f2fs: fix not to allocate max_nid

The build_free_nid should not add free nids over nm_i->max_nid. But, there was a hole that invalid free nid was added by the following scenario. Let's suppose nm_i->max_nid = 150 and the last NAT page has 100 ~ 200 nids. build_free_nids - get_current_nat_page loads the last NAT page - scan_nat_page can add 100 ~ 200 nids -> Bug here! So, when scanning an NAT page, we should check each candidate whether it is over max_nid or not. Reviewed-by: Namjae Jeon <[email protected]> Signed-off-by: Jaegeuk Kim <[email protected]>
Baughn · Mar 20, 2013 · 04431c4 · 04431c4
1 parent c3850aa
commit 04431c4
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
@@ -1268,6 +1268,8 @@ static int scan_nat_page(struct f2fs_nm_info *nm_i,
 	i = start_nid % NAT_ENTRY_PER_BLOCK;
 
 	for (; i < NAT_ENTRY_PER_BLOCK; i++, start_nid++) {
+		if (start_nid >= nm_i->max_nid)
+			break;
 		blk_addr  = le32_to_cpu(nat_blk->entries[i].block_addr);
 		BUG_ON(blk_addr == NEW_ADDR);
 		if (blk_addr == NULL_ADDR)