chkheap.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, char* argv){
  printf("PID=%d\n", getpid());
  printf("Run bpftrace background and hit return:\n");
  (void)fgetc(stdin);

  char *relm1, *relm2, *relm3;
  char cmd[256] = {0};
  snprintf(cmd, 256,\
           "cat /proc/%d/maps", getpid());
  system(cmd);
  int i;

  relm1 = malloc(1024);
  // relm1 = malloc(1 * 1024 * 1024 * 1024);
  relm1[0] = 'a';
  printf("relm1: %p\n", relm1);
  sleep(1);

  relm2 = malloc(1024 * 1024 * 1024);
  printf("relm2: %p\n", relm2);
  sleep(1);

  puts("");
  snprintf(cmd, 256,\
           "cat /proc/%d/maps", getpid());
  system(cmd);
  (void)fgetc(stdin);

  free(relm2);
  free(relm1);
  printf("All freed.\n");
  return 0; 
}

ZZ-log.console

$ ./chkheap 
PID=7319
Run bpftrace background and hit return:

55a46e740000-55a46e741000 r-xp 00000000 08:01 22338                      /home/vagrant/chkheap
55a46e940000-55a46e941000 r--p 00000000 08:01 22338                      /home/vagrant/chkheap
55a46e941000-55a46e942000 rw-p 00001000 08:01 22338                      /home/vagrant/chkheap
55a4705d0000-55a4705f1000 rw-p 00000000 00:00 0                          [heap]
7f341d659000-7f341d840000 r-xp 00000000 08:01 21679                      /lib/x86_64-linux-gnu/libc-2.27.so
7f341d840000-7f341da40000 ---p 001e7000 08:01 21679                      /lib/x86_64-linux-gnu/libc-2.27.so
7f341da40000-7f341da44000 r--p 001e7000 08:01 21679                      /lib/x86_64-linux-gnu/libc-2.27.so
7f341da44000-7f341da46000 rw-p 001eb000 08:01 21679                      /lib/x86_64-linux-gnu/libc-2.27.so
7f341da46000-7f341da4a000 rw-p 00000000 00:00 0 
7f341da4a000-7f341da71000 r-xp 00000000 08:01 21675                      /lib/x86_64-linux-gnu/ld-2.27.so
7f341dc65000-7f341dc67000 rw-p 00000000 00:00 0 
7f341dc71000-7f341dc72000 r--p 00027000 08:01 21675                      /lib/x86_64-linux-gnu/ld-2.27.so
7f341dc72000-7f341dc73000 rw-p 00028000 08:01 21675                      /lib/x86_64-linux-gnu/ld-2.27.so
7f341dc73000-7f341dc74000 rw-p 00000000 00:00 0 
7ffeb1150000-7ffeb1171000 rw-p 00000000 00:00 0                          [stack]
7ffeb11cf000-7ffeb11d2000 r--p 00000000 00:00 0                          [vvar]
7ffeb11d2000-7ffeb11d3000 r-xp 00000000 00:00 0                          [vdso]
ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0                  [vsyscall]
relm1: 0x55a4705d0a80
relm2: 0x7f33dd658010

55a46e740000-55a46e741000 r-xp 00000000 08:01 22338                      /home/vagrant/chkheap
55a46e940000-55a46e941000 r--p 00000000 08:01 22338                      /home/vagrant/chkheap
55a46e941000-55a46e942000 rw-p 00001000 08:01 22338                      /home/vagrant/chkheap
55a4705d0000-55a4705f1000 rw-p 00000000 00:00 0                          [heap]
7f33dd658000-7f341d659000 rw-p 00000000 00:00 0 
7f341d659000-7f341d840000 r-xp 00000000 08:01 21679                      /lib/x86_64-linux-gnu/libc-2.27.so
7f341d840000-7f341da40000 ---p 001e7000 08:01 21679                      /lib/x86_64-linux-gnu/libc-2.27.so
7f341da40000-7f341da44000 r--p 001e7000 08:01 21679                      /lib/x86_64-linux-gnu/libc-2.27.so
7f341da44000-7f341da46000 rw-p 001eb000 08:01 21679                      /lib/x86_64-linux-gnu/libc-2.27.so
7f341da46000-7f341da4a000 rw-p 00000000 00:00 0 
7f341da4a000-7f341da71000 r-xp 00000000 08:01 21675                      /lib/x86_64-linux-gnu/ld-2.27.so
7f341dc65000-7f341dc67000 rw-p 00000000 00:00 0 
7f341dc71000-7f341dc72000 r--p 00027000 08:01 21675                      /lib/x86_64-linux-gnu/ld-2.27.so
7f341dc72000-7f341dc73000 rw-p 00028000 08:01 21675                      /lib/x86_64-linux-gnu/ld-2.27.so
7f341dc73000-7f341dc74000 rw-p 00000000 00:00 0 
7ffeb1150000-7ffeb1171000 rw-p 00000000 00:00 0                          [stack]
7ffeb11cf000-7ffeb11d2000 r--p 00000000 00:00 0                          [vvar]
7ffeb11d2000-7ffeb11d3000 r-xp 00000000 00:00 0                          [vdso]
ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0                  [vsyscall]

All freed.