f2fs: fix a problem of using memory after free

commit 7855eba4d6102f811b6dd142d6c749f53b591fa3 upstream.

This patch fix a problem of using memory after free
in function __try_merge_extent_node.

Fixes: 0f825ee6e873 ("f2fs: add new interfaces for extent tree")
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Yunlei He 2016-12-19 20:10:48 +08:00 committed by Greg Kroah-Hartman
parent d78f93384d
commit ec160ad2ac

View File

@ -352,11 +352,12 @@ static struct extent_node *__try_merge_extent_node(struct inode *inode,
}
if (next_ex && __is_front_mergeable(ei, &next_ex->ei)) {
if (en)
__release_extent_node(sbi, et, prev_ex);
next_ex->ei.fofs = ei->fofs;
next_ex->ei.blk = ei->blk;
next_ex->ei.len += ei->len;
if (en)
__release_extent_node(sbi, et, prev_ex);
en = next_ex;
}