1/* 2 * ipc/compat_mq.c 3 * 32 bit emulation for POSIX message queue system calls 4 * 5 * Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation 6 * Author: Arnd Bergmann <arnd@arndb.de> 7 */ 8 9#include <linux/compat.h> 10#include <linux/fs.h> 11#include <linux/kernel.h> 12#include <linux/mqueue.h> 13#include <linux/syscalls.h> 14 15#include <asm/uaccess.h> 16 17struct compat_mq_attr { 18 compat_long_t mq_flags; /* message queue flags */ 19 compat_long_t mq_maxmsg; /* maximum number of messages */ 20 compat_long_t mq_msgsize; /* maximum message size */ 21 compat_long_t mq_curmsgs; /* number of messages currently queued */ 22 compat_long_t __reserved[4]; /* ignored for input, zeroed for output */ 23}; 24 25static inline int get_compat_mq_attr(struct mq_attr *attr, 26 const struct compat_mq_attr __user *uattr) 27{ 28 if (!access_ok(VERIFY_READ, uattr, sizeof *uattr)) 29 return -EFAULT; 30 31 return __get_user(attr->mq_flags, &uattr->mq_flags) 32 | __get_user(attr->mq_maxmsg, &uattr->mq_maxmsg) 33 | __get_user(attr->mq_msgsize, &uattr->mq_msgsize) 34 | __get_user(attr->mq_curmsgs, &uattr->mq_curmsgs); 35} 36 37static inline int put_compat_mq_attr(const struct mq_attr *attr, 38 struct compat_mq_attr __user *uattr) 39{ 40 if (clear_user(uattr, sizeof *uattr)) 41 return -EFAULT; 42 43 return __put_user(attr->mq_flags, &uattr->mq_flags) 44 | __put_user(attr->mq_maxmsg, &uattr->mq_maxmsg) 45 | __put_user(attr->mq_msgsize, &uattr->mq_msgsize) 46 | __put_user(attr->mq_curmsgs, &uattr->mq_curmsgs); 47} 48 49asmlinkage long compat_sys_mq_open(const char __user *u_name, 50 int oflag, compat_mode_t mode, 51 struct compat_mq_attr __user *u_attr) 52{ 53 void __user *p = NULL; 54 if (u_attr && oflag & O_CREAT) { 55 struct mq_attr attr; 56 57 memset(&attr, 0, sizeof(attr)); 58 59 p = compat_alloc_user_space(sizeof(attr)); 60 if (get_compat_mq_attr(&attr, u_attr) || 61 copy_to_user(p, &attr, sizeof(attr))) 62 return -EFAULT; 63 } 64 return sys_mq_open(u_name, oflag, mode, p); 65} 66 67static int compat_prepare_timeout(struct timespec __user * *p, 68 const struct compat_timespec __user *u) 69{ 70 struct timespec ts; 71 if (!u) { 72 *p = NULL; 73 return 0; 74 } 75 *p = compat_alloc_user_space(sizeof(ts)); 76 if (get_compat_timespec(&ts, u) || copy_to_user(*p, &ts, sizeof(ts))) 77 return -EFAULT; 78 return 0; 79} 80 81asmlinkage long compat_sys_mq_timedsend(mqd_t mqdes, 82 const char __user *u_msg_ptr, 83 size_t msg_len, unsigned int msg_prio, 84 const struct compat_timespec __user *u_abs_timeout) 85{ 86 struct timespec __user *u_ts; 87 88 if (compat_prepare_timeout(&u_ts, u_abs_timeout)) 89 return -EFAULT; 90 91 return sys_mq_timedsend(mqdes, u_msg_ptr, msg_len, 92 msg_prio, u_ts); 93} 94 95asmlinkage ssize_t compat_sys_mq_timedreceive(mqd_t mqdes, 96 char __user *u_msg_ptr, 97 size_t msg_len, unsigned int __user *u_msg_prio, 98 const struct compat_timespec __user *u_abs_timeout) 99{ 100 struct timespec __user *u_ts; 101 if (compat_prepare_timeout(&u_ts, u_abs_timeout)) 102 return -EFAULT; 103 104 return sys_mq_timedreceive(mqdes, u_msg_ptr, msg_len, 105 u_msg_prio, u_ts); 106} 107 108asmlinkage long compat_sys_mq_notify(mqd_t mqdes, 109 const struct compat_sigevent __user *u_notification) 110{ 111 struct sigevent __user *p = NULL; 112 if (u_notification) { 113 struct sigevent n; 114 p = compat_alloc_user_space(sizeof(*p)); 115 if (get_compat_sigevent(&n, u_notification)) 116 return -EFAULT; 117 if (n.sigev_notify == SIGEV_THREAD) 118 n.sigev_value.sival_ptr = compat_ptr(n.sigev_value.sival_int); 119 if (copy_to_user(p, &n, sizeof(*p))) 120 return -EFAULT; 121 } 122 return sys_mq_notify(mqdes, p); 123} 124 125asmlinkage long compat_sys_mq_getsetattr(mqd_t mqdes, 126 const struct compat_mq_attr __user *u_mqstat, 127 struct compat_mq_attr __user *u_omqstat) 128{ 129 struct mq_attr mqstat; 130 struct mq_attr __user *p = compat_alloc_user_space(2 * sizeof(*p)); 131 long ret; 132 133 memset(&mqstat, 0, sizeof(mqstat)); 134 135 if (u_mqstat) { 136 if (get_compat_mq_attr(&mqstat, u_mqstat) || 137 copy_to_user(p, &mqstat, sizeof(mqstat))) 138 return -EFAULT; 139 } 140 ret = sys_mq_getsetattr(mqdes, 141 u_mqstat ? p : NULL, 142 u_omqstat ? p + 1 : NULL); 143 if (ret) 144 return ret; 145 if (u_omqstat) { 146 if (copy_from_user(&mqstat, p + 1, sizeof(mqstat)) || 147 put_compat_mq_attr(&mqstat, u_omqstat)) 148 return -EFAULT; 149 } 150 return 0; 151} 152