On 01/06/2023 05:33, Trevor Wu wrote:
During mt8195_afe_init_clock(), mt8195_audsys_clk_register() was called followed by several other devm functions. At mt8195_afe_deinit_clock() located at mt8195_afe_pcm_dev_remove(), mt8195_audsys_clk_unregister() was called. However, there was an issue with the order in which these functions were called. Specifically, the remove callback of platform_driver was called before devres released the resource, resulting in a use-after-free issue during remove time. At probe time, the order of calls was: 1. mt8195_audsys_clk_register 2. afe_priv->clk = devm_kcalloc 3. afe_priv->clk[i] = devm_clk_get At remove time, the order of calls was: 1. mt8195_audsys_clk_unregister 3. free afe_priv->clk[i] 2. free afe_priv->clk To resolve the problem, we can utilize devm_add_action_or_reset() in mt8195_audsys_clk_register() so that the remove order can be changed to 3->2->1.
Reviewed-by: Alexandre Mergnat <amergnat@xxxxxxxxxxxx> -- Regards, Alexandre
