syscall.c 4.33 KB
Newer Older
1
// SPDX-License-Identifier: GPL-2.0
2 3 4 5 6 7 8
/*
 * 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>
Al Viro's avatar
Al Viro committed
9
#include <linux/syscalls.h>
10 11 12 13 14 15 16

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

17
SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
		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: {
37
		unsigned long arg;
38 39
		if (!ptr)
			return -EINVAL;
40
		if (get_user(arg, (unsigned long __user *) ptr))
41
			return -EFAULT;
42
		return sys_semctl(first, second, third, arg);
43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76
	}

	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,
77
				       second, &raddr, SHMLBA);
78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100
			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
Al Viro's avatar
Al Viro committed
101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188

#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