hardy-xen: fix a potential resource leak

[Stefan Bader]

SRU Justification:

Impact: This only affects the xen custom kernel. When applying patches to fix CVE-2010-4247, a follow-up patch was missed that would fix a potention leak. This will only happen in the error case when the loop is prematurely ended.

Fix: Patch taken from Xen repository.

Testcase: none, found by code review and not sure how to trigger the error case the first place.

[Herton R. Krzesinski (herton)]

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-hardy' to 'verification-done-hardy'.

If verification is not done by one week from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Stefan Bader (smb)]

As I wrote in the description this is a follow-up for a CVE update. We had no real reproducer for the CVE and the resource leak would only happen in that error path. But the patch basically just moves the exit conditions around so it does not allocate a request and then exits but does it before. Marking it verified based on that.

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 2.6.24-29.91

---------------
linux (2.6.24-29.91) hardy-proposed; urgency=low

  [Steve Conklin]

  * Release Tracking Bug
    - LP: #801636

  [Andy Whitcroft]

  * custom binaries need VERSION_SIGNATURE updated during prepare
    - LP: #794698

  [Stefan Bader]

  * (config) Disable COMPAT_VDSO for i386 Xen kernels
    - LP: #794715
  * XEN: Add yield points to blktap and blkback
    - LP: #791212
    - CVE-2010-4247
  * xen: Fix memory corruption caused by double free
    - LP: #705562

  [Upstream Kernel Changes]

  * agp: fix arbitrary kernel memory writes, CVE-1011-2022
    - LP: #788684
    - CVE-1011-2022
  * agp: fix OOM and buffer overflow
    - LP: #791918
    - CVE-2011-1746
  * tty: icount changeover for other main devices, CVE-2010-4076,
    CVE-2010-4077
    - LP: #794034
    - CVE-2010-4077
  * fs/partitions/efi.c: corrupted GUID partition tables can cause kernel
    oops
    - LP: #795418
    - CVE-2011-1577
  * Fix corrupted OSF partition table parsing
    - LP: #796606
    - CVE-2011-1163
  * proc: avoid information leaks to non-privileged processes
    - LP: #799906
    - CVE-2011-0726
  * proc: protect mm start_code/end_code in /proc/pid/stat
    - LP: #799906
    - CVE-2011-0726
  * sctp: Fix a race between ICMP protocol unreachable and connect()
    - LP: #799828
    - CVE-2010-4526
  * xen: blkback, blktap: Fix potential resource leak
    - LP: #800254
 -- Steve Conklin <email address hidden> Fri, 24 Jun 2011 10:59:11 -0500