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 | ||
3d8fa456 PH |
44 | #define DATALEN_MSG (int)(PAGE_SIZE-sizeof(struct msg_msg)) |
45 | #define DATALEN_SEG (int)(PAGE_SIZE-sizeof(struct msg_msgseg)) | |
1da177e4 | 46 | |
be5f4b33 PH |
47 | |
48 | static struct msg_msg *alloc_msg(int len) | |
1da177e4 LT |
49 | { |
50 | struct msg_msg *msg; | |
51 | struct msg_msgseg **pseg; | |
1da177e4 LT |
52 | int alen; |
53 | ||
3d8fa456 | 54 | alen = min(len, DATALEN_MSG); |
5cbded58 | 55 | msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL); |
1da177e4 | 56 | if (msg == NULL) |
be5f4b33 | 57 | return NULL; |
1da177e4 LT |
58 | |
59 | msg->next = NULL; | |
60 | msg->security = NULL; | |
61 | ||
be5f4b33 PH |
62 | len -= alen; |
63 | pseg = &msg->next; | |
64 | while (len > 0) { | |
65 | struct msg_msgseg *seg; | |
66 | alen = min(len, DATALEN_SEG); | |
67 | seg = kmalloc(sizeof(*seg) + alen, GFP_KERNEL); | |
68 | if (seg == NULL) | |
69 | goto out_err; | |
70 | *pseg = seg; | |
71 | seg->next = NULL; | |
72 | pseg = &seg->next; | |
73 | len -= alen; | |
74 | } | |
75 | ||
76 | return msg; | |
77 | ||
78 | out_err: | |
79 | free_msg(msg); | |
80 | return NULL; | |
81 | } | |
82 | ||
83 | struct msg_msg *load_msg(const void __user *src, int len) | |
84 | { | |
85 | struct msg_msg *msg; | |
86 | struct msg_msgseg *seg; | |
87 | int err; | |
88 | int alen; | |
89 | ||
90 | msg = alloc_msg(len); | |
91 | if (msg == NULL) | |
92 | return ERR_PTR(-ENOMEM); | |
93 | ||
94 | alen = min(len, DATALEN_MSG); | |
1da177e4 LT |
95 | if (copy_from_user(msg + 1, src, alen)) { |
96 | err = -EFAULT; | |
97 | goto out_err; | |
98 | } | |
99 | ||
100 | len -= alen; | |
101 | src = ((char __user *)src) + alen; | |
be5f4b33 | 102 | seg = msg->next; |
1da177e4 | 103 | while (len > 0) { |
3d8fa456 | 104 | alen = min(len, DATALEN_SEG); |
1da177e4 LT |
105 | if (copy_from_user(seg + 1, src, alen)) { |
106 | err = -EFAULT; | |
107 | goto out_err; | |
108 | } | |
be5f4b33 | 109 | seg = seg->next; |
1da177e4 LT |
110 | len -= alen; |
111 | src = ((char __user *)src) + alen; | |
112 | } | |
113 | ||
114 | err = security_msg_msg_alloc(msg); | |
115 | if (err) | |
116 | goto out_err; | |
117 | ||
118 | return msg; | |
119 | ||
120 | out_err: | |
121 | free_msg(msg); | |
122 | return ERR_PTR(err); | |
123 | } | |
4a674f34 SK |
124 | #ifdef CONFIG_CHECKPOINT_RESTORE |
125 | struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst) | |
126 | { | |
127 | struct msg_msgseg *dst_pseg, *src_pseg; | |
128 | int len = src->m_ts; | |
129 | int alen; | |
130 | ||
131 | BUG_ON(dst == NULL); | |
132 | if (src->m_ts > dst->m_ts) | |
133 | return ERR_PTR(-EINVAL); | |
134 | ||
3d8fa456 | 135 | alen = min(len, DATALEN_MSG); |
4a674f34 SK |
136 | memcpy(dst + 1, src + 1, alen); |
137 | ||
138 | len -= alen; | |
139 | dst_pseg = dst->next; | |
140 | src_pseg = src->next; | |
141 | while (len > 0) { | |
3d8fa456 | 142 | alen = min(len, DATALEN_SEG); |
4a674f34 SK |
143 | memcpy(dst_pseg + 1, src_pseg + 1, alen); |
144 | dst_pseg = dst_pseg->next; | |
145 | len -= alen; | |
146 | src_pseg = src_pseg->next; | |
147 | } | |
148 | ||
149 | dst->m_type = src->m_type; | |
150 | dst->m_ts = src->m_ts; | |
151 | ||
152 | return dst; | |
153 | } | |
51eeacaa SK |
154 | #else |
155 | struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst) | |
156 | { | |
157 | return ERR_PTR(-ENOSYS); | |
158 | } | |
4a674f34 | 159 | #endif |
1da177e4 LT |
160 | int store_msg(void __user *dest, struct msg_msg *msg, int len) |
161 | { | |
162 | int alen; | |
163 | struct msg_msgseg *seg; | |
164 | ||
3d8fa456 | 165 | alen = min(len, DATALEN_MSG); |
1da177e4 LT |
166 | if (copy_to_user(dest, msg + 1, alen)) |
167 | return -1; | |
168 | ||
169 | len -= alen; | |
170 | dest = ((char __user *)dest) + alen; | |
171 | seg = msg->next; | |
172 | while (len > 0) { | |
3d8fa456 | 173 | alen = min(len, DATALEN_SEG); |
1da177e4 LT |
174 | if (copy_to_user(dest, seg + 1, alen)) |
175 | return -1; | |
176 | len -= alen; | |
177 | dest = ((char __user *)dest) + alen; | |
178 | seg = seg->next; | |
179 | } | |
180 | return 0; | |
181 | } | |
182 | ||
183 | void free_msg(struct msg_msg *msg) | |
184 | { | |
185 | struct msg_msgseg *seg; | |
186 | ||
187 | security_msg_msg_free(msg); | |
188 | ||
189 | seg = msg->next; | |
190 | kfree(msg); | |
191 | while (seg != NULL) { | |
192 | struct msg_msgseg *tmp = seg->next; | |
193 | kfree(seg); | |
194 | seg = tmp; | |
195 | } | |
196 | } |