Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
f30c2269 | 2 | * linux/ipc/msgutil.c |
1da177e4 LT |
3 | * Copyright (C) 1999, 2004 Manfred Spraul |
4 | * | |
5 | * This file is released under GNU General Public Licence version 2 or | |
6 | * (at your option) any later version. | |
7 | * | |
8 | * See the file COPYING for more details. | |
9 | */ | |
10 | ||
11 | #include <linux/spinlock.h> | |
12 | #include <linux/init.h> | |
13 | #include <linux/security.h> | |
14 | #include <linux/slab.h> | |
15 | #include <linux/ipc.h> | |
40401530 | 16 | #include <linux/msg.h> |
614b84cf | 17 | #include <linux/ipc_namespace.h> |
40401530 | 18 | #include <linux/utsname.h> |
98f842e6 | 19 | #include <linux/proc_fs.h> |
1da177e4 LT |
20 | #include <asm/uaccess.h> |
21 | ||
22 | #include "util.h" | |
23 | ||
7eafd7c7 SH |
24 | DEFINE_SPINLOCK(mq_lock); |
25 | ||
614b84cf SH |
26 | /* |
27 | * The next 2 defines are here bc this is the only file | |
28 | * compiled when either CONFIG_SYSVIPC and CONFIG_POSIX_MQUEUE | |
29 | * and not CONFIG_IPC_NS. | |
30 | */ | |
31 | struct ipc_namespace init_ipc_ns = { | |
7eafd7c7 | 32 | .count = ATOMIC_INIT(1), |
b515498f | 33 | .user_ns = &init_user_ns, |
98f842e6 | 34 | .proc_inum = PROC_IPC_INIT_INO, |
614b84cf SH |
35 | }; |
36 | ||
37 | atomic_t nr_ipc_ns = ATOMIC_INIT(1); | |
38 | ||
1da177e4 LT |
39 | struct msg_msgseg { |
40 | struct msg_msgseg* next; | |
41 | /* the next part of the message follows immediately */ | |
42 | }; | |
43 | ||
44 | #define DATALEN_MSG (PAGE_SIZE-sizeof(struct msg_msg)) | |
45 | #define DATALEN_SEG (PAGE_SIZE-sizeof(struct msg_msgseg)) | |
46 | ||
47 | struct msg_msg *load_msg(const void __user *src, int len) | |
48 | { | |
49 | struct msg_msg *msg; | |
50 | struct msg_msgseg **pseg; | |
51 | int err; | |
52 | int alen; | |
53 | ||
54 | alen = len; | |
55 | if (alen > DATALEN_MSG) | |
56 | alen = DATALEN_MSG; | |
57 | ||
5cbded58 | 58 | msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL); |
1da177e4 LT |
59 | if (msg == NULL) |
60 | return ERR_PTR(-ENOMEM); | |
61 | ||
62 | msg->next = NULL; | |
63 | msg->security = NULL; | |
64 | ||
65 | if (copy_from_user(msg + 1, src, alen)) { | |
66 | err = -EFAULT; | |
67 | goto out_err; | |
68 | } | |
69 | ||
70 | len -= alen; | |
71 | src = ((char __user *)src) + alen; | |
72 | pseg = &msg->next; | |
73 | while (len > 0) { | |
74 | struct msg_msgseg *seg; | |
75 | alen = len; | |
76 | if (alen > DATALEN_SEG) | |
77 | alen = DATALEN_SEG; | |
5cbded58 | 78 | seg = kmalloc(sizeof(*seg) + alen, |
1da177e4 LT |
79 | GFP_KERNEL); |
80 | if (seg == NULL) { | |
81 | err = -ENOMEM; | |
82 | goto out_err; | |
83 | } | |
84 | *pseg = seg; | |
85 | seg->next = NULL; | |
86 | if (copy_from_user(seg + 1, src, alen)) { | |
87 | err = -EFAULT; | |
88 | goto out_err; | |
89 | } | |
90 | pseg = &seg->next; | |
91 | len -= alen; | |
92 | src = ((char __user *)src) + alen; | |
93 | } | |
94 | ||
95 | err = security_msg_msg_alloc(msg); | |
96 | if (err) | |
97 | goto out_err; | |
98 | ||
99 | return msg; | |
100 | ||
101 | out_err: | |
102 | free_msg(msg); | |
103 | return ERR_PTR(err); | |
104 | } | |
4a674f34 SK |
105 | #ifdef CONFIG_CHECKPOINT_RESTORE |
106 | struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst) | |
107 | { | |
108 | struct msg_msgseg *dst_pseg, *src_pseg; | |
109 | int len = src->m_ts; | |
110 | int alen; | |
111 | ||
112 | BUG_ON(dst == NULL); | |
113 | if (src->m_ts > dst->m_ts) | |
114 | return ERR_PTR(-EINVAL); | |
115 | ||
116 | alen = len; | |
117 | if (alen > DATALEN_MSG) | |
118 | alen = DATALEN_MSG; | |
119 | ||
4a674f34 SK |
120 | memcpy(dst + 1, src + 1, alen); |
121 | ||
122 | len -= alen; | |
123 | dst_pseg = dst->next; | |
124 | src_pseg = src->next; | |
125 | while (len > 0) { | |
126 | alen = len; | |
127 | if (alen > DATALEN_SEG) | |
128 | alen = DATALEN_SEG; | |
129 | memcpy(dst_pseg + 1, src_pseg + 1, alen); | |
130 | dst_pseg = dst_pseg->next; | |
131 | len -= alen; | |
132 | src_pseg = src_pseg->next; | |
133 | } | |
134 | ||
135 | dst->m_type = src->m_type; | |
136 | dst->m_ts = src->m_ts; | |
137 | ||
138 | return dst; | |
139 | } | |
51eeacaa SK |
140 | #else |
141 | struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst) | |
142 | { | |
143 | return ERR_PTR(-ENOSYS); | |
144 | } | |
4a674f34 | 145 | #endif |
1da177e4 LT |
146 | int store_msg(void __user *dest, struct msg_msg *msg, int len) |
147 | { | |
148 | int alen; | |
149 | struct msg_msgseg *seg; | |
150 | ||
151 | alen = len; | |
152 | if (alen > DATALEN_MSG) | |
153 | alen = DATALEN_MSG; | |
154 | if (copy_to_user(dest, msg + 1, alen)) | |
155 | return -1; | |
156 | ||
157 | len -= alen; | |
158 | dest = ((char __user *)dest) + alen; | |
159 | seg = msg->next; | |
160 | while (len > 0) { | |
161 | alen = len; | |
162 | if (alen > DATALEN_SEG) | |
163 | alen = DATALEN_SEG; | |
164 | if (copy_to_user(dest, seg + 1, alen)) | |
165 | return -1; | |
166 | len -= alen; | |
167 | dest = ((char __user *)dest) + alen; | |
168 | seg = seg->next; | |
169 | } | |
170 | return 0; | |
171 | } | |
172 | ||
173 | void free_msg(struct msg_msg *msg) | |
174 | { | |
175 | struct msg_msgseg *seg; | |
176 | ||
177 | security_msg_msg_free(msg); | |
178 | ||
179 | seg = msg->next; | |
180 | kfree(msg); | |
181 | while (seg != NULL) { | |
182 | struct msg_msgseg *tmp = seg->next; | |
183 | kfree(seg); | |
184 | seg = tmp; | |
185 | } | |
186 | } |