| From 7855eba4d6102f811b6dd142d6c749f53b591fa3 Mon Sep 17 00:00:00 2001 |
| From: Yunlei He <heyunlei@huawei.com> |
| Date: Mon, 19 Dec 2016 20:10:48 +0800 |
| Subject: f2fs: fix a problem of using memory after free |
| |
| From: Yunlei He <heyunlei@huawei.com> |
| |
| 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> |
| |
| --- |
| fs/f2fs/extent_cache.c | 5 +++-- |
| 1 file changed, 3 insertions(+), 2 deletions(-) |
| |
| --- a/fs/f2fs/extent_cache.c |
| +++ b/fs/f2fs/extent_cache.c |
| @@ -352,11 +352,12 @@ static struct extent_node *__try_merge_e |
| } |
| |
| 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; |
| } |
| |
