syscalls/mprotect.c

   1 /*
   2  * sys_mprotect(unsigned long start, size_t len, unsigned long prot)
   3  */
   4 #include <asm/mman.h>
   5 #include "utils.h"      // page_size
   6 #include "arch.h"
   7 #include "maps.h"
   8 #include "random.h"
   9 #include "sanitise.h"
  10 #include "shm.h"
  11
  12 static void sanitise_mprotect(int childno)
  13 {
  14         (void) common_set_mmap_ptr_len(childno);
  15 }
  16
  17 /*
  18  * If we successfully did an mprotect, update our record of the mappings prot bits.
  19  */
  20 static void post_mprotect(int childno)
  21 {
  22         struct map *map = (struct map *) shm->scratch[childno];
  23
  24         if (shm->retval[childno] != 0)
  25                 map->prot = shm->a3[childno];
  26
  27         shm->scratch[childno] = 0;
  28 }
  29
  30 struct syscallentry syscall_mprotect = {
  31         .name = "mprotect",
  32         .num_args = 3,
  33         .arg1name = "start",
  34         .arg1type = ARG_MMAP,
  35         .arg2name = "len",
  36         .arg3name = "prot",
  37         .arg3type = ARG_LIST,
  38         .arg3list = {
  39                 .num = 6,
  40                 .values = { PROT_READ, PROT_WRITE, PROT_EXEC, PROT_SEM, PROT_GROWSDOWN, PROT_GROWSUP },
  41         },
  42         .sanitise = sanitise_mprotect,
  43         .group = GROUP_VM,
  44         .post = post_mprotect,
  45 };