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artful' to 'verification-done-artful'. If the problem still exists,
change the tag 'verification-needed-artful' to 'verification-failed-

If verification is not done by 5 working days from today, this fix will
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** Tags added: verification-needed-artful

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Touch seeded packages, which is subscribed to tar in Ubuntu.

  btrfs and tar sparse truncate archives

Status in linux package in Ubuntu:
  Fix Released
Status in tar package in Ubuntu:
Status in linux source package in Artful:
  Fix Committed
Status in tar source package in Artful:

Bug description:
  == SRU Justification ==
  This bug causes btrfs and tar sparse to truncate archives.  This bug has been 
  fixed in v4.15-rc3 by commit e3b8a4858566, which has a prereq commit of 

  These commits were cc'd to upstream stable and are already in Bionic.  
However, upstream
  4.13 is EOL, so Artful never recieved the fixes, which is the reason for
  the SRU request.

  == Fixes ==
  f48bf66b662e ("Btrfs: move definition of the function 
  e3b8a4858566 ("Btrfs: fix reported number of inode blocks after buffered 
append writes")

  == Regression Potential ==
  Low.  This fix was also sent and accepted to stable, so it has had additional 
upstream review.

  == Test Case ==
  A test kernel was built with these patches and tested by the original bug 
  The bug reporter states the test kernel resolved the bug.

  root@ubuntu:~# lsb_release -rd
  Description:  Ubuntu 17.10
  Release:      17.10
  root@ubuntu:~# apt-cache policy linux-image-virtual
    Version table:
   *** 500
          500 artful-updates/main amd64 
          500 artful-security/main amd64 
          100 /var/lib/dpkg/status 500
          500 artful/main amd64 Packages

  3. Taring files into an archive are not truncated
  4. Files included in tar are filled with NULLs

  To reproduce, run an Artful system with one spare disk:

  - mkfs.btrfs -f /dev/sda
  - mount /dev/sda /mnt
  - grep sda /proc/mounts
  /dev/sda /mnt btrfs rw,relatime,space_cache,subvolid=5,subvol=/ 0 0

  Then run this script which copies a 4MB binary to a btrfs filesystem,
  tars the directory up containing the binary; then untars to stdout and
  md5sum compares, showing it's different.

  % SPARSE="-S"; rm -rf /mnt/tmp; md5sum /usr/bin/python3.6; mkdir -p /mnt/tmp; 
cp -a /usr/bin/python3.6 /mnt/tmp; tar -C /mnt/tmp $SPARSE -czf /mnt/test.tgz 
.; tar $SPARSE -xzf /mnt/test.tgz -O | md5sum
  e4121d2f3126b8c364bfa1aaa82371a3  /usr/bin/python3.6
  0ce8c4139740198926273853defcb12a  -

  And now without the sparse flag:

  # SPARSE=""; rm -rf /mnt/tmp; md5sum /usr/bin/python3.6; mkdir -p /mnt/tmp; 
cp -a /usr/bin/python3.6 /mnt/tmp; tar -C /mnt/tmp $SPARSE -czf /mnt/test.tgz 
.; tar $SPARSE -xzf /mnt/test.tgz -O | md5sum
  e4121d2f3126b8c364bfa1aaa82371a3  /usr/bin/python3.6
  e4121d2f3126b8c364bfa1aaa82371a3  -

  This has been reported to both gnu-tar and linux-btrfs; I'm not aware of an 
actual fix.
  Note that Xenial 4.4 kernels do not exhibit this behavior, and Bionic 4.15 
kernel appears to be fixed as well though I'm not sure what the difference is.


  ProblemType: Bug
  DistroRelease: Ubuntu 17.10
  Package: linux-image-virtual
  ProcVersionSignature: Ubuntu 4.13.0-37.42-generic 4.13.13
  Uname: Linux 4.13.0-37-generic x86_64
   total 0
   crw-rw---- 1 root audio 116,  1 Mar 21 22:55 seq
   crw-rw---- 1 root audio 116, 33 Mar 21 22:55 timer
  AplayDevices: Error: [Errno 2] No such file or directory: 'aplay': 'aplay'
  ApportVersion: 2.20.7-0ubuntu3.7
  Architecture: amd64
  ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord': 
  AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', 
'/dev/snd/timer'] failed with exit code 1:
  Date: Wed Mar 21 23:08:05 2018
  IwConfig: Error: [Errno 2] No such file or directory: 'iwconfig': 'iwconfig'
  Lsusb: Error: command ['lsusb'] failed with exit code 1:
  MachineType: QEMU Standard PC (i440FX + PIIX, 1996)

   PATH=(custom, no user)

  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.13.0-37-generic 
root=LABEL=cloudimg-rootfs ro console=tty1 console=ttyS0
   linux-restricted-modules-4.13.0-37-generic N/A
   linux-backports-modules-4.13.0-37-generic  N/A
   linux-firmware                             N/A
  RfKill: Error: [Errno 2] No such file or directory: 'rfkill': 'rfkill'
  SourcePackage: linux
  UpgradeStatus: No upgrade log present (probably fresh install) 04/01/2014
  dmi.bios.vendor: SeaBIOS
  dmi.bios.version: Ubuntu-1.8.2-1ubuntu1
  dmi.chassis.type: 1
  dmi.chassis.vendor: QEMU
  dmi.chassis.version: pc-i440fx-xenial
dmi:bvnSeaBIOS:bvrUbuntu-1.8.2-1ubuntu1:bd04/01/2014:svnQEMU:pnStandardPC(i440FX+PIIX,1996):pvrpc-i440fx-xenial:cvnQEMU:ct1:cvrpc-i440fx-xenial: Standard PC (i440FX + PIIX, 1996)
  dmi.product.version: pc-i440fx-xenial
  dmi.sys.vendor: QEMU

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