Downgrade protection works only for the app_core -image-and not for the net-core -image

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Amanda Hsieh — Wed, 02 Apr 2025 19:21:07 GMT

Hi,

This discussion is not suitable for SDK 2.9.0. Please create a new support case for your issue.

-Amanda H.

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Esnoar@CicloSport — Wed, 02 Apr 2025 09:18:51 GMT

Hi!

I am following this issue because I have the same use case and I am trying to enable this configuration on the b0n image in the Network Core (nRF5340 as well) but I can not make this work. I am using sysbuild on SDK 2.9.0 so I guess it should be handled differently but can not figure out how.

Can you maybe explain to me where exactly should I add this configuration?

My NetCore image is "ipc_radio". I have tried adding

set(ipc_radio_b0n_CONFIG_PCD_READ_NETCORE_APP_VERSION y)

in sysbuild.cmake and CMakeLists.txt but nothing seems to work,

Thanks!

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Amanda Hsieh — Thu, 29 Aug 2024 13:05:13 GMT

Good to know it works, and thanks for the feedback. I will forward it to the internal.

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Thu, 29 Aug 2024 12:35:25 GMT

Hi,

thank you for your example. The example works as expected.

Our application is working now, too.

The problem was that I forgot to update the

CONFIG_FW_INFO_FIRMWARE_VERSION in child_image/hci_ipc.conf when creating a new version,

It would be be nice to add the issues we discussed here also on your homepage.

Downgrade protection (nordicsemi.com)

Thank your for the support.

Best Regards,

Georg

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Amanda Hsieh — Tue, 27 Aug 2024 21:19:37 GMT

Hi,

I add the following code in the main.c of zephyr\samples\bluetooth\hci_ipc\ to get version number:

	printk("Board config: %s\n", CONFIG_BOARD);
	printk("CONFIG_FW_INFO_FIRMWARE_VERSION: %d\n", CONFIG_FW_INFO_FIRMWARE_VERSION );
	printk("build time: " __DATE__ " " __TIME__ "\n");

I followed your steps to upgrade & downgrade, and got " insufficient version in secondary slot" and reverted to APP-Core = V2, NET-Core = V2

1. APP-Core = V1, NET-Core = V1

2. Fota Update with V2 Zip file

3. APP-Core = V2, NET-Core = V2

4. Fota Update with V1 dfu_application.zip or net_core_app_update.bin file (for downgrading)

=> Got " insufficient version in secondary slot" and reverted to APP-Core = V2, NET-Core = V2

Here is my test project devzone.nordicsemi.com/.../peripheral_5F00_lbs_5F00_downProtect.7z for NCS v2.6.1. specify Kconfig file for B0n with CMakeLists.txt.
West build and flash Command:

west build -p -b nrf5340dk_nrf5340_cpuapp -d build_nrf5340dk_nrf5340_cpuapp && west flash --build-dir build_nrf5340dk_nrf5340_cpuapp --recover

Beware that this code/configuration is not fully tested or qualified and should be considered provided “as-is”. Please test it with your application and let me know if you find any issues.

-Amanda H.

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Fri, 23 Aug 2024 14:04:59 GMT

Hi,

after deleting the build directory and creating a new V1 zip file and a new V2 zip file I got the same results as described in my last mail.

1. APP-Core = V1, NET-Core = V1

2. Fota Update with V2 Zip file

3. APP-Core = V2, NET-Core = V2

4. Fota Update with V1 Zip file (downgrading)

5. APP-Core = V2, NET Core= V1

The problem still exists.

After programming a new Version I always read out the memory of the nrf5340 and checked which version is programmed in the APP-Core and the NET-Core.

Do you have an example that works ?

Georg

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Amanda Hsieh — Thu, 22 Aug 2024 16:36:11 GMT

Hi,

Please try to delete the build folder and build again. It should work.

If you don't want to modify anything of the nrf\samples\nrf5340\netboot, you can build the project with this config for netboot(b0n)

-Dhci_ipc_b0n_CONFIG_PCD_READ_NETCORE_APP_VERSION=y

-Amanda H.

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Thu, 22 Aug 2024 15:32:36 GMT

Hi,

Ignore my last 2 messages

After adding CONFIG_PCD_READ_NETCORE_APP_VERSION=y to nrf\samples\nrf5340\netboot\prj.conf I see that `CONFIG_PCD_READ_NETCORE_APP_VERSION is set in hci_ipc/b0n/zephyr/.config

Now the application boots and Mcuboot doesn't hang in the "do while" loop.

But downgrade protection doesn't still work for the net core.

1. APP-Core = V1, NET-Core = V1

2. Fota Update with V2

3. APP-Core = V2, NET-Core = V2

4. Fota Update with V1 (downgrading)

5. APP-Core = V2, NET Core= V1

Best regards,

Georg

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Thu, 22 Aug 2024 11:40:30 GMT

Hi,

I set CONFIG_PCD_READ_NETCORE_APP_VERSION=y in nrf\samples\nrf5340\netboot\prj.conf

When loooking into MyProject\build\hci_ipc\b0n\zephyr\.config the CONFIG_PCD_READ_NETCORE_APP_VERSION is commented out.

The problem (hanging in the do while loop) still exists.

What to do next ?

Best regards,

Georg

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Thu, 22 Aug 2024 08:30:50 GMT

Hi,

there is no subdirectory "/b0n/zephyr" under the directory "/ncs/v2.6.1/zephyr/samples/bluetooth/hci_ipc" in the ncs sdk 2.6.1.

Best regards

Georg

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Amanda Hsieh — Wed, 21 Aug 2024 19:34:27 GMT

Add CONFIG_PCD_READ_NETCORE_APP_VERSION=y to nrf\samples\nrf5340\netboot\prj.conf and check whether `CONFIG_PCD_READ_NETCORE_APP_VERSION is set in hci_ipc/b0n/zephyr/.config

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Wed, 21 Aug 2024 08:09:11 GMT

Hi,

are there some new ideas concerning this problem ?

Best regards,

Georg

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Thu, 15 Aug 2024 13:59:25 GMT

Hi,

no, it doesn't work. The system doesn't boot and hangs still in the "do while" of the mcuboot.

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Amanda Hsieh — Thu, 15 Aug 2024 13:53:22 GMT

Sounds it works as expected now with your configs files. Right?

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Thu, 15 Aug 2024 11:41:54 GMT

Hi,

this is what I added to the config files to activate the downgrade protection in complete.

mcuboot.conf under child_image folder:

CONFIG_BOOT_VERSION_CMP_USE_BUILD_NUMBER=y

CONFIG_MCUBOOT_DOWNGRADE_PREVENTION=y

CONFIG_FW_INFO=y
CONFIG_PCD_APP=y
CONFIG_PCD_READ_NETCORE_APP_VERSION=y

hci_ipc.conf under child_image folder:

CONFIG_FW_INFO_FIRMWARE_VERSION=2

b0n.conf under child_image folder:

CONFIG_PCD_READ_NETCORE_APP_VERSION=y

prj.conf:

CONFIG_FW_INFO=y
CONFIG_PCD_APP=y
CONFIG_PCD_READ_NETCORE_APP_VERSION=y

Since my last mail, I added only the 3 config switches in the prj.conf file.

The application doesn't boot and the mcuboot hangs in the loop as described above.

Best regards,

Georg

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Amanda Hsieh — Wed, 14 Aug 2024 14:13:51 GMT

Did you add CONFIG_PCD_READ_NETCORE_APP_VERSION for b0n? This option must be enabled in APP, MCUboot, and b0n configuration (when b0n is not configured, than application hangs after reboot).

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Wed, 14 Aug 2024 11:14:54 GMT

Hi,

the program hangs in the "do while" loop of the function: network_core_pcd_cmdset in the file pcd.c

The command_status is PCD_STATUS_READ_VERSION

tatic int network_core_pcd_cmdset(uint32_t cmd, const void *src_addr, size_t len, bool wait)
{
	int err;
	enum pcd_status command_status;

	/* Ensure that the network core is turned off */
	nrf_reset_network_force_off(NRF_RESET, true);

	err = pcd_cmd_write(cmd, src_addr, len, PCD_NET_CORE_APP_OFFSET);
	if (err != 0) {
		LOG_INF("Error while writing PCD cmd: %d", err);
		return err;
	}

	enum pcd_status initial_command_status = pcd_fw_copy_status_get();

	nrf_reset_network_force_off(NRF_RESET, false);
	LOG_INF("Turned on network core");

	if (!wait) {
		return 0;
	}

	do {
		/* Wait for 1 second to avoid issue where network core
		 * is unable to write to shared RAM.
		 */
		k_busy_wait(1 * USEC_PER_SEC);

		command_status = pcd_fw_copy_status_get();
	} while (command_status == initial_command_status);

Best regards,

Georg

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Wed, 14 Aug 2024 10:53:22 GMT

Hi,

the problem with the error is solved.

After flashing the software with the additional config switches, our software doesn't boot any more

It seems that the software hangs in the bootoloader.

Rest regards,

Georg

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Wed, 14 Aug 2024 08:36:34 GMT

Hi Amanda,

thank you for your answer and sorry for my late reply.

Up to now I didn't a have file b0n.conf . So I created this file with only this entry.

CONFIG_PCD_READ_NETCORE_APP_VERSION=y

I tried your solution but get some errors during build.

-- west build: generating a build system
Loading Zephyr default modules (Zephyr base).
-- Application: C:/Projekte/BleCan_CAB11A
-- CMake version: 3.21.0
-- Found Python3: C:/ncs/toolchains/cf2149caf2/opt/bin/python.exe (found suitable version "3.9.13", minimum required is "3.8") found components: Interpreter
-- Cache files will be written to: C:/DevTools/ncs/v2.6.1/zephyr/.cache
-- Zephyr version: 3.5.99 (C:/DevTools/ncs/v2.6.1/zephyr)
CMake Error at C:/DevTools/ncs/v2.6.1/zephyr/cmake/modules/version.cmake:76 (math):
math cannot parse the expression: "(2 << 16) + ( << 8) + (0)": syntax
error, unexpected exp_SHIFTLEFT (16).
Call Stack (most recent call first):
C:/DevTools/ncs/v2.6.1/zephyr/cmake/modules/zephyr_default.cmake:129 (include)
C:/DevTools/ncs/v2.6.1/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:66 (include)
C:/DevTools/ncs/v2.6.1/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:92 (include_boilerplate)
CMakeLists.txt:14 (find_package)

CMake Error at C:/DevTools/ncs/v2.6.1/zephyr/cmake/modules/version.cmake:77 (math):
math cannot parse the expression: "(2 << 24) + ( << 16) + (0 << 8) +
(2408081002)": syntax error, unexpected exp_SHIFTLEFT (16).
Call Stack (most recent call first):
C:/DevTools/ncs/v2.6.1/zephyr/cmake/modules/zephyr_default.cmake:129 (include)
C:/DevTools/ncs/v2.6.1/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:66 (include)
C:/DevTools/ncs/v2.6.1/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:92 (include_boilerplate)
CMakeLists.txt:14 (find_package)

Best regards,

Georg

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Amanda Hsieh — Fri, 09 Aug 2024 13:03:00 GMT

Hi,

To enable the netcore downgrade protection use FW_INFO_FIRMWARE_VERSION and add the following kconfigs:

mcuboot.conf under child_image folder:

CONFIG_FW_INFO=y
CONFIG_PCD_APP=y
CONFIG_PCD_READ_NETCORE_APP_VERSION=y

hci_ipc.conf under child_image folder:

CONFIG_FW_INFO_FIRMWARE_VERSION=2

b0n.conf under child_image folder:
CONFIG_PCD_READ_NETCORE_APP_VERSION=y

-Amanda H.

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Amanda Hsieh — Thu, 08 Aug 2024 16:31:31 GMT

I will update if the team has anything.

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Thu, 08 Aug 2024 07:27:47 GMT

Hi,

thank you.

I hope you find a solution because we want to use this feature in our product.

Best regards,

Georg

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

responsible_duck — Thu, 08 Aug 2024 01:42:48 GMT

Hi just wanted to add that we just found the same issue so can confirm a reproducible offender.

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Amanda Hsieh — Wed, 07 Aug 2024 14:18:17 GMT

Hi,

Sorry, it's nRF Connect Device Manager.

Thanks for finding the root cause. I will report to the internal.

-Amanda H.

RE: Downgrade protection works only for the app_core -image-and not for the net-core -image

Georg — Wed, 07 Aug 2024 09:35:39 GMT

Hi Amanda,

thank you for your answer.

When looking in the google play store I can't find the nRF Device app.

There is a nRF Device Manager app but here I can't find the option to read out the version.

Which app do you mean?

To get different versions for the net-image I added a version string in the main program of the net-core-image like this:

After updating the device I read out the memory of the nrf5340 (with the Programmer) and check the version string like this:

What I found out during debugging is that the version of the net image get lost when MCUboot transfers the net-core-image from the secondary slot to the primary slot. The version information which is placed in the header of the net_core_app_update.bin image is not programmed into the net core (primary slot). MCUboot assumes that the version of the net-core-image is 0.0.0, this means that downgrade prevention doesn’t work.

See the function boot_read_image_header_hook_in the file nrf_hooks.c

int boot_read_image_header_hook_(int img_index, int slot, struct image_header *img_head)
{
	if (img_index == 1 && slot == 0) {
		img_head->ih_magic = IMAGE_MAGIC;
		img_head->ih_hdr_size = PM_MCUBOOT_PAD_SIZE;
		img_head->ih_load_addr = PM_MCUBOOT_PRIMARY_1_ADDRESS;
		img_head->ih_img_size = PM_CPUNET_APP_SIZE;
		img_head->ih_flags = 0;
		img_head->ih_ver.iv_major = 0;
		img_head->ih_ver.iv_minor = 0;
		img_head->ih_ver.iv_revision = 0;
		img_head->ih_ver.iv_build_num = 0;
		img_head->_pad1 = 0;
		return 0;
	}

	return BOOT_HOOK_REGULAR;
}

Best regards,

Georg