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author | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
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committer | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
commit | 849369d6c66d3054688672f97d31fceb8e8230fb (patch) | |
tree | 6135abc790ca67dedbe07c39806591e70eda81ce /ipc/msgutil.c | |
download | linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.gz linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.bz2 linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.zip |
initial_commit
Diffstat (limited to 'ipc/msgutil.c')
-rw-r--r-- | ipc/msgutil.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/ipc/msgutil.c b/ipc/msgutil.c new file mode 100644 index 00000000..8b5ce5d3 --- /dev/null +++ b/ipc/msgutil.c @@ -0,0 +1,147 @@ +/* + * linux/ipc/msgutil.c + * Copyright (C) 1999, 2004 Manfred Spraul + * + * This file is released under GNU General Public Licence version 2 or + * (at your option) any later version. + * + * See the file COPYING for more details. + */ + +#include <linux/spinlock.h> +#include <linux/init.h> +#include <linux/security.h> +#include <linux/slab.h> +#include <linux/ipc.h> +#include <linux/ipc_namespace.h> +#include <asm/uaccess.h> + +#include "util.h" + +DEFINE_SPINLOCK(mq_lock); + +/* + * The next 2 defines are here bc this is the only file + * compiled when either CONFIG_SYSVIPC and CONFIG_POSIX_MQUEUE + * and not CONFIG_IPC_NS. + */ +struct ipc_namespace init_ipc_ns = { + .count = ATOMIC_INIT(1), +#ifdef CONFIG_POSIX_MQUEUE + .mq_queues_max = DFLT_QUEUESMAX, + .mq_msg_max = DFLT_MSGMAX, + .mq_msgsize_max = DFLT_MSGSIZEMAX, +#endif + .user_ns = &init_user_ns, +}; + +atomic_t nr_ipc_ns = ATOMIC_INIT(1); + +struct msg_msgseg { + struct msg_msgseg* next; + /* the next part of the message follows immediately */ +}; + +#define DATALEN_MSG (PAGE_SIZE-sizeof(struct msg_msg)) +#define DATALEN_SEG (PAGE_SIZE-sizeof(struct msg_msgseg)) + +struct msg_msg *load_msg(const void __user *src, int len) +{ + struct msg_msg *msg; + struct msg_msgseg **pseg; + int err; + int alen; + + alen = len; + if (alen > DATALEN_MSG) + alen = DATALEN_MSG; + + msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL); + if (msg == NULL) + return ERR_PTR(-ENOMEM); + + msg->next = NULL; + msg->security = NULL; + + if (copy_from_user(msg + 1, src, alen)) { + err = -EFAULT; + goto out_err; + } + + len -= alen; + src = ((char __user *)src) + alen; + pseg = &msg->next; + while (len > 0) { + struct msg_msgseg *seg; + alen = len; + if (alen > DATALEN_SEG) + alen = DATALEN_SEG; + seg = kmalloc(sizeof(*seg) + alen, + GFP_KERNEL); + if (seg == NULL) { + err = -ENOMEM; + goto out_err; + } + *pseg = seg; + seg->next = NULL; + if (copy_from_user(seg + 1, src, alen)) { + err = -EFAULT; + goto out_err; + } + pseg = &seg->next; + len -= alen; + src = ((char __user *)src) + alen; + } + + err = security_msg_msg_alloc(msg); + if (err) + goto out_err; + + return msg; + +out_err: + free_msg(msg); + return ERR_PTR(err); +} + +int store_msg(void __user *dest, struct msg_msg *msg, int len) +{ + int alen; + struct msg_msgseg *seg; + + alen = len; + if (alen > DATALEN_MSG) + alen = DATALEN_MSG; + if (copy_to_user(dest, msg + 1, alen)) + return -1; + + len -= alen; + dest = ((char __user *)dest) + alen; + seg = msg->next; + while (len > 0) { + alen = len; + if (alen > DATALEN_SEG) + alen = DATALEN_SEG; + if (copy_to_user(dest, seg + 1, alen)) + return -1; + len -= alen; + dest = ((char __user *)dest) + alen; + seg = seg->next; + } + return 0; +} + +void free_msg(struct msg_msg *msg) +{ + struct msg_msgseg *seg; + + security_msg_msg_free(msg); + + seg = msg->next; + kfree(msg); + while (seg != NULL) { + struct msg_msgseg *tmp = seg->next; + kfree(seg); + seg = tmp; + } +} |