maynuo-m97: fix potential NULL dereference

Check pointers' validity before dereferencing them.

This was reported by clang's scan-build.

diff --git a/src/hardware/maynuo-m97/api.c b/src/hardware/maynuo-m97/api.c
index ebc0ddab85a96bd81ce7f1e416215ead5dd878da..0e593938eb4c15f74f3957a60f7a89912dffbbc3 100644 (file)
--- a/src/hardware/maynuo-m97/api.c
+++ b/src/hardware/maynuo-m97/api.c
@@ -363,9 +363,13 @@ static int config_list(uint32_t key, GVariant **data,
                        *data = std_gvar_array_u32(ARRAY_AND_SIZE(devopts_cg));
                        break;
                case SR_CONF_VOLTAGE_TARGET:
+                       if (!devc || !devc->model)
+                               return SR_ERR_ARG;
                        *data = std_gvar_min_max_step(0.0, devc->model->max_voltage, 0.001);
                        break;
                case SR_CONF_CURRENT_LIMIT:
+                       if (!devc || !devc->model)
+                               return SR_ERR_ARG;
                        *data = std_gvar_min_max_step(0.0, devc->model->max_current, 0.0001);
                        break;
                default: