The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 82a25b027ca48d7ef197295846b352345853dfa8 Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@xxxxxxx>
Date: Thu, 23 May 2019 23:07:08 -0400
Subject: [PATCH] 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@xxxxxxxxxxxxxxx
Fixes: 1c9114f9c0f1 ("ext4: serialize unlocked dio reads with truncate")
Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx>
Signed-off-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 82298c63ea6d..9bcb7f2b86dd 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -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);
-
- /*
- * Blocks are going to be removed from the inode. Wait
- * for dio in flight. Temporarily disable
- * dioread_nolock to prevent livelock.
- */
- if (orphan) {
- if (!ext4_should_journal_data(inode)) {
- inode_dio_wait(inode);
- } else
- ext4_wait_for_tail_page_commit(inode);
+ } else {
+ /*
+ * Blocks are going to be removed from the inode. Wait
+ * for dio in flight.
+ */
+ inode_dio_wait(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);
