Merge tag 'vfs-6.13.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull netfs updates from Christian Brauner:
 "Various fixes for the netfs library and related infrastructure:

  cachefiles:

   - Fix a dentry leak in cachefiles_open_file()

   - Fix incorrect length return value in
     cachefiles_ondemand_fd_write_iter()

   - Fix missing pos updates in cachefiles_ondemand_fd_write_iter()

   - Clean up in cachefiles_commit_tmpfile()

   - Fix NULL pointer dereference in object->file

   - Add a memory barrier for FSCACHE_VOLUME_CREATING

  netfs:

   - Remove call to folio_index()

   - Fix a few minor bugs in netfs_page_mkwrite()

   - Remove unnecessary references to pages"

* tag 'vfs-6.13.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  netfs/fscache: Add a memory barrier for FSCACHE_VOLUME_CREATING
  cachefiles: Fix NULL pointer dereference in object->file
  cachefiles: Clean up in cachefiles_commit_tmpfile()
  cachefiles: Fix missing pos updates in cachefiles_ondemand_fd_write_iter()
  cachefiles: Fix incorrect length return value in cachefiles_ondemand_fd_write_iter()
  netfs: Remove unnecessary references to pages
  netfs: Fix a few minor bugs in netfs_page_mkwrite()
  netfs: Remove call to folio_index()

1 files changed, 29 insertions, 9 deletions

diff --git a/fs/cachefiles/ondemand.c b/fs/cachefiles/ondemand.c
index 470c96658385..fe3de9ad57bf 100644
--- a/fs/cachefiles/ondemand.c
+++ b/fs/cachefiles/ondemand.c
@@ -60,26 +60,36 @@ static ssize_t cachefiles_ondemand_fd_write_iter(struct kiocb *kiocb,
 {
 	struct cachefiles_object *object = kiocb->ki_filp->private_data;
 	struct cachefiles_cache *cache = object->volume->cache;
-	struct file *file = object->file;
-	size_t len = iter->count;
+	struct file *file;
+	size_t len = iter->count, aligned_len = len;
 	loff_t pos = kiocb->ki_pos;
 	const struct cred *saved_cred;
 	int ret;
 
-	if (!file)
+	spin_lock(&object->lock);
+	file = object->file;
+	if (!file) {
+		spin_unlock(&object->lock);
 		return -ENOBUFS;
+	}
+	get_file(file);
+	spin_unlock(&object->lock);
 
 	cachefiles_begin_secure(cache, &saved_cred);
-	ret = __cachefiles_prepare_write(object, file, &pos, &len, len, true);
+	ret = __cachefiles_prepare_write(object, file, &pos, &aligned_len, len, true);
 	cachefiles_end_secure(cache, saved_cred);
 	if (ret < 0)
-		return ret;
+		goto out;
 
 	trace_cachefiles_ondemand_fd_write(object, file_inode(file), pos, len);
 	ret = __cachefiles_write(object, file, pos, iter, NULL, NULL);
-	if (!ret)
+	if (!ret) {
 		ret = len;
+		kiocb->ki_pos += ret;
+	}
 
+out:
+	fput(file);
 	return ret;
 }
 
@@ -87,12 +97,22 @@ static loff_t cachefiles_ondemand_fd_llseek(struct file *filp, loff_t pos,
 					    int whence)
 {
 	struct cachefiles_object *object = filp->private_data;
-	struct file *file = object->file;
+	struct file *file;
+	loff_t ret;
 
-	if (!file)
+	spin_lock(&object->lock);
+	file = object->file;
+	if (!file) {
+		spin_unlock(&object->lock);
 		return -ENOBUFS;
+	}
+	get_file(file);
+	spin_unlock(&object->lock);
 
-	return vfs_llseek(file, pos, whence);
+	ret = vfs_llseek(file, pos, whence);
+	fput(file);
+
+	return ret;
 }
 
 static long cachefiles_ondemand_fd_ioctl(struct file *filp, unsigned int ioctl,