diff options
Diffstat (limited to 'ipc/mqueue.c')
-rw-r--r-- | ipc/mqueue.c | 124 |
1 files changed, 68 insertions, 56 deletions
diff --git a/ipc/mqueue.c b/ipc/mqueue.c index 916785363f0..a3673a09069 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" @@ -46,12 +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; |