[Virtio-fs] [PATCH] virtiofsd: fix double fuse_mbuf_iter_advance when do_removemapping

[Virtio-fs] [PATCH] virtiofsd: fix double fuse_mbuf_iter_advance when do_removemapping

[Catherine Ho]

Commit 8e92b1fc98f7 ("DAX: virtiofsd: make FUSE_REMOVEMAPPING support
multiple entries") forgot to remove one fuse_mbuf_iter_advance in
do_removemapping.

Without this patch, virtiofsd will report:
[ID: 00000123] do_removemapping: invalid in, expected 1 * 16, has 60 - 60
[ID: 00000123]    unique: 232, error: -22 (Invalid argument), outsize: 16

Fixes: 8e92b1fc98f7 ("DAX: virtiofsd: make FUSE_REMOVEMAPPING support multiple entries")
Cc: Peng Tao <tao.peng@linux.alibaba.com>
Signed-off-by: Catherine Ho <catherine.hecx@gmail.com>
---
 contrib/virtiofsd/fuse_lowlevel.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/contrib/virtiofsd/fuse_lowlevel.c b/contrib/virtiofsd/fuse_lowlevel.c
index bde66c72c3..752e7d97b9 100644
--- a/contrib/virtiofsd/fuse_lowlevel.c
+++ b/contrib/virtiofsd/fuse_lowlevel.c
@@ -1894,14 +1894,6 @@ static void do_removemapping(fuse_req_t req, fuse_ino_t nodeid,
 		return;
 	}
 
-	one = fuse_mbuf_iter_advance(iter, sizeof(*one));
-	if (!one) {
-		fuse_log(FUSE_LOG_ERR, "do_removemapping: invalid in, expected %d * %ld, has %ld - %ld\n",
-			 arg->count, sizeof(*one), iter->size, iter->pos);
-		fuse_reply_err(req, EINVAL);
-		return;
-	}
-
 	if (req->se->op.removemapping)
 		req->se->op.removemapping(req, req->se, nodeid, arg->count, one);
 	else
-- 
2.17.1

Re: [Virtio-fs] [PATCH] virtiofsd: fix double fuse_mbuf_iter_advance when do_removemapping

[Peng Tao]

On 2019/12/5 17:01, Catherine Ho wrote:
> Commit 8e92b1fc98f7 ("DAX: virtiofsd: make FUSE_REMOVEMAPPING support
> multiple entries") forgot to remove one fuse_mbuf_iter_advance in
> do_removemapping.
No, we do need to advance twice. One for fuse_removemapping_in, another 
for an array of fuse_removemapping_one.

> 
> Without this patch, virtiofsd will report:
> [ID: 00000123] do_removemapping: invalid in, expected 1 * 16, has 60 - 60
> [ID: 00000123]    unique: 232, error: -22 (Invalid argument), outsize: 16
> 
What kernel version are you using? It appears that the remove mapping 
request does not container a proper fuse_removemapping_one struct.

> Fixes: 8e92b1fc98f7 ("DAX: virtiofsd: make FUSE_REMOVEMAPPING support multiple entries")
> Cc: Peng Tao <tao.peng@linux.alibaba.com>
> Signed-off-by: Catherine Ho <catherine.hecx@gmail.com>
> ---
>   contrib/virtiofsd/fuse_lowlevel.c | 8 --------
>   1 file changed, 8 deletions(-)
> 
> diff --git a/contrib/virtiofsd/fuse_lowlevel.c b/contrib/virtiofsd/fuse_lowlevel.c
> index bde66c72c3..752e7d97b9 100644
> --- a/contrib/virtiofsd/fuse_lowlevel.c
> +++ b/contrib/virtiofsd/fuse_lowlevel.c
> @@ -1894,14 +1894,6 @@ static void do_removemapping(fuse_req_t req, fuse_ino_t nodeid,
>   		return;
>   	}
>   
> -	one = fuse_mbuf_iter_advance(iter, sizeof(*one));
> -	if (!one) {
> -		fuse_log(FUSE_LOG_ERR, "do_removemapping: invalid in, expected %d * %ld, has %ld - %ld\n",
> -			 arg->count, sizeof(*one), iter->size, iter->pos);
> -		fuse_reply_err(req, EINVAL);
> -		return;
> -	}
> -
>   	if (req->se->op.removemapping)
>   		req->se->op.removemapping(req, req->se, nodeid, arg->count, one);
The patch is wrong itself, as `one` is not assigned here.

Cheers,
Tao

-- 
Into something rich and strange.

Re: [Virtio-fs] [PATCH] virtiofsd: fix double fuse_mbuf_iter_advance when do_removemapping

[Catherine Ho]

Hi Peng

On Thu, 5 Dec 2019 at 17:19, Peng Tao <tao.peng@linux.alibaba.com> wrote:
>
> On 2019/12/5 17:01, Catherine Ho wrote:
> > Commit 8e92b1fc98f7 ("DAX: virtiofsd: make FUSE_REMOVEMAPPING support
> > multiple entries") forgot to remove one fuse_mbuf_iter_advance in
> > do_removemapping.
> No, we do need to advance twice. One for fuse_removemapping_in, another
> for an array of fuse_removemapping_one.
>
But seems it advances for 3 times. What I mean is the 2nd advance of *one*
is pointless.
Please see [1] [2]
[1]https://gitlab.com/virtio-fs/qemu/blob/virtio-fs-dev/contrib/virtiofsd/fuse_lowlevel.c#L1888
[2]https://gitlab.com/virtio-fs/qemu/blob/virtio-fs-dev/contrib/virtiofsd/fuse_lowlevel.c#L1896

Best Regards
Catherine
> >
> > Without this patch, virtiofsd will report:
> > [ID: 00000123] do_removemapping: invalid in, expected 1 * 16, has 60 - 60
> > [ID: 00000123]    unique: 232, error: -22 (Invalid argument), outsize: 16
> >
> What kernel version are you using? It appears that the remove mapping
> request does not container a proper fuse_removemapping_one struct.
>
> > Fixes: 8e92b1fc98f7 ("DAX: virtiofsd: make FUSE_REMOVEMAPPING support multiple entries")
> > Cc: Peng Tao <tao.peng@linux.alibaba.com>
> > Signed-off-by: Catherine Ho <catherine.hecx@gmail.com>
> > ---
> >   contrib/virtiofsd/fuse_lowlevel.c | 8 --------
> >   1 file changed, 8 deletions(-)
> >
> > diff --git a/contrib/virtiofsd/fuse_lowlevel.c b/contrib/virtiofsd/fuse_lowlevel.c
> > index bde66c72c3..752e7d97b9 100644
> > --- a/contrib/virtiofsd/fuse_lowlevel.c
> > +++ b/contrib/virtiofsd/fuse_lowlevel.c
> > @@ -1894,14 +1894,6 @@ static void do_removemapping(fuse_req_t req, fuse_ino_t nodeid,
> >               return;
> >       }
> >
> > -     one = fuse_mbuf_iter_advance(iter, sizeof(*one));
> > -     if (!one) {
> > -             fuse_log(FUSE_LOG_ERR, "do_removemapping: invalid in, expected %d * %ld, has %ld - %ld\n",
> > -                      arg->count, sizeof(*one), iter->size, iter->pos);
> > -             fuse_reply_err(req, EINVAL);
> > -             return;
> > -     }
> > -
> >       if (req->se->op.removemapping)
> >               req->se->op.removemapping(req, req->se, nodeid, arg->count, one);
> The patch is wrong itself, as `one` is not assigned here.
>

Re: [Virtio-fs] [PATCH] virtiofsd: fix double fuse_mbuf_iter_advance when do_removemapping

[Peng Tao]

On 2019/12/5 17:34, Catherine Ho wrote:
> Hi Peng
> 
> On Thu, 5 Dec 2019 at 17:19, Peng Tao <tao.peng@linux.alibaba.com> wrote:
>>
>> On 2019/12/5 17:01, Catherine Ho wrote:
>>> Commit 8e92b1fc98f7 ("DAX: virtiofsd: make FUSE_REMOVEMAPPING support
>>> multiple entries") forgot to remove one fuse_mbuf_iter_advance in
>>> do_removemapping.
>> No, we do need to advance twice. One for fuse_removemapping_in, another
>> for an array of fuse_removemapping_one.
>>
> But seems it advances for 3 times. What I mean is the 2nd advance of *one*
> is pointless.
> Please see [1] [2]
> [1]https://gitlab.com/virtio-fs/qemu/blob/virtio-fs-dev/contrib/virtiofsd/fuse_lowlevel.c#L1888
> [2]https://gitlab.com/virtio-fs/qemu/blob/virtio-fs-dev/contrib/virtiofsd/fuse_lowlevel.c#L1896
> 
oops, that does look like a merge hunk. I don't have it in my local 
branch. After pulling the latest code I can see it too. And there was a 
branch reset at some point.

 From https://gitlab.com/virtio-fs/qemu
  + 42db960...5a356e6 virtio-fs-dev -> virtiofs/virtio-fs-dev  (forced 
update)

Now your patch looks good to me. Thanks!

Cheers,
Tao
> Best Regards
> Catherine
>>>
>>> Without this patch, virtiofsd will report:
>>> [ID: 00000123] do_removemapping: invalid in, expected 1 * 16, has 60 - 60
>>> [ID: 00000123]    unique: 232, error: -22 (Invalid argument), outsize: 16
>>>
>> What kernel version are you using? It appears that the remove mapping
>> request does not container a proper fuse_removemapping_one struct.
>>
>>> Fixes: 8e92b1fc98f7 ("DAX: virtiofsd: make FUSE_REMOVEMAPPING support multiple entries")
>>> Cc: Peng Tao <tao.peng@linux.alibaba.com>
>>> Signed-off-by: Catherine Ho <catherine.hecx@gmail.com>
Reviewed-by: Peng Tao <tao.peng@linux.alibaba.com>

>>> ---
>>>    contrib/virtiofsd/fuse_lowlevel.c | 8 --------
>>>    1 file changed, 8 deletions(-)
>>>
>>> diff --git a/contrib/virtiofsd/fuse_lowlevel.c b/contrib/virtiofsd/fuse_lowlevel.c
>>> index bde66c72c3..752e7d97b9 100644
>>> --- a/contrib/virtiofsd/fuse_lowlevel.c
>>> +++ b/contrib/virtiofsd/fuse_lowlevel.c
>>> @@ -1894,14 +1894,6 @@ static void do_removemapping(fuse_req_t req, fuse_ino_t nodeid,
>>>                return;
>>>        }
>>>
>>> -     one = fuse_mbuf_iter_advance(iter, sizeof(*one));
>>> -     if (!one) {
>>> -             fuse_log(FUSE_LOG_ERR, "do_removemapping: invalid in, expected %d * %ld, has %ld - %ld\n",
>>> -                      arg->count, sizeof(*one), iter->size, iter->pos);
>>> -             fuse_reply_err(req, EINVAL);
>>> -             return;
>>> -     }
>>> -
>>>        if (req->se->op.removemapping)
>>>                req->se->op.removemapping(req, req->se, nodeid, arg->count, one);
>> The patch is wrong itself, as `one` is not assigned here.
>>

-- 
Into something rich and strange.

Re: [Virtio-fs] [PATCH] virtiofsd: fix double fuse_mbuf_iter_advance when do_removemapping

[Dr. David Alan Gilbert]

* Peng Tao (tao.peng@linux.alibaba.com) wrote:
> 
> 
> On 2019/12/5 17:34, Catherine Ho wrote:
> > Hi Peng
> > 
> > On Thu, 5 Dec 2019 at 17:19, Peng Tao <tao.peng@linux.alibaba.com> wrote:
> > > 
> > > On 2019/12/5 17:01, Catherine Ho wrote:
> > > > Commit 8e92b1fc98f7 ("DAX: virtiofsd: make FUSE_REMOVEMAPPING support
> > > > multiple entries") forgot to remove one fuse_mbuf_iter_advance in
> > > > do_removemapping.
> > > No, we do need to advance twice. One for fuse_removemapping_in, another
> > > for an array of fuse_removemapping_one.
> > > 
> > But seems it advances for 3 times. What I mean is the 2nd advance of *one*
> > is pointless.
> > Please see [1] [2]
> > [1]https://gitlab.com/virtio-fs/qemu/blob/virtio-fs-dev/contrib/virtiofsd/fuse_lowlevel.c#L1888
> > [2]https://gitlab.com/virtio-fs/qemu/blob/virtio-fs-dev/contrib/virtiofsd/fuse_lowlevel.c#L1896
> > 
> oops, that does look like a merge hunk. I don't have it in my local branch.
> After pulling the latest code I can see it too. And there was a branch reset
> at some point.
> 
> From https://gitlab.com/virtio-fs/qemu
>  + 42db960...5a356e6 virtio-fs-dev -> virtiofs/virtio-fs-dev  (forced
> update)
> 
> Now your patch looks good to me. Thanks!

That's probably my screwup sometime during a rebase.

Catherine: Thanks; I'll find the right place to merge your fix in.

Dave

> Cheers,
> Tao
> > Best Regards
> > Catherine
> > > > 
> > > > Without this patch, virtiofsd will report:
> > > > [ID: 00000123] do_removemapping: invalid in, expected 1 * 16, has 60 - 60
> > > > [ID: 00000123]    unique: 232, error: -22 (Invalid argument), outsize: 16
> > > > 
> > > What kernel version are you using? It appears that the remove mapping
> > > request does not container a proper fuse_removemapping_one struct.
> > > 
> > > > Fixes: 8e92b1fc98f7 ("DAX: virtiofsd: make FUSE_REMOVEMAPPING support multiple entries")
> > > > Cc: Peng Tao <tao.peng@linux.alibaba.com>
> > > > Signed-off-by: Catherine Ho <catherine.hecx@gmail.com>
> Reviewed-by: Peng Tao <tao.peng@linux.alibaba.com>
> 
> > > > ---
> > > >    contrib/virtiofsd/fuse_lowlevel.c | 8 --------
> > > >    1 file changed, 8 deletions(-)
> > > > 
> > > > diff --git a/contrib/virtiofsd/fuse_lowlevel.c b/contrib/virtiofsd/fuse_lowlevel.c
> > > > index bde66c72c3..752e7d97b9 100644
> > > > --- a/contrib/virtiofsd/fuse_lowlevel.c
> > > > +++ b/contrib/virtiofsd/fuse_lowlevel.c
> > > > @@ -1894,14 +1894,6 @@ static void do_removemapping(fuse_req_t req, fuse_ino_t nodeid,
> > > >                return;
> > > >        }
> > > > 
> > > > -     one = fuse_mbuf_iter_advance(iter, sizeof(*one));
> > > > -     if (!one) {
> > > > -             fuse_log(FUSE_LOG_ERR, "do_removemapping: invalid in, expected %d * %ld, has %ld - %ld\n",
> > > > -                      arg->count, sizeof(*one), iter->size, iter->pos);
> > > > -             fuse_reply_err(req, EINVAL);
> > > > -             return;
> > > > -     }
> > > > -
> > > >        if (req->se->op.removemapping)
> > > >                req->se->op.removemapping(req, req->se, nodeid, arg->count, one);
> > > The patch is wrong itself, as `one` is not assigned here.
> > > 
> 
> -- 
> Into something rich and strange.
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK