Re: [PATCH 0/2] xfsdump: fix problems in cb_add_inogrp

[Rich Johnston <rjohnston@xxxxxxx>]

On 08/21/2015 11:39 AM, Eric Sandeen wrote:
> On 8/21/15 11:38 AM, Rich Johnston wrote:
> > On 08/21/2015 10:47 AM, Eric Sandeen wrote:
> > > On 8/21/15 9:01 AM, rjohnston@xxxxxxx wrote:
> > > > The memset in cb_add_inogrp will segfault when the index oldsize
> > > > overflows. In cb_add_inogrp(), the temp variables used in
> > > > calculating the new i2gmap segment offset should be int64 instead
> > > > of intgen_t (int32).
> > > >
> > > > A second bug also occurs because we already compensate for the
> > > > length of each item in oldsize so are 32bit wrap becomes a 40bit
> > > > wrap.
> > > Hi -
> > >
> > > Are there any testcases for these?  xfsdump is alien code, I swear;
> > > I'm not quite sure offhand how to tickle any of these bugs.
> > >
> > > Thanks,
> > > -Eric
> > No I thought simple examination shows the bug.
> Nothing is simple in xfsdump, IMHO.  At least to the uninitiated.  :)
:)
> > It was a customer bug.
> >
> > The number of inodes that we needed before wrapping was a couple hundred inodes.
                                                                    ^^^^
make that *million*
> I did eventually manage to hit the segfault, thanks.
>
> -Eric