diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index e9176a5ce215..98354d781678 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -9149,10 +9149,11 @@ static int check_reg_const_str(struct bpf_verifier_env *env,
 	return 0;
 }
 
-/* Returns constant key value if possible, else negative error */
-static s64 get_constant_map_key(struct bpf_verifier_env *env,
+/* Returns constant key value in `value` if possible, else negative error */
+static int get_constant_map_key(struct bpf_verifier_env *env,
 				struct bpf_reg_state *key,
-				u32 key_size)
+				u32 key_size,
+				s64 *value)
 {
 	struct bpf_func_state *state = func(env, key);
 	struct bpf_reg_state *reg;
@@ -9179,8 +9180,10 @@ static s64 get_constant_map_key(struct bpf_verifier_env *env,
 	/* First handle precisely tracked STACK_ZERO */
 	for (i = off; i >= 0 && stype[i] == STACK_ZERO; i--)
 		zero_size++;
-	if (zero_size >= key_size)
+	if (zero_size >= key_size) {
+		*value = 0;
 		return 0;
+	}
 
 	/* Check that stack contains a scalar spill of expected size */
 	if (!is_spilled_scalar_reg(&state->stack[spi]))
@@ -9203,7 +9206,8 @@ static s64 get_constant_map_key(struct bpf_verifier_env *env,
 	if (err < 0)
 		return err;
 
-	return reg->var_off.value;
+	*value = reg->var_off.value;
+	return 0;
 }
 
 static bool can_elide_value_nullness(enum bpf_map_type type);
@@ -9357,9 +9361,14 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg,
 		if (err)
 			return err;
 		if (can_elide_value_nullness(meta->map_ptr->map_type)) {
-			meta->const_map_key = get_constant_map_key(env, reg, key_size);
-			if (meta->const_map_key < 0 && meta->const_map_key != -EOPNOTSUPP)
-				return meta->const_map_key;
+			err = get_constant_map_key(env, reg, key_size, &meta->const_map_key);
+			if (err < 0) {
+				meta->const_map_key = -1;
+				if (err == -EOPNOTSUPP)
+					err = 0;
+				else
+					return err;
+			}
 		}
 		break;
 	case ARG_PTR_TO_MAP_VALUE: