From: Johannes Berg <johannes.berg@xxxxxxxxx> Linus reported that due to mac80211 failing to register the device (due to WoWLAN) his machine crashed etc. as we double-freed the vmalloc() firmware area. His patch to fix it was very similar to this one but I noticed that there's another bug in the area: we complete the completion before starting, so since we're running in a work struct context stop() could be called while in the middle of start() which will almost certainly lead to issues. Make a modification similar to his to avoid the double- free but also move the completion to another spot so it is only done after start() either finished or failed so that stop() can have a consistent state. Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> --- drivers/net/wireless/iwlwifi/iwl-drv.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/iwl-drv.c b/drivers/net/wireless/iwlwifi/iwl-drv.c index d742900..38fbbe7 100644 --- a/drivers/net/wireless/iwlwifi/iwl-drv.c +++ b/drivers/net/wireless/iwlwifi/iwl-drv.c @@ -861,13 +861,18 @@ static void iwl_ucode_callback(const struct firmware *ucode_raw, void *context) /* We have our copies now, allow OS release its copies */ release_firmware(ucode_raw); - complete(&drv->request_firmware_complete); drv->op_mode = iwl_dvm_ops.start(drv->trans, drv->cfg, &drv->fw); if (!drv->op_mode) - goto out_free_fw; + goto out_unbind; + /* + * Complete the firmware request last so that + * a driver unbind (stop) doesn't run while we + * are doing the start() above. + */ + complete(&drv->request_firmware_complete); return; try_again: @@ -883,6 +888,7 @@ static void iwl_ucode_callback(const struct firmware *ucode_raw, void *context) release_firmware(ucode_raw); out_unbind: complete(&drv->request_firmware_complete); + out_release_driver: device_release_driver(drv->trans->dev); } -- 1.7.10 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
