projects/linux·blob 2c455ddc · refs

211 lines · 5.1 KiB

1// SPDX-License-Identifier: GPL-2.0
2/*
3 * sys_ipc() is the old de-multiplexer for the SysV IPC calls.
4 *
5 * This is really horribly ugly, and new architectures should just wire up
6 * the individual syscalls instead.
7 */
8#include <linux/unistd.h>
9#include <linux/syscalls.h>
10#include <linux/security.h>
11#include <linux/ipc_namespace.h>
12#include "util.h"
13
14#ifdef __ARCH_WANT_SYS_IPC
15#include <linux/errno.h>
16#include <linux/ipc.h>
17#include <linux/shm.h>
18#include <linux/uaccess.h>
19
20int ksys_ipc(unsigned int call, int first, unsigned long second,
21 unsigned long third, void __user * ptr, long fifth)
22{
23 int version, ret;
24
25 version = call >> 16; /* hack for backward compatibility */
26 call &= 0xffff;
27
28 switch (call) {
29 case SEMOP:
30 return ksys_semtimedop(first, (struct sembuf __user *)ptr,
31 second, NULL);
32 case SEMTIMEDOP:
33 if (IS_ENABLED(CONFIG_64BIT))
34 return ksys_semtimedop(first, ptr, second,
35 (const struct __kernel_timespec __user *)fifth);
36 else if (IS_ENABLED(CONFIG_COMPAT_32BIT_TIME))
37 return compat_ksys_semtimedop(first, ptr, second,
38 (const struct old_timespec32 __user *)fifth);
39 else
40 return -ENOSYS;
41
42 case SEMGET:
43 return ksys_semget(first, second, third);
44 case SEMCTL: {
45 unsigned long arg;
46 if (!ptr)
47 return -EINVAL;
48 if (get_user(arg, (unsigned long __user *) ptr))
49 return -EFAULT;
50 return ksys_old_semctl(first, second, third, arg);
51 }
52
53 case MSGSND:
54 return ksys_msgsnd(first, (struct msgbuf __user *) ptr,
55 second, third);
56 case MSGRCV:
57 switch (version) {
58 case 0: {
59 struct ipc_kludge tmp;
60 if (!ptr)
61 return -EINVAL;
62
63 if (copy_from_user(&tmp,
64 (struct ipc_kludge __user *) ptr,
65 sizeof(tmp)))
66 return -EFAULT;
67 return ksys_msgrcv(first, tmp.msgp, second,
68 tmp.msgtyp, third);
69 }
70 default:
71 return ksys_msgrcv(first,
72 (struct msgbuf __user *) ptr,
73 second, fifth, third);
74 }
75 case MSGGET:
76 return ksys_msgget((key_t) first, second);
77 case MSGCTL:
78 return ksys_old_msgctl(first, second,
79 (struct msqid_ds __user *)ptr);
80
81 case SHMAT:
82 switch (version) {
83 default: {
84 unsigned long raddr;
85 ret = do_shmat(first, (char __user *)ptr,
86 second, &raddr, SHMLBA);
87 if (ret)
88 return ret;
89 return put_user(raddr, (unsigned long __user *) third);
90 }
91 case 1:
92 /*
93 * This was the entry point for kernel-originating calls
94 * from iBCS2 in 2.2 days.
95 */
96 return -EINVAL;
97 }
98 case SHMDT:
99 return ksys_shmdt((char __user *)ptr);
100 case SHMGET:
101 return ksys_shmget(first, second, third);
102 case SHMCTL:
103 return ksys_old_shmctl(first, second,
104 (struct shmid_ds __user *) ptr);
105 default:
106 return -ENOSYS;
107 }
108}
109
110SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second,
111 unsigned long, third, void __user *, ptr, long, fifth)
112{
113 return ksys_ipc(call, first, second, third, ptr, fifth);
114}
115#endif
116
117#ifdef CONFIG_COMPAT
118#include <linux/compat.h>
119
120#ifndef COMPAT_SHMLBA
121#define COMPAT_SHMLBA SHMLBA
122#endif
123
124struct compat_ipc_kludge {
125 compat_uptr_t msgp;
126 compat_long_t msgtyp;
127};
128
129#ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
130int compat_ksys_ipc(u32 call, int first, int second,
131 u32 third, compat_uptr_t ptr, u32 fifth)
132{
133 int version;
134 u32 pad;
135
136 version = call >> 16; /* hack for backward compatibility */
137 call &= 0xffff;
138
139 switch (call) {
140 case SEMOP:
141 /* struct sembuf is the same on 32 and 64bit :)) */
142 return ksys_semtimedop(first, compat_ptr(ptr), second, NULL);
143 case SEMTIMEDOP:
144 if (!IS_ENABLED(CONFIG_COMPAT_32BIT_TIME))
145 return -ENOSYS;
146 return compat_ksys_semtimedop(first, compat_ptr(ptr), second,
147 compat_ptr(fifth));
148 case SEMGET:
149 return ksys_semget(first, second, third);
150 case SEMCTL:
151 if (!ptr)
152 return -EINVAL;
153 if (get_user(pad, (u32 __user *) compat_ptr(ptr)))
154 return -EFAULT;
155 return compat_ksys_old_semctl(first, second, third, pad);
156
157 case MSGSND:
158 return compat_ksys_msgsnd(first, ptr, second, third);
159
160 case MSGRCV: {
161 void __user *uptr = compat_ptr(ptr);
162
163 if (first < 0 || second < 0)
164 return -EINVAL;
165
166 if (!version) {
167 struct compat_ipc_kludge ipck;
168 if (!uptr)
169 return -EINVAL;
170 if (copy_from_user(&ipck, uptr, sizeof(ipck)))
171 return -EFAULT;
172 return compat_ksys_msgrcv(first, ipck.msgp, second,
173 ipck.msgtyp, third);
174 }
175 return compat_ksys_msgrcv(first, ptr, second, fifth, third);
176 }
177 case MSGGET:
178 return ksys_msgget(first, second);
179 case MSGCTL:
180 return compat_ksys_old_msgctl(first, second, compat_ptr(ptr));
181
182 case SHMAT: {
183 int err;
184 unsigned long raddr;
185
186 if (version == 1)
187 return -EINVAL;
188 err = do_shmat(first, compat_ptr(ptr), second, &raddr,
189 COMPAT_SHMLBA);
190 if (err < 0)
191 return err;
192 return put_user(raddr, (compat_ulong_t __user *)compat_ptr(third));
193 }
194 case SHMDT:
195 return ksys_shmdt(compat_ptr(ptr));
196 case SHMGET:
197 return ksys_shmget(first, (unsigned int)second, third);
198 case SHMCTL:
199 return compat_ksys_old_shmctl(first, second, compat_ptr(ptr));
200 }
201
202 return -ENOSYS;
203}
204
205COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
206 u32, third, compat_uptr_t, ptr, u32, fifth)
207{
208 return compat_ksys_ipc(call, first, second, third, ptr, fifth);
209}
210#endif
211#endif