Debian | can't install linux-headers-6.12.12+bpo-amd64; function “strlcpy” is unknown

I'm a Debian 12 derivative and I'm trying to install Nvidia drivers. To do so, I needed to install linux-headers and dependencies: First, I've checked my kernel info, uname -r 6.12.12+bpo-amd64 After that, I've tried to install relative packages: sudo apt install linux-headers-6.12.12+bpo-amd64 And then, I've received the error messages, make -j16 KERNELRELEASE=6.12.12+bpo-amd64 KERNEL_DIR=/lib/modules/6.12.12+bpo-amd64/build all...(bad exit status: 2) Error! Bad return status for module build on kernel: 6.12.12+bpo-amd64 (x86_64) Consult /var/lib/dkms/v4l2loopback/0.12.7/build/make.log for more information. Error! One or more modules failed to install during autoinstall. Refer to previous errors for more information. dkms: autoinstall for kernel: 6.12.12+bpo-amd64 failed! run-parts: /etc/kernel/header_postinst.d/dkms exited with return code 11 Failed to process /etc/kernel/header_postinst.d at /var/lib/dpkg/info/linux-headers-6.12.12+bpo-amd64.postinst line 11. When I check the related logs, sudo cat /var/lib/dkms/v4l2loopback/0.12.7/build/make.log DKMS make.log for v4l2loopback-0.12.7 for kernel 6.12.12+bpo-amd64 (x86_64) Prş 03 Nis 2025 22:14:27 +03 Building v4l2-loopback driver... make -C /lib/modules/6.12.12+bpo-amd64/build M=/var/lib/dkms/v4l2loopback/0.12.7/build modules make: Entering directory '/usr/src/linux-headers-6.12.12+bpo-amd64' CC [M] /var/lib/dkms/v4l2loopback/0.12.7/build/v4l2loopback.o /var/lib/dkms/v4l2loopback/0.12.7/build/v4l2loopback.c: In function ‘vidioc_querycap’: /var/lib/dkms/v4l2loopback/0.12.7/build/v4l2loopback.c:717:9: error: implicit declaration of function ‘strlcpy’; did you mean ‘strncpy’? [-Werror=implicit-function-declaration] 717 | strlcpy(cap->driver, "v4l2 loopback", sizeof(cap->driver)); | ^~~~~~~ | strncpy cc1: some warnings being treated as errors make: *** [/usr/src/linux-headers-6.12.12+bpo-common/scripts/Makefile.build:234: /var/lib/dkms/v4l2loopback/0.12.7/build/v4l2loopback.o] Error 1 make: *** [/usr/src/linux-headers-6.12.12+bpo-common/Makefile:1962: /var/lib/dkms/v4l2loopback/0.12.7/build] Error 2 make: *** [/usr/src/linux-headers-6.12.12+bpo-common/Makefile:236: __sub-make] Error 2 make: Leaving directory '/usr/src/linux-headers-6.12.12+bpo-amd64' make: *** [Makefile:43: v4l2loopback.ko] Error 2 What could be the possible reason and what should I do for that? Best, Orkut