Userland: How to access sdcard?

[lapsio]

I'm trying to find a way to access sd card but I'm getting Permission Denied everywhere. Even with fake root. /data is inaccessible, there's no /sdcard and most of directories in /mnt return Permission Denied as well.

I gave UserLAnd permission to Storage on Android permissions level. Tried reinstalling multiple times. Didn't help.

[lapsio]

also where are stored UserLAnd files in Android storage? Are they still located in some "public" location like sdcard or somewhere in system files, inaccessible by Android file browsers?

[thedward]

Android's /sdcard appears to be mounted at /host-rootfs/sdcard/.

[lapsio]

Could you add some symlink somewhere? Because listing /host-rootfs itself gives Permission denied so it's a bit hard to guess what's inside and that you can jump over it to /host-rootfs/sdcard/

[corbinlc]

We can add a binding

[corbinlc]

We had this on gnuroot debian and will do it here too. The path for the sdcard is not always the same, so the binding will not always be /sdcard -> /host-rootfs/sdcard

A proot binding is conceptually similar to a symbolic link, but different.

[AdamMatthewLTM]

@lapsio ,

Thank you for your report and request. I have organized this reply into two parts, the first being related to permissions and the second being related to UserLAnd file locations.

Part 1:
Even as root, some directories in Android will return a 'permission denied' error if you attempt to perform certain tasks within them. For example, I can confirm that in the "data" folder the ls command will return a permission denied error. This is actually intended behavior in Android. However, you may be able to perform the same command within certain sub-directories.

"ls /data/data/tech.ula" should not return an error. If you can confirm this works for you @lapsio , please reply to this thread.

In regards to sdcard permissions , Android implements a different method of accessing it. As @thedward stated, the directory /host-rootfs/sdcard is the correct method to access that location. Furthermore, I do not believe any subdirectories within /host-rootfs should be met with permissions errors if you are accessing it as root.

Part 2:
UserLAnd undergoes a somewhat complex installation procedure, and the short version (from my limited understanding - if this is incorrect please correct this statement) is that the majority of installation files for debian will be found in the /data folder and subfolders for Android.

Any downloaded files will be stored in the Android download manager default location (folder "Downloads" for Android 7.0).

Thank you for filing this issue,
-Adam

[lapsio]

Yeah i know proot will give Permission Denied in lots of cases because it's fake root so it's not an issue. Issue is that there are _some_ files _somewhere_ which are accessible after going through "denied wall of obscurity". I think listing them in documentation or some README file in default user's home would be sufficient solution if they're not that much predictable. Well I just added ln -s /host-rootfs/sdcard / and it's fine but I wouldn't guess it without help. Here are my permissions after sudo su:

root@localhost:/home/lapsio# ls /data                                                  
ls: cannot open directory '/data': Permission denied                                   
root@localhost:/home/lapsio# ls /data/                                                 
ls: cannot open directory '/data/': Permission denied                                  
root@localhost:/home/lapsio# ls /data/data                                             
ls: cannot open directory '/data/data': Permission denied                              
root@localhost:/home/lapsio# ls /data/data/                                            
ls: cannot open directory '/data/data/': Permission denied                             
root@localhost:/home/lapsio# ls /data/data/tech.ula                                    
cache  code_cache  databases  files  shared_prefs                                      
root@localhost:/home/lapsio# ls /host-rootfs                                           
ls: cannot open directory '/host-rootfs': Permission denied                            
root@localhost:/home/lapsio# ls /host-rootfs/                                          
ls: cannot open directory '/host-rootfs/': Permission denied                           
root@localhost:/home/lapsio# ls /host-rootfs/sdcard                                    
ASUS                    Music               Downloads.... etc                                
root@localhost:/home/lapsio#

[lapsio]

This is another thing that worries me a bit but I don't know if it's okay:

lapsio@localhost ~> ls /mnt/                                                           
ls: cannot access '/mnt/media_rw': Permission denied                                   
appfuse/  asec/  expand/  media_rw/  obb/  runtime/  sdcard@  secure/  user/           
lapsio@localhost ~> file /mnt/sdcard                                                   
/mnt/sdcard: broken symbolic link to /storage/self/primary                             
lapsio@localhost ~>

I mean broken symbolic links is not really something you expect on fresh system i guess... Besides, for now this version seems to have superior compatibility comparing to old one in terms of files permissions handling. I compiled and installed without any issues some programs that required manual install scripts modification under old GNURoot in order to not crash in the middle.

[Root-voidX]

So i would like to add, I can definitely ls /host-rootfs and most of the other sub directories here except for /host-rootfs/data. And yes I can ls /host-rootfs/mnt. I assume at least for my device (S9+) that root directory is in /host-rootfs.

[corbinlc]

This should be fixed with release 0.2.3. #139
You can get to the sdcard via /sdcard from within the running session.
Please file separate issues for anything new.

[enang90]

/host-rootfs/sdcard

it's work tank's

[0W1audio]

Hello all,

I have two Android phones
One is running Android 6.0 and can access the SDCard from within UserLand Debian in root mode with ln -s /host-rootfs/sdcard /

The second one is running Android 8.1.0 and CANNOT access the SDCard from within UserLand Debian in root mode. The same command ln -s /host-rootfs/sdcard / return premission denied

I also tried under root permission (sudo su) to change the repertory rights with chmod -R 777 /host-rootfs and I got :
chmod : changing permissions of '/host-rootfs': Read-only file system
chmod : cannot read directory '/host-rootfs': Permission denied

While the same command work on Android 6.0

Please help as my Android phone 6.0 has issues and I would like to use my new phone.
Best regards,
Jean

[Dirk-LG]

Hi,

I also have this issue on a LG G7 running Android v9, not rooted, although I allow storage access to UserLand v2.6.3. In the previous version of UserLand I was able to access at least the _internal storage_ at mount point /sdcard (even I'd like to access the real SD card, too). How could I exchange data between Android and UserLand, else?

When I call "sudo mount" I get 11 mounts of "type sdcardfs" and "type vfat" listed which are all not working, examples:
/mnt/media_rw/F3B9-110D on /storage/F3B9-110D type sdcardfs
/mnt/media_rw/F3B9-110D on /mnt/runtime/write/F3B9-110D type sdcardfs
/data/media on /storage/emulated type sdcardfs
/dev/block/vold/public:179,1 on /mnt/media_rw/F3B9-110D type vfat
/dev/block/bootdevice/by-name/modem_b on /vendor/firmware_mnt type vfat
Even for sudo it does not work, and also "sudo ls -l /host-rootfs/" returns
/bin/ls: cannot open directory '/host-rootfs/': Permission denied

Please fix (or at least allow the previous access to the internal storage).

Thanks
Dirk

[Dirk-LG]

I read the information about scoped access at link https://github.com/CypherpunkArmory/UserLAnd/wiki/Importing-and-exporting-files-in-UserLAnd now. But what if I like to promote UserLAnd to be able to access all files and folders again? Think about a file explorer, how would such an app work in future?

Kind regards
Dirk

[prohacker167]

Could you add some symlink somewhere? Because listing /host-rootfs itself gives Permission denied so it's a bit hard to guess what's inside and that you can jump over it to /host-rootfs/sdcard/
/host-rootfs would show permission denied as it cant open root folders but /host-rootfs/sdcard/ will open.(It works for me)

[Yisus7u7]

Funcióno, gracias, son los mejores!!!