[01/80] eCryptfs: Flush file in vma close

Greg KH
2011-12-07T16:16:51Z

From: Tyler Hicks <tyhicks@canonical.com>

commit 32001d6fe9ac6b0423e674a3093aa56740849f3b upstream.

Dirty pages weren't being written back when an mmap'ed eCryptfs file was
closed before the mapping was unmapped. Since f_ops->flush() is not
called by the munmap() path, the lower file was simply being released.
This patch flushes the eCryptfs file in the vm_ops->close() path.

https://launchpad.net/bugs/870326

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
fs/ecryptfs/file.c | 23 ++++++++++++++++++++++-
1 file changed, 22 insertions(+), 1 deletion(-)

--- a/fs/ecryptfs/file.c
+++ b/fs/ecryptfs/file.c
@@ -139,6 +139,27 @@ out:
return rc;
}

+static void ecryptfs_vma_close(struct vm_area_struct *vma)
+{
+ filemap_write_and_wait(vma->vm_file->f_mapping);
+}
+
+static const struct vm_operations_struct ecryptfs_file_vm_ops = {
+ .close = ecryptfs_vma_close,
+ .fault = filemap_fault,
+};
+
+static int ecryptfs_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ int rc;
+
+ rc = generic_file_mmap(file, vma);
+ if (!rc)
+ vma->vm_ops = &ecryptfs_file_vm_ops;
+
+ return rc;
+}
+
struct kmem_cache *ecryptfs_file_info_cache;

/**
@@ -348,7 +369,7 @@ const struct file_operations ecryptfs_ma
#ifdef CONFIG_COMPAT
.compat_ioctl = ecryptfs_compat_ioctl,
#endif
- .mmap = generic_file_mmap,
+ .mmap = ecryptfs_file_mmap,
.open = ecryptfs_open,
.flush = ecryptfs_flush,
.release = ecryptfs_release,