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No Wifi Adapter found in Ubuntu 20.04 LTS after chmod 777 to /usr and using recovery mode

cn flag
NAM

After change permission of "/usr" folder to 777, I got an error which is relevant to "sudo" permission and fixed that by using recovery mode. Everything seem be ok but I got another problem is my laptop cannot connect to wifi. In setting it show "No Wifi Adapter found". I try to follow some instructions I found and nothing changed. This is output of some commands that I think it can be useful for diagnosis:

namle5@1-namle5-u:~$ lshw -C network
    WARNING: you should run this program as super-user.
      *-network DISABLED        
           description: Wireless interface
           product: Comet Lake PCH-LP CNVi WiFi
           vendor: Intel Corporation
           physical id: 14.3
           bus info: pci@0000:00:14.3
           logical name: wlp0s20f3
           version: 00
           serial: 6c:6a:77:71:08:63
           width: 64 bits
           clock: 33MHz
           capabilities: bus_master cap_list ethernet physical wireless
           configuration: broadcast=yes driver=iwlwifi driverversion=5.15.0-58-generic firmware=66.f1c864e0.0 QuZ-a0-hr-b0-66.u latency=0 link=no multicast=yes wireless=IEEE 802.11
           resources: irq:16 memory:f1210000-f1213fff

namle5@1-namle5-u:~$ ethtool -i wlan0 | grep driver
Cannot get driver information: No such device

namle5@1-namle5-u:~$ ifconfig wlan0 up
wlan0: ERROR while getting interface flags: No such device

namle5@1-namle5-u:~$ rfkill list
1: phy0: Wireless LAN
    Soft blocked: no
    Hard blocked: no
2: hci0: Bluetooth
    Soft blocked: yes
    Hard blocked: no

namle5@1-namle5-u:~$ lspci | egrep -i 'intel'
00:00.0 Host bridge: Intel Corporation Comet Lake-U v1 4c Host Bridge/DRAM Controller (rev 0c)
00:02.0 VGA compatible controller: Intel Corporation CometLake-U GT2 [UHD Graphics] (rev 02)
00:04.0 Signal processing controller: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Thermal Subsystem (rev 0c)
00:12.0 Signal processing controller: Intel Corporation Comet Lake Thermal Subsytem
00:14.0 USB controller: Intel Corporation Comet Lake PCH-LP USB 3.1 xHCI Host Controller
00:14.2 RAM memory: Intel Corporation Comet Lake PCH-LP Shared SRAM
00:14.3 Network controller: Intel Corporation Comet Lake PCH-LP CNVi WiFi
00:14.5 SD Host controller: Intel Corporation Comet Lake PCH-LP SCS3
00:15.0 Serial bus controller: Intel Corporation Serial IO I2C Host Controller
00:16.0 Communication controller: Intel Corporation Comet Lake Management Engine Interface
00:17.0 SATA controller: Intel Corporation Comet Lake SATA AHCI Controller
00:1d.0 PCI bridge: Intel Corporation Comet Lake PCI Express Root Port #9 (rev f0)
00:1d.4 PCI bridge: Intel Corporation Comet Lake PCI Express Root Port #13 (rev f0)
00:1f.0 ISA bridge: Intel Corporation Comet Lake PCH-LP LPC Premium Controller/eSPI Controller
00:1f.3 Multimedia audio controller: Intel Corporation Comet Lake PCH-LP cAVS
00:1f.4 SMBus: Intel Corporation Comet Lake PCH-LP SMBus Host Controller
00:1f.5 Serial bus controller: Intel Corporation Comet Lake SPI (flash) Controller

namle5@1-namle5-u:~$ lspci -vv -s 00:14.3
00:14.3 Network controller: Intel Corporation Comet Lake PCH-LP CNVi WiFi
    Subsystem: Intel Corporation Wi-Fi 6 AX201 160MHz
    Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
    Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
    Latency: 0
    Interrupt: pin A routed to IRQ 16
    Region 0: Memory at f1210000 (64-bit, non-prefetchable) [size=16K]
    Capabilities: <access denied>
    Kernel driver in use: iwlwifi
    Kernel modules: iwlwifi, wl

namle5@1-namle5-u:~$ lspci -knn | grep Net -A3; rfkill list
00:14.3 Network controller [0280]: Intel Corporation Comet Lake PCH-LP CNVi WiFi [8086:02f0]
    Subsystem: Intel Corporation Wi-Fi 6 AX201 160MHz [8086:0074]
    Kernel driver in use: iwlwifi
    Kernel modules: iwlwifi, wl
1: phy0: Wireless LAN
    Soft blocked: no
    Hard blocked: no
2: hci0: Bluetooth
    Soft blocked: yes
    Hard blocked: no

Thanks for your helps

David avatar
cn flag
You make no mention of resetting the folder permissions to what they should be.
NAM avatar
cn flag
NAM
sorry I dont get what you mean, can you give me more details, please
guiverc avatar
cn flag
Many programs/tools won't function if the file permissions are not correct (eg. result of your `chmod 777`), so have you restored permissions back to their defaults (*you can expect operation to return to normal after you've done this*) ; ie. undone the damage you did with `chmod 777`?
David avatar
cn flag
It is a clear as it can be put the permissions you changed back.
pl flag
You may need to fix permissions or reinstall. Here's a similar question/answer on the Unix StackExchange. https://unix.stackexchange.com/a/13031/1610
NAM avatar
cn flag
NAM
Thank for your helps, seem reinstalling is appropiate solution in my case
guiverc avatar
cn flag
ps: You can re-install Ubuntu Desktop systems non-destructively (*which is useful to fix issues like this*), just use "*Something else*" and select your existing partition(s) ensuring you don't format them.. the lack of format causes the repair installation to occur.
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