// SPDX-License-Identifier: GPL-2.0 #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <stdint.h> #include <sys/prctl.h> #include <sys/utsname.h> #define SHIFT_TAG(tag) ((uint64_t)(tag) << 56) #define SET_TAG(ptr, tag) (((uint64_t)(ptr) & ~SHIFT_TAG(0xff)) | \ SHIFT_TAG(tag)) int main(void) { static int tbi_enabled = 0; unsigned long tag = 0; struct utsname *ptr; int err; if (prctl(PR_SET_TAGGED_ADDR_CTRL, PR_TAGGED_ADDR_ENABLE, 0, 0, 0) == 0) tbi_enabled = 1; ptr = (struct utsname *)malloc(sizeof(*ptr)); if (tbi_enabled) tag = 0x42; ptr = (struct utsname *)SET_TAG(ptr, tag); err = uname(ptr); free(ptr); return err; }