-check-requirements : kernel config not found

[BobSquarePants]

Describe the bug

$ opensnitchd -check-requirements
❌ kernel config not found (6.6.63-v8_TESTTT+) in any of the expected paths

Include the following information

• OpenSnitch version.
  1.6.6
• OS:
  Devuan GNU/Linux 5 (daedalus)
• Kernel version: echo $(uname -a)

Linux 6.6.63-v8_TESTTT+ #1 SMT PREEMPT aarch64 GNU/Linux

Additional context
I've build my own kernel in order to have the missing "modules"

Cross-compiled commands

su
apt install bc bison flex libssl-dev make libc6-dev libncurses5-dev crossbuild-essential-arm64

cd /tmp/LinuxKernel/linux

git clone --depth=1 --branch rpi-6.6.y https://github.com/raspberrypi/linux

cd linux
KERNEL=kernel8
make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- bcm2711_defconfig

make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- menuconfig

make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- Image modules dtbs
env PATH=$PATH make -j12 ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- INSTALL_MOD_PATH=/to/sd_boot modules_install

cp /tmp/LinuxKernel/linux/Image /to/sd_boot/$KERNEL.img
cp /tmp/LinuxKernel/linux/dts/broadcom/*.dtb /to/sd_boot/
cp /tmp/LinuxKernel/linux/dts/overlays/*.dtb* /to/sd_boot/overlays/
cp /tmp/LinuxKernel/linux/dts/overlays/README /to/sd_boot/overlays/
umount /to/sd_boot/
umount /to/sd_root/

[gustavo-iniguez-goya]

Compile the kernel with the option CONFIG_IKCONFIG , it'll generate the file /proc/config.gz once the syste mboot up (you may need also to load the module configs).

Also see if the config file is under any of these paths:

	"/proc/config.gz"
	"/boot/config-$(uname -r)"
	"/usr/src/linux-$(uname -r)/.config"
	"/usr/src/linux/.config"
	"/usr/lib/modules/$(uname -r)/config"
	"/usr/lib/ostree-boot/config-$(uname -r)"
	"/usr/lib/kernel/config-$(uname -r)"
	"/usr/src/linux-headers-$(uname -r)/.config"
	"/lib/modules/$(uname -r)/build/.config"

[BobSquarePants]

Thank you @gustavo-iniguez-goya

I had CONFIG_IKCONFIG set during compiling

CONFIG_IKCONFIG=m
CONFIG_IKCONFIG_PROC=y

but modprobe ikconfig return

FATAL: Module ikconfig not found in directory

I'll fix this and try to launch again opensnitchd -check-requirements

[BobSquarePants]

ok so I've fixed the ikconfig and could run
opensnitchd -check-requirements

here the two fail of it

Checking => CONFIG_KPROBES_ON_FTRACE=y
KPROBES not fully supported by this kernel.

Checking => CONFIG_HAVE_KPROBES_ON_FTRACE=y
KPROBES not fully supported by this kernel.

While building my kernel ( 6.6.63 ) https://github.com/raspberrypi/linux
I couldn't active those two trough menuconfig

I guess those two features are not available in that kernel version ?

So will opensnitch works without them ?

Thanks.

[gustavo-iniguez-goya]

Yes, it should work.

We discussed that flag here: #1145

CONFIG_KPROBES_ON_FTRACE flag is not set for arm:
https://github.com/torvalds/linux/blob/master/Documentation/features/debug/kprobes-on-ftrace/arch-support.txt

So we could check the architecture when checking for that flag.

[BobSquarePants]

Thank you @gustavo-iniguez-goya indeed it's the same topic ( I'll close this one in a few )

So we could check the architecture when checking for that flag.

If you point me the file that host the code of the -check-requirements https://github.com/evilsocket/opensnitch/blob/master/daemon/core/system.go ,

I'll look if I can do a commit for it :)
edit: humm it's in .go ¯\(ツ)/¯, first I'll improve my git skill then I'll look back to it, if I figure out, how to do it in .go