Patch "ext4: don't call ext4_should_journal_data() on the journal inode" has been added to the 3.14-stable tree

This is a note to let you know that I've just added the patch titled

ext4: don't call ext4_should_journal_data() on the journal inode

to the 3.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
ext4-don-t-call-ext4_should_journal_data-on-the-journal-inode.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Vegard Nossum <[email protected]>
Date: Mon, 4 Jul 2016 11:03:00 -0400
Subject: ext4: don't call ext4_should_journal_data() on the journal inode

From: Vegard Nossum <[email protected]>

commit 6a7fd522a7c94cdef0a3b08acf8e6702056e635c upstream.

If ext4_fill_super() fails early, it's possible for ext4_evict_inode() to call ext4_should_journal_data() before superblock options and flags are fully set up. In that case, the iput() on the journal inode can end up causing a BUG().

Work around this problem by reordering the tests so we only call ext4_should_journal_data() after we know it's not the journal inode.

---
 fs/ext4/inode.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

@@ -204,9 +204,9 @@ void ext4_evict_inode(struct inode *inod
 		 * Note that directories do not have this problem because they
 		 * don't use page cache.
 		 */
-		if (ext4_should_journal_data(inode) &&
-		    (S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode)) &&
-		    inode->i_ino != EXT4_JOURNAL_INO) {
+		if (inode->i_ino != EXT4_JOURNAL_INO &&
+		    ext4_should_journal_data(inode) &&
+		    (S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode))) {
 			journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
 			tid_t commit_tid = EXT4_I(inode)->i_datasync_tid;
 

Patches currently in stable-queue which might be from [email protected] are

queue-3.14/ext4-short-cut-orphan-cleanup-on-error.patch queue-3.14/block-fix-use-after-free-in-seq-file.patch queue-3.14/ext4-check-for-extents-that-wrap-around.patch queue-3.14/ext4-don-t-call-ext4_should_journal_data-on-the-journal-inode.patch