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Given that /system and a few other partitions are ext4 already, I know kernel support is built it. I'm guessing I'd need to root the device and edit the script that mounts/unmounts the microSD card. Anyone else know an easier way to do it? Apparently noone who manufactures tablets needs files over 4GB...Idiots.
I may give this a try today to see if I can figure out an easy way to do it. Although, I really need TrueCrypt support since most of my external drives are truecrypt containers. :-(
I suppose with root access it'd be a simple matter of mount -t ext4 /dev/block/whateversdcards /mnt/sdcard
I've still yet to root my device to test it though.
Did you ever give this a try?
It would be even cooler if we could convert the internal sdcard to ext4. It seems to be FAT32 as well. Then we could do a symlink under sdcard to the micro.
I want to be able to securely delete files(overwrite the whole file at least once) on my s3. I tried to install the app undelete which also has an option to securely delete files. But when I start the app it complains about not finding any fat formated file system. I also tried shredroid but this program crashes on startup, maybe because it also expects a fat file system? So is there a working way to secure delete files on the s3? It doesn't have to be an app, if there is some linux utility like srm compiled for android that would be great.
There's an app called Secure Deletion for Android in the Play Store that should do what you need. No free version, though, and it only has one review and 50+ downloads. FWIW, the single review was 5 stars. I'm gonna keep looking because I would like the same thing.
From what I can tell, stuff like that wont work on our devices' internal memory due to the method samsung has used to grant access to the partitions. Undelete never worked on my Xoom because of the same issue, possibly due to the fact both devices utilize MTP. However, it should work on any external SD cards you may have, however that is just me speculating as I have not tried it.
Sent from my SAMSUNG-SGH-I747 using xda premium
d3athsd00r said:
From what I can tell, stuff like that wont work on our devices' internal memory due to the method samsung has used to grant access to the partitions. Undelete never worked on my Xoom because of the same issue, possibly due to the fact both devices utilize MTP. However, it should work on any external SD cards you may have, however that is just me speculating as I have not tried it.
Sent from my SAMSUNG-SGH-I747 using xda premium
Click to expand...
Click to collapse
Now that you mention it, the internal storage is mounted as a FUSE filesystem, not the expected ext3/4, so it's probably because it's a "fake" filesystem. I wonder if there is a way to access the raw physical filesystem (/data is ext4, which should be compatible with most secure delete apps) instead of the userspace filesystem.
EndlessDissent said:
Now that you mention it, the internal storage is mounted as a FUSE filesystem, not the expected ext3/4, so it's probably because it's a "fake" filesystem. I wonder if there is a way to access the raw physical filesystem (/data is ext4, which should be compatible with most secure delete apps) instead of the userspace filesystem.
Click to expand...
Click to collapse
Thank you. Couldn't remember what it is called. But that is exactly the reason it can't find it with the app. Also, if journaling is enabled, then a secure delete still wont work on ext3/4. This isn't a bug, its due to the way ext with journaling handles reads/writes.
Sent from my SAMSUNG-SGH-I747 using xda premium
Anyone know why it's mounted via fuse? The same files are also available via /data/media and /data is mounted as ext4. Maybe it would be possible to unmount the fuse filesystem, remount the data filesystem as ext2 (no journaling) and then run some secure delete program?
octapod said:
Anyone know why it's mounted via fuse? The same files are also available via /data/media and /data is mounted as ext4. Maybe it would be possible to unmount the fuse filesystem, remount the data filesystem as ext2 (no journaling) and then run some secure delete program?
Click to expand...
Click to collapse
It's because of the MTP. If it were mounted as a normal filesystem, you could use USB Mass Storage, but you would lose access to all of your internal storage while it was in UMS mode.
Also, I don't think you can mount one filesystem as another, so mounting ext4 as ext2 will possibly corrupt your data. What you could do is mount the ext4 filesystem with the journal features turned off (which is practically the same as ext2 but better), then secure delete.
The issue for me is, that task seems a lot more involved on a phone/tablet than it is on an actual computer. Not sure if it would even work. And if you want to secure delete every time you delete something, that's a whole lot of effort to go through. Of course, if you want it deleted that badly, it's probably worth it to you.
Hi there!
I have myself a rooted Tilapia Nexus 7 with me, and I'm trying to watch videos off of an ext4 partition from my external hdd. To mount, I use Stickmount to mount the drive, ES File Explorer to browse the drive for the video I wanna watch, and MX Player to watch the video. It works when I watch videos from its FAT32 partition, but ES File Explorer reports that my ext4 partition is empty.
Since the automated way wouldn't work, I checked out the directory in the terminal emulator and found out it was empty. When that failed, I tried out mounting manually via terminal emulator. I used
Code:
mount
to figure out where the FAT32 partition was being mounted, then I tried manually mounting with:
Code:
# mount -t ext4 /dev/block/sda2 /data/media/0/usbStorage/sda2
This worked in the terminal, and
Code:
ls -a
listed the files in the ext4 partition, but ES File Explorer still wouldn't see the files. I then tried
Code:
# chmod -R 777 /data/media/0/usbStorage/sda2
# chown media_rw /data/media/0/usbStorage/sda2
You'll notice the 'chown' doesn't use '-R', and that's because the native 'chown' on android doesn't support it (surprisingly). I used 'chown' on the folder (sda2) and one folder inside it to see if the problem was ownership. Apparently it wasn't, cause they still didn't appear.
When this didn't work, I made an account here, and posted this question, so here I am.
So, any suggestions?
UPDATE 1:
I recently installed busybox to see if that'd fix it. I used the 'normal' install setting. Long story short, it didn't, and note I have a whole bunch of what I perceive to be useless symlinks, which I suspect over wrote the original binaries. Luckily, not all the binaries were overwritten as some don't work as they should; chown, for example, doesn't work with the android groups and users. I can't uninstall it cause apparently something goes wrong.
UPDATE 2:
StickMount still won't mount my ext4 partition correctly and ES File Explorer still won't detect my files, so I use a terminal, get superuser permissions with
Code:
su
, mount the partition with the above command, and use
Code:
cp
to copy the videos I wanna watch into the 'Movies' folder. It takes some time, and I worry about wearing out the internal storage's sectors, but I suppose it's less costly on the battery life.
Okay so i was just doing a bit of file management. I removed a 1.4gb psp iso i had on my nexus 7 and then i checked how much space i had left using storage option in settings. I checked it and it said i had 25gb free when before i removed my file i had only 13gb free. Tried rebooting device and then used es file explorer to see all files. Opened es file explorer and then noticed everything was gone. Only stock items were folders were left eg Android, Download etc. All my msuic and some game data was gone. Opened up asphalt 7 to see if it would still work but it doesnt anymore. Tried opening real racing 3 And it asks me to redownload game data. My widgets are still in homescreen and work and some of the other apps i have still work as well eg plague inc, subway surfer and most of the other ones.
Any idea on how this happened and how i can recover my files? I have a bugsense file as well that was left on my device.
As to recovery of lost files your options are not good. (And if we're talking a non-rooted device, the odds are approximately equal to 0%) Recovery in ext4 filesystems is technically much more challenging than in simple filesystems such as FAT. And this pessimistic outlook presumes that the filesystem is healthy/clean. If the reason for the problem occurring in the first place was a corrupted filesystem, then the odds go from simply bad to pathetically poor.
Sorry, dude... got any Nandroid or TiBu backups stored on your PC?
If you had Putin's top-secret files on your N7 and the CIA got hold of it, the first thing a forensic analyst would do is try to take a raw (block) device dump off of the "cold" device. (If you are still running the N7 with the regular OS the /data partition is being continually written to, and this further reduces the chances of file recovery every second the device is booted).
In the case of an analyst with less resources, this might mean using a custom recovery boot to get the raw device copy; unfortunately, the /data partition is huge - nearly 30 GB - so you would have to mount a extN filesystem via OTG... and doing so thus precludes using adb, so you would need to use a recovery with a touch interface and command-line entry (e.g. TWRP)
# mkdir /mnt/myOTGdisk
# mount -t ext2 -o rw /dev/sda1 /mnt/myOTGdisk/
# dd bs=8196 if=/dev/block/platform/sdhci-tegra.3/by-name/UDA of=/mnt/myOTGdisk/userdata.img
Doing such a thing would allow you to examine that huge image file with forensic file recovery tools from a PC (probably running Linux) as in principle you captured the entire ext4 filesystem.
The thing is, efforts spent in file recovery should be proportional to the value of the files being recovered. I'm not sure if your saved gaming history rises to that occasion. For sure the dude at the CIA won't want to help you with that.
As to the source of your troubles, it's hard to say. With TWRP booted, you can run the "e2fsck" program to see if the /data ext4 filesystem is corrupted, e.g.
# mount | grep /data ( see which mmcblk0 partition is /data, on grouper it is mmcblk0p9 )
# umount /sdcard
# umount /data
# e2fsck -f -n /dev/block/platform/sdhci-tegra.3/by-name/UDA
(For the last command above, you might need to use the block device name /dev/block/mmcblk0p?? instead of the UDA symlink )
If the above command shows that you have a corrupted /data filesystem, I would re-initialize that filesystem ( "fastboot format userdata" ) - note this wipes all userdata including the psuedo-SD card.
Finally, I should point out that some type of hardware failure might have occurred somewhere in that huge 30 GB partition - if that is the case then there will be problems down the road again. If that is the case, the only way to detect this will be a write test which nearly fills that partition, followed by a filesystem sanity check as shown above.
Probably that would need to be done in the recovery rather than in the normal OS, as a nearly full /data filesystem will probably wedge the device.
Phew, I've said enough.
Good luck
I never tire of reading your posts, bftb0, ("...the odds are approximately equal to 0%")...genius.
But don't the CIA have access to Cray, 'Kasparov' DeepBlue beating SuperComputers that could make mincemeat out of the kind of thing your alluding to... in less time than it takes to flash a ROM... or have I been watching too many James Bond movies?
Vaguely rhetorical question - think I already know the answer...
Still... what a great post.
Rgrds,
Ged.
---------- Post added at 01:22 AM ---------- Previous post was at 12:50 AM ----------
Hi, leont1280...
You could try running this ...
Disk Usage - http://play.google.com/store/apps/details?id=com.google.android.diskusage&hl=en
It gives a graphical 'map' or overview of your storage, and you can visually see where everything is (or should be), great for tracking down missing stuff... but as bftb0 has mentioned, it doesn't look promising.
Rgrds,
Ged.
Use astro file manager u can check it out
Sent from my Nexus 7 using Tapatalk 2
Right bftb0 i did what you said in twrp and i recieved the following summary information.
/dev/block/mmcblk0p10: 28133/1835008 files (3.2% non-contiguous) , 1571673/733977
Any idea on what that means?
Also under the mount option in Twrp i can Unmount and mount the System, Data and its Cache. However i cant Mount the SD Card. Should that be a concern?
bftb0 said:
As to recovery of lost files your options are not good. (And if we're talking a non-rooted device, the odds are approximately equal to 0%) Recovery in ext4 filesystems is technically much more challenging than in simple filesystems such as FAT. And this pessimistic outlook presumes that the filesystem is healthy/clean. If the reason for the problem occurring in the first place was a corrupted filesystem, then the odds go from simply bad to pathetically poor.
Sorry, dude... got any Nandroid or TiBu backups stored on your PC?
If you had Putin's top-secret files on your N7 and the CIA got hold of it, the first thing a forensic analyst would do is try to take a raw (block) device dump off of the "cold" device. (If you are still running the N7 with the regular OS the /data partition is being continually written to, and this further reduces the chances of file recovery every second the device is booted).
In the case of an analyst with less resources, this might mean using a custom recovery boot to get the raw device copy; unfortunately, the /data partition is huge - nearly 30 GB - so you would have to mount a extN filesystem via OTG... and doing so thus precludes using adb, so you would need to use a recovery with a touch interface and command-line entry (e.g. TWRP)
# mkdir /mnt/myOTGdisk
# mount -t ext2 -o rw /dev/sda1 /mnt/myOTGdisk/
# dd bs=8196 if=/dev/block/platform/sdhci-tegra.3/by-name/UDA of=/mnt/myOTGdisk/userdata.img
Doing such a thing would allow you to examine that huge image file with forensic file recovery tools from a PC (probably running Linux) as in principle you captured the entire ext4 filesystem.
The thing is, efforts spent in file recovery should be proportional to the value of the files being recovered. I'm not sure if your saved gaming history rises to that occasion. For sure the dude at the CIA won't want to help you with that.
As to the source of your troubles, it's hard to say. With TWRP booted, you can run the "e2fsck" program to see if the /data ext4 filesystem is corrupted, e.g.
# mount | grep /data ( see which mmcblk0 partition is /data, on grouper it is mmcblk0p9 )
# umount /sdcard
# umount /data
# e2fsck -f -n /dev/block/platform/sdhci-tegra.3/by-name/UDA
(For the last command above, you might need to use the block device name /dev/block/mmcblk0p?? instead of the UDA symlink )
If the above command shows that you have a corrupted /data filesystem, I would re-initialize that filesystem ( "fastboot format userdata" ) - note this wipes all userdata including the psuedo-SD card.
Finally, I should point out that some type of hardware failure might have occurred somewhere in that huge 30 GB partition - if that is the case then there will be problems down the road again. If that is the case, the only way to detect this will be a write test which nearly fills that partition, followed by a filesystem sanity check as shown above.
Probably that would need to be done in the recovery rather than in the normal OS, as a nearly full /data filesystem will probably wedge the device.
Phew, I've said enough.
Good luck
Click to expand...
Click to collapse
Right bftb0 i did what you said in twrp and i recieved the following summary information.
/dev/block/mmcblk0p10: 28133/1835008 files (3.2% non-contiguous) , 1571673/733977
Any idea on what that means?
Also under the mount option in Twrp i can Unmount and mount the System, Data and its Cache. However i cant Mount the SD Card. Should that be a concern?
leont1280 said:
Right bftb0 i did what you said in twrp and i recieved the following summary information.
/dev/block/mmcblk0p10: 28133/1835008 files (3.2% non-contiguous) , 1571673/733977
Click to expand...
Click to collapse
Hmmm, mmcblk0p10 - you must have a tilapia (3G N7) device, yes?
If you had any filesystem errors, that e2fsck run would have produced copious reams of output. If a filesystem is clean, it produces only 5 or 6 lines of summary output.
leont1280 said:
Any idea on what that means?
Also under the mount option in Twrp i can Unmount and mount the System, Data and its Cache. However i cant Mount the SD Card. Should that be a concern?
Click to expand...
Click to collapse
I've seen the same business with TWRP and the /sdcard mount - I wouldn't worry about it. (It is not a "normal" mount in the sense of extN or FAT device partition mount - it behaves sort of like a strange symlink where the target directory and descendants all appear to have different file ownership and permissions than what exist in the true (underlying) filesystem. No doubt this is all performed in the kernel... I don't know whether a command-line invocation of "mount" can create this mount point, or whether a specific syscall/ ioctl is needed)
But back to your N7 - the lack of any errors in the filesystem check is good news, but also suggests that your files didn't disappear through a hardware failure. Are you sure you didn't fat-finger things when using the file manager? (I suppose it is possible that the file manager has a bug...)
I didn't look into what tools are available for extN forensic/recovery work. I can guess that the effort would be non-trivial, though.
bftb0 said:
Hmmm, mmcblk0p10 - you must have a tilapia (3G N7) device, yes?
If you had any filesystem errors, that e2fsck run would have produced copious reams of output. If a filesystem is clean, it produces only 5 or 6 lines of summary output.
I've seen the same business with TWRP and the /sdcard mount - I wouldn't worry about it. (It is not a "normal" mount in the sense of extN or FAT device partition mount - it behaves sort of like a strange symlink where the target directory and descendants all appear to have different file ownership and permissions than what exist in the true (underlying) filesystem. No doubt this is all performed in the kernel... I don't know whether a command-line invocation of "mount" can create this mount point, or whether a specific syscall/ ioctl is needed)
But back to your N7 - the lack of any errors in the filesystem check is good news, but also suggests that your files didn't disappear through a hardware failure. Are you sure you didn't fat-finger things when using the file manager? (I suppose it is possible that the file manager has a bug...)
I didn't look into what tools are available for extN forensic/recovery work. I can guess that the effort would be non-trivial, though.
Click to expand...
Click to collapse
Im pretty sure i didnt accidently delete it myself. When i was doing file management i was using my laptop with the N7 3g connected to it via MTP. Once i deleted the iso file the N7 started acting strange. I did notice a bit of lag that was usually out lf the ordinary and when i checked available space left it increased to 25gb rather than saying 13gb
aaah, having the same problem here, i was cleaning my n7 using my laptop, found a strange folder on my sd card, looked inside and it has a back up of some of my deleted files! interesting! i deleted the folder, then i started cheking other folders, like my ebooks, audio books and etc, but all my folders were empty!
so i disconnected my tablet, and after reconnecting, bam, all files gone.
I've given up on reformatting the internal memory as EXT4 (my last post). However now, I want to mount an external SD card that is EXT4 (or any file format that has UNIX permissions). I can't get my device to mount the card, it says the filesystem is unsupported. Now, that's bull**** since Android has built in support for EXT. After searching threads here on XDA and Google, and even purchasing EzyMount as recommended, I can't get it to mount. I've tried BusyBox and mount commands (as root), with various errors such as "mount operation not supported on transport endpoint". I'm at my wit's end by now, trying to get some filesystem which has support for symlinks and UNIX permissions... any ideas?
kcattakcaz said:
I've given up on reformatting the internal memory as EXT4 (my last post). However now, I want to mount an external SD card that is EXT4 (or any file format that has UNIX permissions). I can't get my device to mount the card, it says the filesystem is unsupported. Now, that's bull**** since Android has built in support for EXT. After searching threads here on XDA and Google, and even purchasing EzyMount as recommended, I can't get it to mount. I've tried BusyBox and mount commands (as root), with various errors such as "mount operation not supported on transport endpoint". I'm at my wit's end by now, trying to get some filesystem which has support for symlinks and UNIX permissions... any ideas?
Click to expand...
Click to collapse
you fully rooted with custom kernel or only with rdlv etc?
First you gotta figure out how to mount this damn thing, gotta be possible.
Then you need to get this done on bootup, either in init.rc or init.d or smth.
You probably just use wrong commands? But I could be wrong, didnt try that yet but would also be interested. Having the file permissions also on SD would be nice, but it could cause trouble with mtp maybe?
zroice said:
you fully rooted with custom kernel or only with rdlv etc?
First you gotta figure out how to mount this damn thing, gotta be possible.
Then you need to get this done on bootup, either in init.rc or init.d or smth.
You probably just use wrong commands? But I could be wrong, didnt try that yet but would also be interested. Having the file permissions also on SD would be nice, but it could cause trouble with mtp maybe?
Click to expand...
Click to collapse
I am rooted, but stock ROM and kernel. MTP is for connecting to a computer? If it is, I don't need that. I have tried
mount -rw -t ext4 /dev/block/mmcblk1p1 /storage/extStorageCard
and variants switching the flags and options.
Interesting... I just typed that command in to make sure I didn't make any typos.... and my phone crashed and rebooted. I typed it again to see if it would cause another crash and it appears to have mounted the card! Whwn I type "df" at the prompt it now shows a 28.6 GB filesystem at that location, which has to be my sd card.
Why, how, I don't know. It works, it's all I can say.