bcachefs: Fix btree iterator leak in extent_handle_overwrites()

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

diff --git a/fs/bcachefs/btree_update_leaf.c b/fs/bcachefs/btree_update_leaf.c
index bf2a2b0695b6738c9bcea742daf0f4859d783932..f8b493706c949d346d2882502a5ad3b0d5b2ab44 100644 (file)
--- a/fs/bcachefs/btree_update_leaf.c
+++ b/fs/bcachefs/btree_update_leaf.c
@@ -754,7 +754,7 @@ static int extent_handle_overwrites(struct btree_trans *trans,
                                    enum btree_id btree_id,
                                    struct bpos start, struct bpos end)
 {
-       struct btree_iter *iter = NULL, *update_iter;
+       struct btree_iter *iter, *update_iter;
        struct bkey_i *update;
        struct bkey_s_c k;
        int ret = 0;
@@ -767,8 +767,6 @@ static int extent_handle_overwrites(struct btree_trans *trans,
                        break;
 
                if (bkey_cmp(bkey_start_pos(k.k), start) < 0) {
-                       update_iter = bch2_trans_copy_iter(trans, iter);
-
                        update = bch2_trans_kmalloc(trans, bkey_bytes(k.k));
                        if ((ret = PTR_ERR_OR_ZERO(update)))
                                goto err;
@@ -776,6 +774,7 @@ static int extent_handle_overwrites(struct btree_trans *trans,
                        bkey_reassemble(update, k);
                        bch2_cut_back(start, update);
 
+                       update_iter = bch2_trans_copy_iter(trans, iter);
                        update_iter->flags &= ~BTREE_ITER_IS_EXTENTS;
                        bch2_btree_iter_set_pos(update_iter, update->k.p);
                        ret = bch2_trans_update2(trans, update_iter, update);
@@ -785,8 +784,6 @@ static int extent_handle_overwrites(struct btree_trans *trans,
                }
 
                if (bkey_cmp(k.k->p, end) > 0) {
-                       update_iter = bch2_trans_copy_iter(trans, iter);
-
                        update = bch2_trans_kmalloc(trans, bkey_bytes(k.k));
                        if ((ret = PTR_ERR_OR_ZERO(update)))
                                goto err;
@@ -794,6 +791,7 @@ static int extent_handle_overwrites(struct btree_trans *trans,
                        bkey_reassemble(update, k);
                        bch2_cut_front(end, update);
 
+                       update_iter = bch2_trans_copy_iter(trans, iter);
                        update_iter->flags &= ~BTREE_ITER_IS_EXTENTS;
                        bch2_btree_iter_set_pos(update_iter, update->k.p);
                        ret = bch2_trans_update2(trans, update_iter, update);
@@ -801,8 +799,6 @@ static int extent_handle_overwrites(struct btree_trans *trans,
                        if (ret)
                                goto err;
                } else {
-                       update_iter = bch2_trans_copy_iter(trans, iter);
-
                        update = bch2_trans_kmalloc(trans, sizeof(struct bkey));
                        if ((ret = PTR_ERR_OR_ZERO(update)))
                                goto err;
@@ -812,6 +808,7 @@ static int extent_handle_overwrites(struct btree_trans *trans,
                        update->k.type = KEY_TYPE_deleted;
                        update->k.size = 0;
 
+                       update_iter = bch2_trans_copy_iter(trans, iter);
                        update_iter->flags &= ~BTREE_ITER_IS_EXTENTS;
                        bch2_btree_iter_set_pos(update_iter, update->k.p);
                        ret = bch2_trans_update2(trans, update_iter, update);
@@ -823,8 +820,7 @@ static int extent_handle_overwrites(struct btree_trans *trans,
                k = bch2_btree_iter_next_with_updates(iter);
        }
 err:
-       if (!IS_ERR_OR_NULL(iter))
-               bch2_trans_iter_put(trans, iter);
+       bch2_trans_iter_put(trans, iter);
        return ret;
 }