Ack: [Trusty][SRU][PATCH 0/1] btrfs: fix defrag 32-bit integer overflow

Brad Figg brad.figg at canonical.com
Wed Jun 18 17:02:05 UTC 2014


On 06/18/2014 09:20 AM, Joseph Salisbury wrote:
> BugLink: http://bugs.launchpad.net/bugs/1324953
> 
> == Trusty SRU Justification ==
> A kernel crash happens when defragmenting large files on Trusty using btrfs.  When defragging a very large file, the cluster variable can wrap its 32-bit signed int type and become negative, which eventually gets passed to btrfs_force_ra() as a very large unsigned long value.  On 32-bit platforms, this eventually results in an Oops from the SLAB allocator.  This issue is fixed in mainline as of 3.14-rc2.  However, the fix was not cc'd to stable.
>   
> == Fix ==
> commit c41570c9d29764f797fa35490d72b7395a0105c3
> Author: Justin Maggard <jmaggard10 at gmail.com>
> Date:   Tue Jan 21 11:18:29 2014 -0800
> 
>     btrfs: fix defrag 32-bit integer overflow
> 
> == Test Case ==
> 
> A test kernel was built with this patch and tested by the original bug reporter.  The bug reporter states the test kernel resolved the bug.
> 
> Justin Maggard (1):
>   btrfs: fix defrag 32-bit integer overflow
> 
>  fs/btrfs/ioctl.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 

Looks like a clean cherry-pick.

-- 
Brad Figg brad.figg at canonical.com http://www.canonical.com




More information about the kernel-team mailing list