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)) |
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(semid: first, tsops: compat_ptr(uptr: ptr), nsops: second, NULL); |
143 | case SEMTIMEDOP: |
144 | if (!IS_ENABLED(CONFIG_COMPAT_32BIT_TIME)) |
145 | return -ENOSYS; |
146 | return compat_ksys_semtimedop(semid: first, tsems: compat_ptr(uptr: ptr), nsops: second, |
147 | timeout: compat_ptr(uptr: fifth)); |
148 | case SEMGET: |
149 | return ksys_semget(key: first, nsems: second, semflg: 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(semid: first, semnum: second, cmd: third, arg: pad); |
156 | |
157 | case MSGSND: |
158 | return compat_ksys_msgsnd(msqid: first, msgp: ptr, msgsz: second, msgflg: third); |
159 | |
160 | case MSGRCV: { |
161 | void __user *uptr = compat_ptr(uptr: 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(to: &ipck, from: uptr, n: sizeof(ipck))) |
171 | return -EFAULT; |
172 | return compat_ksys_msgrcv(msqid: first, msgp: ipck.msgp, msgsz: second, |
173 | msgtyp: ipck.msgtyp, msgflg: third); |
174 | } |
175 | return compat_ksys_msgrcv(msqid: first, msgp: ptr, msgsz: second, msgtyp: fifth, msgflg: third); |
176 | } |
177 | case MSGGET: |
178 | return ksys_msgget(key: first, msgflg: second); |
179 | case MSGCTL: |
180 | return compat_ksys_old_msgctl(msqid: first, cmd: second, uptr: compat_ptr(uptr: ptr)); |
181 | |
182 | case SHMAT: { |
183 | int err; |
184 | unsigned long raddr; |
185 | |
186 | if (version == 1) |
187 | return -EINVAL; |
188 | err = do_shmat(shmid: first, shmaddr: compat_ptr(uptr: ptr), shmflg: second, addr: &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(shmaddr: compat_ptr(uptr: ptr)); |
196 | case SHMGET: |
197 | return ksys_shmget(key: first, size: (unsigned int)second, shmflg: third); |
198 | case SHMCTL: |
199 | return compat_ksys_old_shmctl(shmid: first, cmd: second, uptr: compat_ptr(uptr: 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 |
212 | |