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Diffstat (limited to 'ipc/mqueue.c')
-rw-r--r--ipc/mqueue.c256
1 files changed, 129 insertions, 127 deletions
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 9167853..e35ba2c 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -31,6 +31,7 @@
#include <linux/mutex.h>
#include <linux/nsproxy.h>
#include <linux/pid.h>
+#include <linux/ipc_namespace.h>
#include <net/sock.h>
#include "util.h"
@@ -46,21 +47,6 @@
#define STATE_PENDING 1
#define STATE_READY 2
-/* default values */
-#define DFLT_QUEUESMAX 256 /* max number of message queues */
-#define DFLT_MSGMAX 10 /* max number of messages in each queue */
-#define HARD_MSGMAX (131072/sizeof(void*))
-#define DFLT_MSGSIZEMAX 8192 /* max message size */
-
-/*
- * Define the ranges various user-specified maximum values can
- * be set to.
- */
-#define MIN_MSGMAX 1 /* min value for msg_max */
-#define MAX_MSGMAX HARD_MSGMAX /* max value for msg_max */
-#define MIN_MSGSIZEMAX 128 /* min value for msgsize_max */
-#define MAX_MSGSIZEMAX (8192*128) /* max value for msgsize_max */
-
struct ext_wait_queue { /* queue of sleeping tasks */
struct task_struct *task;
struct list_head list;
@@ -93,14 +79,7 @@ static const struct file_operations mqueue_file_operations;
static struct super_operations mqueue_super_ops;
static void remove_notification(struct mqueue_inode_info *info);
-static spinlock_t mq_lock;
static struct kmem_cache *mqueue_inode_cachep;
-static struct vfsmount *mqueue_mnt;
-
-static unsigned int queues_count;
-static unsigned int queues_max = DFLT_QUEUESMAX;
-static unsigned int msg_max = DFLT_MSGMAX;
-static unsigned int msgsize_max = DFLT_MSGSIZEMAX;
static struct ctl_table_header * mq_sysctl_table;
@@ -109,8 +88,27 @@ static inline struct mqueue_inode_info *MQUEUE_I(struct inode *inode)
return container_of(inode, struct mqueue_inode_info, vfs_inode);
}
-static struct inode *mqueue_get_inode(struct super_block *sb, int mode,
- struct mq_attr *attr)
+/*
+ * This routine should be called with the mq_lock held.
+ */
+static inline struct ipc_namespace *__get_ns_from_inode(struct inode *inode)
+{
+ return get_ipc_ns(inode->i_sb->s_fs_info);
+}
+
+static struct ipc_namespace *get_ns_from_inode(struct inode *inode)
+{
+ struct ipc_namespace *ns;
+
+ spin_lock(&mq_lock);
+ ns = __get_ns_from_inode(inode);
+ spin_unlock(&mq_lock);
+ return ns;
+}
+
+static struct inode *mqueue_get_inode(struct super_block *sb,
+ struct ipc_namespace *ipc_ns, int mode,
+ struct mq_attr *attr)
{
struct user_struct *u = current_user();
struct inode *inode;
@@ -141,8 +139,8 @@ static struct inode *mqueue_get_inode(struct super_block *sb, int mode,
info->qsize = 0;
info->user = NULL; /* set when all is ok */
memset(&info->attr, 0, sizeof(info->attr));
- info->attr.mq_maxmsg = msg_max;
- info->attr.mq_msgsize = msgsize_max;
+ info->attr.mq_maxmsg = ipc_ns->mq_msg_max;
+ info->attr.mq_msgsize = ipc_ns->mq_msgsize_max;
if (attr) {
info->attr.mq_maxmsg = attr->mq_maxmsg;
info->attr.mq_msgsize = attr->mq_msgsize;
@@ -188,30 +186,38 @@ out_inode:
static int mqueue_fill_super(struct super_block *sb, void *data, int silent)
{
struct inode *inode;
+ struct ipc_namespace *ns = data;
+ int error = 0;
sb->s_blocksize = PAGE_CACHE_SIZE;
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
sb->s_magic = MQUEUE_MAGIC;
sb->s_op = &mqueue_super_ops;
- inode = mqueue_get_inode(sb, S_IFDIR | S_ISVTX | S_IRWXUGO, NULL);
- if (!inode)
- return -ENOMEM;
+ inode = mqueue_get_inode(sb, ns, S_IFDIR | S_ISVTX | S_IRWXUGO,
+ NULL);
+ if (!inode) {
+ error = -ENOMEM;
+ goto out;
+ }
sb->s_root = d_alloc_root(inode);
if (!sb->s_root) {
iput(inode);
- return -ENOMEM;
+ error = -ENOMEM;
}
- return 0;
+out:
+ return error;
}
static int mqueue_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name,
void *data, struct vfsmount *mnt)
{
- return get_sb_single(fs_type, flags, data, mqueue_fill_super, mnt);
+ if (!(flags & MS_KERNMOUNT))
+ data = current->nsproxy->ipc_ns;
+ return get_sb_ns(fs_type, flags, data, mqueue_fill_super, mnt);
}
static void init_once(void *foo)
@@ -242,11 +248,13 @@ static void mqueue_delete_inode(struct inode *inode)
struct user_struct *user;
unsigned long mq_bytes;
int i;
+ struct ipc_namespace *ipc_ns;
if (S_ISDIR(inode->i_mode)) {
clear_inode(inode);
return;
}
+ ipc_ns = get_ns_from_inode(inode);
info = MQUEUE_I(inode);
spin_lock(&info->lock);
for (i = 0; i < info->attr.mq_curmsgs; i++)
@@ -262,10 +270,19 @@ static void mqueue_delete_inode(struct inode *inode)
if (user) {
spin_lock(&mq_lock);
user->mq_bytes -= mq_bytes;
- queues_count--;
+ /*
+ * get_ns_from_inode() ensures that the
+ * (ipc_ns = sb->s_fs_info) is either a valid ipc_ns
+ * to which we now hold a reference, or it is NULL.
+ * We can't put it here under mq_lock, though.
+ */
+ if (ipc_ns)
+ ipc_ns->mq_queues_count--;
spin_unlock(&mq_lock);
free_uid(user);
}
+ if (ipc_ns)
+ put_ipc_ns(ipc_ns);
}
static int mqueue_create(struct inode *dir, struct dentry *dentry,
@@ -274,31 +291,41 @@ static int mqueue_create(struct inode *dir, struct dentry *dentry,
struct inode *inode;
struct mq_attr *attr = dentry->d_fsdata;
int error;
+ struct ipc_namespace *ipc_ns;
spin_lock(&mq_lock);
- if (queues_count >= queues_max && !capable(CAP_SYS_RESOURCE)) {
+ ipc_ns = __get_ns_from_inode(dir);
+ if (!ipc_ns) {
+ error = -EACCES;
+ goto out_unlock;
+ }
+ if (ipc_ns->mq_queues_count >= ipc_ns->mq_queues_max &&
+ !capable(CAP_SYS_RESOURCE)) {
error = -ENOSPC;
- goto out_lock;
+ goto out_unlock;
}
- queues_count++;
+ ipc_ns->mq_queues_count++;
spin_unlock(&mq_lock);
- inode = mqueue_get_inode(dir->i_sb, mode, attr);
+ inode = mqueue_get_inode(dir->i_sb, ipc_ns, mode, attr);
if (!inode) {
error = -ENOMEM;
spin_lock(&mq_lock);
- queues_count--;
- goto out_lock;
+ ipc_ns->mq_queues_count--;
+ goto out_unlock;
}
+ put_ipc_ns(ipc_ns);
dir->i_size += DIRENT_SIZE;
dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME;
d_instantiate(dentry, inode);
dget(dentry);
return 0;
-out_lock:
+out_unlock:
spin_unlock(&mq_lock);
+ if (ipc_ns)
+ put_ipc_ns(ipc_ns);
return error;
}
@@ -562,7 +589,7 @@ static void remove_notification(struct mqueue_inode_info *info)
info->notify_owner = NULL;
}
-static int mq_attr_ok(struct mq_attr *attr)
+static int mq_attr_ok(struct ipc_namespace *ipc_ns, struct mq_attr *attr)
{
if (attr->mq_maxmsg <= 0 || attr->mq_msgsize <= 0)
return 0;
@@ -570,8 +597,8 @@ static int mq_attr_ok(struct mq_attr *attr)
if (attr->mq_maxmsg > HARD_MSGMAX)
return 0;
} else {
- if (attr->mq_maxmsg > msg_max ||
- attr->mq_msgsize > msgsize_max)
+ if (attr->mq_maxmsg > ipc_ns->mq_msg_max ||
+ attr->mq_msgsize > ipc_ns->mq_msgsize_max)
return 0;
}
/* check for overflow */
@@ -587,8 +614,9 @@ static int mq_attr_ok(struct mq_attr *attr)
/*
* Invoked when creating a new queue via sys_mq_open
*/
-static struct file *do_create(struct dentry *dir, struct dentry *dentry,
- int oflag, mode_t mode, struct mq_attr *attr)
+static struct file *do_create(struct ipc_namespace *ipc_ns, struct dentry *dir,
+ struct dentry *dentry, int oflag, mode_t mode,
+ struct mq_attr *attr)
{
const struct cred *cred = current_cred();
struct file *result;
@@ -596,14 +624,14 @@ static struct file *do_create(struct dentry *dir, struct dentry *dentry,
if (attr) {
ret = -EINVAL;
- if (!mq_attr_ok(attr))
+ if (!mq_attr_ok(ipc_ns, attr))
goto out;
/* store for use during create */
dentry->d_fsdata = attr;
}
mode &= ~current_umask();
- ret = mnt_want_write(mqueue_mnt);
+ ret = mnt_want_write(ipc_ns->mq_mnt);
if (ret)
goto out;
ret = vfs_create(dir->d_inode, dentry, mode, NULL);
@@ -611,24 +639,25 @@ static struct file *do_create(struct dentry *dir, struct dentry *dentry,
if (ret)
goto out_drop_write;
- result = dentry_open(dentry, mqueue_mnt, oflag, cred);
+ result = dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred);
/*
* dentry_open() took a persistent mnt_want_write(),
* so we can now drop this one.
*/
- mnt_drop_write(mqueue_mnt);
+ mnt_drop_write(ipc_ns->mq_mnt);
return result;
out_drop_write:
- mnt_drop_write(mqueue_mnt);
+ mnt_drop_write(ipc_ns->mq_mnt);
out:
dput(dentry);
- mntput(mqueue_mnt);
+ mntput(ipc_ns->mq_mnt);
return ERR_PTR(ret);
}
/* Opens existing queue */
-static struct file *do_open(struct dentry *dentry, int oflag)
+static struct file *do_open(struct ipc_namespace *ipc_ns,
+ struct dentry *dentry, int oflag)
{
const struct cred *cred = current_cred();
@@ -637,17 +666,17 @@ static struct file *do_open(struct dentry *dentry, int oflag)
if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY)) {
dput(dentry);
- mntput(mqueue_mnt);
+ mntput(ipc_ns->mq_mnt);
return ERR_PTR(-EINVAL);
}
if (inode_permission(dentry->d_inode, oflag2acc[oflag & O_ACCMODE])) {
dput(dentry);
- mntput(mqueue_mnt);
+ mntput(ipc_ns->mq_mnt);
return ERR_PTR(-EACCES);
}
- return dentry_open(dentry, mqueue_mnt, oflag, cred);
+ return dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred);
}
SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
@@ -658,6 +687,7 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
char *name;
struct mq_attr attr;
int fd, error;
+ struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
if (u_attr && copy_from_user(&attr, u_attr, sizeof(struct mq_attr)))
return -EFAULT;
@@ -671,13 +701,13 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
if (fd < 0)
goto out_putname;
- mutex_lock(&mqueue_mnt->mnt_root->d_inode->i_mutex);
- dentry = lookup_one_len(name, mqueue_mnt->mnt_root, strlen(name));
+ mutex_lock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
+ dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name));
if (IS_ERR(dentry)) {
error = PTR_ERR(dentry);
goto out_err;
}
- mntget(mqueue_mnt);
+ mntget(ipc_ns->mq_mnt);
if (oflag & O_CREAT) {
if (dentry->d_inode) { /* entry already exists */
@@ -685,10 +715,10 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
error = -EEXIST;
if (oflag & O_EXCL)
goto out;
- filp = do_open(dentry, oflag);
+ filp = do_open(ipc_ns, dentry, oflag);
} else {
- filp = do_create(mqueue_mnt->mnt_root, dentry,
- oflag, mode,
+ filp = do_create(ipc_ns, ipc_ns->mq_mnt->mnt_root,
+ dentry, oflag, mode,
u_attr ? &attr : NULL);
}
} else {
@@ -696,7 +726,7 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
if (!dentry->d_inode)
goto out;
audit_inode(name, dentry);
- filp = do_open(dentry, oflag);
+ filp = do_open(ipc_ns, dentry, oflag);
}
if (IS_ERR(filp)) {
@@ -709,13 +739,13 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
out:
dput(dentry);
- mntput(mqueue_mnt);
+ mntput(ipc_ns->mq_mnt);
out_putfd:
put_unused_fd(fd);
out_err:
fd = error;
out_upsem:
- mutex_unlock(&mqueue_mnt->mnt_root->d_inode->i_mutex);
+ mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
out_putname:
putname(name);
return fd;
@@ -727,14 +757,15 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
char *name;
struct dentry *dentry;
struct inode *inode = NULL;
+ struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
name = getname(u_name);
if (IS_ERR(name))
return PTR_ERR(name);
- mutex_lock_nested(&mqueue_mnt->mnt_root->d_inode->i_mutex,
+ mutex_lock_nested(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex,
I_MUTEX_PARENT);
- dentry = lookup_one_len(name, mqueue_mnt->mnt_root, strlen(name));
+ dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name));
if (IS_ERR(dentry)) {
err = PTR_ERR(dentry);
goto out_unlock;
@@ -748,16 +779,16 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
inode = dentry->d_inode;
if (inode)
atomic_inc(&inode->i_count);
- err = mnt_want_write(mqueue_mnt);
+ err = mnt_want_write(ipc_ns->mq_mnt);
if (err)
goto out_err;
err = vfs_unlink(dentry->d_parent->d_inode, dentry);
- mnt_drop_write(mqueue_mnt);
+ mnt_drop_write(ipc_ns->mq_mnt);
out_err:
dput(dentry);
out_unlock:
- mutex_unlock(&mqueue_mnt->mnt_root->d_inode->i_mutex);
+ mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
putname(name);
if (inode)
iput(inode);
@@ -1205,59 +1236,31 @@ static struct file_system_type mqueue_fs_type = {
.kill_sb = kill_litter_super,
};
-static int msg_max_limit_min = MIN_MSGMAX;
-static int msg_max_limit_max = MAX_MSGMAX;
-
-static int msg_maxsize_limit_min = MIN_MSGSIZEMAX;
-static int msg_maxsize_limit_max = MAX_MSGSIZEMAX;
-
-static ctl_table mq_sysctls[] = {
- {
- .procname = "queues_max",
- .data = &queues_max,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = &proc_dointvec,
- },
- {
- .procname = "msg_max",
- .data = &msg_max,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = &proc_dointvec_minmax,
- .extra1 = &msg_max_limit_min,
- .extra2 = &msg_max_limit_max,
- },
- {
- .procname = "msgsize_max",
- .data = &msgsize_max,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = &proc_dointvec_minmax,
- .extra1 = &msg_maxsize_limit_min,
- .extra2 = &msg_maxsize_limit_max,
- },
- { .ctl_name = 0 }
-};
+int mq_init_ns(struct ipc_namespace *ns)
+{
+ ns->mq_queues_count = 0;
+ ns->mq_queues_max = DFLT_QUEUESMAX;
+ ns->mq_msg_max = DFLT_MSGMAX;
+ ns->mq_msgsize_max = DFLT_MSGSIZEMAX;
+
+ ns->mq_mnt = kern_mount_data(&mqueue_fs_type, ns);
+ if (IS_ERR(ns->mq_mnt)) {
+ int err = PTR_ERR(ns->mq_mnt);
+ ns->mq_mnt = NULL;
+ return err;
+ }
+ return 0;
+}
-static ctl_table mq_sysctl_dir[] = {
- {
- .procname = "mqueue",
- .mode = 0555,
- .child = mq_sysctls,
- },
- { .ctl_name = 0 }
-};
+void mq_clear_sbinfo(struct ipc_namespace *ns)
+{
+ ns->mq_mnt->mnt_sb->s_fs_info = NULL;
+}
-static ctl_table mq_sysctl_root[] = {
- {
- .ctl_name = CTL_FS,
- .procname = "fs",
- .mode = 0555,
- .child = mq_sysctl_dir,
- },
- { .ctl_name = 0 }
-};
+void mq_put_mnt(struct ipc_namespace *ns)
+{
+ mntput(ns->mq_mnt);
+}
static int __init init_mqueue_fs(void)
{
@@ -1270,21 +1273,20 @@ static int __init init_mqueue_fs(void)
return -ENOMEM;
/* ignore failues - they are not fatal */
- mq_sysctl_table = register_sysctl_table(mq_sysctl_root);
+ mq_sysctl_table = mq_register_sysctl_table();
error = register_filesystem(&mqueue_fs_type);
if (error)
goto out_sysctl;
- if (IS_ERR(mqueue_mnt = kern_mount(&mqueue_fs_type))) {
- error = PTR_ERR(mqueue_mnt);
+ spin_lock_init(&mq_lock);
+
+ init_ipc_ns.mq_mnt = kern_mount_data(&mqueue_fs_type, &init_ipc_ns);
+ if (IS_ERR(init_ipc_ns.mq_mnt)) {
+ error = PTR_ERR(init_ipc_ns.mq_mnt);
goto out_filesystem;
}
- /* internal initialization - not common for vfs */
- queues_count = 0;
- spin_lock_init(&mq_lock);
-
return 0;
out_filesystem:
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