Add defensive assertions

cmd/zdb/zdb_il.c

@@ -182,6 +182,7 @@ zil_prt_rec_write(zilog_t *zilog, int txtype, const void *arg)
 			return;
 		}
 
+		ASSERT3U(BP_GET_LSIZE(bp), !=, 0);
 		SET_BOOKMARK(&zb, dmu_objset_id(zilog->zl_os),
 		    lr->lr_foid, ZB_ZIL_LEVEL,
 		    lr->lr_offset / BP_GET_LSIZE(bp));

module/os/freebsd/zfs/zfs_acl.c

@@ -1133,6 +1133,7 @@ zfs_acl_data_locator(void **dataptr, uint32_t *length, uint32_t buflen,
 		cb->cb_acl_node = list_next(&cb->cb_aclp->z_acl,
 		    cb->cb_acl_node);
 	}
+	ASSERT3P(cb->cb_acl_node, !=, NULL);
 	*dataptr = cb->cb_acl_node->z_acldata;
 	*length = cb->cb_acl_node->z_size;
 }

module/os/linux/zfs/zfs_acl.c

@@ -1163,6 +1163,7 @@ zfs_acl_data_locator(void **dataptr, uint32_t *length, uint32_t buflen,
 		cb->cb_acl_node = list_next(&cb->cb_aclp->z_acl,
 		    cb->cb_acl_node);
 	}
+	ASSERT3P(cb->cb_acl_node, !=, NULL);
 	*dataptr = cb->cb_acl_node->z_acldata;
 	*length = cb->cb_acl_node->z_size;
 }

module/zfs/arc.c

@@ -8539,6 +8539,7 @@ l2arc_dev_get_next(void)
 		else if (next == first)
 			break;
 
+		ASSERT3P(next, !=, NULL);
 	} while (vdev_is_dead(next->l2ad_vdev) || next->l2ad_rebuild ||
 	    next->l2ad_trim_all);
 

module/zfs/dbuf.c

@@ -2687,6 +2687,7 @@ dbuf_override_impl(dmu_buf_impl_t *db, const blkptr_t *bp, dmu_tx_t *tx)
 	dbuf_dirty_record_t *dr;
 
 	dr = list_head(&db->db_dirty_records);
+	ASSERT3P(dr, !=, NULL);
 	ASSERT3U(dr->dr_txg, ==, tx->tx_txg);
 	dl = &dr->dt.dl;
 	dl->dr_overridden_by = *bp;
@@ -2748,6 +2749,7 @@ dmu_buf_write_embedded(dmu_buf_t *dbuf, void *data,
 	dmu_buf_will_not_fill(dbuf, tx);
 
 	dr = list_head(&db->db_dirty_records);
+	ASSERT3P(dr, !=, NULL);
 	ASSERT3U(dr->dr_txg, ==, tx->tx_txg);
 	dl = &dr->dt.dl;
 	encode_embedded_bp_compressed(&dl->dr_overridden_by,

module/zfs/dmu_traverse.c

@@ -111,6 +111,7 @@ traverse_zil_record(zilog_t *zilog, const lr_t *lrc, void *arg,
 		if (claim_txg == 0 || bp->blk_birth < claim_txg)
 			return (0);
 
+		ASSERT3U(BP_GET_LSIZE(bp), !=, 0);
 		SET_BOOKMARK(&zb, td->td_objset, lr->lr_foid,
 		    ZB_ZIL_LEVEL, lr->lr_offset / BP_GET_LSIZE(bp));
 

module/zfs/dsl_deadlist.c

@@ -542,6 +542,7 @@ dsl_deadlist_remove_key(dsl_deadlist_t *dl, uint64_t mintxg, dmu_tx_t *tx)
 	dle = avl_find(&dl->dl_tree, &dle_tofind, NULL);
 	ASSERT3P(dle, !=, NULL);
 	dle_prev = AVL_PREV(&dl->dl_tree, dle);
+	ASSERT3P(dle_prev, !=, NULL);
 
 	dle_enqueue_subobj(dl, dle_prev, dle->dle_bpobj.bpo_object, tx);
 

module/zfs/dsl_scan.c

@@ -1470,6 +1470,7 @@ dsl_scan_zil_record(zilog_t *zilog, const lr_t *lrc, void *arg,
 		if (claim_txg == 0 || bp->blk_birth < claim_txg)
 			return (0);
 
+		ASSERT3U(BP_GET_LSIZE(bp), !=, 0);
 		SET_BOOKMARK(&zb, zh->zh_log.blk_cksum.zc_word[ZIL_ZC_OBJSET],
 		    lr->lr_foid, ZB_ZIL_LEVEL,
 		    lr->lr_offset / BP_GET_LSIZE(bp));

module/zfs/mmp.c

@@ -303,8 +303,10 @@ mmp_next_leaf(spa_t *spa)
 
 	do {
 		leaf = list_next(&spa->spa_leaf_list, leaf);
-		if (leaf == NULL)
+		if (leaf == NULL) {
 			leaf = list_head(&spa->spa_leaf_list);
+			ASSERT3P(leaf, !=, NULL);
+		}
 
 		/*
 		 * We skip unwritable, offline, detached, and dRAID spare

module/zfs/range_tree.c

@@ -369,6 +369,7 @@ range_tree_add_impl(void *arg, uint64_t start, uint64_t size, uint64_t fill)
 		 * invalid as soon as we do any mutating btree operations.
 		 */
 		rs_after = zfs_btree_find(&rt->rt_root, &tmp, &where_after);
+		ASSERT3P(rs_after, !=, NULL);
 		rs_set_start_raw(rs_after, rt, before_start);
 		rs_set_fill(rs_after, rt, after_fill + before_fill + fill);
 		rs = rs_after;

module/zfs/spa_log_spacemap.c

@@ -507,6 +507,7 @@ void
 spa_log_summary_decrement_blkcount(spa_t *spa, uint64_t blocks_gone)
 {
 	log_summary_entry_t *e = list_head(&spa->spa_log_summary);
+	ASSERT3P(e, !=, NULL);
 	if (e->lse_txgcount > 0)
 		e->lse_txgcount--;
 	for (; e != NULL; e = list_head(&spa->spa_log_summary)) {

module/zfs/vdev_indirect.c

@@ -1319,6 +1319,7 @@ vdev_indirect_io_start(zio_t *zio)
 	    vdev_indirect_gather_splits, zio);
 
 	indirect_split_t *first = list_head(&iv->iv_splits);
+	ASSERT3P(first, !=, NULL);
 	if (first->is_size == zio->io_size) {
 		/*
 		 * This is not a split block; we are pointing to the entire

module/zfs/vdev_queue.c

@@ -756,6 +756,7 @@ vdev_queue_aggregate(vdev_queue_t *vq, zio_t *zio)
 	do {
 		dio = nio;
 		nio = AVL_NEXT(t, dio);
+		ASSERT3P(dio, !=, NULL);
 		zio_add_child(dio, aio);
 		vdev_queue_io_remove(vq, dio);
 

module/zfs/zil.c

@@ -339,6 +339,7 @@ zil_read_log_data(zilog_t *zilog, const lr_write_t *lr, void *wbuf)
 	if (wbuf == NULL)
 		zio_flags |= ZIO_FLAG_RAW;
 
+	ASSERT3U(BP_GET_LSIZE(bp), !=, 0);
 	SET_BOOKMARK(&zb, dmu_objset_id(zilog->zl_os), lr->lr_foid,
 	    ZB_ZIL_LEVEL, lr->lr_offset / BP_GET_LSIZE(bp));