Commit 82a25b02 authored May 23, 2019 by Jan Kara Committed by Theodore Ts'o May 23, 2019

ext4: wait for outstanding dio during truncate in nojournal mode



We didn't wait for outstanding direct IO during truncate in nojournal
mode (as we skip orphan handling in that case). This can lead to fs
corruption or stale data exposure if truncate ends up freeing blocks
and these get reallocated before direct IO finishes. Fix the condition
determining whether the wait is necessary.

CC: stable@vger.kernel.org
Fixes: 1c9114f9 ("ext4: serialize unlocked dio reads with truncate")
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

parent 0a944e8a

fs/ext4/inode.c

+9 −12

Original line number	Diff line number	Diff line
		@@ -5630,20 +5630,17 @@ int ext4_setattr(struct dentry dentry, struct iattr attr)
		goto err_out;
		}
		}
		if (!shrink)
		if (!shrink) {
		pagecache_isize_extended(inode, oldsize, inode->i_size);

		} else {
		/*
		* Blocks are going to be removed from the inode. Wait
		* for dio in flight. Temporarily disable
		* dioread_nolock to prevent livelock.
		* for dio in flight.
		*/
		if (orphan) {
		if (!ext4_should_journal_data(inode)) {
		inode_dio_wait(inode);
		} else
		ext4_wait_for_tail_page_commit(inode);
		}
		if (orphan && ext4_should_journal_data(inode))
		ext4_wait_for_tail_page_commit(inode);
		down_write(&EXT4_I(inode)->i_mmap_sem);

		rc = ext4_break_layouts(inode);