lib: increase refcount when returning cached module instance

Subsequent requires of the same module returned the cached module instance
without increasing the refcount, leading to use-after-free on VM tear down
or garbage collection cycles.

Solve this issue by properly incrementing the refcount before returning
the cached module instance.

Fixes: #25
Fixes: 96f140b ("lib, vm: ensure that require() compiles modules only once")
Signed-off-by: Jo-Philipp Wich <jo@mein.io>

1 files changed, 1 insertions, 1 deletions

diff --git a/lib.c b/lib.c
index 0b1f663..2c91d1d 100644
--- a/lib.c
+++ b/lib.c
@@ -1597,7 +1597,7 @@ uc_require_path(uc_vm_t *vm, const char *path_template, const char *name, uc_val
 	bool rv;
 
 	modtable = ucv_property_get(uc_vm_scope_get(vm), "modules");
-	*res = ucv_object_get(modtable, name, &rv);
+	*res = ucv_get(ucv_object_get(modtable, name, &rv));
 
 	if (rv)
 		goto out;