syscalls/splice.c

   1 /*
   2  * SYSCALL_DEFINE6(splice, int, fd_in, loff_t __user *, off_in,
   3         int, fd_out, loff_t __user *, off_out,
   4         size_t, len, unsigned int, flags)
   5  */
   6 #include <stdlib.h>
   7 #include "sanitise.h"
   8 #include "random.h"
   9 #include "shm.h"
  10
  11 # define SPLICE_F_MOVE          1       /* Move pages instead of copying.  */
  12 # define SPLICE_F_NONBLOCK      2       /* Don't block on the pipe splicing
  13                                            (but we may still block on the fd
  14                                            we splice from/to).  */
  15 # define SPLICE_F_MORE          4       /* Expect more data.  */
  16 # define SPLICE_F_GIFT          8       /* Pages passed in are a gift.  */
  17
  18 static void sanitise_splice(int childno)
  19 {
  20         if ((rand() % 10) < 3)
  21                 return;
  22
  23         if (rand_bool()) {
  24                 shm->syscall[childno].a1 = shm->pipe_fds[rand() % MAX_PIPE_FDS];
  25                 shm->syscall[childno].a2 = 0;
  26         }
  27
  28         if (rand_bool()) {
  29                 shm->syscall[childno].a3 = shm->pipe_fds[rand() % MAX_PIPE_FDS];
  30                 shm->syscall[childno].a4 = 0;
  31         }
  32 }
  33
  34 struct syscallentry syscall_splice = {
  35         .name = "splice",
  36         .num_args = 6,
  37         .arg1name = "fd_in",
  38         .arg1type = ARG_FD,
  39         .arg2name = "off_in",
  40         .arg2type = ARG_ADDRESS,
  41         .arg3name = "fd_out",
  42         .arg3type = ARG_FD,
  43         .arg4name = "off_out",
  44         .arg4type = ARG_ADDRESS,
  45         .arg5name = "len",
  46         .arg5type = ARG_LEN,
  47         .arg6name = "flags",
  48         .arg6type = ARG_LIST,
  49         .arg6list = {
  50                 .num = 4,
  51                 .values = { SPLICE_F_MOVE, SPLICE_F_NONBLOCK, SPLICE_F_MORE, SPLICE_F_GIFT },
  52         },
  53         .sanitise = sanitise_splice,
  54         .flags = NEED_ALARM,
  55 };