[HTC U12+ ROMs, Kernels, Recoveries, & Other Develo] mioni:
Hi [MENTION=3428502]Freak07[/MENTION], would you give me a hand plz~~~

After I restore my device via RUU, then OTA, patched the boot.img with magisk (fully followed you guide thread), I hoped to obtain the untouched system.img and I did follow steps in my Terminal:

sudo su

Password:

sh-3.2# HTC/adb shell

htc_imedugl:/ $ dd if=/dev/block/bootdevice/by-name/system$(getprop ro.boot.slot_suffix) of=/sdcard/system.img

dd: /dev/block/bootdevice/by-name/system_b: Permission denied

htc_imedugl:/ $ ls -l

ls: ./init.rc: Permission denied

ls: ./verity_key: Permission denied

ls: ./ueventd.rc: Permission denied

ls: ./ueventd.htc_ime.rc: Permission denied

ls: ./postinstall: Permission denied

ls: ./init.zygote64_32.rc: Permission denied

ls: ./init.zygote32.rc: Permission denied

ls: ./init.usb.rc: Permission denied

ls: ./init.usb.configfs.rc: Permission denied

ls: ./init.recovery.qcom.rc: Permission denied

ls: ./init.recovery.htc_ime.rc: Permission denied

ls: ./init.recovery.common.rc: Permission denied

ls: ./init.htc.storage.exfat.rc: Permission denied

ls: ./init.hosd_fusion.usb.rc: Permission denied

ls: ./init.hosd.usb.rc: Permission denied

ls: ./init.hosd.usb.configfs.rc: Permission denied

ls: ./init.hosd.nanohub.rc: Permission denied

ls: ./init.hosd.htc_ime.rc: Permission denied

ls: ./init.hosd.ftm_ime.rc: Permission denied

ls: ./init.environ.rc: Permission denied

ls: ./init.edge.rc: Permission denied

ls: ./init: Permission denied

total 3376

dr-xr-xr-x 109 root root 0 1970-03-18 21:17 acct

dr-xr-x--- 3 bluetooth net_bt 16384 1970-01-01 08:00 bt_firmware

lrwxrwxrwx 1 root root 50 1970-03-18 21:17 bugreports -> /data/user_de/0/com.android.shell/files/bugreports

lrwxrwxrwx 1 root root 11 1970-03-18 21:17 cache -> /data/cache

lrwxrwxrwx 1 root root 16 1970-03-18 21:17 carrier -> /persist/carrier

lrwxrwxrwx 1 root root 13 1970-03-18 21:17 charger -> /sbin/charger

drwxr-xr-x 4 root root 0 1970-01-01 08:00 config

lrwxrwxrwx 1 root root 13 1970-03-18 21:17 cota -> /persist/cota

lrwxrwxrwx 1 root root 17 1970-03-18 21:17 d -> /sys/kernel/debug

drwxrwx--x 46 system system 4096 2018-10-11 00:10 data

lrwxrwxrwx 1 root root 23 1970-03-18 21:17 default.prop -> system/etc/prop.default

drwxr-xr-x 16 root root 5080 2018-10-11 01:15 dev

lrwxrwxrwx 1 root root 15 1970-03-18 21:17 devlog -> /persist/devlog

drwxr-xr-x 6 root root 4096 1970-01-01 08:00 dsp

lrwxrwxrwx 1 root root 11 1970-03-18 21:17 etc -> /system/etc

lrwxrwxrwx 1 root root 20 1970-03-18 21:17 fataldevlog -> /persist/fataldevlog

dr-xr-x--- 3 system system 16384 1970-01-01 08:00 firmware

drwx------ 2 root root 0 1970-03-18 21:17 lost+found

drwxr-xr-x 10 root system 240 1970-03-18 21:17 mnt

drwxr-xr-x 2 root root 0 1970-03-18 21:17 oem

drwxrwx--x 24 root system 4096 2018-10-07 23:26 persist

drwxr-xr-x 743 root root 0 1970-01-01 08:00 proc

drwxr-xr-x 3 root root 0 1970-03-18 21:17 res

drwxr-x--- 2 root shell 0 2018-10-11 00:30 root

drwxr-xr-x 3 root root 360 2018-10-11 00:30 sbin

lrwxrwxrwx 1 root root 21 1970-03-18 21:17 sdcard -> /storage/self/primary

lrwxrwxrwx 1 root root 15 1970-03-18 21:17 sdcard2 -> /storage/ext_sd

-rw-r--r-- 1 root root 3390678 1970-03-18 21:17 sepolicy

drwxr-xr-x 5 root root 120 2018-10-11 00:30 storage

drwxr-xr-x 18 root root 0 1970-03-18 21:17 sys

drwxr-xr-x 18 root root 4096 2018-09-29 00:38 system

drwxr-xr-x 22 root root 4096 1970-01-01 08:00 system_root

lrwxrwxrwx 1 root root 16 1970-03-18 21:17 tombstones -> /data/tombstones

drwxr-xr-x 16 root root 4096 1970-01-01 08:00 vendor

htc_imedugl:/ $ dd if=/dev/block/bootdevice/by-name/system$(getprop ro.boot.slot_suffix) of=/sdcard/system.img

dd: /dev/block/bootdevice/by-name/system_b: Permission denied

how can I solve this "Permission denied" problem?

waiting for your reply~~thx