Patch "crush: fix a bug in tree bucket decode" has been added to the 4.1-stable tree

Patch "crush: fix a bug in tree bucket decode" has been added to the 4.1-stable tree

[gregkh]

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

    crush: fix a bug in tree bucket decode

to the 4.1-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:
     crush-fix-a-bug-in-tree-bucket-decode.patch
and it can be found in the queue-4.1 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 82cd003a77173c91b9acad8033fb7931dac8d751 Mon Sep 17 00:00:00 2001
From: Ilya Dryomov <idryomov@gmail.com>
Date: Mon, 29 Jun 2015 19:30:23 +0300
Subject: crush: fix a bug in tree bucket decode

From: Ilya Dryomov <idryomov@gmail.com>

commit 82cd003a77173c91b9acad8033fb7931dac8d751 upstream.

struct crush_bucket_tree::num_nodes is u8, so ceph_decode_8_safe()
should be used.  -Wconversion catches this, but I guess it went
unnoticed in all the noise it spews.  The actual problem (at least for
common crushmaps) isn't the u32 -> u8 truncation though - it's the
advancement by 4 bytes instead of 1 in the crushmap buffer.

Fixes: http://tracker.ceph.com/issues/2759

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Josh Durgin <jdurgin@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/ceph/osdmap.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/ceph/osdmap.c
+++ b/net/ceph/osdmap.c
@@ -89,7 +89,7 @@ static int crush_decode_tree_bucket(void
 {
 	int j;
 	dout("crush_decode_tree_bucket %p to %p\n", *p, end);
-	ceph_decode_32_safe(p, end, b->num_nodes, bad);
+	ceph_decode_8_safe(p, end, b->num_nodes, bad);
 	b->node_weights = kcalloc(b->num_nodes, sizeof(u32), GFP_NOFS);
 	if (b->node_weights == NULL)
 		return -ENOMEM;


Patches currently in stable-queue which might be from idryomov@gmail.com are

queue-4.1/crush-fix-a-bug-in-tree-bucket-decode.patch