namespaces: mqueue ns: move mqueue_mnt into struct ipc_namespace (614b84cf) · Commits · 戴 / test

include/linux/ipc_namespace.h

+35 −4

Original line number	Diff line number	Diff line
		@@ -44,24 +44,55 @@ struct ipc_namespace {
		int shm_tot;

		struct notifier_block ipcns_nb;

		/* The kern_mount of the mqueuefs sb. We take a ref on it */
		struct vfsmount *mq_mnt;

		/* # queues in this ns, protected by mq_lock */
		unsigned int mq_queues_count;

		/* next fields are set through sysctl */
		unsigned int mq_queues_max; /* initialized to DFLT_QUEUESMAX */
		unsigned int mq_msg_max; /* initialized to DFLT_MSGMAX */
		unsigned int mq_msgsize_max; /* initialized to DFLT_MSGSIZEMAX */

		};

		extern struct ipc_namespace init_ipc_ns;
		extern atomic_t nr_ipc_ns;

		#ifdef CONFIG_SYSVIPC
		#if defined(CONFIG_POSIX_MQUEUE) \|\| defined(CONFIG_SYSVIPC)
		#define INIT_IPC_NS(ns) .ns = &init_ipc_ns,
		#else
		#define INIT_IPC_NS(ns)
		#endif

		#ifdef CONFIG_SYSVIPC
		extern int register_ipcns_notifier(struct ipc_namespace *);
		extern int cond_register_ipcns_notifier(struct ipc_namespace *);
		extern void unregister_ipcns_notifier(struct ipc_namespace *);
		extern int ipcns_notify(unsigned long);

		#else /* CONFIG_SYSVIPC */
		#define INIT_IPC_NS(ns)
		static inline int register_ipcns_notifier(struct ipc_namespace *ns)
		{ return 0; }
		static inline int cond_register_ipcns_notifier(struct ipc_namespace *ns)
		{ return 0; }
		static inline void unregister_ipcns_notifier(struct ipc_namespace *ns) { }
		static inline int ipcns_notify(unsigned long l) { return 0; }
		#endif /* CONFIG_SYSVIPC */

		#if defined(CONFIG_SYSVIPC) && defined(CONFIG_IPC_NS)
		#ifdef CONFIG_POSIX_MQUEUE
		extern void mq_init_ns(struct ipc_namespace *ns);
		/* 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 */
		#else
		#define mq_init_ns(ns) ((void) 0)
		#endif

		#if defined(CONFIG_IPC_NS)
		extern void free_ipc_ns(struct kref *kref);
		extern struct ipc_namespace *copy_ipcs(unsigned long flags,
		struct ipc_namespace *ns);

init/Kconfig

+2 −2

Original line number	Diff line number	Diff line
		@@ -670,10 +670,10 @@ config UTS_NS

		config IPC_NS
		bool "IPC namespace"
		depends on NAMESPACES && SYSVIPC
		depends on NAMESPACES && (SYSVIPC \|\| POSIX_MQUEUE)
		help
		In this namespace tasks work with IPC ids which correspond to
		different IPC objects in different namespaces
		different IPC objects in different namespaces.

		config USER_NS
		bool "User namespace (EXPERIMENTAL)"

ipc/mqueue.c

+68 −56

Original line number	Diff line number	Diff line
		@@ -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"
		@@ -46,12 +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.
		@@ -95,12 +90,6 @@ 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;

		@@ -109,11 +98,27 @@ static inline struct mqueue_inode_info MQUEUE_I(struct inode inode)
		return container_of(inode, struct mqueue_inode_info, vfs_inode);
		}

		void 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 = mntget(init_ipc_ns.mq_mnt);
		}

		void mq_exit_ns(struct ipc_namespace *ns)
		{
		/* will need to clear out ns->mq_mnt->mnt_sb->s_fs_info here */
		mntput(ns->mq_mnt);
		}

		static struct inode mqueue_get_inode(struct super_block sb, int mode,
		struct mq_attr *attr)
		{
		struct user_struct *u = current_user();
		struct inode *inode;
		struct ipc_namespace *ipc_ns = &init_ipc_ns;

		inode = new_inode(sb);
		if (inode) {
		@@ -141,8 +146,8 @@ 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;
		@@ -242,6 +247,7 @@ static void mqueue_delete_inode(struct inode *inode)
		struct user_struct *user;
		unsigned long mq_bytes;
		int i;
		struct ipc_namespace *ipc_ns = &init_ipc_ns;

		if (S_ISDIR(inode->i_mode)) {
		clear_inode(inode);
		@@ -262,7 +268,7 @@ static void mqueue_delete_inode(struct inode *inode)
		if (user) {
		spin_lock(&mq_lock);
		user->mq_bytes -= mq_bytes;
		queues_count--;
		ipc_ns->mq_queues_count--;
		spin_unlock(&mq_lock);
		free_uid(user);
		}
		@@ -274,21 +280,23 @@ 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 = &init_ipc_ns;

		spin_lock(&mq_lock);
		if (queues_count >= queues_max && !capable(CAP_SYS_RESOURCE)) {
		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);
		if (!inode) {
		error = -ENOMEM;
		spin_lock(&mq_lock);
		queues_count--;
		goto out_lock;
		ipc_ns->mq_queues_count--;
		goto out_unlock;
		}

		dir->i_size += DIRENT_SIZE;
		@@ -297,7 +305,7 @@ static int mqueue_create(struct inode dir, struct dentry dentry,
		d_instantiate(dentry, inode);
		dget(dentry);
		return 0;
		out_lock:
		out_unlock:
		spin_unlock(&mq_lock);
		return error;
		}
		@@ -562,7 +570,7 @@ 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 +578,8 @@ 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 +595,9 @@ 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 +605,14 @@ 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 +620,25 @@ 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 +647,17 @@ 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 +668,7 @@ 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 = &init_ipc_ns;

		if (u_attr && copy_from_user(&attr, u_attr, sizeof(struct mq_attr)))
		return -EFAULT;
		@@ -671,13 +682,13 @@ 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 +696,10 @@ 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 +707,7 @@ 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 +720,13 @@ 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 +738,15 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
		char *name;
		struct dentry *dentry;
		struct inode *inode = NULL;
		struct ipc_namespace *ipc_ns = &init_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 +760,16 @@ 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);
		@@ -1214,14 +1226,14 @@ static int msg_maxsize_limit_max = MAX_MSGSIZEMAX;
		static ctl_table mq_sysctls[] = {
		{
		.procname = "queues_max",
		.data = &queues_max,
		.data = &init_ipc_ns.mq_queues_max,
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = &proc_dointvec,
		},
		{
		.procname = "msg_max",
		.data = &msg_max,
		.data = &init_ipc_ns.mq_msg_max,
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = &proc_dointvec_minmax,
		@@ -1230,7 +1242,7 @@ static ctl_table mq_sysctls[] = {
		},
		{
		.procname = "msgsize_max",
		.data = &msgsize_max,
		.data = &init_ipc_ns.mq_msgsize_max,
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = &proc_dointvec_minmax,
		@@ -1276,13 +1288,13 @@ static int __init init_mqueue_fs(void)
		if (error)
		goto out_sysctl;

		if (IS_ERR(mqueue_mnt = kern_mount(&mqueue_fs_type))) {
		error = PTR_ERR(mqueue_mnt);
		init_ipc_ns.mq_mnt = kern_mount(&mqueue_fs_type);
		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;

ipc/msgutil.c

+22 −0

Original line number	Diff line number	Diff line
		@@ -13,10 +13,32 @@
		#include <linux/security.h>
		#include <linux/slab.h>
		#include <linux/ipc.h>
		#include <linux/ipc_namespace.h>
		#include <asm/uaccess.h>

		#include "util.h"

		/*
		* 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 = {
		.kref = {
		/* It's not for this patch to change, but should this be 1? */
		.refcount = ATOMIC_INIT(2),
		},
		#ifdef CONFIG_POSIX_MQUEUE
		.mq_mnt = NULL,
		.mq_queues_count = 0,
		.mq_queues_max = DFLT_QUEUESMAX,
		.mq_msg_max = DFLT_MSGMAX,
		.mq_msgsize_max = DFLT_MSGSIZEMAX,
		#endif
		};

		atomic_t nr_ipc_ns = ATOMIC_INIT(1);

		struct msg_msgseg {
		struct msg_msgseg* next;
		/* the next part of the message follows immediately */

ipc/namespace.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -25,6 +25,7 @@ static struct ipc_namespace clone_ipc_ns(struct ipc_namespace old_ns)
		sem_init_ns(ns);
		msg_init_ns(ns);
		shm_init_ns(ns);
		mq_init_ns(ns);

		/*
		* msgmni has already been computed for the new ipc ns.
		@@ -101,6 +102,7 @@ void free_ipc_ns(struct kref *kref)
		sem_exit_ns(ns);
		msg_exit_ns(ns);
		shm_exit_ns(ns);
		mq_exit_ns(ns);
		kfree(ns);
		atomic_dec(&nr_ipc_ns);

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