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 11 #ifdef __ARCH_WANT_SYS_IPC 12 #include <linux/errno.h> 13 #include <linux/ipc.h> 14 #include <linux/shm.h> 15 #include <linux/uaccess.h> 16 17 SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second, 18 unsigned long, third, void __user *, ptr, long, fifth) 19 { 20 int version, ret; 21 22 version = call >> 16; /* hack for backward compatibility */ 23 call &= 0xffff; 24 25 switch (call) { 26 case SEMOP: 27 return sys_semtimedop(first, (struct sembuf __user *)ptr, 28 second, NULL); 29 case SEMTIMEDOP: 30 return sys_semtimedop(first, (struct sembuf __user *)ptr, 31 second, 32 (const struct timespec __user *)fifth); 33 34 case SEMGET: 35 return sys_semget(first, second, third); 36 case SEMCTL: { 37 unsigned long arg; 38 if (!ptr) 39 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 case MSGSND: 46 return sys_msgsnd(first, (struct msgbuf __user *) ptr, 47 second, third); 48 case MSGRCV: 49 switch (version) { 50 case 0: { 51 struct ipc_kludge tmp; 52 if (!ptr) 53 return -EINVAL; 54 55 if (copy_from_user(&tmp, 56 (struct ipc_kludge __user *) ptr, 57 sizeof(tmp))) 58 return -EFAULT; 59 return sys_msgrcv(first, tmp.msgp, second, 60 tmp.msgtyp, third); 61 } 62 default: 63 return sys_msgrcv(first, 64 (struct msgbuf __user *) ptr, 65 second, fifth, third); 66 } 67 case MSGGET: 68 return sys_msgget((key_t) first, second); 69 case MSGCTL: 70 return sys_msgctl(first, second, (struct msqid_ds __user *)ptr); 71 72 case SHMAT: 73 switch (version) { 74 default: { 75 unsigned long raddr; 76 ret = do_shmat(first, (char __user *)ptr, 77 second, &raddr, SHMLBA); 78 if (ret) 79 return ret; 80 return put_user(raddr, (unsigned long __user *) third); 81 } 82 case 1: 83 /* 84 * This was the entry point for kernel-originating calls 85 * from iBCS2 in 2.2 days. 86 */ 87 return -EINVAL; 88 } 89 case SHMDT: 90 return sys_shmdt((char __user *)ptr); 91 case SHMGET: 92 return sys_shmget(first, second, third); 93 case SHMCTL: 94 return sys_shmctl(first, second, 95 (struct shmid_ds __user *) ptr); 96 default: 97 return -ENOSYS; 98 } 99 } 100 #endif 101 102 #ifdef CONFIG_COMPAT 103 #include <linux/compat.h> 104 105 #ifndef COMPAT_SHMLBA 106 #define COMPAT_SHMLBA SHMLBA 107 #endif 108 109 struct compat_ipc_kludge { 110 compat_uptr_t msgp; 111 compat_long_t msgtyp; 112 }; 113 114 #ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC 115 COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second, 116 u32, third, compat_uptr_t, ptr, u32, fifth) 117 { 118 int version; 119 u32 pad; 120 121 version = call >> 16; /* hack for backward compatibility */ 122 call &= 0xffff; 123 124 switch (call) { 125 case SEMOP: 126 /* struct sembuf is the same on 32 and 64bit :)) */ 127 return sys_semtimedop(first, compat_ptr(ptr), second, NULL); 128 case SEMTIMEDOP: 129 return compat_sys_semtimedop(first, compat_ptr(ptr), second, 130 compat_ptr(fifth)); 131 case SEMGET: 132 return sys_semget(first, second, third); 133 case SEMCTL: 134 if (!ptr) 135 return -EINVAL; 136 if (get_user(pad, (u32 __user *) compat_ptr(ptr))) 137 return -EFAULT; 138 return compat_sys_semctl(first, second, third, pad); 139 140 case MSGSND: 141 return compat_sys_msgsnd(first, ptr, second, third); 142 143 case MSGRCV: { 144 void __user *uptr = compat_ptr(ptr); 145 146 if (first < 0 || second < 0) 147 return -EINVAL; 148 149 if (!version) { 150 struct compat_ipc_kludge ipck; 151 if (!uptr) 152 return -EINVAL; 153 if (copy_from_user(&ipck, uptr, sizeof(ipck))) 154 return -EFAULT; 155 return compat_sys_msgrcv(first, ipck.msgp, second, 156 ipck.msgtyp, third); 157 } 158 return compat_sys_msgrcv(first, ptr, second, fifth, third); 159 } 160 case MSGGET: 161 return sys_msgget(first, second); 162 case MSGCTL: 163 return compat_sys_msgctl(first, second, compat_ptr(ptr)); 164 165 case SHMAT: { 166 int err; 167 unsigned long raddr; 168 169 if (version == 1) 170 return -EINVAL; 171 err = do_shmat(first, compat_ptr(ptr), second, &raddr, 172 COMPAT_SHMLBA); 173 if (err < 0) 174 return err; 175 return put_user(raddr, (compat_ulong_t __user *)compat_ptr(third)); 176 } 177 case SHMDT: 178 return sys_shmdt(compat_ptr(ptr)); 179 case SHMGET: 180 return sys_shmget(first, (unsigned)second, third); 181 case SHMCTL: 182 return compat_sys_shmctl(first, second, compat_ptr(ptr)); 183 } 184 185 return -ENOSYS; 186 } 187 #endif 188 #endif 189