}
/*
- * remove_kevent - cleans up and ultimately frees the given kevent
+ * remove_kevent - cleans up the given kevent
*
* Caller must hold dev->ev_mutex.
*/
dev->event_count--;
dev->queue_size -= sizeof(struct inotify_event) + kevent->event.len;
+}
+/*
+ * free_kevent - frees the given kevent.
+ */
+static void free_kevent(struct inotify_kernel_event *kevent)
+{
kfree(kevent->name);
kmem_cache_free(event_cachep, kevent);
}
struct inotify_kernel_event *kevent;
kevent = inotify_dev_get_event(dev);
remove_kevent(dev, kevent);
+ free_kevent(kevent);
}
}
/*
- * find_inode - resolve a user-given path to a specific inode and return a nd
+ * find_inode - resolve a user-given path to a specific inode
*/
-static int find_inode(const char __user *dirname, struct nameidata *nd,
+static int find_inode(const char __user *dirname, struct path *path,
unsigned flags)
{
int error;
- error = __user_walk(dirname, flags, nd);
+ error = user_path_at(AT_FDCWD, dirname, flags, path);
if (error)
return error;
/* you can only watch an inode if you have read permissions on it */
- error = vfs_permission(nd, MAY_READ);
+ error = inode_permission(path->dentry->d_inode, MAY_READ);
if (error)
- path_put(&nd->path);
+ path_put(path);
return error;
}
dev = file->private_data;
while (1) {
- int events;
prepare_to_wait(&dev->wq, &wait, TASK_INTERRUPTIBLE);
mutex_lock(&dev->ev_mutex);
- events = !list_empty(&dev->events);
- mutex_unlock(&dev->ev_mutex);
- if (events) {
+ if (!list_empty(&dev->events)) {
ret = 0;
break;
}
+ mutex_unlock(&dev->ev_mutex);
if (file->f_flags & O_NONBLOCK) {
ret = -EAGAIN;
if (ret)
return ret;
- mutex_lock(&dev->ev_mutex);
while (1) {
struct inotify_kernel_event *kevent;
}
break;
}
+ remove_kevent(dev, kevent);
+
+ /*
+ * Must perform the copy_to_user outside the mutex in order
+ * to avoid a lock order reversal with mmap_sem.
+ */
+ mutex_unlock(&dev->ev_mutex);
if (copy_to_user(buf, &kevent->event, event_size)) {
ret = -EFAULT;
count -= kevent->event.len;
}
- remove_kevent(dev, kevent);
+ free_kevent(kevent);
+
+ mutex_lock(&dev->ev_mutex);
}
mutex_unlock(&dev->ev_mutex);
.destroy_watch = free_inotify_user_watch,
};
-asmlinkage long sys_inotify_init(void)
+asmlinkage long sys_inotify_init1(int flags)
{
struct inotify_device *dev;
struct inotify_handle *ih;
struct file *filp;
int fd, ret;
- fd = get_unused_fd();
+ /* Check the IN_* constants for consistency. */
+ BUILD_BUG_ON(IN_CLOEXEC != O_CLOEXEC);
+ BUILD_BUG_ON(IN_NONBLOCK != O_NONBLOCK);
+
+ if (flags & ~(IN_CLOEXEC | IN_NONBLOCK))
+ return -EINVAL;
+
+ fd = get_unused_fd_flags(flags & O_CLOEXEC);
if (fd < 0)
return fd;
filp->f_path.dentry = dget(inotify_mnt->mnt_root);
filp->f_mapping = filp->f_path.dentry->d_inode->i_mapping;
filp->f_mode = FMODE_READ;
- filp->f_flags = O_RDONLY;
+ filp->f_flags = O_RDONLY | (flags & O_NONBLOCK);
filp->private_data = dev;
INIT_LIST_HEAD(&dev->events);
return ret;
}
-asmlinkage long sys_inotify_add_watch(int fd, const char __user *path, u32 mask)
+asmlinkage long sys_inotify_init(void)
+{
+ return sys_inotify_init1(0);
+}
+
+asmlinkage long sys_inotify_add_watch(int fd, const char __user *pathname, u32 mask)
{
struct inode *inode;
struct inotify_device *dev;
- struct nameidata nd;
+ struct path path;
struct file *filp;
int ret, fput_needed;
unsigned flags = 0;
if (mask & IN_ONLYDIR)
flags |= LOOKUP_DIRECTORY;
- ret = find_inode(path, &nd, flags);
+ ret = find_inode(pathname, &path, flags);
if (unlikely(ret))
goto fput_and_out;
- /* inode held in place by reference to nd; dev by fget on fd */
- inode = nd.path.dentry->d_inode;
+ /* inode held in place by reference to path; dev by fget on fd */
+ inode = path.dentry->d_inode;
dev = filp->private_data;
mutex_lock(&dev->up_mutex);
ret = create_watch(dev, inode, mask);
mutex_unlock(&dev->up_mutex);
- path_put(&nd.path);
+ path_put(&path);
fput_and_out:
fput_light(filp, fput_needed);
return ret;