kernel - Implement spectre mitigations part 1
[dragonfly.git] / test / debug / buserr.c
blobc7dfb4205a08d6776bf779e2b0ba35e95663d24a
1 /*
2 * Test a fork/munmap vm_object shadow chain race
4 * Written by "Samuel J. Greear" <sjg@evilcode.net>
5 */
6 #include <stdio.h>
7 #include <string.h>
8 #include <err.h>
9 #include <sysexits.h>
10 #include <unistd.h>
12 #include <sys/types.h>
13 #include <sys/mman.h>
14 #include <sys/param.h>
15 #include <sys/wait.h>
17 #define MAPPING_PAGES 4096
19 int
20 main(int argc, char *argv[])
22 unsigned int i, size;
23 int status;
24 pid_t pid;
25 void *mapping;
26 char tmp[100];
28 for (i = 1; i < MAPPING_PAGES; ++i) {
29 size = PAGE_SIZE * i;
30 mapping = mmap(0, size, PROT_READ|PROT_WRITE, MAP_ANON|MAP_SHARED,
31 -1, 0);
32 if (mapping == MAP_FAILED)
33 errx(EX_OSERR, "mmap() failed");
35 memset(mapping, 'x', 10);
36 printf(" %d", i);
37 fflush(stdout);
39 pid = fork();
40 if (pid == 0) {
41 memcpy(&tmp, mapping, 12);
42 return (0);
43 } else if (pid != -1) {
44 if (munmap(mapping, PAGE_SIZE * i) != 0) {
45 printf("munmap failed\n");
46 return (0);
48 waitpid(pid, &status, 0);
49 if (status == 10) {
50 printf("child sig10 at %d pages\n", i);
51 return (0);
53 } else {
54 printf("fork failed\n");
58 return (0);