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[oleg <overlayfs@xxxxxxxxx>]

** Description changed:

  rm -r * fails to delete directories when using overlayfs in a user-
  namespace.
  
  If overlayfs is mounted as follows,
  
-    mount -n -t overlay overlay -o
+    mount -n -t overlay overlay -o
  lowerdir=lowerdir,upperdir=upperdir,workdir=workdir mntpt
  
  and if lowerdir contains lowerdir/foo/bar.txt, then,
  
-    rm -r mntpt/foo
+    rm -r mntpt/foo
  
  fails with error message,
  
-    "rm: cannot remove ‘mntpt/foo’: Operation not permitted"
+    "rm: cannot remove ‘mntpt/foo’: Operation not permitted"
  
  strace shows,
  
-     unlinkat(AT_FDCWD, "mntpt/foo", AT_REMOVEDIR) = -1 EPERM (Operation
+     unlinkat(AT_FDCWD, "mntpt/foo", AT_REMOVEDIR) = -1 EPERM (Operation
  not permitted)
  
  OS details: 64-bit ubuntu 14.04.2 with the linux-generic-lts-vivid
  kernel.
  
- The bug does not occur with the default 3.13 kernel.  The bug occurs for any vanilla 3.18+ kernel to which the 1-line patch, "overlayfs: allow unprivileged mounts" is added.  (The patch is at, http://kernel.ubuntu.com/git/ubuntu/ubuntu-vivid.git/commit/?id=78ec45495b15d27d4cc6d05cc454e30ec5b587ea)
-  
- The bug occurs regardless of whether the underlying filesystem is tmpfs or ext4.
+ The bug does not occur with the default 3.13 kernel.  The bug occurs for
+ any vanilla 3.18+ kernel to which the 1-line patch, "overlayfs: allow
+ unprivileged mounts" is added.  (The patch is at,
+ http://kernel.ubuntu.com/git/ubuntu/ubuntu-
+ vivid.git/commit/?id=78ec45495b15d27d4cc6d05cc454e30ec5b587ea)
+ 
+ The bug occurs regardless of whether the underlying filesystem is tmpfs
+ or ext4.
+ 
+ The bug also occurs when running ubuntu 15.04 (ubuntu vivid) in a
+ virtual machine (qemu-kvm).   The host is ubuntu 14.04 with the linux-
+ generic-lts-vivid kernel.
  
  A script which reproduces the bug is attached and is also available at
  http://paste.ubuntu.com/11974137/
  
  Hardware: intel core2 duo processor in a macbook-4.1

** Tags added: bot-stop-nagging

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https://bugs.launchpad.net/bugs/1480411

Title:
  rm -r * fails to delete directories when using overlayfs in a user-
  namespace

Status in linux package in Ubuntu:
  Triaged

Bug description:
  rm -r * fails to delete directories when using overlayfs in a user-
  namespace.

  If overlayfs is mounted as follows,

     mount -n -t overlay overlay -o
  lowerdir=lowerdir,upperdir=upperdir,workdir=workdir mntpt

  and if lowerdir contains lowerdir/foo/bar.txt, then,

     rm -r mntpt/foo

  fails with error message,

     "rm: cannot remove ‘mntpt/foo’: Operation not permitted"

  strace shows,

      unlinkat(AT_FDCWD, "mntpt/foo", AT_REMOVEDIR) = -1 EPERM
  (Operation not permitted)

  OS details: 64-bit ubuntu 14.04.2 with the linux-generic-lts-vivid
  kernel.

  The bug does not occur with the default 3.13 kernel.  The bug occurs
  for any vanilla 3.18+ kernel to which the 1-line patch, "overlayfs:
  allow unprivileged mounts" is added.  (The patch is at,
  http://kernel.ubuntu.com/git/ubuntu/ubuntu-
  vivid.git/commit/?id=78ec45495b15d27d4cc6d05cc454e30ec5b587ea)

  The bug occurs regardless of whether the underlying filesystem is
  tmpfs or ext4.

  The bug also occurs when running ubuntu 15.04 (ubuntu vivid) in a
  virtual machine (qemu-kvm).   The host is ubuntu 14.04 with the linux-
  generic-lts-vivid kernel.

  A script which reproduces the bug is attached and is also available at
  http://paste.ubuntu.com/11974137/

  Hardware: intel core2 duo processor in a macbook-4.1

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