Red Hat Bugzilla – Bug 49493
mc undeletion feature trashed ext2 partition
Last modified: 2013-04-02 00:15:29 EDT
From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.2) Gecko/20010628 Description of problem: I tried to use the undeletion feature in mc to undelete some files from an ext2 filesystem. The filesystem was silently corrupted, which meant eventually all the data was lost (thank goodness for backups!). I unmounted the partition. In mc I entered the undeletion mode, and copied the deleted files to the root partition. I then remounted the partition. This was sufficient. Unless this is a hardware fault (I didn't see any hardware error messages in the logs), and not software (dodgy kernel or something - we're using the latest RH 2.4.3-12), then I suggest mc's undeletion is disabled until it is tested. Hardware: Pentium II machine, with ~14 Gb ext2 partition on an IDE disk. fscking partition found lots of errors, and overlapping files. The end result was a big mess which couldn't be easily recovered. How reproducible: Didn't try Steps to Reproduce: 1. Unmount ext2 partition 2. Use mc undeletion feature 3. Remount ext2 partition 4. Data becomes corrupted Actual Results: file system is corrupted. Additional info:
Not related to this bug, but you're advised to use this great undeletion utility: http://recover.sourceforge.net/linux/recover/ _Much_ faster and user-friendly. Btw, mc's undelete mode is read-only, I think. At least I recall I've used it on read-only mounted partitions.
I don't believe it is even possible for mc to corrupt a partition with undelfs at least last time I looked at the source code. It is read only. Are you absolutely positive that it corrupted the fs, and not anything else?
It was the only thing which I ran on the drive between unmounting and mounting the partition. I can't remember whether I fsck'd the drive after unmounting it, so it could have been corrupt before, but there weren't any obvious errors. I can't be certain whether mc was the problem. I'd like to do some tests on the undeletion feature, but I haven't got time at the moment.
The most we'd do here is disable the undelete feature, no active hacking goes in to mc on the Red Hat side. Don't know of any reports against 7.2 and the next release will have a newer mc, so those may well fix the problem.