[PATCH] bcachefs: Add error handling for bch2_folio()

[Wentao Liang]

Add error handling for the case where bch2_folio() returns NULL
in __bch2_folio_set(). Return immediately to prevent null pointer
dereference.

Signed-off-by: Wentao Liang <vulab@xxxxxxxxxxx>
---
 fs/bcachefs/fs-io-pagecache.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/bcachefs/fs-io-pagecache.c b/fs/bcachefs/fs-io-pagecache.c
index e072900e6a5b..1dc65fef3ff4 100644
--- a/fs/bcachefs/fs-io-pagecache.c
+++ b/fs/bcachefs/fs-io-pagecache.c
@@ -159,6 +159,9 @@ static void __bch2_folio_set(struct folio *folio,
 	struct bch_folio *s = bch2_folio(folio);
 	unsigned i, sectors = folio_sectors(folio);
 
+	if (!s)
+		return;
+
 	BUG_ON(pg_offset >= sectors);
 	BUG_ON(pg_offset + pg_len > sectors);
 
-- 
2.42.0.windows.2