mirror of https://github.com/rust-lang/rust
48 lines
1.2 KiB
C
48 lines
1.2 KiB
C
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <stdint.h>
|
|
#include "bar.h"
|
|
|
|
extern void foo(unsigned int *);
|
|
|
|
void bar(char *ptr) {
|
|
if (((uintptr_t)ptr >> 56) != 0x1f) {
|
|
fprintf(stderr, "Top byte corrupted on Rust -> C FFI boundary!\n");
|
|
exit(1);
|
|
}
|
|
}
|
|
|
|
int main(void)
|
|
{
|
|
// Construct a pointer with an arbitrary tag in bits 56-59, simulating an MTE tag.
|
|
// It's only necessary that the tag is preserved across FFI bounds for this test.
|
|
unsigned int *ptr;
|
|
|
|
ptr = alloc_page();
|
|
if (ptr == MAP_FAILED)
|
|
{
|
|
perror("mmap() failed");
|
|
return EXIT_FAILURE;
|
|
}
|
|
|
|
// Store an arbitrary tag in bits 56-59 of the pointer (where an MTE tag may be),
|
|
// and a different value in the ignored top 4 bits.
|
|
ptr = (unsigned int *)((uintptr_t)ptr | 0x1fl << 56);
|
|
|
|
if (mte_enabled()) {
|
|
set_tag(ptr);
|
|
}
|
|
|
|
ptr[0] = 61;
|
|
ptr[1] = 62;
|
|
|
|
foo(ptr); // should change the contents of the page to start with 0x63 0x64 and call `bar`
|
|
|
|
if (ptr[0] != 0x63 || ptr[1] != 0x64) {
|
|
fprintf(stderr, "invalid data in memory; expected '63 64', got '%d %d'\n", ptr[0], ptr[1]);
|
|
return EXIT_FAILURE;
|
|
}
|
|
|
|
return 0;
|
|
}
|