shm.c

   1 /*
   2  * Shared mapping creation.
   3  */
   4
   5 #include <stdlib.h>
   6 #include <string.h>
   7 #include <unistd.h>
   8 #include <sys/mman.h>
   9 #include "arch.h"
  10 #include "child.h"
  11 #include "log.h"
  12 #include "params.h"
  13 #include "pids.h"
  14 #include "random.h"
  15 #include "shm.h"
  16 #include "utils.h"
  17
  18 struct shm_s *shm;
  19
  20 #define SHM_PROT_PAGES 30
  21
  22 void create_shm(void)
  23 {
  24         void *p;
  25         unsigned int shm_pages;
  26
  27         /* round up shm to nearest page size */
  28         shm_pages = ((sizeof(struct shm_s) + page_size - 1) & ~(page_size - 1)) / page_size;
  29
  30         /* Waste some address space to set up some "protection" near the SHM location. */
  31         p = alloc_shared((SHM_PROT_PAGES + shm_pages + SHM_PROT_PAGES) * page_size);
  32
  33         /* clear whole mapping, including the redzones. */
  34         memset(p, 0, shm_pages * page_size);
  35
  36         /* set the redzones to PROT_NONE */
  37         mprotect(p, SHM_PROT_PAGES * page_size, PROT_NONE);
  38         mprotect(p + (SHM_PROT_PAGES + shm_pages) * page_size,
  39                         SHM_PROT_PAGES * page_size, PROT_NONE);
  40
  41         shm = p + SHM_PROT_PAGES * page_size;
  42 }
  43
  44 void create_shm_arrays(void)
  45 {
  46         shm->child_syscall_count = alloc_shared(max_children * sizeof(unsigned long));
  47
  48         shm->pids = alloc_shared(max_children * sizeof(pid_t));
  49
  50         shm->tv = alloc_shared(max_children * sizeof(struct timeval));
  51
  52         shm->previous_syscallno = alloc_shared(max_children * sizeof(unsigned int));
  53         shm->syscallno = alloc_shared(max_children * sizeof(unsigned int));
  54
  55         shm->previous_a1 = alloc_shared(max_children * sizeof(unsigned long));
  56         shm->previous_a2 = alloc_shared(max_children * sizeof(unsigned long));
  57         shm->previous_a3 = alloc_shared(max_children * sizeof(unsigned long));
  58         shm->previous_a4 = alloc_shared(max_children * sizeof(unsigned long));
  59         shm->previous_a5 = alloc_shared(max_children * sizeof(unsigned long));
  60         shm->previous_a6 = alloc_shared(max_children * sizeof(unsigned long));
  61
  62         shm->a1 = alloc_shared(max_children * sizeof(unsigned long));
  63         shm->a2 = alloc_shared(max_children * sizeof(unsigned long));
  64         shm->a3 = alloc_shared(max_children * sizeof(unsigned long));
  65         shm->a4 = alloc_shared(max_children * sizeof(unsigned long));
  66         shm->a5 = alloc_shared(max_children * sizeof(unsigned long));
  67         shm->a6 = alloc_shared(max_children * sizeof(unsigned long));
  68
  69         shm->mappings = alloc_shared(max_children * sizeof(struct map *));
  70         shm->num_mappings = alloc_shared(max_children * sizeof(unsigned int));
  71
  72         shm->seeds = alloc_shared(max_children * sizeof(int));
  73         shm->child_type = alloc_shared(max_children * sizeof(unsigned char));
  74         shm->kill_count = alloc_shared(max_children * sizeof(unsigned char));
  75         shm->logfiles = alloc_shared(max_children * sizeof(FILE *));
  76         shm->retval = alloc_shared(max_children * sizeof(unsigned long));
  77         shm->scratch = alloc_shared(max_children * sizeof(unsigned long));
  78         shm->do32bit = alloc_shared(max_children * sizeof(bool));
  79 }
  80
  81 void init_shm(void)
  82 {
  83         unsigned int i;
  84
  85         output(2, "shm is at %p\n", shm);
  86
  87         shm->total_syscalls_done = 1;
  88
  89         if (user_set_seed == TRUE)
  90                 shm->seed = init_seed(seed);
  91         else
  92                 shm->seed = new_seed();
  93         /* Set seed in parent thread */
  94         set_seed(0);
  95
  96         for (i = 0; i < max_children; i++) {
  97
  98                 shm->pids[i] = EMPTY_PIDSLOT;
  99
 100                 shm->previous_syscallno[i] = -1;
 101                 shm->syscallno[i] = -1;
 102
 103                 shm->previous_a1[i] = shm->a1[i] = -1;
 104                 shm->previous_a2[i] = shm->a2[i] = -1;
 105                 shm->previous_a3[i] = shm->a3[i] = -1;
 106                 shm->previous_a4[i] = shm->a4[i] = -1;
 107                 shm->previous_a5[i] = shm->a5[i] = -1;
 108                 shm->previous_a6[i] = shm->a6[i] = -1;
 109         }
 110 }