// SPDX-License-Identifier: GPL-2.0

  /*
   * sys_ipc() is the old de-multiplexer for the SysV IPC calls.
   *
   * This is really horribly ugly, and new architectures should just wire up
   * the individual syscalls instead.
   */
  #include <linux/unistd.h>

  #include <linux/syscalls.h>

  
  #ifdef __ARCH_WANT_SYS_IPC
  #include <linux/errno.h>
  #include <linux/ipc.h>
  #include <linux/shm.h>

  #include <linux/uaccess.h>

  SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,

  		unsigned long, third, void __user *, ptr, long, fifth)
  {
  	int version, ret;
  
  	version = call >> 16; /* hack for backward compatibility */
  	call &= 0xffff;
  
  	switch (call) {
  	case SEMOP:
  		return sys_semtimedop(first, (struct sembuf __user *)ptr,
  				      second, NULL);
  	case SEMTIMEDOP:
  		return sys_semtimedop(first, (struct sembuf __user *)ptr,
  				      second,
  				      (const struct timespec __user *)fifth);
  
  	case SEMGET:
  		return sys_semget(first, second, third);
  	case SEMCTL: {

  		unsigned long arg;

  		if (!ptr)
  			return -EINVAL;

  		if (get_user(arg, (unsigned long __user *) ptr))

  			return -EFAULT;

  		return sys_semctl(first, second, third, arg);

  	}
  
  	case MSGSND:
  		return sys_msgsnd(first, (struct msgbuf __user *) ptr,
  				  second, third);
  	case MSGRCV:
  		switch (version) {
  		case 0: {
  			struct ipc_kludge tmp;
  			if (!ptr)
  				return -EINVAL;
  
  			if (copy_from_user(&tmp,
  					   (struct ipc_kludge __user *) ptr,
  					   sizeof(tmp)))
  				return -EFAULT;
  			return sys_msgrcv(first, tmp.msgp, second,
  					   tmp.msgtyp, third);
  		}
  		default:
  			return sys_msgrcv(first,
  					   (struct msgbuf __user *) ptr,
  					   second, fifth, third);
  		}
  	case MSGGET:
  		return sys_msgget((key_t) first, second);
  	case MSGCTL:
  		return sys_msgctl(first, second, (struct msqid_ds __user *)ptr);
  
  	case SHMAT:
  		switch (version) {
  		default: {
  			unsigned long raddr;
  			ret = do_shmat(first, (char __user *)ptr,

  				       second, &raddr, SHMLBA);

  			if (ret)
  				return ret;
  			return put_user(raddr, (unsigned long __user *) third);
  		}
  		case 1:
  			/*
  			 * This was the entry point for kernel-originating calls
  			 * from iBCS2 in 2.2 days.
  			 */
  			return -EINVAL;
  		}
  	case SHMDT:
  		return sys_shmdt((char __user *)ptr);
  	case SHMGET:
  		return sys_shmget(first, second, third);
  	case SHMCTL:
  		return sys_shmctl(first, second,
  				   (struct shmid_ds __user *) ptr);
  	default:
  		return -ENOSYS;
  	}
  }
  #endif

  
  #ifdef CONFIG_COMPAT
  #include <linux/compat.h>
  
  #ifndef COMPAT_SHMLBA
  #define COMPAT_SHMLBA	SHMLBA
  #endif
  
  struct compat_ipc_kludge {
  	compat_uptr_t msgp;
  	compat_long_t msgtyp;
  };
  
  #ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
  COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
  	u32, third, compat_uptr_t, ptr, u32, fifth)
  {
  	int version;
  	u32 pad;
  
  	version = call >> 16; /* hack for backward compatibility */
  	call &= 0xffff;
  
  	switch (call) {
  	case SEMOP:
  		/* struct sembuf is the same on 32 and 64bit :)) */
  		return sys_semtimedop(first, compat_ptr(ptr), second, NULL);
  	case SEMTIMEDOP:
  		return compat_sys_semtimedop(first, compat_ptr(ptr), second,
  						compat_ptr(fifth));
  	case SEMGET:
  		return sys_semget(first, second, third);
  	case SEMCTL:
  		if (!ptr)
  			return -EINVAL;
  		if (get_user(pad, (u32 __user *) compat_ptr(ptr)))
  			return -EFAULT;
  		return compat_sys_semctl(first, second, third, pad);
  
  	case MSGSND:
  		return compat_sys_msgsnd(first, ptr, second, third);
  
  	case MSGRCV: {
  		void __user *uptr = compat_ptr(ptr);
  
  		if (first < 0 || second < 0)
  			return -EINVAL;
  
  		if (!version) {
  			struct compat_ipc_kludge ipck;
  			if (!uptr)
  				return -EINVAL;
  			if (copy_from_user(&ipck, uptr, sizeof(ipck)))
  				return -EFAULT;
  			return compat_sys_msgrcv(first, ipck.msgp, second,
  						 ipck.msgtyp, third);
  		}
  		return compat_sys_msgrcv(first, ptr, second, fifth, third);
  	}
  	case MSGGET:
  		return sys_msgget(first, second);
  	case MSGCTL:
  		return compat_sys_msgctl(first, second, compat_ptr(ptr));
  
  	case SHMAT: {
  		int err;
  		unsigned long raddr;
  
  		if (version == 1)
  			return -EINVAL;
  		err = do_shmat(first, compat_ptr(ptr), second, &raddr,
  			       COMPAT_SHMLBA);
  		if (err < 0)
  			return err;
  		return put_user(raddr, (compat_ulong_t *)compat_ptr(third));
  	}
  	case SHMDT:
  		return sys_shmdt(compat_ptr(ptr));
  	case SHMGET:
  		return sys_shmget(first, (unsigned)second, third);
  	case SHMCTL:
  		return compat_sys_shmctl(first, second, compat_ptr(ptr));
  	}
  
  	return -ENOSYS;
  }
  #endif
  #endif