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/* This program should crash and produce coredump */
#include "compiler.h"
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <unistd.h>
#ifdef __FreeBSD__
#include <sys/types.h>
#include <sys/sysctl.h>
#include <sys/user.h>
#endif
#if defined(__linux__)
void write_maps(char *fname)
{
char buf[512], path[128];
char exec;
uintmax_t addr;
FILE *maps = fopen("/proc/self/maps", "r");
FILE *out = fopen(fname, "w");
if (!maps || !out)
exit(EXIT_FAILURE);
while (fgets(buf, sizeof(buf), maps))
{
if (sscanf(buf, "%jx-%*x %*c%*c%c%*c %*x %*s %*d /%126[^\n]", &addr, &exec, path+1) != 3)
continue;
if (exec != 'x')
continue;
path[0] = '/';
fprintf(out, "0x%jx:%s ", addr, path);
}
fprintf(out, "\n");
fclose(out);
fclose(maps);
}
#elif defined(__FreeBSD__)
void
write_maps(char *fname)
{
FILE *out;
char *buf, *bp, *eb;
struct kinfo_vmentry *kv;
int mib[4], error;
size_t len;
out = fopen(fname, "w");
if (out == NULL)
exit(EXIT_FAILURE);
len = 0;
mib[0] = CTL_KERN;
mib[1] = KERN_PROC;
mib[2] = KERN_PROC_VMMAP;
mib[3] = getpid();
error = sysctl(mib, 4, NULL, &len, NULL, 0);
if (error == -1)
exit(EXIT_FAILURE);
len = len * 4 / 3;
buf = malloc(len);
if (buf == NULL)
exit(EXIT_FAILURE);
error = sysctl(mib, 4, buf, &len, NULL, 0);
if (error == -1)
exit(EXIT_FAILURE);
for (bp = buf, eb = buf + len; bp < eb; bp += kv->kve_structsize) {
kv = (struct kinfo_vmentry *)(uintptr_t)bp;
if (kv->kve_type == KVME_TYPE_VNODE &&
(kv->kve_protection & KVME_PROT_EXEC) != 0) {
fprintf(out, "0x%jx:%s ", kv->kve_start, kv->kve_path);
}
}
fprintf(out, "\n");
fclose(out);
free(buf);
}
#else
#error Port me
#endif
#ifdef __GNUC__
#ifndef __clang__
// Gcc >= 8 became too good at inlining alias c into b when using -O2 or -O3,
// so force -O1 in all cases, otherwise a frame will be missing in the tests.
#pragma GCC optimize "-O1"
#endif
int c(int x) NOINLINE ALIAS(b);
#define compiler_barrier() __asm__ __volatile__ ("");
#else
int c(int x);
#define compiler_barrier()
#endif
int NOINLINE a(void)
{
*(volatile int *)32 = 1;
return 1;
}
int NOINLINE b(int x)
{
int r;
compiler_barrier();
if (x)
r = a();
else
r = c(1);
return r + 1;
}
int
main (int argc, char **argv)
{
if (argc > 1)
write_maps(argv[1]);
b(0);
return 0;
}
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