Commit abf23afa authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: Fix btree node scan when unknown btree IDs are present 



btree_root entries for unknown btree IDs are created during recovery,
before reading those btree roots.

But btree_node_scan may find btree nodes with unknown btree IDs when we
haven't seen roots for those btrees.

Reported-by: default avatar <syzbot+1f202d4da221ec6ebf8e@syzkaller.appspotmail.com>
Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent 427db7ff

fs/bcachefs/btree_cache.c

+8 −3
Original line number Diff line number Diff line
@@ -1406,9 +1406,14 @@ void bch2_btree_id_level_to_text(struct printbuf *out, enum btree_id btree, unsi 
void bch2_btree_pos_to_text(struct printbuf *out, struct bch_fs *c, const struct btree *b)

{

	bch2_btree_id_to_text(out, b->c.btree_id);

	prt_printf(out, " level %u/%u\n  ",

		   b->c.level,

		   bch2_btree_id_root(c, b->c.btree_id)->level);

	prt_printf(out, " level %u/", b->c.level);

	struct btree_root *r = bch2_btree_id_root(c, b->c.btree_id);

	if (r)

		prt_printf(out, "%u", r->level);

	else

		prt_printf(out, "(unknown)");

	prt_printf(out, "\n  ");



	bch2_bkey_val_to_text(out, c, bkey_i_to_s_c(&b->key));

}

fs/bcachefs/btree_cache.h

+7 −2
Original line number Diff line number Diff line
@@ -128,14 +128,19 @@ static inline struct btree_root *bch2_btree_id_root(struct bch_fs *c, unsigned i 
	} else {

		unsigned idx = id - BTREE_ID_NR;



		EBUG_ON(idx >= c->btree_roots_extra.nr);

		/* This can happen when we're called from btree_node_scan */

		if (idx >= c->btree_roots_extra.nr)

			return NULL;



		return &c->btree_roots_extra.data[idx];

	}

}



static inline struct btree *btree_node_root(struct bch_fs *c, struct btree *b)

{

	return bch2_btree_id_root(c, b->c.btree_id)->b;

	struct btree_root *r = bch2_btree_id_root(c, b->c.btree_id);



	return r ? r->b : NULL;

}



const char *bch2_btree_id_str(enum btree_id);	/* avoid */