bcachefs: Fix early error path in bch2_fs_btree_key_cache_exit()

Reported-by: syzbot+a35cdb62ec34d44fb062@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/btree_key_cache.c b/fs/bcachefs/btree_key_cache.c
index e8c1c53..7dafa1a 100644 (file)
--- a/fs/bcachefs/btree_key_cache.c
+++ b/fs/bcachefs/btree_key_cache.c
@@ -956,13 +956,15 @@ void bch2_fs_btree_key_cache_exit(struct btree_key_cache *bc)
        }
 
 #ifdef __KERNEL__
-       for_each_possible_cpu(cpu) {
-               struct btree_key_cache_freelist *f =
-                       per_cpu_ptr(bc->pcpu_freed, cpu);
-
-               for (i = 0; i < f->nr; i++) {
-                       ck = f->objs[i];
-                       list_add(&ck->list, &items);
+       if (bc->pcpu_freed) {
+               for_each_possible_cpu(cpu) {
+                       struct btree_key_cache_freelist *f =
+                               per_cpu_ptr(bc->pcpu_freed, cpu);
+
+                       for (i = 0; i < f->nr; i++) {
+                               ck = f->objs[i];
+                               list_add(&ck->list, &items);
+                       }
                }
        }
 #endif