Re: [PATCHv3] sunrpc/auth_gss: NULL pointer deref in gss_pipe_release()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 8/14/06, Trond Myklebust <[email protected]> wrote:
On Mon, 2006-08-14 at 16:34 -0400, Alex Polvi wrote:
> On 8/14/06, Alex Polvi <[email protected]> wrote:
> > Here is another fix. It is quite silly, but clnt->cl_auth is set to
> > NULL in rpc_destroy_client(), then eventually referenced in
> > gss_release_pipe() via rpc_rmdir(). Simply removing the clnt->cl_auth
> > = NULL from clnt.c fixes the issue. I'm still trying to understand the
> > subsystem, but it seems like rpc_rmdir is being correctly called to
> > clean up because of the weirdness with umount -l and the nfs server
> > being turned on and off. Does that seem correct? Or is this still just
> > covering up some other part of the code being sloppy cleaning up?
>
> Also, I just want to make it clear that I do not think this is the
> proper fix. It is just pointing out that we intentionally set cl_auth
> to NULL, then reference it.

OK. I think I've finally managed to clean up the various interactions
with rpc_pipefs. I've uploaded a series of patches on the NFS client
website. See

  http://client.linux-nfs.org/Linux-2.6.x/2.6.18-rc4/

The relevant patches are

linux-2.6.18-006-fix_rpc_unlink.dif:

        From: Trond Myklebust <[email protected]>

        SUNRPC: make rpc_unlink() take a dentry argument instead of a
        path

        Signe-off-by: Trond Myklebust <[email protected]>

linux-2.6.18-007-fix_rpc_rmdir.dif:

        From: Trond Myklebust <[email protected]>

        NFS: clean up rpc_rmdir

        Make it take a dentry argument instead of a path

        Signed-off-by: Trond Myklebust <[email protected]>

linux-2.6.18-008-fix_rpc_unlink_rmdir_2.dif:

        From: Trond Myklebust <[email protected]>

        SUNRPC: rpc_unlink() must check for unhashed dentries

        A prior call to rpc_depopulate() by rpc_rmdir() on the parent
        directory may have already called simple_unlink() on this entry.
        Add the same check to rpc_rmdir(). Also remove a redundant call
        to rpc_close_pipes() in rpc_rmdir.

        Signed-off-by: Trond Myklebust <[email protected]>

linux-2.6.18-009-fix_rpc_unlink_rmdir_3.dif:

        From: Trond Myklebust <[email protected]>

        SUNRPC: Fix dentry refcounting issues with users of rpc_pipefs

        rpc_unlink() and rpc_rmdir() will dput the dentry reference for
        you.

        Signed-off-by: Trond Myklebust <[email protected]>

Wooohooooo!!!! I can confirm that it fixes my testcase. I'll let you
know if I run into any problems.

Thanks again for all your help figuring this one out!

-Alex
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux