Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide
[sfrench/cifs-2.6.git] / ipc / syscall.c
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
20 int 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) || !IS_ENABLED(CONFIG_64BIT_TIME))
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
110 SYSCALL_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
124 struct compat_ipc_kludge {
125         compat_uptr_t msgp;
126         compat_long_t msgtyp;
127 };
128
129 #ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC
130 int 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
205 COMPAT_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