syscalls/fanotify_mark.c

   1 /*
   2  * SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags,
   3         __u64 mask, int dfd, const char  __user * pathname)
   4  */
   5 #include <stdlib.h>
   6 #include "sanitise.h"
   7 #include "shm.h"
   8
   9 /* flags used for fanotify_modify_mark() */
  10 #define FAN_MARK_ADD            0x00000001
  11 #define FAN_MARK_REMOVE         0x00000002
  12 #define FAN_MARK_DONT_FOLLOW    0x00000004
  13 #define FAN_MARK_ONLYDIR        0x00000008
  14 #define FAN_MARK_MOUNT          0x00000010
  15 #define FAN_MARK_IGNORED_MASK   0x00000020
  16 #define FAN_MARK_IGNORED_SURV_MODIFY    0x00000040
  17 #define FAN_MARK_FLUSH          0x00000080
  18
  19 #define FAN_ACCESS              0x00000001      /* File was accessed */
  20 #define FAN_MODIFY              0x00000002      /* File was modified */
  21 #define FAN_CLOSE_WRITE         0x00000008      /* Writtable file closed */
  22 #define FAN_CLOSE_NOWRITE       0x00000010      /* Unwrittable file closed */
  23 #define FAN_OPEN                0x00000020      /* File was opened */
  24
  25 #define FAN_Q_OVERFLOW          0x00004000      /* Event queued overflowed */
  26
  27 #define FAN_OPEN_PERM           0x00010000      /* File open in perm check */
  28 #define FAN_ACCESS_PERM         0x00020000      /* File accessed in perm check */
  29
  30 #define FAN_ONDIR               0x40000000      /* event occurred against dir */
  31
  32 #define FAN_EVENT_ON_CHILD      0x08000000      /* interested in child events */
  33 #define FAN_CLOSE               (FAN_CLOSE_WRITE | FAN_CLOSE_NOWRITE) /* close */
  34
  35 static void sanitise_fanotify_mark(int childno)
  36 {
  37         unsigned int flagvals[5] = { FAN_MARK_DONT_FOLLOW, FAN_MARK_ONLYDIR, FAN_MARK_MOUNT,
  38                                     FAN_MARK_IGNORED_MASK, FAN_MARK_IGNORED_SURV_MODIFY };
  39
  40         unsigned int i;
  41         unsigned int numflags = rand() % 5;
  42
  43         // set additional flags
  44         for (i = 0; i < numflags; i++)
  45                 shm->a2[childno] |= flagvals[i];
  46
  47         // Set mask
  48         shm->a3[childno] &= 0xffffffff;
  49 }
  50
  51 struct syscallentry syscall_fanotify_mark = {
  52         .name = "fanotify_mark",
  53         .num_args = 5,
  54         .arg1name = "fanotify_fd",
  55         .arg1type = ARG_FD,
  56         .arg2name = "flags",
  57         .arg2type = ARG_OP,
  58         .arg2list = {
  59                 .num = 3,
  60                 .values = { FAN_MARK_ADD, FAN_MARK_REMOVE, FAN_MARK_FLUSH },
  61         },
  62         .arg3name = "mask",
  63         .arg3type = ARG_LIST,
  64         .arg3list = {
  65                 .num = 7,
  66                 .values = { FAN_ACCESS, FAN_MODIFY, FAN_CLOSE, FAN_OPEN,
  67                             FAN_OPEN_PERM, FAN_ACCESS_PERM,
  68                             FAN_EVENT_ON_CHILD },
  69         },
  70         .arg4name = "dfd",
  71         .arg4type = ARG_FD,
  72         .arg5name = "pathname",
  73         .arg5type = ARG_PATHNAME,
  74         .sanitise = sanitise_fanotify_mark,
  75         .rettype = RET_ZERO_SUCCESS,
  76         .flags = NEED_ALARM,
  77         .group = GROUP_VFS,
  78 };