Re: USB flash drive opens read only -- how to fix?
On Thu, Oct 03, 2019 at 07:30:19AM +0200, Pascal Hambourg wrote: [...] > On the contrary. The usb-storage module has a parameter "quirks" > which allows to ignore the write-protect flag for a specific vid:pid > device (I do not remember the exact syntax). I was afraid that it > could be used to by-pass the write-protect switch so I tested it > with my only flash drive with a write-protect switch on. Although > the kernel considered the drive as writable, any write attempt > resulted to an error. Ah, that's interesting... now one could imagine a bug in the flash drive "OS", where it says "no, you can't write me" but accepts and performs write commands... > It is my understanding that Tomas meant that the write-protect > switch does not cut the transmission of the electrical write signal > to the flash memory chips and that the USB mass storage protocol > also includes rejecting write commands, not only advertising the > write-only flag. Thanks, you put my (as usual) babblings into actually intelligible words :-) Cheers -- tomás signature.asc Description: Digital signature
Re: USB flash drive opens read only -- how to fix?
Le 03/10/2019 à 05:05, David Christensen a écrit : On 10/1/19 11:51 PM, to...@tuxteam.de wrote: Yep. Never forget -- there's a whole computer with its own OS in your flash drive. That "write protect" (sometimes) available as a physical switch is just communicated to your drivers via some protocol over USB. (...) It was my expectation that the write-protect switch is read by the flash drive controller, and that the flash drive controller will enforce read-only behavior (e.g. prohibiting writes). Do you have information indicating otherwise? On the contrary. The usb-storage module has a parameter "quirks" which allows to ignore the write-protect flag for a specific vid:pid device (I do not remember the exact syntax). I was afraid that it could be used to by-pass the write-protect switch so I tested it with my only flash drive with a write-protect switch on. Although the kernel considered the drive as writable, any write attempt resulted to an error. It is my understanding that Tomas meant that the write-protect switch does not cut the transmission of the electrical write signal to the flash memory chips and that the USB mass storage protocol also includes rejecting write commands, not only advertising the write-only flag.
Re: USB flash drive opens read only -- how to fix?
On 10/1/19 11:51 PM, to...@tuxteam.de wrote: Yep. Never forget -- there's a whole computer with its own OS in your flash drive. That "write protect" (sometimes) available as a physical switch is just communicated to your drivers via some protocol over USB. I have two such drives, both old and small (128 MB). But, I have contemplated buying new drives with the write protect switch. For example: https://www.kanguru.com/storage-accessories/kanguru-ss3.shtml It was my expectation that the write-protect switch is read by the flash drive controller, and that the flash drive controller will enforce read-only behavior (e.g. prohibiting writes). Do you have information indicating otherwise? David
Re: USB flash drive opens read only -- how to fix?
On Wed 02 Oct 2019 at 10:06:21 (-0400), Ken Heard wrote: > On 2019-10-01 11:03 p.m., David Christensen wrote: > > > I have read that some USB flash drives will revert to read-only > > mode when they detect an internal error. > > Makes sense I suppose, but in a negative way. I did not know that > flash drives (some? all?) do have this feature. > > > This gives the user a chance to copy out their data. > > I would have had to do so if the data there I needed to keep. > > > My limited experience with failing USB flash drives is that they go > > from read-write to read-only to useless in a matter of minutes or > > seconds. > > Strange. I had two other flash drives fail at about the same time; > both I was able to resuscitate with luksformat. Neither of those had > the ro marker. “All happy families are alike; each unhappy family is unhappy in its own way.” Leo Tolstoy, Anna Karenina (1878) Cheers, David.
Re: USB flash drive opens read only -- how to fix?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 2019-10-02 2:51 a.m., to...@tuxteam.de wrote, in part: > Yep. Never forget -- there's a whole computer with its own OS in > your flash drive. That "write protect" (sometimes) available as a > physical switch is just communicated to your drivers via some > protocol over USB. Interesting point. So it is likely a permanent hardware failure after all. Ken -BEGIN PGP SIGNATURE- iF0EARECAB0WIQR9YFyM2lJAhDprmoOU2UnM6QmZNwUCXZSvcQAKCRCU2UnM6QmZ N8P0AJ0bUEKWkFA3+jK7BDN5nOIEo9TwlgCfZJdf7QYj2vVh449m9F0HZnqmTiI= =JF3Z -END PGP SIGNATURE-
Re: USB flash drive opens read only -- how to fix?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 2019-10-01 11:03 p.m., David Christensen wrote: > I have read that some USB flash drives will revert to read-only > mode when they detect an internal error. Makes sense I suppose, but in a negative way. I did not know that flash drives (some? all?) do have this feature. > This gives the user a chance to copy out their data. I would have had to do so if the data there I needed to keep. > My limited experience with failing USB flash drives is that they go > from read-write to read-only to useless in a matter of minutes or > seconds. Strange. I had two other flash drives fail at about the same time; both I was able to resuscitate with luksformat. Neither of those had the ro marker. > What happens if you insert the USB drive into a Windows machine and > try to format it (cancel out before doing the actual format)? > macOS? FreeBSD? Other? I will have to try using it with other versions of the Turing machine as soon as I have access to same. Ken -BEGIN PGP SIGNATURE- iF0EARECAB0WIQR9YFyM2lJAhDprmoOU2UnM6QmZNwUCXZSu1wAKCRCU2UnM6QmZ N1n+AJ9Nixu4KhokPJNYbDES+fGakzDCiQCfWYa9G038uQMwB81/rD1f0BpQdOE= =ml+2 -END PGP SIGNATURE-
Re: USB flash drive opens read only -- how to fix?
On Tue, Oct 01, 2019 at 08:03:50PM -0700, David Christensen wrote: [...] > >How could this drive be physically protected from writing to it when > >there is no switch on the drive itself to unable (or release) such > >physical protection? > > > >Regards, Ken > > I have read that some USB flash drives will revert to read-only mode > when they detect an internal error [...] Yep. Never forget -- there's a whole computer with its own OS in your flash drive. That "write protect" (sometimes) available as a physical switch is just communicated to your drivers via some protocol over USB. Cheers -- t signature.asc Description: Digital signature
Re: USB flash drive opens read only -- how to fix?
On 10/1/19 4:32 PM, Ken Heard wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 2019-10-01 5:33 p.m., Pascal Hambourg wrote: Le 01/10/2019 à 23:09, Ken Heard a écrit : - - after unmounting and closing encryption running as root 'wipefs -a -f /dev/sdd' returns 'wipefs: error: /dev/sdd: probing initialization failed: Read-only file system'. The USB flash drive is probably physically write-protected. Check the kernel logs juste after inserting it for confirmation. Here are the kern.log entries created the most recent time this drive: Oct 1 19:25:21 SOL kernel: [28463.821015] usb 9-4: new SuperSpeed USB device number 15 using xhci_hcd Oct 1 19:25:21 SOL kernel: [28463.844007] usb 9-4: New USB device found, idVendor=0951, idProduct=1666 Oct 1 19:25:21 SOL kernel: [28463.844010] usb 9-4: New USB device strings: Mfr=1, Product=2, SerialNumber=3 Oct 1 19:25:21 SOL kernel: [28463.844012] usb 9-4: Product: DataTraveler 3.0 Oct 1 19:25:21 SOL kernel: [28463.844014] usb 9-4: Manufacturer: Kingst on Oct 1 19:25:21 SOL kernel: [28463.844016] usb 9-4: SerialNumber: 000AEB91EC07BD41230C0068 Oct 1 19:25:21 SOL kernel: [28463.845810] usb-storage 9-4:1.0: USB Mass Storage device detected Oct 1 19:25:21 SOL kernel: [28463.845973] scsi host9: usb-storage 9-4:1 .0 Oct 1 19:25:23 SOL kernel: [28464.861194] scsi 9:0:0:0: Direct-Access Kingston DataTraveler 3.0 PMAP PQ: 0 ANSI: 6 Oct 1 19:25:23 SOL kernel: [28464.861817] sd 9:0:0:0: [sdd] 61226496 512-byte logical blocks: (31.3 GB/29.2 GiB) Oct 1 19:25:23 SOL kernel: [28464.862088] sd 9:0:0:0: [sdd] Write Protect is off Oct 1 19:25:23 SOL kernel: [28464.862090] sd 9:0:0:0: [sdd] Mode Sense: 45 00 00 00 Oct 1 19:25:23 SOL kernel: [28464.862248] sd 9:0:0:0: Attached scsi generic sg4 type 0 Oct 1 19:25:23 SOL kernel: [28464.862365] sd 9:0:0:0: [sdd] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA Oct 1 19:25:23 SOL kernel: [28465.042599] sd 9:0:0:0: [sdd] Write Protect is on Oct 1 19:25:23 SOL kernel: [28465.042604] sd 9:0:0:0: [sdd] Mode Sense: 45 00 80 00 Oct 1 19:25:23 SOL kernel: [28465.043086] sd 9:0:0:0: [sdd] Attached SCSI removable disk Oct 1 19:25:37 SOL kernel: [28479.639563] EXT4-fs (dm-7): mounting ext2 file system using the ext4 subsystem Oct 1 19:25:37 SOL kernel: [28479.642175] EXT4-fs (dm-7): mounted filesystem without journal. Opts: (null) One entry says that Write protect is off, but a later entry says that is is on. How could this drive be physically protected from writing to it when there is no switch on the drive itself to unable (or release) such physical protection? Regards, Ken I have read that some USB flash drives will revert to read-only mode when they detect an internal error. This gives the user a chance to copy out their data. My limited experience with failing USB flash drives is that they go from read-write to read-only to useless in a matter of minutes or seconds. What happens if you insert the USB drive into a Windows machine and try to format it (cancel out before doing the actual format)? macOS? FreeBSD? Other? David
Re: USB flash drive opens read only -- how to fix?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 2019-10-01 5:33 p.m., Pascal Hambourg wrote: > Le 01/10/2019 à 23:09, Ken Heard a écrit : >> >> - - after unmounting and closing encryption running as root >> 'wipefs -a -f /dev/sdd' returns 'wipefs: error: /dev/sdd: probing >> initialization failed: Read-only file system'. > > The USB flash drive is probably physically write-protected. Check > the kernel logs juste after inserting it for confirmation. Here are the kern.log entries created the most recent time this drive: Oct 1 19:25:21 SOL kernel: [28463.821015] usb 9-4: new SuperSpeed USB device number 15 using xhci_hcd Oct 1 19:25:21 SOL kernel: [28463.844007] usb 9-4: New USB device found, idVendor=0951, idProduct=1666 Oct 1 19:25:21 SOL kernel: [28463.844010] usb 9-4: New USB device strings: Mfr=1, Product=2, SerialNumber=3 Oct 1 19:25:21 SOL kernel: [28463.844012] usb 9-4: Product: DataTraveler 3.0 Oct 1 19:25:21 SOL kernel: [28463.844014] usb 9-4: Manufacturer: Kingst on Oct 1 19:25:21 SOL kernel: [28463.844016] usb 9-4: SerialNumber: 000AEB91EC07BD41230C0068 Oct 1 19:25:21 SOL kernel: [28463.845810] usb-storage 9-4:1.0: USB Mass Storage device detected Oct 1 19:25:21 SOL kernel: [28463.845973] scsi host9: usb-storage 9-4:1 .0 Oct 1 19:25:23 SOL kernel: [28464.861194] scsi 9:0:0:0: Direct-Access Kingston DataTraveler 3.0 PMAP PQ: 0 ANSI: 6 Oct 1 19:25:23 SOL kernel: [28464.861817] sd 9:0:0:0: [sdd] 61226496 512-byte logical blocks: (31.3 GB/29.2 GiB) Oct 1 19:25:23 SOL kernel: [28464.862088] sd 9:0:0:0: [sdd] Write Protect is off Oct 1 19:25:23 SOL kernel: [28464.862090] sd 9:0:0:0: [sdd] Mode Sense: 45 00 00 00 Oct 1 19:25:23 SOL kernel: [28464.862248] sd 9:0:0:0: Attached scsi generic sg4 type 0 Oct 1 19:25:23 SOL kernel: [28464.862365] sd 9:0:0:0: [sdd] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA Oct 1 19:25:23 SOL kernel: [28465.042599] sd 9:0:0:0: [sdd] Write Protect is on Oct 1 19:25:23 SOL kernel: [28465.042604] sd 9:0:0:0: [sdd] Mode Sense: 45 00 80 00 Oct 1 19:25:23 SOL kernel: [28465.043086] sd 9:0:0:0: [sdd] Attached SCSI removable disk Oct 1 19:25:37 SOL kernel: [28479.639563] EXT4-fs (dm-7): mounting ext2 file system using the ext4 subsystem Oct 1 19:25:37 SOL kernel: [28479.642175] EXT4-fs (dm-7): mounted filesystem without journal. Opts: (null) One entry says that Write protect is off, but a later entry says that is is on. How could this drive be physically protected from writing to it when there is no switch on the drive itself to unable (or release) such physical protection? Regards, Ken -BEGIN PGP SIGNATURE- iF0EARECAB0WIQR9YFyM2lJAhDprmoOU2UnM6QmZNwUCXZPiFQAKCRCU2UnM6QmZ N5LyAJ90ESCk5g0fJa6tnqPeCClmjhXX+wCfb7feHPTKEm6dkAxOpb1yT8nU5VA= =3RCx -END PGP SIGNATURE-
Re: USB flash drive opens read only -- how to fix?
Le 01/10/2019 à 23:09, Ken Heard a écrit : - - after unmounting and closing encryption running as root 'wipefs -a -f /dev/sdd' returns 'wipefs: error: /dev/sdd: probing initialization failed: Read-only file system'. The USB flash drive is probably physically write-protected. Check the kernel logs juste after inserting it for confirmation.
USB flash drive opens read only -- how to fix?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Messieurs et mesdames: Command 'mount' returns among other things the following two lines: /dev/mapper/fde on /media/fde type ext2\ (rw,nosuid,nodev,noexec,noatime,block_validity,barrier,user_xattr,acl) /dev/mapper/fdc on /media/fdc type ext2\ (ro,nosuid,nodev,noexec,noatime,block_validity,barrier,user_xattr,acl) The first line above (divided into two here) is what 'mount' shows for all my encrypted USB flash drives when opened -- they are all opened with 'rw'. The second lino above is what is shown for only one of my incrypted USB flash drives; it opens with 'ro'. When this drive is opened and mounted the message returned is 'mount: /dev/mapper/fdc is write-protected, mounting read-only'. This situation is very strange. Something somewhere causes this drive to be opened 'ro' instead of the 'rw' specified for this mount point in file /etc/fstab. Not only can I not find out where I cannot find a way make this drive 'rw'. It is consequently useless. Among the workarounds I tried are: - - the commands 'sudo chmod' to change permissions. (I own the directories and files in the drive.) - - after dismounting the drive but keeping the encryption open running 'sudo mount -o remount,rw /media/fdc' which returns the same message mentioned above: 'mount: /dev/mapper/fdc is write-protected, mounting read-only'. - - after unmounting and closing encryption running as root 'wipefs -a -f /dev/sdd' returns 'wipefs: error: /dev/sdd: probing initialization failed: Read-only file system'. - - 'sudo luksformat -t ext2' /dev/sdd after going through the preliminaries returns 'Could not create LUKS device /dev/sdd at /usr/sbin/luksformat line 91, line 30' - - 'sudo mkfs.ext2 /dev/sdd' after asking if I really want to go ahead with this command returns '/dev/sdd: Read-only file system while setting up superblock'. After some on line searches it appears that to regain use of this flash drive (it contains no essential data) I will have to go through several steps to erase LUKS and then use the 'dd' command to wipe the drive clean. I am still afraid to use that command because of the potential damage that can be caused by one or more bad 'if' and 'of' settings if there is not an easier way. Does anyone here know of one? In any event I would surely know how this situation would arise in the first place. Regards, Ken Heard -BEGIN PGP SIGNATURE- iF0EARECAB0WIQR9YFyM2lJAhDprmoOU2UnM6QmZNwUCXZPAiAAKCRCU2UnM6QmZ N5HJAJ9S/haC6nE8/EkuhXtCETZimi8mzQCeO7BmV2pKWO4TuPMkcJTH/71nMDY= =04oO -END PGP SIGNATURE-
