From: Dave Kleikamp Date: Fri, 28 Oct 2005 18:27:40 +0000 (-0500) Subject: JFS: make sure right-most xtree pages have header.next set to zero X-Git-Tag: firefly_0821_release~40855^2~29^2 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=7038f1cbac899654cf0515e60dbe3e44d58271de;p=firefly-linux-kernel-4.4.55.git 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 --- diff --git a/fs/jfs/jfs_xtree.c b/fs/jfs/jfs_xtree.c index a7fe2f2b969f..e72f4ebb6e9c 100644 --- a/fs/jfs/jfs_xtree.c +++ b/fs/jfs/jfs_xtree.c @@ -3516,16 +3516,10 @@ s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int flag) /* 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 @@ s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int flag) p->header.next = 0; } + if (p->header.flag & BT_INTERNAL) + goto getChild; + + /* + * leaf page + */ freed = 0; /* does region covered by leaf page precede Teof ? */