Re: [Xen-devel] [PATCH for-4.5 v2] libxc: don't leak buffer containing the uncompressed PV kernel

[Ian Campbell <Ian.Campbell@xxxxxxxxxx>]

On Tue, 2014-11-25 at 16:24 +0000, Ian Campbell wrote:
> On Thu, 2014-11-20 at 16:03 +0000, Wei Liu wrote:
> > On Thu, Nov 20, 2014 at 03:48:47PM +0000, Ian Campbell wrote:
> > > The libxc xc_dom_* infrastructure uses a very simple malloc memory pool 
> > > which
> > > is freed by xc_dom_release. However the various xc_try_*_decode routines 
> > > (other
> > > than the gzip one) just use plain malloc/realloc and therefore the buffer 
> > > ends
> > > up leaked.
> > > 
> > > The memory pool currently supports mmap'd buffers as well as a directly
> > > allocated buffers, however the try decode routines make use of realloc 
> > > and do
> > > not fit well into this model. Introduce a concept of an external memory 
> > > block
> > > to the memory pool and provide an interface to register such memory.
> > > 
> > > The mmap_ptr and mmap_len fields of the memblock tracking struct lose 
> > > their
> > > mmap_ prefix since they are now also used for external memory blocks.
> > > 
> > > We are only seeing this now because the gzip decoder doesn't leak and 
> > > it's only
> > > relatively recently that kernels in the wild have switched to better
> > > compression.
> > > 
> > > This is https://bugs.debian.org/767295
> > > 
> > > Reported by: Gedalya <gedalya@xxxxxxxxxxx>
> > > Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
> > 
> > Reviewed-by: Wei Liu <wei.liu2@xxxxxxxxxx>
> 
> Thanks. Konrad release-acked on IRC so I've applied.

Ian: THis one should be backported I think.


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel