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[PATCH] eCryptfs: convert f_op->write() to vfs_write()

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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>
This commit is contained in:
Michael Halcrow
2007-02-12 00:53:48 -08:00
committed by Linus Torvalds
parent e77a56ddce
commit 70456600f4
2 changed files with 23 additions and 6 deletions
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27
fs/ecryptfs/crypto.c
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@ -1344,24 +1344,41 @@ static int ecryptfs_write_metadata_to_contents(struct ecryptfs_crypt_stat *crypt
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,