[PATCH] eCryptfs: convert f_op->write() to vfs_write()
sys_write() takes a local copy of f_pos and writes that back
into the struct file. It does this so that two concurrent write()
callers don't make a mess of f_pos, and of the file contents.
ecryptfs should be calling vfs_write(). That way we also get the fsnotify
notifications, which ecryptfs presently appears to have subverted.
Convert direct calls to f_op->write() into calls to vfs_write().
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index 44c2ec2..2d7db61 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -1344,24 +1344,41 @@
mm_segment_t oldfs;
int current_header_page;
int header_pages;
+ ssize_t size;
+ int rc = 0;
lower_file->f_pos = 0;
oldfs = get_fs();
set_fs(get_ds());
- lower_file->f_op->write(lower_file, (char __user *)page_virt,
- PAGE_CACHE_SIZE, &lower_file->f_pos);
+ size = vfs_write(lower_file, (char __user *)page_virt, PAGE_CACHE_SIZE,
+ &lower_file->f_pos);
+ if (size < 0) {
+ rc = (int)size;
+ printk(KERN_ERR "Error attempting to write lower page; "
+ "rc = [%d]\n", rc);
+ set_fs(oldfs);
+ goto out;
+ }
header_pages = ((crypt_stat->header_extent_size
* crypt_stat->num_header_extents_at_front)
/ PAGE_CACHE_SIZE);
memset(page_virt, 0, PAGE_CACHE_SIZE);
current_header_page = 1;
while (current_header_page < header_pages) {
- lower_file->f_op->write(lower_file, (char __user *)page_virt,
- PAGE_CACHE_SIZE, &lower_file->f_pos);
+ size = vfs_write(lower_file, (char __user *)page_virt,
+ PAGE_CACHE_SIZE, &lower_file->f_pos);
+ if (size < 0) {
+ rc = (int)size;
+ printk(KERN_ERR "Error attempting to write lower page; "
+ "rc = [%d]\n", rc);
+ set_fs(oldfs);
+ goto out;
+ }
current_header_page++;
}
set_fs(oldfs);
- return 0;
+out:
+ return rc;
}
static int ecryptfs_write_metadata_to_xattr(struct dentry *ecryptfs_dentry,