ipc/syscall.c

   1 /*
   2  * sys_ipc() is the old de-multiplexer for the SysV IPC calls.
   3  *
   4  * This is really horribly ugly, and new architectures should just wire up
   5  * the individual syscalls instead.
   6  */
   7 #include <linux/unistd.h>
   8 #include <linux/syscalls.h>
   9
  10 #ifdef __ARCH_WANT_SYS_IPC
  11 #include <linux/errno.h>
  12 #include <linux/ipc.h>
  13 #include <linux/shm.h>
  14 #include <linux/uaccess.h>
  15
  16 SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
  17                 unsigned long, third, void __user *, ptr, long, fifth)
  18 {
  19         int version, ret;
  20
  21         version = call >> 16; /* hack for backward compatibility */
  22         call &= 0xffff;
  23
  24         switch (call) {
  25         case SEMOP:
  26                 return sys_semtimedop(first, (struct sembuf __user *)ptr,
  27                                       second, NULL);
  28         case SEMTIMEDOP:
  29                 return sys_semtimedop(first, (struct sembuf __user *)ptr,
  30                                       second,
  31                                       (const struct timespec __user *)fifth);
  32
  33         case SEMGET:
  34                 return sys_semget(first, second, third);
  35         case SEMCTL: {
  36                 unsigned long arg;
  37                 if (!ptr)
  38                         return -EINVAL;
  39                 if (get_user(arg, (unsigned long __user *) ptr))
  40                         return -EFAULT;
  41                 return sys_semctl(first, second, third, arg);
  42         }
  43
  44         case MSGSND:
  45                 return sys_msgsnd(first, (struct msgbuf __user *) ptr,
  46                                   second, third);
  47         case MSGRCV:
  48                 switch (version) {
  49                 case 0: {
  50                         struct ipc_kludge tmp;
  51                         if (!ptr)
  52                                 return -EINVAL;
  53
  54                         if (copy_from_user(&tmp,
  55                                            (struct ipc_kludge __user *) ptr,
  56                                            sizeof(tmp)))
  57                                 return -EFAULT;
  58                         return sys_msgrcv(first, tmp.msgp, second,
  59                                            tmp.msgtyp, third);
  60                 }
  61                 default:
  62                         return sys_msgrcv(first,
  63                                            (struct msgbuf __user *) ptr,
  64                                            second, fifth, third);
  65                 }
  66         case MSGGET:
  67                 return sys_msgget((key_t) first, second);
  68         case MSGCTL:
  69                 return sys_msgctl(first, second, (struct msqid_ds __user *)ptr);
  70
  71         case SHMAT:
  72                 switch (version) {
  73                 default: {
  74                         unsigned long raddr;
  75                         ret = do_shmat(first, (char __user *)ptr,
  76                                        second, &raddr, SHMLBA);
  77                         if (ret)
  78                                 return ret;
  79                         return put_user(raddr, (unsigned long __user *) third);
  80                 }
  81                 case 1:
  82                         /*
  83                          * This was the entry point for kernel-originating calls
  84                          * from iBCS2 in 2.2 days.
  85                          */
  86                         return -EINVAL;
  87                 }
  88         case SHMDT:
  89                 return sys_shmdt((char __user *)ptr);
  90         case SHMGET:
  91                 return sys_shmget(first, second, third);
  92         case SHMCTL:
  93                 return sys_shmctl(first, second,
  94                                    (struct shmid_ds __user *) ptr);
  95         default:
  96                 return -ENOSYS;
  97         }
  98 }
  99 #endif
 100
 101 #ifdef CONFIG_COMPAT
 102 #include <linux/compat.h>
 103
 104 #ifndef COMPAT_SHMLBA
 105 #define COMPAT_SHMLBA   SHMLBA
 106 #endif
 107
 108 struct compat_ipc_kludge {
 109         compat_uptr_t msgp;
 110         compat_long_t msgtyp;
 111 };
 112
 113 #ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
 114 COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
 115         u32, third, compat_uptr_t, ptr, u32, fifth)
 116 {
 117         int version;
 118         u32 pad;
 119
 120         version = call >> 16; /* hack for backward compatibility */
 121         call &= 0xffff;
 122
 123         switch (call) {
 124         case SEMOP:
 125                 /* struct sembuf is the same on 32 and 64bit :)) */
 126                 return sys_semtimedop(first, compat_ptr(ptr), second, NULL);
 127         case SEMTIMEDOP:
 128                 return compat_sys_semtimedop(first, compat_ptr(ptr), second,
 129                                                 compat_ptr(fifth));
 130         case SEMGET:
 131                 return sys_semget(first, second, third);
 132         case SEMCTL:
 133                 if (!ptr)
 134                         return -EINVAL;
 135                 if (get_user(pad, (u32 __user *) compat_ptr(ptr)))
 136                         return -EFAULT;
 137                 return compat_sys_semctl(first, second, third, pad);
 138
 139         case MSGSND:
 140                 return compat_sys_msgsnd(first, ptr, second, third);
 141
 142         case MSGRCV: {
 143                 void __user *uptr = compat_ptr(ptr);
 144
 145                 if (first < 0 || second < 0)
 146                         return -EINVAL;
 147
 148                 if (!version) {
 149                         struct compat_ipc_kludge ipck;
 150                         if (!uptr)
 151                                 return -EINVAL;
 152                         if (copy_from_user(&ipck, uptr, sizeof(ipck)))
 153                                 return -EFAULT;
 154                         return compat_sys_msgrcv(first, ipck.msgp, second,
 155                                                  ipck.msgtyp, third);
 156                 }
 157                 return compat_sys_msgrcv(first, ptr, second, fifth, third);
 158         }
 159         case MSGGET:
 160                 return sys_msgget(first, second);
 161         case MSGCTL:
 162                 return compat_sys_msgctl(first, second, compat_ptr(ptr));
 163
 164         case SHMAT: {
 165                 int err;
 166                 unsigned long raddr;
 167
 168                 if (version == 1)
 169                         return -EINVAL;
 170                 err = do_shmat(first, compat_ptr(ptr), second, &raddr,
 171                                COMPAT_SHMLBA);
 172                 if (err < 0)
 173                         return err;
 174                 return put_user(raddr, (compat_ulong_t *)compat_ptr(third));
 175         }
 176         case SHMDT:
 177                 return sys_shmdt(compat_ptr(ptr));
 178         case SHMGET:
 179                 return sys_shmget(first, (unsigned)second, third);
 180         case SHMCTL:
 181                 return compat_sys_shmctl(first, second, compat_ptr(ptr));
 182         }
 183
 184         return -ENOSYS;
 185 }
 186 #endif
 187 #endif