Сброс пароля root пользователя admin на WB7

WB 7.2, релиз 2207:

U-Boot SPL 2021.10-wb1.1.1-g4c04347f3e (Feb 03 2022 - 14:48:16 +0000)
DRAM: 1024 MiB
Trying to boot from MMC2


U-Boot 2021.10-wb1.1.1-g4c04347f3e (Feb 03 2022 - 14:48:16 +0000)

CPU:   Allwinner R40 (SUN8I 1701)
Model: Wiren Board rev. 7.2.0 (A40i)
I2C:   ready
DRAM:  1 GiB
MMC:   mmc@1c0f000: 0, mmc@1c11000: 1
Loading Environment from MMC... OK
In:    serial@1c28000
Out:   serial@1c28000
Err:   serial@1c28000
Will only keep env vars: mmcpart bootcount upgrade_available uenvcmd otp_program otp_aes_program 
## Info: input data size = 43 = 0x2B
bootcount=0
mmcpart=2
upgrade_available=0

Environment size: 43/131068 bytes                                                                                                  
## Resetting to default environment                                                                                                
## Info: input data size = 43 = 0x2B                                                                                               
Net:   No ethernet found.                                                                                                          
Hit any key to stop autoboot:  0                                                                                                   
=> setenv optargs ro rootwait fixrtc single init=/bin/sh                                                                           
=> run bootcmd                                                                                                                     
switch to partitions #0, OK                                                                                                        
mmc1(part 0) is current device                                                                                                     
eMMC found on device 1                                                                                                             
Press FW button to enter firmware update mode                                                                                      
................................................                                                                                   
327 bytes read in 3 ms (106.4 KiB/s)                                                                                               
Importing environment from 0x42000000...                                                                                           
Checking if uenvcmd is set ...                                                                                                     
Running default loadzimage ...                                                                                                     
6035512 bytes read in 165 ms (34.9 MiB/s)                                                                                          
                                                                                                                                   
MMC read: dev # 1, block # 2016, count 32 ... 32 blocks read: OK                                                                   
Reading overlays list from eMMC                                                                                                    
Reading factory fdt name from eMMC                                                                                                 
Loading factory fdt sun8i-r40-wirenboard720                                                                                        
55196 bytes read in 7 ms (7.5 MiB/s)                                                                                               
254 bytes read in 2 ms (124 KiB/s)                                                                                                 
Applying DT overlay temp-industrial                                                                                                
Applying extra overlay                                                                                                             
Booting from mmc ...                                                                                                               
Kernel image @ 0x42000000 [ 0x000000 - 0x5c1838 ]                                                                                  
## Flattened Device Tree blob at 43000000                                                                                          
   Booting using the fdt blob at 0x43000000                                                                                        
   Loading Device Tree to 49fdd000, end 49ffffff ... OK                                                                            
                                                                                                                                   
Starting kernel ...   

(Удалил)                                                                                                             
             
[    4.592185]  mmcblk1: p1                                                                                                        
[    4.874004] EXT4-fs (mmcblk0p2): recovery complete                                                                              
[    4.880864] EXT4-fs (mmcblk0p2): mounted filesystem with ordered data mode. Opts: (null)                                        
[    4.889077] VFS: Mounted root (ext4 filesystem) readonly on device 179:2.                                                       
[    4.896730] devtmpfs: mounted                                                                                                   
[    4.905143] Freeing unused kernel memory: 1024K                                                                                 
[    4.909944] Run /bin/sh as init process                                                                                         
/bin/sh: 0: can't access tty; job control turned off                                                                               
# [   35.049145] vcc-gmac-phy: disabling                                                                                           
[   35.053003] dc5ldo: disabling                                                                                                   
[   35.056320] dldo4: disabling                                                                                                    
                                                                                                                                   
# mount                                                                                                                            
mount: failed to read mtab: No such file or directory                                                                              
# mount -n -o remount,rw /dev/mmcblk0p2 /                                                                                          
[  137.622188] EXT4-fs (mmcblk0p2): re-mounted. Opts: (null)                                                                       
# mount /dev/mmcblk0p6 /mnt/data                                                                                                   
[  147.882914] EXT4-fs (mmcblk0p6): recovery complete                                                                              
[  147.888794] EXT4-fs (mmcblk0p6): mounted filesystem with ordered data mode. Opts: (null)                                        
# 
          

То есть успешно проходит. Копируете точно строку без пробелов и символов?

Обратите внимание на строчку:

[    4.909944] Run /bin/sh as init process  

То есть ядру передан init из optargs