From: Kent Overstreet <kent.overstreet@gmail.com>
Date: Sun, 10 Apr 2022 18:36:10 +0000 (-0400)
Subject: bcachefs: Fix a null ptr deref
X-Git-Tag: v6.7-rc1~201^2~989
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6e811bbbc2ea3b20854c45fa29811640881bb534;p=thirdparty%2Fkernel%2Flinux.git

bcachefs: Fix a null ptr deref

We start doing allocations before the GC thread is created, which means
we need to check for that to avoid a null ptr deref.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
---

diff --git a/fs/bcachefs/btree_gc.h b/fs/bcachefs/btree_gc.h
index 8de54005e4eaf..95d803b5743de 100644
--- a/fs/bcachefs/btree_gc.h
+++ b/fs/bcachefs/btree_gc.h
@@ -105,7 +105,8 @@ static inline bool gc_visited(struct bch_fs *c, struct gc_pos pos)
 static inline void bch2_do_gc_gens(struct bch_fs *c)
 {
 	atomic_inc(&c->kick_gc);
-	wake_up_process(c->gc_thread);
+	if (c->gc_thread)
+		wake_up_process(c->gc_thread);
 }
 
 #endif /* _BCACHEFS_BTREE_GC_H */