Patch "reiserfs: don't preallocate blocks for extended attributes" has been added to the 4.9-stable tree

Patch "reiserfs: don't preallocate blocks for extended attributes" has been added to the 4.9-stable tree

[gregkh]

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

    reiserfs: don't preallocate blocks for extended attributes

to the 4.9-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:
     reiserfs-don-t-preallocate-blocks-for-extended-attributes.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 54930dfeb46e978b447af0fb8ab4e181c1bf9d7a Mon Sep 17 00:00:00 2001
From: Jeff Mahoney <jeffm@suse.com>
Date: Thu, 22 Jun 2017 16:35:04 -0400
Subject: reiserfs: don't preallocate blocks for extended attributes

From: Jeff Mahoney <jeffm@suse.com>

commit 54930dfeb46e978b447af0fb8ab4e181c1bf9d7a upstream.

Most extended attributes will fit in a single block.  More importantly,
we drop the reference to the inode while holding the transaction open
so the preallocated blocks aren't released.  As a result, the inode
may be evicted before it's removed from the transaction's prealloc list
which can cause memory corruption.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/reiserfs/bitmap.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/reiserfs/bitmap.c
+++ b/fs/reiserfs/bitmap.c
@@ -1136,7 +1136,7 @@ static int determine_prealloc_size(reise
 	hint->prealloc_size = 0;
 
 	if (!hint->formatted_node && hint->preallocate) {
-		if (S_ISREG(hint->inode->i_mode)
+		if (S_ISREG(hint->inode->i_mode) && !IS_PRIVATE(hint->inode)
 		    && hint->inode->i_size >=
 		    REISERFS_SB(hint->th->t_super)->s_alloc_options.
 		    preallocmin * hint->inode->i_sb->s_blocksize)


Patches currently in stable-queue which might be from jeffm@suse.com are

queue-4.9/reiserfs-don-t-preallocate-blocks-for-extended-attributes.patch
queue-4.9/reiserfs-fix-race-in-prealloc-discard.patch