[lustre-devel] [PATCH 8/8] lustre: ldlm: Don't check opcode with NULL rq_reqmsg

[Andreas Dilger]

The ldlm code on the client acts as a "server" for some RPCs from the
OSS and MDS, namely lock cancellation and granting callbacks
(ASTs).

So even if some of this looks like server code it is also used on the client. 

Cheers, Andreas

> On Jul 24, 2019, at 19:44, James Simmons <jsimmons at infradead.org> wrote:
> 
> From: Jeremy Filizetti <jeremy.filizetti at gmail.com>
> 
> When GSS is enabled it's possible to have a NULL rq_reqmsg
> if a bad signature or no context is returned during the unwrap
> of the request.  Don't check the opcode in this case.
> 
> WC-bug-id: https://jira.whamcloud.com/browse/LU-7508
> Lustre-commit: 3f4572caef5f25f4a9b5347b2ccf933fdad9db9c
> Signed-off-by: Jeremy Filizetti <jeremy.filizetti at gmail.com>
> Reviewed-on: http://review.whamcloud.com/17414
> Reviewed-by: Andreas Dilger <adilger at whamcloud.com>
> Reviewed-by: Sebastien Buisson <sbuisson at ddn.com>
> Reviewed-by: John L. Hammond <jhammond at whamcloud.com>
> ---
> fs/lustre/ldlm/ldlm_lib.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/lustre/ldlm/ldlm_lib.c b/fs/lustre/ldlm/ldlm_lib.c
> index a3b8df4..04982b8 100644
> --- a/fs/lustre/ldlm/ldlm_lib.c
> +++ b/fs/lustre/ldlm/ldlm_lib.c
> @@ -689,8 +689,12 @@ int target_pack_pool_reply(struct ptlrpc_request *req)
>        DEBUG_REQ(D_ERROR, req, "dropping reply");
>        return -ECOMM;
>    }
> -    if (unlikely(lustre_msg_get_opc(req->rq_reqmsg) == MDS_REINT &&
> -             OBD_FAIL_CHECK(OBD_FAIL_MDS_REINT_MULTI_NET_REP)))
> +    /* We can have a null rq_reqmsg in the event of bad signature or
> +     * no context when unwrapping
> +     */
> +    if (req->rq_reqmsg &&
> +        unlikely(lustre_msg_get_opc(req->rq_reqmsg) == MDS_REINT &&
> +        OBD_FAIL_CHECK(OBD_FAIL_MDS_REINT_MULTI_NET_REP)))
>        return -ECOMM;
> 
>    if (unlikely(rc)) {
> -- 
> 1.8.3.1
>