From 5c41f75d1b921b9eaf79588cdd3b22b00fb4ec52 Mon Sep 17 00:00:00 2001 From: Jeongjun Park Date: Tue, 22 Oct 2024 00:43:56 +0900 Subject: [PATCH] bcachefs: fix shift oob in alloc_lru_idx_fragmentation The size of a.data_type is set abnormally large, causing shift-out-of-bounds. To fix this, we need to add validation on a.data_type in alloc_lru_idx_fragmentation(). Reported-by: syzbot+7f45fa9805c40db3f108@syzkaller.appspotmail.com Fixes: 260af1562ec1 ("bcachefs: Kill alloc_v4.fragmentation_lru") Signed-off-by: Jeongjun Park Signed-off-by: Kent Overstreet --- fs/bcachefs/alloc_background.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/bcachefs/alloc_background.h b/fs/bcachefs/alloc_background.h index f8e87c6721b1..163a67b97a40 100644 --- a/fs/bcachefs/alloc_background.h +++ b/fs/bcachefs/alloc_background.h @@ -168,6 +168,9 @@ static inline bool data_type_movable(enum bch_data_type type) static inline u64 alloc_lru_idx_fragmentation(struct bch_alloc_v4 a, struct bch_dev *ca) { + if (a.data_type >= BCH_DATA_NR) + return 0; + if (!data_type_movable(a.data_type) || !bch2_bucket_sectors_fragmented(ca, a)) return 0;