** Description changed: + [SRU Justification] + Since trusty, using mcopy to create directories will result in corrupted FAT entries due to uninitialized memory. This leads to data loss when an fsck is run on the filesystem. + + [Test case] + 1. Run the script from https://bugs.launchpad.net/ubuntu/+source/mtools/+bug/1619718/comments/2 + 2. Observe that you are prompted to fix corrupted filesystem entries + 3. Install mtools from xenial-proposed + 4. Run the reproducer.sh script again + 5. Observe that the newly-created filesystem passes fsck with no errors. + + [Regresion potential] + This is a one-line fix to correct uninitialized memory. The only regression potential is that associated with rebuilding the tools with a new toolchain (the last rebuild of these binary packages was in vivid, with gcc-4.9). + + [Original bug description] + on arm images the vfat used for the boot partition corrupts itself after a few reboots (it is noteworthy that on uboot/arm installations we write a lot more to the vfat. i would actually expect this to happen on x86 systems as well, just a lot later, i.e. after a few kernel updates) there seem to be various differences in how ubuntu-image creates the vfat ... in ubuntu-device-flash we use: mkfs.vfat -F 32 -S 512 -n ... against a loop mounted partition, the -S 512 value gets actually matched against blockdev --getss (and adjusted accordingly if needed) ubuntu-image currently only calls: "mkfs.vfat" without any options against an img file that represents the vfat content. u-d-f also just uses cp against the loop mounted partition while ubuntu- image uses mtools' mcopy to put the files in place ... the result is that at random boots fsck suddenly starts to rename files in an 8+3 scheme like: http://paste.ubuntu.com/23124260/ or http://paste.ubuntu.com/23124139/ which results in http://paste.ubuntu.com/23123498/ i spent the whole day trying to tweak the mkfs options but to no avail, the corruption always happens at some point, so my suspicion goes more towards mtools/mcopy now http://paste.ubuntu.com/23123789/ is the original code that u-d-f uses which does not show such behaviour (i have upgraded the u-d-f rpi2 image over the last 6 weeks daily with new ubuntu-core and occasionally with new pi2-kernel packages without any corruption)
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1619718 Title: ubuntu-image created vfat eats itself after a while (mcopy creates wrong subdirs) To manage notifications about this bug go to: https://bugs.launchpad.net/snappy/+bug/1619718/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
