syscalls/mbind.c

   1 /*
   2  * SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len,
   3         unsigned long, mode, unsigned long __user *, nmask,
   4         unsigned long, maxnode, unsigned, flags)
   5  */
   6
   7 #include <linux/mempolicy.h>
   8 #include "arch.h"
   9 #include "maps.h"
  10 #include "random.h"
  11 #include "sanitise.h"
  12 #include "shm.h"
  13 #include "utils.h"      // page_size
  14
  15 #define MPOL_F_STATIC_NODES     (1 << 15)
  16 #define MPOL_F_RELATIVE_NODES   (1 << 14)
  17
  18 static void sanitise_mbind(int childno)
  19 {
  20         unsigned long maxnode;
  21
  22         (void) common_set_mmap_ptr_len(childno);
  23
  24 retry_maxnode:
  25         shm->a5[childno] &= ~((page_size * 8) - 1);
  26
  27         maxnode = shm->a5[childno];
  28
  29         if (maxnode < 2 || maxnode > (page_size * 8)) {
  30                 shm->a5[childno] = rand32();
  31                 goto retry_maxnode;
  32         }
  33 }
  34
  35
  36 struct syscallentry syscall_mbind = {
  37         .name = "mbind",
  38         .num_args = 6,
  39         .arg1name = "start",
  40         .arg1type = ARG_MMAP,
  41
  42         .arg2name = "len",
  43
  44         .arg3name = "mode",
  45         .arg3type = ARG_LIST,
  46         .arg3list = {
  47                 .num = 4,
  48                 .values = { MPOL_DEFAULT, MPOL_BIND, MPOL_INTERLEAVE, MPOL_PREFERRED },
  49         },
  50
  51         .arg4name = "nmask",
  52         .arg4type = ARG_ADDRESS,
  53
  54         .arg5name = "maxnode",
  55         .arg5type = ARG_RANGE,
  56         .low5range = 0,
  57         .hi5range = 32,
  58
  59         .arg6name = "flags",
  60         .arg6type = ARG_LIST,
  61         .arg6list = {
  62                 .num = 2,
  63                 .values = { MPOL_F_STATIC_NODES, MPOL_F_RELATIVE_NODES },
  64         },
  65         .sanitise = sanitise_mbind,
  66         .group = GROUP_VM,
  67 };