From: Johannes Berg Subject: [PATCH] iwlwifi: fix use-after-free Date: Tue, 8 Feb 2022 11:47:30 +0100 Content-Type: text/plain; charset=UTF-8 Message-Id: <20220208114728.e6b514cf4c85.Iffb575ca2a623d7859b542c33b2a507d01554251@changeid> List-ID: From: Johannes Berg If no firmware was present at all (or, presumably, all of the firmware files failed to parse), we end up unbinding by calling device_release_driver(), which calls remove(), which then in iwlwifi calls iwl_drv_stop(), freeing the 'drv' struct. However the new code I added will still erroneously access it after it was freed. Set 'failure=false' in this case to avoid the access, all data was already freed anyway. Cc: stable@vger.kernel.org Reported-by: Stefan Agner Reported-by: Wolfgang Walter Reported-by: Jason Self Reported-by: Dominik Behr Reported-by: Marek Marczykowski-Górecki Fixes: ab07506b0454 ("iwlwifi: fix leaks/bad data after failed firmware load") Signed-off-by: Johannes Berg --- drivers/net/wireless/intel/iwlwifi/iwl-drv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-drv.c b/drivers/net/wireless/intel/iwlwifi/iwl-drv.c index 83e3b731ad29..6651e78b39ec 100644 --- a/drivers/net/wireless/intel/iwlwifi/iwl-drv.c +++ b/drivers/net/wireless/intel/iwlwifi/iwl-drv.c @@ -1707,6 +1707,8 @@ static void iwl_req_fw_callback(const struct firmware *ucode_raw, void *context) out_unbind: complete(&drv->request_firmware_complete); device_release_driver(drv->trans->dev); + /* drv has just been freed by the release */ + failure = false; free: if (failure) iwl_dealloc_ucode(drv); -- 2.34.1