[PATCH v2 2/2] erofs-utils: more sanity check for buffer allocation optimization

[Gao Xiang]

From: Gao Xiang <hsiangkao at aol.com>

In case that new buffer allocation optimization logic is
potentially broken.

Signed-off-by: Gao Xiang <hsiangkao at aol.com>
---
changes since v1:
 - add a more check "used_before != cur->buffers.off % EROFS_BLKSIZ"

 lib/cache.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/cache.c b/lib/cache.c
index 6ae2b202e67b..340dcdd76ce3 100644
--- a/lib/cache.c
+++ b/lib/cache.c
@@ -186,8 +186,14 @@ static int erofs_bfind_for_attach(int type, erofs_off_t size,
 				       mapped_list);
 
 		/* last mapped block can be expended, don't handle it here */
-		if (cur == last_mapped_block)
+		if (list_next_entry(cur, list)->blkaddr == NULL_ADDR) {
+			DBG_BUGON(cur != last_mapped_block);
 			continue;
+		}
+
+		DBG_BUGON(cur->type != type);
+		DBG_BUGON(cur->blkaddr == NULL_ADDR);
+		DBG_BUGON(used_before != cur->buffers.off % EROFS_BLKSIZ);
 
 		ret = __erofs_battach(cur, NULL, size, alignsize,
 				      required_ext + inline_ext, true);
-- 
2.24.0