module verification failed: signature and/or required key missing - tainting kernel

[Krbija]

hello

i'm follow the readme.txt install this driver on Ubuntu 18.04, but it's not work.

uname -a

Linux lxeo 5.4.0-45-generic #49~18.04.2-Ubuntu SMP Wed Aug 26 16:29:02 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

lsmod | grep ch34

ch34x                  24576  0
usbserial              49152  1 ch34x

dmesg | grep ch34

[   57.989423] ch34x: loading out-of-tree module taints kernel.
[   57.989477] ch34x: module verification failed: signature and/or required key missing - tainting kernel
[   57.989761] usbcore: registered new interface driver ch34x
[   57.989789] usbserial: USB Serial support registered for ch34x
[  269.528281] usbserial: USB Serial deregistering driver ch34x
[  269.528331] usbcore: deregistering interface driver ch34x
[  272.788150] usbcore: registered new interface driver ch34x
[  272.788168] usbserial: USB Serial support registered for ch34x

ls /dev/ttyUSB*

zsh: no matches found: /dev/ttyUSB*

[Jagoda Górska]

Even if you have the same warnings, check the work of module and tell me about results

[Xiaoqiao Chen]

Hello, I have the same problem here on Ubuntu 18.04. The module is successfully loaded:

However, it fails to convert my USB device to ttyUSB:

Is there any solutions? Thanks!

[hesaputra]

Did you sign the compiled ch34x.ko?

openssl req -new -x509 -newkey rsa:2048 -keyout MOK.priv -outform DER -out MOK.der -nodes -days 36500 -subj "/CN=Descriptive name/"

sudo /usr/src/linux-headers-$(uname -r)/scripts/sign-file sha256 ./MOK.priv ./MOK.der ch34x.ko

sudo mokutil --import MOK.der

Enter your password, reboot, then load the key

[Xiaoqiao Chen]

Did you sign the compiled ch34x.ko?

openssl req -new -x509 -newkey rsa:2048 -keyout MOK.priv -outform DER -out MOK.der -nodes -days 36500 -subj "/CN=Descriptive name/"

sudo /usr/src/linux-headers-$(uname -r)/scripts/sign-file sha256 ./MOK.priv ./MOK.der ch34x.ko

sudo mokutil --import MOK.der

Enter your password, reboot, then load the key

Thanks for your suggestion! Now the warning disappears but still no conversion is made:

Looks like the conversion problem is not related with the verification. Are there any other possible causes for the problem? The ch340 driver works for my device on Windows.

[hesaputra]

What device are you trying to connect to? the idVendor and idProduct from your screenshot don't seems to match with ch341x signature. Perhaps your device need another driver, not this one.
From the source code:
#define CH34x_VENDOR_ID 0x1A86

#define CH340_PRODUCT_ID 0x7523

#define CH341_PRODUCT_ID 0x5523

[Xiaoqiao Chen]

Thanks for your suggestion. Seems that I should look for other drivers.

[Jagoda Górska]

Thank you @hesaputra for help and sorry for being late. Closed.

[Humble Penguin]

How can I fix this on a Arch based system? The sign-file script is not available