Re: [PATCH 2/2] HID: hid-steam: Fix cleanup in probe()

From: Vicki Pfau
Date: Fri Jan 12 2024 - 21:11:22 EST


I have applied this to our downstream and made sure it compiles and runs without obvious issues.

Reviewed-by: Vicki Pfau <vi@xxxxxxxxxxx>

Thanks,
Vicki

On 1/12/24 06:35, Dan Carpenter wrote:
There are a number of issues in this code. First of all if
steam_create_client_hid() fails then it leads to an error pointer
dereference when we call hid_destroy_device(steam->client_hdev).

Also there are a number of leaks. hid_hw_stop() is not called if
hid_hw_open() fails for example. And it doesn't call steam_unregister()
or hid_hw_close().

Fixes: 691ead124a0c ("HID: hid-steam: Clean up locking")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
This is just from static analysis and code review. I haven't tested
it. I only included the fixes tag for the error pointer dereference.

drivers/hid/hid-steam.c | 26 +++++++++++++++-----------
1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/drivers/hid/hid-steam.c b/drivers/hid/hid-steam.c
index 59df6ead7b54..b08a5ab58528 100644
--- a/drivers/hid/hid-steam.c
+++ b/drivers/hid/hid-steam.c
@@ -1128,14 +1128,14 @@ static int steam_probe(struct hid_device *hdev,
*/
ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_HIDRAW);
if (ret)
- goto hid_hw_start_fail;
+ goto err_cancel_work;
ret = hid_hw_open(hdev);
if (ret) {
hid_err(hdev,
"%s:hid_hw_open\n",
__func__);
- goto hid_hw_open_fail;
+ goto err_hw_stop;
}
if (steam->quirks & STEAM_QUIRK_WIRELESS) {
@@ -1151,33 +1151,37 @@ static int steam_probe(struct hid_device *hdev,
hid_err(hdev,
"%s:steam_register failed with error %d\n",
__func__, ret);
- goto input_register_fail;
+ goto err_hw_close;
}
}
steam->client_hdev = steam_create_client_hid(hdev);
if (IS_ERR(steam->client_hdev)) {
ret = PTR_ERR(steam->client_hdev);
- goto client_hdev_fail;
+ goto err_stream_unregister;
}
steam->client_hdev->driver_data = steam;
ret = hid_add_device(steam->client_hdev);
if (ret)
- goto client_hdev_add_fail;
+ goto err_destroy;
return 0;
-client_hdev_add_fail:
- hid_hw_stop(hdev);
-client_hdev_fail:
+err_destroy:
hid_destroy_device(steam->client_hdev);
-input_register_fail:
-hid_hw_open_fail:
-hid_hw_start_fail:
+err_stream_unregister:
+ if (steam->connected)
+ steam_unregister(steam);
+err_hw_close:
+ hid_hw_close(hdev);
+err_hw_stop:
+ hid_hw_stop(hdev);
+err_cancel_work:
cancel_work_sync(&steam->work_connect);
cancel_delayed_work_sync(&steam->mode_switch);
cancel_work_sync(&steam->rumble_work);
+
return ret;
}