f2fs: fix to handle looped node chain during recovery

There is no checksum in node block now, so bit-transition from hardware
can make node_footer.next_blkaddr being corrupted w/o any detection,
result in node chain becoming looped one.

For this condition, during recovery, in order to avoid running into dead
loop, let's detect it and just skip out.

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Chao Yu 2018-02-03 17:44:39 +08:00 committed by Jaegeuk Kim
parent 0f9ec2a8f6
commit fb0e72c8b9
1 changed files with 14 additions and 0 deletions

View File

@ -242,6 +242,9 @@ static int find_fsync_dnodes(struct f2fs_sb_info *sbi, struct list_head *head,
struct curseg_info *curseg;
struct page *page = NULL;
block_t blkaddr;
unsigned int loop_cnt = 0;
unsigned int free_blocks = sbi->user_block_count -
valid_user_blocks(sbi);
int err = 0;
/* get node pages in the current segment */
@ -294,6 +297,17 @@ static int find_fsync_dnodes(struct f2fs_sb_info *sbi, struct list_head *head,
if (IS_INODE(page) && is_dent_dnode(page))
entry->last_dentry = blkaddr;
next:
/* sanity check in order to detect looped node chain */
if (++loop_cnt >= free_blocks ||
blkaddr == next_blkaddr_of_node(page)) {
f2fs_msg(sbi->sb, KERN_NOTICE,
"%s: detect looped node chain, "
"blkaddr:%u, next:%u",
__func__, blkaddr, next_blkaddr_of_node(page));
err = -EINVAL;
break;
}
/* check next segment */
blkaddr = next_blkaddr_of_node(page);
f2fs_put_page(page, 1);