[PATCH 1/2] ocfs2: Fix data corruption on truncate

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



ocfs2_truncate_file() did unmap invalidate page cache pages before
zeroing partial tail cluster and setting i_size. Thus some pages could
be left (and likely have left if the cluster zeroing happened) in the
page cache beyond i_size after truncate finished letting user possibly
see stale data once the file was extended again. Also the tail cluster
zeroing was not guaranteed to finish before truncate finished causing
possible stale data exposure. The problem started to be particularly
easy to hit after commit 6dbf7bb55598 "fs: Don't invalidate page buffers
in block_write_full_page()" stopped invalidation of pages beyond i_size
from page writeback path.

Fix these problems by unmapping and invalidating pages in the page cache
after the i_size is reduced and tail cluster is zeroed out.

CC: stable@xxxxxxxxxxxxxxx
Fixes: ccd979bdbce9 ("[PATCH] OCFS2: The Second Oracle Cluster Filesystem")
Signed-off-by: Jan Kara <jack@xxxxxxx>
---
 fs/ocfs2/file.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 54d7843c0211..fc5f780fa235 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -476,10 +476,11 @@ int ocfs2_truncate_file(struct inode *inode,
 	 * greater than page size, so we have to truncate them
 	 * anyway.
 	 */
-	unmap_mapping_range(inode->i_mapping, new_i_size + PAGE_SIZE - 1, 0, 1);
-	truncate_inode_pages(inode->i_mapping, new_i_size);
 
 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+		unmap_mapping_range(inode->i_mapping,
+				    new_i_size + PAGE_SIZE - 1, 0, 1);
+		truncate_inode_pages(inode->i_mapping, new_i_size);
 		status = ocfs2_truncate_inline(inode, di_bh, new_i_size,
 					       i_size_read(inode), 1);
 		if (status)
@@ -498,6 +499,9 @@ int ocfs2_truncate_file(struct inode *inode,
 		goto bail_unlock_sem;
 	}
 
+	unmap_mapping_range(inode->i_mapping, new_i_size + PAGE_SIZE - 1, 0, 1);
+	truncate_inode_pages(inode->i_mapping, new_i_size);
+
 	status = ocfs2_commit_truncate(osb, inode, di_bh);
 	if (status < 0) {
 		mlog_errno(status);
-- 
2.26.2




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux