optee: add error checks in optee_ffa_do_call_with_arg()

Adds error checking in optee_ffa_do_call_with_arg() for correctness.

Fixes: 4615e5a34b95 ("optee: add FF-A support")
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

diff --git a/drivers/tee/optee/ffa_abi.c b/drivers/tee/optee/ffa_abi.c
index 20a1b1a..0775759 100644 (file)
--- a/drivers/tee/optee/ffa_abi.c
+++ b/drivers/tee/optee/ffa_abi.c
@@ -619,9 +619,18 @@ static int optee_ffa_do_call_with_arg(struct tee_context *ctx,
                .data2 = (u32)(shm->sec_world_id >> 32),
                .data3 = shm->offset,
        };
-       struct optee_msg_arg *arg = tee_shm_get_va(shm, 0);
-       unsigned int rpc_arg_offs = OPTEE_MSG_GET_ARG_SIZE(arg->num_params);
-       struct optee_msg_arg *rpc_arg = tee_shm_get_va(shm, rpc_arg_offs);
+       struct optee_msg_arg *arg;
+       unsigned int rpc_arg_offs;
+       struct optee_msg_arg *rpc_arg;
+
+       arg = tee_shm_get_va(shm, 0);
+       if (IS_ERR(arg))
+               return PTR_ERR(arg);
+
+       rpc_arg_offs = OPTEE_MSG_GET_ARG_SIZE(arg->num_params);
+       rpc_arg = tee_shm_get_va(shm, rpc_arg_offs);
+       if (IS_ERR(rpc_arg))
+               return PTR_ERR(rpc_arg);
 
        return optee_ffa_yielding_call(ctx, &data, rpc_arg);
 }