rcu: Annotate struct kvfree_rcu_bulk_data with __counted_by()
Add the __counted_by compiler attribute to the flexible array member
records to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
CONFIG_FORTIFY_SOURCE.
Increment nr_records before adding a new pointer to the records array.
Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Reviewed-by: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 930846f..0c8b56c 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3207,7 +3207,7 @@ struct kvfree_rcu_bulk_data {
struct list_head list;
struct rcu_gp_oldstate gp_snap;
unsigned long nr_records;
- void *records[];
+ void *records[] __counted_by(nr_records);
};
/*
@@ -3747,7 +3747,8 @@ add_ptr_to_bulk_krc_lock(struct kfree_rcu_cpu **krcp,
}
// Finally insert and update the GP for this page.
- bnode->records[bnode->nr_records++] = ptr;
+ bnode->nr_records++;
+ bnode->records[bnode->nr_records - 1] = ptr;
get_state_synchronize_rcu_full(&bnode->gp_snap);
atomic_inc(&(*krcp)->bulk_count[idx]);
