JFS: make sure right-most xtree pages have header.next set to zero
The xtTruncate code was only doing this for leaf pages. When a file is
horribly fragmented, we may truncate a file leaving an internal page with
an invalid head.next field, which may cause a stale page to be referenced.
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
diff --git a/fs/jfs/jfs_xtree.c b/fs/jfs/jfs_xtree.c
index a7fe2f2..e72f4eb 100644
--- a/fs/jfs/jfs_xtree.c
+++ b/fs/jfs/jfs_xtree.c
@@ -3516,16 +3516,10 @@
/* process entries backward from last index */
index = le16_to_cpu(p->header.nextindex) - 1;
- if (p->header.flag & BT_INTERNAL)
- goto getChild;
- /*
- * leaf page
- */
-
- /* Since this is the rightmost leaf, and we may have already freed
- * a page that was formerly to the right, let's make sure that the
- * next pointer is zero.
+ /* Since this is the rightmost page at this level, and we may have
+ * already freed a page that was formerly to the right, let's make
+ * sure that the next pointer is zero.
*/
if (p->header.next) {
if (log)
@@ -3539,6 +3533,12 @@
p->header.next = 0;
}
+ if (p->header.flag & BT_INTERNAL)
+ goto getChild;
+
+ /*
+ * leaf page
+ */
freed = 0;
/* does region covered by leaf page precede Teof ? */