diff options
Diffstat (limited to 'ipc/mqueue.c')
-rw-r--r-- | ipc/mqueue.c | 118 |
1 files changed, 66 insertions, 52 deletions
diff --git a/ipc/mqueue.c b/ipc/mqueue.c index beff0cfcd1e8..5eea4dc0509e 100644 --- a/ipc/mqueue.c +++ b/ipc/mqueue.c @@ -45,6 +45,7 @@ struct mqueue_fs_context { struct ipc_namespace *ipc_ns; + bool newns; /* Set if newly created ipc namespace */ }; #define MQUEUE_MAGIC 0x19800202 @@ -144,7 +145,7 @@ struct mqueue_inode_info { struct pid *notify_owner; u32 notify_self_exec_id; struct user_namespace *notify_user_ns; - struct user_struct *user; /* user who created, for accounting */ + struct ucounts *ucounts; /* user who created, for accounting */ struct sock *notify_sock; struct sk_buff *notify_cookie; @@ -163,8 +164,6 @@ static void remove_notification(struct mqueue_inode_info *info); static struct kmem_cache *mqueue_inode_cachep; -static struct ctl_table_header *mq_sysctl_table; - static inline struct mqueue_inode_info *MQUEUE_I(struct inode *inode) { return container_of(inode, struct mqueue_inode_info, vfs_inode); @@ -292,7 +291,6 @@ static struct inode *mqueue_get_inode(struct super_block *sb, struct ipc_namespace *ipc_ns, umode_t mode, struct mq_attr *attr) { - struct user_struct *u = current_user(); struct inode *inode; int ret = -ENOMEM; @@ -304,7 +302,7 @@ static struct inode *mqueue_get_inode(struct super_block *sb, inode->i_mode = mode; inode->i_uid = current_fsuid(); inode->i_gid = current_fsgid(); - inode->i_mtime = inode->i_ctime = inode->i_atime = current_time(inode); + simple_inode_init_ts(inode); if (S_ISREG(mode)) { struct mqueue_inode_info *info; @@ -321,7 +319,7 @@ static struct inode *mqueue_get_inode(struct super_block *sb, info->notify_owner = NULL; info->notify_user_ns = NULL; info->qsize = 0; - info->user = NULL; /* set when all is ok */ + info->ucounts = NULL; /* set when all is ok */ info->msg_tree = RB_ROOT; info->msg_tree_rightmost = NULL; info->node_cache = NULL; @@ -371,19 +369,23 @@ static struct inode *mqueue_get_inode(struct super_block *sb, if (mq_bytes + mq_treesize < mq_bytes) goto out_inode; mq_bytes += mq_treesize; - spin_lock(&mq_lock); - if (u->mq_bytes + mq_bytes < u->mq_bytes || - u->mq_bytes + mq_bytes > rlimit(RLIMIT_MSGQUEUE)) { + info->ucounts = get_ucounts(current_ucounts()); + if (info->ucounts) { + long msgqueue; + + spin_lock(&mq_lock); + msgqueue = inc_rlimit_ucounts(info->ucounts, UCOUNT_RLIMIT_MSGQUEUE, mq_bytes); + if (msgqueue == LONG_MAX || msgqueue > rlimit(RLIMIT_MSGQUEUE)) { + dec_rlimit_ucounts(info->ucounts, UCOUNT_RLIMIT_MSGQUEUE, mq_bytes); + spin_unlock(&mq_lock); + put_ucounts(info->ucounts); + info->ucounts = NULL; + /* mqueue_evict_inode() releases info->messages */ + ret = -EMFILE; + goto out_inode; + } spin_unlock(&mq_lock); - /* mqueue_evict_inode() releases info->messages */ - ret = -EMFILE; - goto out_inode; } - u->mq_bytes += mq_bytes; - spin_unlock(&mq_lock); - - /* all is ok */ - info->user = get_uid(u); } else if (S_ISDIR(mode)) { inc_nlink(inode); /* Some things misbehave if size == 0 on a directory */ @@ -424,6 +426,14 @@ static int mqueue_get_tree(struct fs_context *fc) { struct mqueue_fs_context *ctx = fc->fs_private; + /* + * With a newly created ipc namespace, we don't need to do a search + * for an ipc namespace match, but we still need to set s_fs_info. + */ + if (ctx->newns) { + fc->s_fs_info = ctx->ipc_ns; + return get_tree_nodev(fc, mqueue_fill_super); + } return get_tree_keyed(fc, mqueue_fill_super, ctx->ipc_ns); } @@ -451,6 +461,10 @@ static int mqueue_init_fs_context(struct fs_context *fc) return 0; } +/* + * mq_init_ns() is currently the only caller of mq_create_mount(). + * So the ns parameter is always a newly created ipc namespace. + */ static struct vfsmount *mq_create_mount(struct ipc_namespace *ns) { struct mqueue_fs_context *ctx; @@ -462,6 +476,7 @@ static struct vfsmount *mq_create_mount(struct ipc_namespace *ns) return ERR_CAST(fc); ctx = fc->fs_private; + ctx->newns = true; put_ipc_ns(ctx->ipc_ns); ctx->ipc_ns = get_ipc_ns(ns); put_user_ns(fc->user_ns); @@ -474,7 +489,7 @@ static struct vfsmount *mq_create_mount(struct ipc_namespace *ns) static void init_once(void *foo) { - struct mqueue_inode_info *p = (struct mqueue_inode_info *) foo; + struct mqueue_inode_info *p = foo; inode_init_once(&p->vfs_inode); } @@ -483,7 +498,7 @@ static struct inode *mqueue_alloc_inode(struct super_block *sb) { struct mqueue_inode_info *ei; - ei = kmem_cache_alloc(mqueue_inode_cachep, GFP_KERNEL); + ei = alloc_inode_sb(sb, mqueue_inode_cachep, GFP_KERNEL); if (!ei) return NULL; return &ei->vfs_inode; @@ -497,7 +512,6 @@ static void mqueue_free_inode(struct inode *inode) static void mqueue_evict_inode(struct inode *inode) { struct mqueue_inode_info *info; - struct user_struct *user; struct ipc_namespace *ipc_ns; struct msg_msg *msg, *nmsg; LIST_HEAD(tmp_msg); @@ -520,8 +534,7 @@ static void mqueue_evict_inode(struct inode *inode) free_msg(msg); } - user = info->user; - if (user) { + if (info->ucounts) { unsigned long mq_bytes, mq_treesize; /* Total amount of bytes accounted for the mqueue */ @@ -533,7 +546,7 @@ static void mqueue_evict_inode(struct inode *inode) info->attr.mq_msgsize); spin_lock(&mq_lock); - user->mq_bytes -= mq_bytes; + dec_rlimit_ucounts(info->ucounts, UCOUNT_RLIMIT_MSGQUEUE, mq_bytes); /* * get_ns_from_inode() ensures that the * (ipc_ns = sb->s_fs_info) is either a valid ipc_ns @@ -543,7 +556,8 @@ static void mqueue_evict_inode(struct inode *inode) if (ipc_ns) ipc_ns->mq_queues_count--; spin_unlock(&mq_lock); - free_uid(user); + put_ucounts(info->ucounts); + info->ucounts = NULL; } if (ipc_ns) put_ipc_ns(ipc_ns); @@ -582,7 +596,7 @@ static int mqueue_create_attr(struct dentry *dentry, umode_t mode, void *arg) put_ipc_ns(ipc_ns); dir->i_size += DIRENT_SIZE; - dir->i_ctime = dir->i_mtime = dir->i_atime = current_time(dir); + simple_inode_init_ts(dir); d_instantiate(dentry, inode); dget(dentry); @@ -594,8 +608,8 @@ out_unlock: return error; } -static int mqueue_create(struct inode *dir, struct dentry *dentry, - umode_t mode, bool excl) +static int mqueue_create(struct mnt_idmap *idmap, struct inode *dir, + struct dentry *dentry, umode_t mode, bool excl) { return mqueue_create_attr(dentry, mode, NULL); } @@ -604,7 +618,7 @@ static int mqueue_unlink(struct inode *dir, struct dentry *dentry) { struct inode *inode = d_inode(dentry); - dir->i_ctime = dir->i_mtime = dir->i_atime = current_time(dir); + simple_inode_init_ts(dir); dir->i_size -= DIRENT_SIZE; drop_nlink(inode); dput(dentry); @@ -621,7 +635,8 @@ static int mqueue_unlink(struct inode *dir, struct dentry *dentry) static ssize_t mqueue_read_file(struct file *filp, char __user *u_data, size_t count, loff_t *off) { - struct mqueue_inode_info *info = MQUEUE_I(file_inode(filp)); + struct inode *inode = file_inode(filp); + struct mqueue_inode_info *info = MQUEUE_I(inode); char buffer[FILENT_SIZE]; ssize_t ret; @@ -642,7 +657,7 @@ static ssize_t mqueue_read_file(struct file *filp, char __user *u_data, if (ret <= 0) return ret; - file_inode(filp)->i_atime = file_inode(filp)->i_ctime = current_time(file_inode(filp)); + inode_set_atime_to_ts(inode, inode_set_ctime_current(inode)); return ret; } @@ -873,7 +888,7 @@ static int prepare_open(struct dentry *dentry, int oflag, int ro, if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY)) return -EINVAL; acc = oflag2acc[oflag & O_ACCMODE]; - return inode_permission(d_inode(dentry), acc); + return inode_permission(&nop_mnt_idmap, d_inode(dentry), acc); } static int do_mq_open(const char __user *u_name, int oflag, umode_t mode, @@ -965,14 +980,14 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name) err = -ENOENT; } else { ihold(inode); - err = vfs_unlink(d_inode(dentry->d_parent), dentry, NULL); + err = vfs_unlink(&nop_mnt_idmap, d_inode(dentry->d_parent), + dentry, NULL); } dput(dentry); out_unlock: inode_unlock(d_inode(mnt->mnt_root)); - if (inode) - iput(inode); + iput(inode); mnt_drop_write(mnt); out_name: putname(name); @@ -1003,12 +1018,14 @@ static inline void __pipelined_op(struct wake_q_head *wake_q, struct mqueue_inode_info *info, struct ext_wait_queue *this) { + struct task_struct *task; + list_del(&this->list); - get_task_struct(this->task); + task = get_task_struct(this->task); /* see MQ_BARRIER for purpose/pairing */ smp_store_release(&this->state, STATE_READY); - wake_q_add_safe(wake_q, this->task); + wake_q_add_safe(wake_q, task); } /* pipelined_send() - send a message directly to the task waiting in @@ -1146,8 +1163,7 @@ static int do_mq_timedsend(mqd_t mqdes, const char __user *u_msg_ptr, goto out_unlock; __do_notify(info); } - inode->i_atime = inode->i_mtime = inode->i_ctime = - current_time(inode); + simple_inode_init_ts(inode); } out_unlock: spin_unlock(&info->lock); @@ -1241,8 +1257,7 @@ static int do_mq_timedreceive(mqd_t mqdes, char __user *u_msg_ptr, msg_ptr = msg_get(info); - inode->i_atime = inode->i_mtime = inode->i_ctime = - current_time(inode); + simple_inode_init_ts(inode); /* There is now free space in queue. */ pipelined_receive(&wake_q, info); @@ -1380,7 +1395,8 @@ retry: if (notification == NULL) { if (info->notify_owner == task_tgid(current)) { remove_notification(info); - inode->i_atime = inode->i_ctime = current_time(inode); + inode_set_atime_to_ts(inode, + inode_set_ctime_current(inode)); } } else if (info->notify_owner != NULL) { ret = -EBUSY; @@ -1406,7 +1422,7 @@ retry: info->notify_owner = get_pid(task_tgid(current)); info->notify_user_ns = get_user_ns(current_user_ns()); - inode->i_atime = inode->i_ctime = current_time(inode); + inode_set_atime_to_ts(inode, inode_set_ctime_current(inode)); } spin_unlock(&info->lock); out_fput: @@ -1469,7 +1485,7 @@ static int do_mq_getsetattr(int mqdes, struct mq_attr *new, struct mq_attr *old) f.file->f_flags &= ~O_NONBLOCK; spin_unlock(&f.file->f_lock); - inode->i_atime = inode->i_ctime = current_time(inode); + inode_set_atime_to_ts(inode, inode_set_ctime_current(inode)); } spin_unlock(&info->lock); @@ -1693,11 +1709,6 @@ void mq_clear_sbinfo(struct ipc_namespace *ns) ns->mq_mnt->mnt_sb->s_fs_info = NULL; } -void mq_put_mnt(struct ipc_namespace *ns) -{ - kern_unmount(ns->mq_mnt); -} - static int __init init_mqueue_fs(void) { int error; @@ -1708,8 +1719,11 @@ static int __init init_mqueue_fs(void) if (mqueue_inode_cachep == NULL) return -ENOMEM; - /* ignore failures - they are not fatal */ - mq_sysctl_table = mq_register_sysctl_table(); + if (!setup_mq_sysctls(&init_ipc_ns)) { + pr_warn("sysctl registration failed\n"); + error = -ENOMEM; + goto out_kmem; + } error = register_filesystem(&mqueue_fs_type); if (error) @@ -1726,8 +1740,8 @@ static int __init init_mqueue_fs(void) out_filesystem: unregister_filesystem(&mqueue_fs_type); out_sysctl: - if (mq_sysctl_table) - unregister_sysctl_table(mq_sysctl_table); + retire_mq_sysctls(&init_ipc_ns); +out_kmem: kmem_cache_destroy(mqueue_inode_cachep); return error; } |