Commit abbfc4db authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: Add check for btree_path ref overflow 



Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent 094c6a9f

fs/bcachefs/btree_iter.c

+12 −12
Original line number Diff line number Diff line
@@ -1010,9 +1010,9 @@ static int bch2_btree_path_traverse_all(struct btree_trans *trans) 
		 * the same position:

		 */

		if (trans->paths[idx].uptodate) {

			__btree_path_get(&trans->paths[idx], false);

			__btree_path_get(trans, &trans->paths[idx], false);

			ret = bch2_btree_path_traverse_one(trans, idx, 0, _THIS_IP_);

			__btree_path_put(&trans->paths[idx], false);

			__btree_path_put(trans, &trans->paths[idx], false);



			if (bch2_err_matches(ret, BCH_ERR_transaction_restart) ||

			    bch2_err_matches(ret, ENOMEM))
@@ -1225,7 +1225,7 @@ static btree_path_idx_t btree_path_clone(struct btree_trans *trans, btree_path_i 
{

	btree_path_idx_t new = btree_path_alloc(trans, src);

	btree_path_copy(trans, trans->paths + new, trans->paths + src);

	__btree_path_get(trans->paths + new, intent);

	__btree_path_get(trans, trans->paths + new, intent);

#ifdef TRACK_PATH_ALLOCATED

	trans->paths[new].ip_allocated = ip;

#endif
@@ -1236,7 +1236,7 @@ __flatten 
btree_path_idx_t __bch2_btree_path_make_mut(struct btree_trans *trans,

			btree_path_idx_t path, bool intent, unsigned long ip)

{

	__btree_path_put(trans->paths + path, intent);

	__btree_path_put(trans, trans->paths + path, intent);

	path = btree_path_clone(trans, path, intent, ip);

	trans->paths[path].preserve = false;

	return path;
@@ -1361,7 +1361,7 @@ void bch2_path_put(struct btree_trans *trans, btree_path_idx_t path_idx, bool in 
{

	struct btree_path *path = trans->paths + path_idx, *dup;



	if (!__btree_path_put(path, intent))

	if (!__btree_path_put(trans, path, intent))

		return;



	dup = path->preserve
@@ -1392,7 +1392,7 @@ void bch2_path_put(struct btree_trans *trans, btree_path_idx_t path_idx, bool in 
static void bch2_path_put_nokeep(struct btree_trans *trans, btree_path_idx_t path,

				 bool intent)

{

	if (!__btree_path_put(trans->paths + path, intent))

	if (!__btree_path_put(trans, trans->paths + path, intent))

		return;



	__bch2_path_free(trans, path);
@@ -1716,14 +1716,14 @@ btree_path_idx_t bch2_path_get(struct btree_trans *trans, 
	    trans->paths[path_pos].cached	== cached &&

	    trans->paths[path_pos].btree_id	== btree_id &&

	    trans->paths[path_pos].level	== level) {

		__btree_path_get(trans->paths + path_pos, intent);

		__btree_path_get(trans, trans->paths + path_pos, intent);

		path_idx = bch2_btree_path_set_pos(trans, path_pos, pos, intent, ip);

		path = trans->paths + path_idx;

	} else {

		path_idx = btree_path_alloc(trans, path_pos);

		path = trans->paths + path_idx;



		__btree_path_get(path, intent);

		__btree_path_get(trans, path, intent);

		path->pos			= pos;

		path->btree_id			= btree_id;

		path->cached			= cached;
@@ -2326,7 +2326,7 @@ struct bkey_s_c bch2_btree_iter_peek_upto(struct btree_iter *iter, struct bpos e 
			 * advance, same as on exit for iter->path, but only up

			 * to snapshot

			 */

			__btree_path_get(trans->paths + iter->path, iter->flags & BTREE_ITER_intent);

			__btree_path_get(trans, trans->paths + iter->path, iter->flags & BTREE_ITER_intent);

			iter->update_path = iter->path;



			iter->update_path = bch2_btree_path_set_pos(trans,
@@ -2911,9 +2911,9 @@ void bch2_trans_copy_iter(struct btree_iter *dst, struct btree_iter *src) 
	dst->ip_allocated = _RET_IP_;

#endif

	if (src->path)

		__btree_path_get(trans->paths + src->path, src->flags & BTREE_ITER_intent);

		__btree_path_get(trans, trans->paths + src->path, src->flags & BTREE_ITER_intent);

	if (src->update_path)

		__btree_path_get(trans->paths + src->update_path, src->flags & BTREE_ITER_intent);

		__btree_path_get(trans, trans->paths + src->update_path, src->flags & BTREE_ITER_intent);

	dst->key_cache_path = 0;

}
@@ -3237,7 +3237,7 @@ void bch2_trans_put(struct btree_trans *trans) 
	bch2_trans_unlock(trans);



	trans_for_each_update(trans, i)

		__btree_path_put(trans->paths + i->path, true);

		__btree_path_put(trans, trans->paths + i->path, true);

	trans->nr_updates	= 0;



	check_btree_paths_leaked(trans);

fs/bcachefs/btree_iter.h

+18 −8
Original line number Diff line number Diff line
@@ -6,6 +6,12 @@ 
#include "btree_types.h"

#include "trace.h"



void bch2_trans_updates_to_text(struct printbuf *, struct btree_trans *);

void bch2_btree_path_to_text(struct printbuf *, struct btree_trans *, btree_path_idx_t);

void bch2_trans_paths_to_text(struct printbuf *, struct btree_trans *);

void bch2_dump_trans_updates(struct btree_trans *);

void bch2_dump_trans_paths_updates(struct btree_trans *);



static inline int __bkey_err(const struct bkey *k)

{

	return PTR_ERR_OR_ZERO(k);
@@ -13,16 +19,26 @@ static inline int __bkey_err(const struct bkey *k) 


#define bkey_err(_k)	__bkey_err((_k).k)



static inline void __btree_path_get(struct btree_path *path, bool intent)

static inline void __btree_path_get(struct btree_trans *trans, struct btree_path *path, bool intent)

{

	unsigned idx = path - trans->paths;



	EBUG_ON(!test_bit(idx, trans->paths_allocated));

	if (unlikely(path->ref == U8_MAX)) {

		bch2_dump_trans_paths_updates(trans);

		panic("path %u refcount overflow\n", idx);

	}



	path->ref++;

	path->intent_ref += intent;

}



static inline bool __btree_path_put(struct btree_path *path, bool intent)

static inline bool __btree_path_put(struct btree_trans *trans, struct btree_path *path, bool intent)

{

	EBUG_ON(!test_bit(path - trans->paths, trans->paths_allocated));

	EBUG_ON(!path->ref);

	EBUG_ON(!path->intent_ref && intent);



	path->intent_ref -= intent;

	return --path->ref == 0;

}
@@ -894,12 +910,6 @@ __bch2_btree_iter_peek_and_restart(struct btree_trans *trans, 
	_ret;								\

})



void bch2_trans_updates_to_text(struct printbuf *, struct btree_trans *);

void bch2_btree_path_to_text(struct printbuf *, struct btree_trans *, btree_path_idx_t);

void bch2_trans_paths_to_text(struct printbuf *, struct btree_trans *);

void bch2_dump_trans_updates(struct btree_trans *);

void bch2_dump_trans_paths_updates(struct btree_trans *);



struct btree_trans *__bch2_trans_get(struct bch_fs *, unsigned);

void bch2_trans_put(struct btree_trans *);

fs/bcachefs/btree_update.c

+1 −1
Original line number Diff line number Diff line
@@ -449,7 +449,7 @@ bch2_trans_update_by_path(struct btree_trans *trans, btree_path_idx_t path_idx, 
		}

	}



	__btree_path_get(trans->paths + i->path, true);

	__btree_path_get(trans, trans->paths + i->path, true);



	/*

	 * If a key is present in the key cache, it must also exist in the