diff mbox series

[rfc,1/2] nfsd: don't assume copy notify when preprocessing the stateid

Message ID 20240724170138.1942307-1-sagi@grimberg.me (mailing list archive)
State New
Headers show
Series [rfc,1/2] nfsd: don't assume copy notify when preprocessing the stateid | expand

Commit Message

Sagi Grimberg July 24, 2024, 5:01 p.m. UTC
Move the stateid handling to nfsd4_copy_notify, if nfs4_preprocess_stateid_op
did not produce an output stateid, error out.

Copy notify specifically does not permit the use of special stateids,
so enforce that outside generic stateid pre-processing.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
---
 fs/nfsd/nfs4proc.c  | 4 +++-
 fs/nfsd/nfs4state.c | 6 +-----
 2 files changed, 4 insertions(+), 6 deletions(-)

Comments

Chuck Lever July 24, 2024, 5:06 p.m. UTC | #1
Adding Olga for her review and comments.

On Wed, Jul 24, 2024 at 10:01:37AM -0700, Sagi Grimberg wrote:
> Move the stateid handling to nfsd4_copy_notify, if nfs4_preprocess_stateid_op
> did not produce an output stateid, error out.
> 
> Copy notify specifically does not permit the use of special stateids,
> so enforce that outside generic stateid pre-processing.
> 
> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
> ---
>  fs/nfsd/nfs4proc.c  | 4 +++-
>  fs/nfsd/nfs4state.c | 6 +-----
>  2 files changed, 4 insertions(+), 6 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> index 46bd20fe5c0f..7b70309ad8fb 100644
> --- a/fs/nfsd/nfs4proc.c
> +++ b/fs/nfsd/nfs4proc.c
> @@ -1942,7 +1942,7 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  	struct nfsd4_copy_notify *cn = &u->copy_notify;
>  	__be32 status;
>  	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
> -	struct nfs4_stid *stid;
> +	struct nfs4_stid *stid = NULL;
>  	struct nfs4_cpntf_state *cps;
>  	struct nfs4_client *clp = cstate->clp;
>  
> @@ -1951,6 +1951,8 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  					&stid);
>  	if (status)
>  		return status;
> +	if (!stid)
> +		return nfserr_bad_stateid;
>  
>  	cn->cpn_lease_time.tv_sec = nn->nfsd4_lease;
>  	cn->cpn_lease_time.tv_nsec = 0;
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 69d576b19eb6..dc61a8adfcd4 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -7020,11 +7020,7 @@ nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
>  		*nfp = NULL;
>  
>  	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid)) {
> -		if (cstid)
> -			status = nfserr_bad_stateid;
> -		else
> -			status = check_special_stateids(net, fhp, stateid,
> -									flags);
> +		status = check_special_stateids(net, fhp, stateid, flags);
>  		goto done;
>  	}
>  
> -- 
> 2.43.0
> 
>
Olga Kornievskaia July 24, 2024, 7:12 p.m. UTC | #2
On Wed, Jul 24, 2024 at 1:06 PM Chuck Lever <chuck.lever@oracle.com> wrote:
>
> Adding Olga for her review and comments.
>
> On Wed, Jul 24, 2024 at 10:01:37AM -0700, Sagi Grimberg wrote:
> > Move the stateid handling to nfsd4_copy_notify, if nfs4_preprocess_stateid_op
> > did not produce an output stateid, error out.
> >
> > Copy notify specifically does not permit the use of special stateids,
> > so enforce that outside generic stateid pre-processing.

I dont see how this patch is accomplishing this. As far as I can tell
(just by looking at the code without actually testing it) instead it
does exactly the opposite.

> >
> > Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
> > ---
> >  fs/nfsd/nfs4proc.c  | 4 +++-
> >  fs/nfsd/nfs4state.c | 6 +-----
> >  2 files changed, 4 insertions(+), 6 deletions(-)
> >
> > diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> > index 46bd20fe5c0f..7b70309ad8fb 100644
> > --- a/fs/nfsd/nfs4proc.c
> > +++ b/fs/nfsd/nfs4proc.c
> > @@ -1942,7 +1942,7 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> >       struct nfsd4_copy_notify *cn = &u->copy_notify;
> >       __be32 status;
> >       struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
> > -     struct nfs4_stid *stid;
> > +     struct nfs4_stid *stid = NULL;
> >       struct nfs4_cpntf_state *cps;
> >       struct nfs4_client *clp = cstate->clp;
> >
> > @@ -1951,6 +1951,8 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> >                                       &stid);
> >       if (status)
> >               return status;
> > +     if (!stid)
> > +             return nfserr_bad_stateid;
> >
> >       cn->cpn_lease_time.tv_sec = nn->nfsd4_lease;
> >       cn->cpn_lease_time.tv_nsec = 0;
> > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> > index 69d576b19eb6..dc61a8adfcd4 100644
> > --- a/fs/nfsd/nfs4state.c
> > +++ b/fs/nfsd/nfs4state.c
> > @@ -7020,11 +7020,7 @@ nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
> >               *nfp = NULL;
> >
> >       if (ZERO_STATEID(stateid) || ONE_STATEID(stateid)) {
> > -             if (cstid)
> > -                     status = nfserr_bad_stateid;
> > -             else
> > -                     status = check_special_stateids(net, fhp, stateid,
> > -                                                                     flags);

This code was put in by Bruce in commit ("nfsd: fix crash on
COPY_NOTIFY with special stateid"). Its intentions were to make sure
that IF COPY_NOTFY was sent with a special state it, then the server
would produce an error (in this case bad_stateid). Only from
copy_notify do we call nfs4_preproces_stateid_op() with a non-null
cstid. This above logic is needed here as far as I can tell.

> > +             status = check_special_stateids(net, fhp, stateid, flags);
> >               goto done;
> >       }
> >
> > --
> > 2.43.0
> >
> >
>
> --
> Chuck Lever
Sagi Grimberg July 24, 2024, 9:43 p.m. UTC | #3
On 24/07/2024 22:12, Olga Kornievskaia wrote:
> On Wed, Jul 24, 2024 at 1:06 PM Chuck Lever <chuck.lever@oracle.com> wrote:
>> Adding Olga for her review and comments.
>>
>> On Wed, Jul 24, 2024 at 10:01:37AM -0700, Sagi Grimberg wrote:
>>> Move the stateid handling to nfsd4_copy_notify, if nfs4_preprocess_stateid_op
>>> did not produce an output stateid, error out.
>>>
>>> Copy notify specifically does not permit the use of special stateids,
>>> so enforce that outside generic stateid pre-processing.
> I dont see how this patch is accomplishing this. As far as I can tell
> (just by looking at the code without actually testing it) instead it
> does exactly the opposite.

I haven't tested this either, does pynfs have a test for it?

>
>>> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
>>> ---
>>>   fs/nfsd/nfs4proc.c  | 4 +++-
>>>   fs/nfsd/nfs4state.c | 6 +-----
>>>   2 files changed, 4 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
>>> index 46bd20fe5c0f..7b70309ad8fb 100644
>>> --- a/fs/nfsd/nfs4proc.c
>>> +++ b/fs/nfsd/nfs4proc.c
>>> @@ -1942,7 +1942,7 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>>>        struct nfsd4_copy_notify *cn = &u->copy_notify;
>>>        __be32 status;
>>>        struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
>>> -     struct nfs4_stid *stid;
>>> +     struct nfs4_stid *stid = NULL;
>>>        struct nfs4_cpntf_state *cps;
>>>        struct nfs4_client *clp = cstate->clp;
>>>
>>> @@ -1951,6 +1951,8 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>>>                                        &stid);
>>>        if (status)
>>>                return status;
>>> +     if (!stid)
>>> +             return nfserr_bad_stateid;
>>>
>>>        cn->cpn_lease_time.tv_sec = nn->nfsd4_lease;
>>>        cn->cpn_lease_time.tv_nsec = 0;
>>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
>>> index 69d576b19eb6..dc61a8adfcd4 100644
>>> --- a/fs/nfsd/nfs4state.c
>>> +++ b/fs/nfsd/nfs4state.c
>>> @@ -7020,11 +7020,7 @@ nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
>>>                *nfp = NULL;
>>>
>>>        if (ZERO_STATEID(stateid) || ONE_STATEID(stateid)) {
>>> -             if (cstid)
>>> -                     status = nfserr_bad_stateid;
>>> -             else
>>> -                     status = check_special_stateids(net, fhp, stateid,
>>> -                                                                     flags);
> This code was put in by Bruce in commit ("nfsd: fix crash on
> COPY_NOTIFY with special stateid"). Its intentions were to make sure
> that IF COPY_NOTFY was sent with a special state it, then the server
> would produce an error (in this case bad_stateid). Only from
> copy_notify do we call nfs4_preproces_stateid_op() with a non-null
> cstid. This above logic is needed here as far as I can tell.

So the purpose was now special stateids will not generate an output
stateid, which COPY_NOTIFY now checks, and fails locally in this case.

Maybe I'm missing something, but my assumption is that if a client
sends a COPY_NOTIFY with a special stateid, it will still error out with
bad stateid (due to the change in nfsd4_copy_notify...
Olga Kornievskaia July 25, 2024, 1:51 p.m. UTC | #4
On Wed, Jul 24, 2024 at 5:43 PM Sagi Grimberg <sagi@grimberg.me> wrote:
>
>
>
>
> On 24/07/2024 22:12, Olga Kornievskaia wrote:
> > On Wed, Jul 24, 2024 at 1:06 PM Chuck Lever <chuck.lever@oracle.com> wrote:
> >> Adding Olga for her review and comments.
> >>
> >> On Wed, Jul 24, 2024 at 10:01:37AM -0700, Sagi Grimberg wrote:
> >>> Move the stateid handling to nfsd4_copy_notify, if nfs4_preprocess_stateid_op
> >>> did not produce an output stateid, error out.
> >>>
> >>> Copy notify specifically does not permit the use of special stateids,
> >>> so enforce that outside generic stateid pre-processing.
> > I dont see how this patch is accomplishing this. As far as I can tell
> > (just by looking at the code without actually testing it) instead it
> > does exactly the opposite.
>
> I haven't tested this either, does pynfs have a test for it?
>
> >
> >>> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
> >>> ---
> >>>   fs/nfsd/nfs4proc.c  | 4 +++-
> >>>   fs/nfsd/nfs4state.c | 6 +-----
> >>>   2 files changed, 4 insertions(+), 6 deletions(-)
> >>>
> >>> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> >>> index 46bd20fe5c0f..7b70309ad8fb 100644
> >>> --- a/fs/nfsd/nfs4proc.c
> >>> +++ b/fs/nfsd/nfs4proc.c
> >>> @@ -1942,7 +1942,7 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> >>>        struct nfsd4_copy_notify *cn = &u->copy_notify;
> >>>        __be32 status;
> >>>        struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
> >>> -     struct nfs4_stid *stid;
> >>> +     struct nfs4_stid *stid = NULL;
> >>>        struct nfs4_cpntf_state *cps;
> >>>        struct nfs4_client *clp = cstate->clp;
> >>>
> >>> @@ -1951,6 +1951,8 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> >>>                                        &stid);
> >>>        if (status)
> >>>                return status;
> >>> +     if (!stid)
> >>> +             return nfserr_bad_stateid;
> >>>
> >>>        cn->cpn_lease_time.tv_sec = nn->nfsd4_lease;
> >>>        cn->cpn_lease_time.tv_nsec = 0;
> >>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> >>> index 69d576b19eb6..dc61a8adfcd4 100644
> >>> --- a/fs/nfsd/nfs4state.c
> >>> +++ b/fs/nfsd/nfs4state.c
> >>> @@ -7020,11 +7020,7 @@ nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
> >>>                *nfp = NULL;
> >>>
> >>>        if (ZERO_STATEID(stateid) || ONE_STATEID(stateid)) {
> >>> -             if (cstid)
> >>> -                     status = nfserr_bad_stateid;
> >>> -             else
> >>> -                     status = check_special_stateids(net, fhp, stateid,
> >>> -                                                                     flags);
> > This code was put in by Bruce in commit ("nfsd: fix crash on
> > COPY_NOTIFY with special stateid"). Its intentions were to make sure
> > that IF COPY_NOTFY was sent with a special state it, then the server
> > would produce an error (in this case bad_stateid). Only from
> > copy_notify do we call nfs4_preproces_stateid_op() with a non-null
> > cstid. This above logic is needed here as far as I can tell.
>
> So the purpose was now special stateids will not generate an output
> stateid, which COPY_NOTIFY now checks, and fails locally in this case.

Ok I see it now I do agree with the nfsd4_copy_notify() changes it
should be still guard against the use of special stateid.

> Maybe I'm missing something, but my assumption is that if a client
> sends a COPY_NOTIFY with a special stateid, it will still error out with
> bad stateid (due to the change in nfsd4_copy_notify...\

I agree now. Thank you for the explanation. Looks good.
Jeff Layton July 26, 2024, 1:23 p.m. UTC | #5
On Wed, 2024-07-24 at 10:01 -0700, Sagi Grimberg wrote:
> Move the stateid handling to nfsd4_copy_notify, if
> nfs4_preprocess_stateid_op
> did not produce an output stateid, error out.
> 
> Copy notify specifically does not permit the use of special stateids,
> so enforce that outside generic stateid pre-processing.
> 
> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
> ---
>  fs/nfsd/nfs4proc.c  | 4 +++-
>  fs/nfsd/nfs4state.c | 6 +-----
>  2 files changed, 4 insertions(+), 6 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> index 46bd20fe5c0f..7b70309ad8fb 100644
> --- a/fs/nfsd/nfs4proc.c
> +++ b/fs/nfsd/nfs4proc.c
> @@ -1942,7 +1942,7 @@ nfsd4_copy_notify(struct svc_rqst *rqstp,
> struct nfsd4_compound_state *cstate,
>  	struct nfsd4_copy_notify *cn = &u->copy_notify;
>  	__be32 status;
>  	struct nfsd_net *nn = net_generic(SVC_NET(rqstp),
> nfsd_net_id);
> -	struct nfs4_stid *stid;
> +	struct nfs4_stid *stid = NULL;
>  	struct nfs4_cpntf_state *cps;
>  	struct nfs4_client *clp = cstate->clp;
>  
> @@ -1951,6 +1951,8 @@ nfsd4_copy_notify(struct svc_rqst *rqstp,
> struct nfsd4_compound_state *cstate,
>  					&stid);
>  	if (status)
>  		return status;
> +	if (!stid)
> +		return nfserr_bad_stateid;
>  
>  	cn->cpn_lease_time.tv_sec = nn->nfsd4_lease;
>  	cn->cpn_lease_time.tv_nsec = 0;
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 69d576b19eb6..dc61a8adfcd4 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -7020,11 +7020,7 @@ nfs4_preprocess_stateid_op(struct svc_rqst
> *rqstp,
>  		*nfp = NULL;
>  
>  	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid)) {
> -		if (cstid)
> -			status = nfserr_bad_stateid;
> -		else
> -			status = check_special_stateids(net, fhp,
> stateid,
> -
> 									flags);
> +		status = check_special_stateids(net, fhp, stateid,
> flags);
>  		goto done;
>  	}
>  

Nice cleanup.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Chuck Lever July 26, 2024, 1:47 p.m. UTC | #6
On Thu, Jul 25, 2024 at 09:51:11AM -0400, Olga Kornievskaia wrote:
> On Wed, Jul 24, 2024 at 5:43 PM Sagi Grimberg <sagi@grimberg.me> wrote:
> >
> >
> >
> >
> > On 24/07/2024 22:12, Olga Kornievskaia wrote:
> > > On Wed, Jul 24, 2024 at 1:06 PM Chuck Lever <chuck.lever@oracle.com> wrote:
> > >> Adding Olga for her review and comments.
> > >>
> > >> On Wed, Jul 24, 2024 at 10:01:37AM -0700, Sagi Grimberg wrote:
> > >>> Move the stateid handling to nfsd4_copy_notify, if nfs4_preprocess_stateid_op
> > >>> did not produce an output stateid, error out.
> > >>>
> > >>> Copy notify specifically does not permit the use of special stateids,
> > >>> so enforce that outside generic stateid pre-processing.
> > > I dont see how this patch is accomplishing this. As far as I can tell
> > > (just by looking at the code without actually testing it) instead it
> > > does exactly the opposite.
> >
> > I haven't tested this either, does pynfs have a test for it?
> >
> > >
> > >>> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
> > >>> ---
> > >>>   fs/nfsd/nfs4proc.c  | 4 +++-
> > >>>   fs/nfsd/nfs4state.c | 6 +-----
> > >>>   2 files changed, 4 insertions(+), 6 deletions(-)
> > >>>
> > >>> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> > >>> index 46bd20fe5c0f..7b70309ad8fb 100644
> > >>> --- a/fs/nfsd/nfs4proc.c
> > >>> +++ b/fs/nfsd/nfs4proc.c
> > >>> @@ -1942,7 +1942,7 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> > >>>        struct nfsd4_copy_notify *cn = &u->copy_notify;
> > >>>        __be32 status;
> > >>>        struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
> > >>> -     struct nfs4_stid *stid;
> > >>> +     struct nfs4_stid *stid = NULL;
> > >>>        struct nfs4_cpntf_state *cps;
> > >>>        struct nfs4_client *clp = cstate->clp;
> > >>>
> > >>> @@ -1951,6 +1951,8 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> > >>>                                        &stid);
> > >>>        if (status)
> > >>>                return status;
> > >>> +     if (!stid)
> > >>> +             return nfserr_bad_stateid;
> > >>>
> > >>>        cn->cpn_lease_time.tv_sec = nn->nfsd4_lease;
> > >>>        cn->cpn_lease_time.tv_nsec = 0;
> > >>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> > >>> index 69d576b19eb6..dc61a8adfcd4 100644
> > >>> --- a/fs/nfsd/nfs4state.c
> > >>> +++ b/fs/nfsd/nfs4state.c
> > >>> @@ -7020,11 +7020,7 @@ nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
> > >>>                *nfp = NULL;
> > >>>
> > >>>        if (ZERO_STATEID(stateid) || ONE_STATEID(stateid)) {
> > >>> -             if (cstid)
> > >>> -                     status = nfserr_bad_stateid;
> > >>> -             else
> > >>> -                     status = check_special_stateids(net, fhp, stateid,
> > >>> -                                                                     flags);
> > > This code was put in by Bruce in commit ("nfsd: fix crash on
> > > COPY_NOTIFY with special stateid"). Its intentions were to make sure
> > > that IF COPY_NOTFY was sent with a special state it, then the server
> > > would produce an error (in this case bad_stateid). Only from
> > > copy_notify do we call nfs4_preproces_stateid_op() with a non-null
> > > cstid. This above logic is needed here as far as I can tell.
> >
> > So the purpose was now special stateids will not generate an output
> > stateid, which COPY_NOTIFY now checks, and fails locally in this case.
> 
> Ok I see it now I do agree with the nfsd4_copy_notify() changes it
> should be still guard against the use of special stateid.
> 
> > Maybe I'm missing something, but my assumption is that if a client
> > sends a COPY_NOTIFY with a special stateid, it will still error out with
> > bad stateid (due to the change in nfsd4_copy_notify...\
> 
> I agree now. Thank you for the explanation. Looks good.

Hi Olga, may I add a Reviewed-by: from you?
Olga Kornievskaia July 26, 2024, 2:07 p.m. UTC | #7
On Fri, Jul 26, 2024 at 9:47 AM Chuck Lever <chuck.lever@oracle.com> wrote:
>
> On Thu, Jul 25, 2024 at 09:51:11AM -0400, Olga Kornievskaia wrote:
> > On Wed, Jul 24, 2024 at 5:43 PM Sagi Grimberg <sagi@grimberg.me> wrote:
> > >
> > >
> > >
> > >
> > > On 24/07/2024 22:12, Olga Kornievskaia wrote:
> > > > On Wed, Jul 24, 2024 at 1:06 PM Chuck Lever <chuck.lever@oracle.com> wrote:
> > > >> Adding Olga for her review and comments.
> > > >>
> > > >> On Wed, Jul 24, 2024 at 10:01:37AM -0700, Sagi Grimberg wrote:
> > > >>> Move the stateid handling to nfsd4_copy_notify, if nfs4_preprocess_stateid_op
> > > >>> did not produce an output stateid, error out.
> > > >>>
> > > >>> Copy notify specifically does not permit the use of special stateids,
> > > >>> so enforce that outside generic stateid pre-processing.
> > > > I dont see how this patch is accomplishing this. As far as I can tell
> > > > (just by looking at the code without actually testing it) instead it
> > > > does exactly the opposite.
> > >
> > > I haven't tested this either, does pynfs have a test for it?
> > >
> > > >
> > > >>> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
> > > >>> ---
> > > >>>   fs/nfsd/nfs4proc.c  | 4 +++-
> > > >>>   fs/nfsd/nfs4state.c | 6 +-----
> > > >>>   2 files changed, 4 insertions(+), 6 deletions(-)
> > > >>>
> > > >>> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> > > >>> index 46bd20fe5c0f..7b70309ad8fb 100644
> > > >>> --- a/fs/nfsd/nfs4proc.c
> > > >>> +++ b/fs/nfsd/nfs4proc.c
> > > >>> @@ -1942,7 +1942,7 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> > > >>>        struct nfsd4_copy_notify *cn = &u->copy_notify;
> > > >>>        __be32 status;
> > > >>>        struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
> > > >>> -     struct nfs4_stid *stid;
> > > >>> +     struct nfs4_stid *stid = NULL;
> > > >>>        struct nfs4_cpntf_state *cps;
> > > >>>        struct nfs4_client *clp = cstate->clp;
> > > >>>
> > > >>> @@ -1951,6 +1951,8 @@ nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
> > > >>>                                        &stid);
> > > >>>        if (status)
> > > >>>                return status;
> > > >>> +     if (!stid)
> > > >>> +             return nfserr_bad_stateid;
> > > >>>
> > > >>>        cn->cpn_lease_time.tv_sec = nn->nfsd4_lease;
> > > >>>        cn->cpn_lease_time.tv_nsec = 0;
> > > >>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> > > >>> index 69d576b19eb6..dc61a8adfcd4 100644
> > > >>> --- a/fs/nfsd/nfs4state.c
> > > >>> +++ b/fs/nfsd/nfs4state.c
> > > >>> @@ -7020,11 +7020,7 @@ nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
> > > >>>                *nfp = NULL;
> > > >>>
> > > >>>        if (ZERO_STATEID(stateid) || ONE_STATEID(stateid)) {
> > > >>> -             if (cstid)
> > > >>> -                     status = nfserr_bad_stateid;
> > > >>> -             else
> > > >>> -                     status = check_special_stateids(net, fhp, stateid,
> > > >>> -                                                                     flags);
> > > > This code was put in by Bruce in commit ("nfsd: fix crash on
> > > > COPY_NOTIFY with special stateid"). Its intentions were to make sure
> > > > that IF COPY_NOTFY was sent with a special state it, then the server
> > > > would produce an error (in this case bad_stateid). Only from
> > > > copy_notify do we call nfs4_preproces_stateid_op() with a non-null
> > > > cstid. This above logic is needed here as far as I can tell.
> > >
> > > So the purpose was now special stateids will not generate an output
> > > stateid, which COPY_NOTIFY now checks, and fails locally in this case.
> >
> > Ok I see it now I do agree with the nfsd4_copy_notify() changes it
> > should be still guard against the use of special stateid.
> >
> > > Maybe I'm missing something, but my assumption is that if a client
> > > sends a COPY_NOTIFY with a special stateid, it will still error out with
> > > bad stateid (due to the change in nfsd4_copy_notify...\
> >
> > I agree now. Thank you for the explanation. Looks good.
>
> Hi Olga, may I add a Reviewed-by: from you?

Of course.

>
> --
> Chuck Lever
diff mbox series

Patch

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 46bd20fe5c0f..7b70309ad8fb 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1942,7 +1942,7 @@  nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	struct nfsd4_copy_notify *cn = &u->copy_notify;
 	__be32 status;
 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
-	struct nfs4_stid *stid;
+	struct nfs4_stid *stid = NULL;
 	struct nfs4_cpntf_state *cps;
 	struct nfs4_client *clp = cstate->clp;
 
@@ -1951,6 +1951,8 @@  nfsd4_copy_notify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 					&stid);
 	if (status)
 		return status;
+	if (!stid)
+		return nfserr_bad_stateid;
 
 	cn->cpn_lease_time.tv_sec = nn->nfsd4_lease;
 	cn->cpn_lease_time.tv_nsec = 0;
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 69d576b19eb6..dc61a8adfcd4 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -7020,11 +7020,7 @@  nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
 		*nfp = NULL;
 
 	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid)) {
-		if (cstid)
-			status = nfserr_bad_stateid;
-		else
-			status = check_special_stateids(net, fhp, stateid,
-									flags);
+		status = check_special_stateids(net, fhp, stateid, flags);
 		goto done;
 	}