Password reset via u-boot (init=/bin/sh) possible?

[macmartin]

for anyone following I'm sharing what was written in the PN chat yesterday:
1.) an updated flashing instruction: https://codeberg.org/shom/gists/src/bran...lashing.md
2.) a way to correct stuff via uart console by hrdl:

[I] <hrdl>:
[...] whoever wants to fix their system via uart console: it's possible to translate ones extlinux.conf to something bootable via booti with a modified cmdline
I have an image, dtb, and an initrd in /boot/emergency/ , which I can boot. Those paths are easier to type and should be usable in case ls mmc 0:5 /boot/emergency lists those
Otherwise let's assume we use 6.12.11-pinenote-202501281646-00249-g211ba27556cc .
Here are the instructions for posterity:

1. Reboot, selection option 3 (u-boot menu, either via console, button presses, or the touch screen)
2. Check usable kernels. OS1 uses partition 5
  ls mmc 0:5 /boot
3. Load kernel, dtb, and initrd. Set cmdline and boot
  load mmc 0:5 $kernel_addr_r /boot/vmlinuz-6.12.11-pinenote-202501281646-00249-g211ba27556cc
  load mmc 0:5 $fdt_addr_r /usr/lib/linux-image-6.12.11-pinenote-202501281646-00249-g211ba27556cc/rockchip/rk3566-pinenote-v1.2.dtb
  load mmc 0:5 $ramdisk_addr_r /boot/initrd.img-6.12.11-pinenote-202501281646-00249-g211ba27556cc
  setenv bootargs root=/dev/mmcblk0p5 rw rootwait earlycon console=tty0 console=ttyS2,1500000n8 fw_devlink=off init=/bin/sh
  booti $kernel_addr_r $ramdisk_addr_r:$filesize $fdt_addr_r
4. Fix what needs fixing, e.g. usermod -aG sudo new_user, passwd root, sed -i s/mynewusername/user/ /etc/passwd && mv /home/mynewusername /home/user
5. Exit / C-d to reboot
Pasting doesn't seem to work well, at least not with my screen setup. I hope this helps