From: Li Zefan <lizf@cn.fujitsu.com>
Date: Tue, 6 Sep 2011 08:55:34 +0000 (+0800)
Subject: Btrfs: fix array bound checking
X-Git-Tag: v2.6.39-400.9.0~845^2~47
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=3ad8efdb47830b4c2937921f8a22f89555591f4a;p=users%2Fjedix%2Flinux-maple.git

Btrfs: fix array bound checking

Otherwise we can execced the array bound of path->slots[].

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
(cherry picked from commit a05a9bb18ae0abec0b513b5fde876c47905fa13e)
---

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 011cab3aca8d..0fe615e4ea38 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -902,9 +902,10 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
 
 	orig_ptr = btrfs_node_blockptr(mid, orig_slot);
 
-	if (level < BTRFS_MAX_LEVEL - 1)
+	if (level < BTRFS_MAX_LEVEL - 1) {
 		parent = path->nodes[level + 1];
-	pslot = path->slots[level + 1];
+		pslot = path->slots[level + 1];
+	}
 
 	/*
 	 * deal with the case where there is only one pointer in the root
@@ -1107,9 +1108,10 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
 	mid = path->nodes[level];
 	WARN_ON(btrfs_header_generation(mid) != trans->transid);
 
-	if (level < BTRFS_MAX_LEVEL - 1)
+	if (level < BTRFS_MAX_LEVEL - 1) {
 		parent = path->nodes[level + 1];
-	pslot = path->slots[level + 1];
+		pslot = path->slots[level + 1];
+	}
 
 	if (!parent)
 		return 1;