Re: gfs2_fh_to_parent() array overflow

[Adrian Bunk <bunk@kernel.org>]

On Mon, Oct 29, 2007 at 09:11:21AM +0000, Steven Whitehouse wrote:
> Hi,
> 
> On Sat, 2007-10-27 at 23:00 +0200, Christoph Hellwig wrote:
> > On Wed, Oct 24, 2007 at 06:26:26PM +0200, Adrian Bunk wrote:
> > > The Coverity checker spotted the following array overflow caused by
> > > commit 34c0d154243dd913c5690ae6ceb9557017429b9c:
> > 
> > The line is a left-over from times when gfs stored the mode of the
> > inode in the file handle.  It can simply be deleted.  Steve, do you
> > want a patch for that or could you commit that one-liner directly?
> > 
> 
> I'm just back from holiday this morning and this is looking a bit more
> complicated than that... give me a day or two and I'll try and come up
> with a solution,

This issue is still present in 2.6.25-rc1.

> Steve.
> 
> > > fs/gfs2/ops_export.c contains:
> > > 
> > > <--  snip  -->
> > > 
> > > ...
> > > static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid,
> > >                 int fh_len, int fh_type)
> > > {
> > >         struct gfs2_inum_host parent;
> > >         __be32 *fh = (__force __be32 *)fid->raw;  <------------
> > > 
> > >         switch (fh_type) {
> > >         case GFS2_LARGE_FH_SIZE:
> > >         case GFS2_OLD_FH_SIZE:
> > >                 parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
> > >                 parent.no_formal_ino |= be32_to_cpu(fh[5]);
> > >                 parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
> > >                                                    ^^^^^
> > >                 parent.no_addr |= be32_to_cpu(fh[7]);
> > > ...                                           ^^^^^
> > > 
> > > <--  snip  -->
> > > 
> > > 
> > > cu
> > > Adrian
> > > 

cu
Adrian

-- 

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