// https://syzkaller.appspot.com/bug?id=cd8b9cfe50a0bf36ee19eda2d7e2e06843dfbeaf // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include unsigned long long procid; static void sleep_ms(uint64_t ms) { usleep(ms * 1000); } #define USB_MAX_EP_NUM 32 struct usb_device_index { struct usb_device_descriptor* dev; struct usb_config_descriptor* config; unsigned config_length; struct usb_interface_descriptor* iface; struct usb_endpoint_descriptor* eps[USB_MAX_EP_NUM]; unsigned eps_num; }; static bool parse_usb_descriptor(char* buffer, size_t length, struct usb_device_index* index) { if (length < sizeof(*index->dev) + sizeof(*index->config) + sizeof(*index->iface)) return false; index->dev = (struct usb_device_descriptor*)buffer; index->config = (struct usb_config_descriptor*)(buffer + sizeof(*index->dev)); index->config_length = length - sizeof(*index->dev); index->iface = (struct usb_interface_descriptor*)(buffer + sizeof(*index->dev) + sizeof(*index->config)); index->eps_num = 0; size_t offset = 0; while (true) { if (offset == length) break; if (offset + 1 < length) break; uint8_t length = buffer[offset]; uint8_t type = buffer[offset + 1]; if (type == USB_DT_ENDPOINT) { index->eps[index->eps_num] = (struct usb_endpoint_descriptor*)(buffer + offset); index->eps_num++; } if (index->eps_num == USB_MAX_EP_NUM) break; offset += length; } return true; } enum usb_fuzzer_event_type { USB_FUZZER_EVENT_INVALID, USB_FUZZER_EVENT_CONNECT, USB_FUZZER_EVENT_DISCONNECT, USB_FUZZER_EVENT_SUSPEND, USB_FUZZER_EVENT_RESUME, USB_FUZZER_EVENT_CONTROL, }; struct usb_fuzzer_event { uint32_t type; uint32_t length; char data[0]; }; struct usb_fuzzer_init { uint64_t speed; const char* driver_name; const char* device_name; }; struct usb_fuzzer_ep_io { uint16_t ep; uint16_t flags; uint32_t length; char data[0]; }; #define USB_FUZZER_IOCTL_INIT _IOW('U', 0, struct usb_fuzzer_init) #define USB_FUZZER_IOCTL_RUN _IO('U', 1) #define USB_FUZZER_IOCTL_EP0_READ _IOWR('U', 2, struct usb_fuzzer_event) #define USB_FUZZER_IOCTL_EP0_WRITE _IOW('U', 3, struct usb_fuzzer_ep_io) #define USB_FUZZER_IOCTL_EP_ENABLE _IOW('U', 4, struct usb_endpoint_descriptor) #define USB_FUZZER_IOCTL_EP_WRITE _IOW('U', 6, struct usb_fuzzer_ep_io) #define USB_FUZZER_IOCTL_CONFIGURE _IO('U', 8) #define USB_FUZZER_IOCTL_VBUS_DRAW _IOW('U', 9, uint32_t) int usb_fuzzer_open() { return open("/sys/kernel/debug/usb-fuzzer", O_RDWR); } int usb_fuzzer_init(int fd, uint32_t speed, const char* driver, const char* device) { struct usb_fuzzer_init arg; arg.speed = speed; arg.driver_name = driver; arg.device_name = device; return ioctl(fd, USB_FUZZER_IOCTL_INIT, &arg); } int usb_fuzzer_run(int fd) { return ioctl(fd, USB_FUZZER_IOCTL_RUN, 0); } int usb_fuzzer_ep0_read(int fd, struct usb_fuzzer_event* event) { return ioctl(fd, USB_FUZZER_IOCTL_EP0_READ, event); } int usb_fuzzer_ep0_write(int fd, struct usb_fuzzer_ep_io* io) { return ioctl(fd, USB_FUZZER_IOCTL_EP0_WRITE, io); } int usb_fuzzer_ep_write(int fd, struct usb_fuzzer_ep_io* io) { return ioctl(fd, USB_FUZZER_IOCTL_EP_WRITE, io); } int usb_fuzzer_ep_enable(int fd, struct usb_endpoint_descriptor* desc) { return ioctl(fd, USB_FUZZER_IOCTL_EP_ENABLE, desc); } int usb_fuzzer_configure(int fd) { return ioctl(fd, USB_FUZZER_IOCTL_CONFIGURE, 0); } int usb_fuzzer_vbus_draw(int fd, uint32_t power) { return ioctl(fd, USB_FUZZER_IOCTL_VBUS_DRAW, power); } #define USB_MAX_PACKET_SIZE 1024 struct usb_fuzzer_control_event { struct usb_fuzzer_event inner; struct usb_ctrlrequest ctrl; }; struct usb_fuzzer_ep_io_data { struct usb_fuzzer_ep_io inner; char data[USB_MAX_PACKET_SIZE]; }; struct vusb_connect_string_descriptor { uint32_t len; char* str; } __attribute__((packed)); struct vusb_connect_descriptors { uint32_t qual_len; char* qual; uint32_t bos_len; char* bos; uint32_t strs_len; struct vusb_connect_string_descriptor strs[0]; } __attribute__((packed)); static volatile long syz_usb_connect(volatile long a0, volatile long a1, volatile long a2, volatile long a3) { int64_t speed = a0; int64_t dev_len = a1; char* dev = (char*)a2; struct vusb_connect_descriptors* conn_descs = (struct vusb_connect_descriptors*)a3; if (!dev) return -1; struct usb_device_index index; memset(&index, 0, sizeof(index)); int rv = parse_usb_descriptor(dev, dev_len, &index); if (!rv) return -1; int fd = usb_fuzzer_open(); if (fd < 0) return -1; char device[32]; sprintf(&device[0], "dummy_udc.%llu", procid); rv = usb_fuzzer_init(fd, speed, "dummy_udc", &device[0]); if (rv < 0) return -1; rv = usb_fuzzer_run(fd); if (rv < 0) return -1; bool done = false; while (!done) { char* response_data = NULL; uint32_t response_length = 0; unsigned ep; uint8_t str_idx; struct usb_fuzzer_control_event event; event.inner.type = 0; event.inner.length = sizeof(event.ctrl); rv = usb_fuzzer_ep0_read(fd, (struct usb_fuzzer_event*)&event); if (rv < 0) return -1; if (event.inner.type != USB_FUZZER_EVENT_CONTROL) continue; switch (event.ctrl.bRequestType & USB_TYPE_MASK) { case USB_TYPE_STANDARD: switch (event.ctrl.bRequest) { case USB_REQ_GET_DESCRIPTOR: switch (event.ctrl.wValue >> 8) { case USB_DT_DEVICE: response_data = (char*)index.dev; response_length = sizeof(*index.dev); goto reply; case USB_DT_CONFIG: response_data = (char*)index.config; response_length = index.config_length; goto reply; case USB_DT_STRING: str_idx = (uint8_t)event.ctrl.wValue; if (str_idx >= conn_descs->strs_len) goto reply; response_data = conn_descs->strs[str_idx].str; response_length = conn_descs->strs[str_idx].len; goto reply; case USB_DT_BOS: response_data = conn_descs->bos; response_length = conn_descs->bos_len; goto reply; case USB_DT_DEVICE_QUALIFIER: response_data = conn_descs->qual; response_length = conn_descs->qual_len; goto reply; default: exit(1); continue; } break; case USB_REQ_SET_CONFIGURATION: rv = usb_fuzzer_vbus_draw(fd, index.config->bMaxPower); if (rv < 0) return -1; rv = usb_fuzzer_configure(fd); if (rv < 0) return -1; for (ep = 0; ep < index.eps_num; ep++) { rv = usb_fuzzer_ep_enable(fd, index.eps[ep]); if (rv < 0) exit(1); } done = true; goto reply; default: exit(1); continue; } break; default: exit(1); continue; } struct usb_fuzzer_ep_io_data response; reply: response.inner.ep = 0; response.inner.flags = 0; if (response_length > sizeof(response.data)) response_length = 0; response.inner.length = response_length; if (response_data) memcpy(&response.data[0], response_data, response_length); if (event.ctrl.wLength < response.inner.length) response.inner.length = event.ctrl.wLength; usb_fuzzer_ep0_write(fd, (struct usb_fuzzer_ep_io*)&response); } sleep_ms(200); return fd; } int main(void) { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); *(uint8_t*)0x20005100 = 0x12; *(uint8_t*)0x20005101 = 1; *(uint16_t*)0x20005102 = 0; *(uint8_t*)0x20005104 = 0xc7; *(uint8_t*)0x20005105 = 0x40; *(uint8_t*)0x20005106 = 0xb; *(uint8_t*)0x20005107 = 8; *(uint16_t*)0x20005108 = 0xcf3; *(uint16_t*)0x2000510a = 0x9374; *(uint16_t*)0x2000510c = 0xa3f9; *(uint8_t*)0x2000510e = 0; *(uint8_t*)0x2000510f = 0; *(uint8_t*)0x20005110 = 0; *(uint8_t*)0x20005111 = 1; *(uint8_t*)0x20005112 = 9; *(uint8_t*)0x20005113 = 2; *(uint16_t*)0x20005114 = 0x1d; *(uint8_t*)0x20005116 = 1; *(uint8_t*)0x20005117 = 0; *(uint8_t*)0x20005118 = 0; *(uint8_t*)0x20005119 = 0; *(uint8_t*)0x2000511a = 0; *(uint8_t*)0x2000511b = 9; *(uint8_t*)0x2000511c = 4; *(uint8_t*)0x2000511d = 0x2f; *(uint8_t*)0x2000511e = 0; *(uint8_t*)0x2000511f = 1; *(uint8_t*)0x20005120 = 0xaa; *(uint8_t*)0x20005121 = 0x6c; *(uint8_t*)0x20005122 = 0x94; *(uint8_t*)0x20005123 = 0; *(uint8_t*)0x20005124 = 7; *(uint8_t*)0x20005125 = 5; *(uint8_t*)0x20005126 = -1; *(uint8_t*)0x20005127 = 0x10; *(uint16_t*)0x20005128 = 0x401; *(uint8_t*)0x2000512a = 0xdf; *(uint8_t*)0x2000512b = 7; *(uint8_t*)0x2000512c = 1; *(uint8_t*)0x2000512d = 2; *(uint8_t*)0x2000512e = 0x3f; syz_usb_connect(3, 0x2f, 0x20005100, 0); return 0; }