Error message in deleting IO80211Family.kext

Question

I would like to delete IO80211Family.kext from my Mac so as to disable wireless internet. However when I run the following command from the terminal, I get an error message:

sudo rm -rf /System/Library/Extensions/IO80211Family.kext

The error message is:

rm: /System/Library/Extensions/IO80211Family.kext: Operation not permitted

Answer 1

this is dependent on which operating system you are running. In catalina, you could still mount the root volume read/write

transfer115502:~ root# mount -vw /
transfer115502:~ root# mv /System/Library/Extensions/IO80211Family* /var/root/DISABLED_EXTENSIONS/System/Library/Extensions
mv: /System/Library/Extensions/IO80211Family.kext: unable to copy extended attributes to /var/root/DISABLED_EXTENSIONS/System/Library/Extensions/IO80211Family.kext: Operation not permitted
mv: /System/Library/Extensions/IO80211FamilyV2.kext: unable to copy extended attributes to /var/root/DISABLED_EXTENSIONS/System/Library/Extensions/IO80211FamilyV2.kext: Operation not permitted
transfer115502:~ root# ls -al /var/root/DISABLED_EXTENSIONS/System/Library/Extensions  
total 0
drwxr-xr-x  4 root  wheel  128 Jan 27 12:05 .
drwxr-xr-x  3 root  wheel   96 Jan 24 13:17 ..
drwxr-xr-x  3 root  wheel   96 Nov 20 20:29 IO80211Family.kext
drwxr-xr-x  3 root  wheel   96 Nov 20 20:05 IO80211FamilyV2.kext
transfer115502:~ root# ls -al /System/Library/Extensions | grep 80211
transfer115502:~ root#

I have not resolved how to do this in Monterey yet. first you must mount the root volume read/write

grant@transfer115503:~[20220502-10:56][#3]% df | head
Filesystem     512-blocks     Used Available Capacity iused      ifree %iused  Mounted on
/dev/disk1s1s1  489620264 29662464 419490472     7%  500637 2097452360    0%   /
devfs                 380      380         0   100%     659          0  100%   /dev
/dev/disk1s5    489620264       40 419490472     1%       0 2097452360    0%   /System/Volumes/VM
/dev/disk1s3    489620264   527656 419490472     1%     814 2097452360    0%   /System/Volumes/Preboot
/dev/disk1s6    489620264     1504 419490472     1%      22 2097452360    0%   /System/Volumes/Update
/dev/disk1s2    489620264 37498768 419490472     9%  304083 2097452360    0%   /System/Volumes/Data
map auto_home           0        0         0   100%       0          0  100%   /System/Volumes/Data/home
map auto_nfs            0        0         0   100%       0          0  100%   /System/Volumes/Data/mnt/san201
map auto_nfs            0        0         0   100%       0          0  100%   /System/Volumes/Data/mnt/san202
grant@transfer115503:~[20220502-11:07][#4]% diskutil mountDisk /dev/disk1s1
Volume(s) mounted successfully
grant@transfer115503:~[20220502-11:08][#5]% mount | grep disk1s1
/dev/disk1s1s1 on / (apfs, sealed, local, read-only, journaled)
/dev/disk1s1 on /Volumes/Macintosh HD 1 (apfs, sealed, local, journaled, nobrowse)
grant@transfer115503:~[20220502-11:09][#6]% cd /Volumes/Macintosh\ HD\ 1
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:09][#7]% sudo ln -s /System/Volumes/Data/mnt mnt
Password:
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:10][#8]% ls -1  /Volumes/Macintosh\ HD\ 1/System/Library/Extensions | grep 80211
IO80211Family.kext
IO80211FamilyLegacy.kext
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:11][#9]% sudo rm -rf /Volumes/Macintosh\ HD\ 1/System/Library/Extensions/IO80211Family.kext
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:11][#10]% sudo rm -rf /Volumes/Macintosh\ HD\ 1/System/Library/Extensions/IO80211FamilyLegacy.kext
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:11][#11]% sudo rm -rf /Volumes/Macintosh\ HD\ 1/System/Library/LaunchAgents/com.apple.wifi.WiFiAgent.plist 
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:13][#12]% sudo rm -rf /Volumes/Macintosh\ HD\ 1/System/Library/Extensions/AppleBluetooth*
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:13][#13]% sudo rm -rf /Volumes/Macintosh\ HD\ 1/System/Library/Extensions/AppleMIDIBluetoothDriver.plugin
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:14][#14]% sudo rm -rf /Volumes/Macintosh\ HD\ 1/System/Library/Extensions/IOBluetooth*
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:14][#15]% ls -1 /Volumes/Macintosh\ HD\ 1/System/Library/Extensions | grep 80211
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:14][#16]%

then create a new snapshot and and commit the tag

grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:14][#16]% now
202205021115
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:15][#17]% sudo /System/Library/Filesystems/apfs.fs/Contents/Resources/apfs_systemsnapshot -s "202205021115" -v /Volumes/Macintosh\ HD\ 1
Attempting creation of snapshot 202205021115 on volume: /Volumes/Macintosh HD 1 
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:17][#18]% sudo /System/Library/Filesystems/apfs.fs/Contents/Resources/apfs_systemsnapshot -r "202205021115" -v /Volumes/Macintosh\ HD\ 1
Attempting tagging of snapshot 202205021115 on volume: /Volumes/Macintosh HD 1 
grant@transfer115503:/Volumes/Macintosh HD 1[20220502-11:18][#19]% sudo reboot
Connection to transfer115503 closed by remote host.
Connection to transfer115503 closed.
grant@grants-EFILM-MacBookPro-M1:~[20220502-11:21][#326584]%

Even though the extensions were removed, after reboot the 80211 extension is loading from somewhere.

grant@transfer115503:~[20220502-11:25][#1]% cd /mnt/
grant@transfer115503:/mnt[20220502-11:25][#2]% ls
san201 san202 san203 san204 san205 san206 san207 san209 san210 san211
grant@transfer115503:/mnt[20220502-11:25][#3]% kextstat | grep 80211 | sed -E "s/[[:space:]]+/ /g" | cut -d " " -f 7
Executing: /usr/bin/kmutil showloaded
No variant specified, falling back to release
com.apple.iokit.IO80211Family
grant@transfer115503:/mnt[20220502-11:26][#4]%

My trip to Monterey is a longer drive than I had anticipated.