this vulnerability, an attacker needs to: * 1. Load a specific eBPF program that forces the JIT compiler * to allocate a buffer at a 4-byte aligned address (e.g., ending in 0x4). * 2. The JIT builds a PLT (Procedure Linkage Table) entry where 'target' * is misaligned. * 3. Trigger a concurrent update to 'target' via bpf_arch_text_poke() * while the JIT'd code executes an ldr instruction from that address. * 4. On ARM64, this causes a torn read (atomicity violation), * leading to a jump to a corrupted address. */ int main() { printf("PoC for CVE-2026-23383: BPF JIT Atomic Tearing\n"); printf("Requires: ARM64 Linux Kernel with vulnerable BPF JIT\n"); printf("Impact: Kernel crash or potential code execution\n"); return 0; }