1 // SPDX-License-Identifier: GPL-2.0 2 3 #include <stdio.h> 4 #include <stdlib.h> 5 #include <unistd.h> 6 #include <stdint.h> 7 #include <sys/prctl.h> 8 #include <sys/utsname.h> 9 10 #define SHIFT_TAG(tag) ((uint64_t)(tag) << 56) 11 #define SET_TAG(ptr, tag) (((uint64_t)(ptr) & ~SHIFT_TAG(0xff)) | \ 12 SHIFT_TAG(tag)) 13 14 int main(void) 15 { 16 static int tbi_enabled = 0; 17 unsigned long tag = 0; 18 struct utsname *ptr; 19 int err; 20 21 if (prctl(PR_SET_TAGGED_ADDR_CTRL, PR_TAGGED_ADDR_ENABLE, 0, 0, 0) == 0) 22 tbi_enabled = 1; 23 ptr = (struct utsname *)malloc(sizeof(*ptr)); 24 if (tbi_enabled) 25 tag = 0x42; 26 ptr = (struct utsname *)SET_TAG(ptr, tag); 27 err = uname(ptr); 28 free(ptr); 29 30 return err; 31 } 32