> On Apr 8, 2019, at 11:50 AM, Olga Kornievskaia <aglo@xxxxxxxxx> wrote:
>
> On Mon, Apr 8, 2019 at 11:26 AM Olga Kornievskaia <aglo@xxxxxxxxx> wrote:
>>
>> On Mon, Apr 8, 2019 at 11:21 AM Olga Kornievskaia <aglo@xxxxxxxxx> wrote:
>>>
>>> On Mon, Apr 8, 2019 at 10:43 AM Chuck Lever <chuck.lever@xxxxxxxxxx> wrote:
>>>>
>>>>
>>>>
>>>>> On Apr 8, 2019, at 10:36 AM, Olga Kornievskaia <aglo@xxxxxxxxx> wrote:
>>>>>
>>>>> On Fri, Apr 5, 2019 at 3:42 PM Chuck Lever <chuck.lever@xxxxxxxxxx> wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>>> On Apr 5, 2019, at 3:27 PM, Olga Kornievskaia <aglo@xxxxxxxxx> wrote:
>>>>>>>
>>>>>>> On Fri, Apr 5, 2019 at 3:23 PM Chuck Lever <chuck.lever@xxxxxxxxxx> wrote:
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>> On Apr 5, 2019, at 3:17 PM, Olga Kornievskaia <aglo@xxxxxxxxx> wrote:
>>>>>>>>>
>>>>>>>>> On Fri, Apr 5, 2019 at 1:51 PM Chuck Lever <chuck.lever@xxxxxxxxxx> wrote:
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>> On Apr 5, 2019, at 1:36 PM, Olga Kornievskaia <aglo@xxxxxxxxx> wrote:
>>>>>>>>>>>
>>>>>>>>>>> Hi Chuck,
>>>>>>>>>>>
>>>>>>>>>>> This patch break ACLs. After applying this patch nfs4_getfacl fails
>>>>>>>>>>> (it fails within xdr and returns ENOTSUPP). Any ideas why?
>>>>>>>>>>
>>>>>>>>>> Possibly the macro that defines the maximum size of the reply
>>>>>>>>>> is incorrect.
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> This also breaks FS_LOCATION. I'm going to go on the limb here and say
>>>>>>>>> that it probably breaks whatever else it modified.
>>>>>>>>
>>>>>>>> It modifies READ, READDIR, and READLINK. Are those broken?
>>>>>>>
>>>>>>> I don't know how to test READLINK.. but I think READ/READDIR work OK
>>>>>>> otherwise folks would have noticed it (I gather ACL and FS_LOCATION
>>>>>>> testing doesn't happen frequently).
>>>>>>
>>>>>> I guess I don't have any NFSv4 ACL or FS_LOCATIONS regressions
>>>>>> tests in my automated unit tests.
>>>>>>
>>>>>>
>>>>>>>>> The question is: can't we just revert it??
>>>>>>>>
>>>>>>>> Why not "root cause" it first?
>>>>>>>
>>>>>>> I'm trying :-/ I was just fishing to see how important the change was.
>>>>>>
>>>>>> Try reverting just this hunk:
>>>>>
>>>>> That doesn't help. It seems to be this piece that's causing issues
>>>>> hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_rslack - 1
>>>>>
>>>>> With this there is an extra byte (in front) in the buffer when (ACL)
>>>>> operation is decoded.
>>>>
>>>> How do you know there isn't a latent bug in the getfacl decoder?
>>>
>>> I don't. All I know is that it passed tests before and now it doesn't.
>>
>> Also this bug will have to be in both getfacl and fs_location code.
>> What they both share is xd_enter_page() code that now with new
>> semantics makes the buffer point to the wrong place.
>>
>>>> How are you reproducing this issue? I can try it here later today.
>>>
>>> The issue was found running xfstest nfs/001. However, you don't need
>>> that: (1) mount (2) nfs4_getfacl <file>
>>>
>>> To understand a patch, does it fix a problem with READLINK or is the
>>> an optimization?
>
> So this "fixes" it but this don't look really good.
>
> diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
> index cfcabc3..f2a5553 100644
> --- a/fs/nfs/nfs4xdr.c
> +++ b/fs/nfs/nfs4xdr.c
>
> @@ -5280,6 +5280,7 @@ static int decode_getacl(struct xdr_stream *xdr,
> struct rpc_rqst *req,
> goto out;
> xdr_enter_page(xdr, xdr->buf->page_len);
> + xdr->p++;
>
> /* Calculate the offset of the page data */
> pg_offset = xdr->buf->head[0].iov_len;
> @@ -6949,6 +6950,7 @@ static int nfs4_xdr_dec_fs_locations(struct rpc_rqst *req,
> goto out;
> if (res->migration) {
> xdr_enter_page(xdr, PAGE_SIZE);
> + xdr->p++;
> status = decode_getfattr_generic(xdr,
> &res->fs_locations->fattr,
> NULL, res->fs_locations,
> @@ -6962,6 +6964,7 @@ static int nfs4_xdr_dec_fs_locations(struct rpc_rqst *req,
> if (status)
> goto out;
> xdr_enter_page(xdr, PAGE_SIZE);
> + xdr->p++;
> status = decode_getfattr_generic(xdr,
> &res->fs_locations->fattr,
> NULL, res->fs_locations,
Your workaround appears to advance xdr->p one quad into the first page in
the xdr_buf. We really want that XDR data item to fall right at offset 0
of that page.
I'm looking into it.
>>>>>> diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
>>>>>> index d0fa18d..6d9d5e2 100644
>>>>>> --- a/fs/nfs/nfs4xdr.c
>>>>>> +++ b/fs/nfs/nfs4xdr.c
>>>>>> @@ -284,14 +284,14 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req,
>>>>>> #define decode_delegreturn_maxsz (op_decode_hdr_maxsz)
>>>>>> #define encode_getacl_maxsz (encode_getattr_maxsz)
>>>>>> #define decode_getacl_maxsz (op_decode_hdr_maxsz + \
>>>>>> - nfs4_fattr_bitmap_maxsz + 1)
>>>>>> + nfs4_fattr_bitmap_maxsz + 1 + 1)
>>>>>> #define encode_setacl_maxsz (op_encode_hdr_maxsz + \
>>>>>> encode_stateid_maxsz + 3)
>>>>>> #define decode_setacl_maxsz (decode_setattr_maxsz)
>>>>>> #define encode_fs_locations_maxsz \
>>>>>> (encode_getattr_maxsz)
>>>>>> #define decode_fs_locations_maxsz \
>>>>>> - (0)
>>>>>> + (1)
>>>>>> #define encode_secinfo_maxsz (op_encode_hdr_maxsz + nfs4_name_maxsz)
>>>>>> #define decode_secinfo_maxsz (op_decode_hdr_maxsz + 1 + ((NFS_MAX_SECFLAVORS * (16 + GSS_OID_MAX_LEN)) / 4))
>>>>>>
>>>>>>
>>>>>>>>>>> On Mon, Feb 11, 2019 at 11:25 AM Chuck Lever <chuck.lever@xxxxxxxxxx> wrote:
>>>>>>>>>>>>
>>>>>>>>>>>> Certain NFS results (eg. READLINK) might expect a data payload that
>>>>>>>>>>>> is not an exact multiple of 4 bytes. In this case, XDR encoding
>>>>>>>>>>>> is required to pad that payload so its length on the wire is a
>>>>>>>>>>>> multiple of 4 bytes. The constants that define the maximum size of
>>>>>>>>>>>> each NFS result do not appear to account for this extra word.
>>>>>>>>>>>>
>>>>>>>>>>>> In each case where the data payload is to be received into pages:
>>>>>>>>>>>>
>>>>>>>>>>>> - 1 word is added to the size of the receive buffer allocated by
>>>>>>>>>>>> call_allocate
>>>>>>>>>>>>
>>>>>>>>>>>> - rpc_inline_rcv_pages subtracts 1 word from @hdrsize so that the
>>>>>>>>>>>> extra buffer space falls into the rcv_buf's tail iovec
>>>>>>>>>>>>
>>>>>>>>>>>> - If buf->pagelen is word-aligned, an XDR pad is not needed and
>>>>>>>>>>>> is thus removed from the tail
>>>>>>>>>>>>
>>>>>>>>>>>> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
>>>>>>>>>>>> ---
>>>>>>>>>>>> fs/nfs/nfs2xdr.c | 6 +++---
>>>>>>>>>>>> fs/nfs/nfs3xdr.c | 10 +++++-----
>>>>>>>>>>>> fs/nfs/nfs4xdr.c | 15 ++++++++-------
>>>>>>>>>>>> net/sunrpc/clnt.c | 6 +++++-
>>>>>>>>>>>> net/sunrpc/xdr.c | 2 ++
>>>>>>>>>>>> 5 files changed, 23 insertions(+), 16 deletions(-)
>>>>>>>>>>>>
>>>>>>>>>>>> diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c
>>>>>>>>>>>> index 1dcd0fe..a7ed29d 100644
>>>>>>>>>>>> --- a/fs/nfs/nfs2xdr.c
>>>>>>>>>>>> +++ b/fs/nfs/nfs2xdr.c
>>>>>>>>>>>> @@ -56,11 +56,11 @@
>>>>>>>>>>>>
>>>>>>>>>>>> #define NFS_attrstat_sz (1+NFS_fattr_sz)
>>>>>>>>>>>> #define NFS_diropres_sz (1+NFS_fhandle_sz+NFS_fattr_sz)
>>>>>>>>>>>> -#define NFS_readlinkres_sz (2)
>>>>>>>>>>>> -#define NFS_readres_sz (1+NFS_fattr_sz+1)
>>>>>>>>>>>> +#define NFS_readlinkres_sz (2+1)
>>>>>>>>>>>> +#define NFS_readres_sz (1+NFS_fattr_sz+1+1)
>>>>>>>>>>>> #define NFS_writeres_sz (NFS_attrstat_sz)
>>>>>>>>>>>> #define NFS_stat_sz (1)
>>>>>>>>>>>> -#define NFS_readdirres_sz (1)
>>>>>>>>>>>> +#define NFS_readdirres_sz (1+1)
>>>>>>>>>>>> #define NFS_statfsres_sz (1+NFS_info_sz)
>>>>>>>>>>>>
>>>>>>>>>>>> static int nfs_stat_to_errno(enum nfs_stat);
>>>>>>>>>>>> diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c
>>>>>>>>>>>> index a54dcf4..110358f 100644
>>>>>>>>>>>> --- a/fs/nfs/nfs3xdr.c
>>>>>>>>>>>> +++ b/fs/nfs/nfs3xdr.c
>>>>>>>>>>>> @@ -69,13 +69,13 @@
>>>>>>>>>>>> #define NFS3_removeres_sz (NFS3_setattrres_sz)
>>>>>>>>>>>> #define NFS3_lookupres_sz (1+NFS3_fh_sz+(2 * NFS3_post_op_attr_sz))
>>>>>>>>>>>> #define NFS3_accessres_sz (1+NFS3_post_op_attr_sz+1)
>>>>>>>>>>>> -#define NFS3_readlinkres_sz (1+NFS3_post_op_attr_sz+1)
>>>>>>>>>>>> -#define NFS3_readres_sz (1+NFS3_post_op_attr_sz+3)
>>>>>>>>>>>> +#define NFS3_readlinkres_sz (1+NFS3_post_op_attr_sz+1+1)
>>>>>>>>>>>> +#define NFS3_readres_sz (1+NFS3_post_op_attr_sz+3+1)
>>>>>>>>>>>> #define NFS3_writeres_sz (1+NFS3_wcc_data_sz+4)
>>>>>>>>>>>> #define NFS3_createres_sz (1+NFS3_fh_sz+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
>>>>>>>>>>>> #define NFS3_renameres_sz (1+(2 * NFS3_wcc_data_sz))
>>>>>>>>>>>> #define NFS3_linkres_sz (1+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
>>>>>>>>>>>> -#define NFS3_readdirres_sz (1+NFS3_post_op_attr_sz+2)
>>>>>>>>>>>> +#define NFS3_readdirres_sz (1+NFS3_post_op_attr_sz+2+1)
>>>>>>>>>>>> #define NFS3_fsstatres_sz (1+NFS3_post_op_attr_sz+13)
>>>>>>>>>>>> #define NFS3_fsinfores_sz (1+NFS3_post_op_attr_sz+12)
>>>>>>>>>>>> #define NFS3_pathconfres_sz (1+NFS3_post_op_attr_sz+6)
>>>>>>>>>>>> @@ -85,7 +85,7 @@
>>>>>>>>>>>> #define ACL3_setaclargs_sz (NFS3_fh_sz+1+ \
>>>>>>>>>>>> XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
>>>>>>>>>>>> #define ACL3_getaclres_sz (1+NFS3_post_op_attr_sz+1+ \
>>>>>>>>>>>> - XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
>>>>>>>>>>>> + XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE)+1)
>>>>>>>>>>>> #define ACL3_setaclres_sz (1+NFS3_post_op_attr_sz)
>>>>>>>>>>>>
>>>>>>>>>>>> static int nfs3_stat_to_errno(enum nfs_stat);
>>>>>>>>>>>> @@ -1629,7 +1629,7 @@ static int nfs3_xdr_dec_read3res(struct rpc_rqst *req, struct xdr_stream *xdr,
>>>>>>>>>>>> result->op_status = status;
>>>>>>>>>>>> if (status != NFS3_OK)
>>>>>>>>>>>> goto out_status;
>>>>>>>>>>>> - result->replen = 3 + ((xdr_stream_pos(xdr) - pos) >> 2);
>>>>>>>>>>>> + result->replen = 4 + ((xdr_stream_pos(xdr) - pos) >> 2);
>>>>>>>>>>>> error = decode_read3resok(xdr, result);
>>>>>>>>>>>> out:
>>>>>>>>>>>> return error;
>>>>>>>>>>>> diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
>>>>>>>>>>>> index d0fa18d..6d9d5e2 100644
>>>>>>>>>>>> --- a/fs/nfs/nfs4xdr.c
>>>>>>>>>>>> +++ b/fs/nfs/nfs4xdr.c
>>>>>>>>>>>> @@ -215,14 +215,14 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req,
>>>>>>>>>>>> nfs4_fattr_bitmap_maxsz)
>>>>>>>>>>>> #define encode_read_maxsz (op_encode_hdr_maxsz + \
>>>>>>>>>>>> encode_stateid_maxsz + 3)
>>>>>>>>>>>> -#define decode_read_maxsz (op_decode_hdr_maxsz + 2)
>>>>>>>>>>>> +#define decode_read_maxsz (op_decode_hdr_maxsz + 2 + 1)
>>>>>>>>>>>> #define encode_readdir_maxsz (op_encode_hdr_maxsz + \
>>>>>>>>>>>> 2 + encode_verifier_maxsz + 5 + \
>>>>>>>>>>>> nfs4_label_maxsz)
>>>>>>>>>>>> #define decode_readdir_maxsz (op_decode_hdr_maxsz + \
>>>>>>>>>>>> - decode_verifier_maxsz)
>>>>>>>>>>>> + decode_verifier_maxsz + 1)
>>>>>>>>>>>> #define encode_readlink_maxsz (op_encode_hdr_maxsz)
>>>>>>>>>>>> -#define decode_readlink_maxsz (op_decode_hdr_maxsz + 1)
>>>>>>>>>>>> +#define decode_readlink_maxsz (op_decode_hdr_maxsz + 1 + 1)
>>>>>>>>>>>> #define encode_write_maxsz (op_encode_hdr_maxsz + \
>>>>>>>>>>>> encode_stateid_maxsz + 4)
>>>>>>>>>>>> #define decode_write_maxsz (op_decode_hdr_maxsz + \
>>>>>>>>>>>> @@ -284,14 +284,14 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req,
>>>>>>>>>>>> #define decode_delegreturn_maxsz (op_decode_hdr_maxsz)
>>>>>>>>>>>> #define encode_getacl_maxsz (encode_getattr_maxsz)
>>>>>>>>>>>> #define decode_getacl_maxsz (op_decode_hdr_maxsz + \
>>>>>>>>>>>> - nfs4_fattr_bitmap_maxsz + 1)
>>>>>>>>>>>> + nfs4_fattr_bitmap_maxsz + 1 + 1)
>>>>>>>>>>>> #define encode_setacl_maxsz (op_encode_hdr_maxsz + \
>>>>>>>>>>>> encode_stateid_maxsz + 3)
>>>>>>>>>>>> #define decode_setacl_maxsz (decode_setattr_maxsz)
>>>>>>>>>>>> #define encode_fs_locations_maxsz \
>>>>>>>>>>>> (encode_getattr_maxsz)
>>>>>>>>>>>> #define decode_fs_locations_maxsz \
>>>>>>>>>>>> - (0)
>>>>>>>>>>>> + (1)
>>>>>>>>>>>> #define encode_secinfo_maxsz (op_encode_hdr_maxsz + nfs4_name_maxsz)
>>>>>>>>>>>> #define decode_secinfo_maxsz (op_decode_hdr_maxsz + 1 + ((NFS_MAX_SECFLAVORS * (16 + GSS_OID_MAX_LEN)) / 4))
>>>>>>>>>>>>
>>>>>>>>>>>> @@ -392,12 +392,13 @@ static int decode_layoutget(struct xdr_stream *xdr, struct rpc_rqst *req,
>>>>>>>>>>>> 1 /* opaque devaddr4 length */ + \
>>>>>>>>>>>> /* devaddr4 payload is read into page */ \
>>>>>>>>>>>> 1 /* notification bitmap length */ + \
>>>>>>>>>>>> - 1 /* notification bitmap, word 0 */)
>>>>>>>>>>>> + 1 /* notification bitmap, word 0 */ + \
>>>>>>>>>>>> + 1 /* possible XDR padding */)
>>>>>>>>>>>> #define encode_layoutget_maxsz (op_encode_hdr_maxsz + 10 + \
>>>>>>>>>>>> encode_stateid_maxsz)
>>>>>>>>>>>> #define decode_layoutget_maxsz (op_decode_hdr_maxsz + 8 + \
>>>>>>>>>>>> decode_stateid_maxsz + \
>>>>>>>>>>>> - XDR_QUADLEN(PNFS_LAYOUT_MAXSIZE))
>>>>>>>>>>>> + XDR_QUADLEN(PNFS_LAYOUT_MAXSIZE) + 1)
>>>>>>>>>>>> #define encode_layoutcommit_maxsz (op_encode_hdr_maxsz + \
>>>>>>>>>>>> 2 /* offset */ + \
>>>>>>>>>>>> 2 /* length */ + \
>>>>>>>>>>>> diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
>>>>>>>>>>>> index f780605..4ea38b0 100644
>>>>>>>>>>>> --- a/net/sunrpc/clnt.c
>>>>>>>>>>>> +++ b/net/sunrpc/clnt.c
>>>>>>>>>>>> @@ -1177,7 +1177,11 @@ void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
>>>>>>>>>>>> unsigned int base, unsigned int len,
>>>>>>>>>>>> unsigned int hdrsize)
>>>>>>>>>>>> {
>>>>>>>>>>>> - hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_rslack;
>>>>>>>>>>>> + /* Subtract one to force an extra word of buffer space for the
>>>>>>>>>>>> + * payload's XDR pad to fall into the rcv_buf's tail iovec.
>>>>>>>>>>>> + */
>>>>>>>>>>>> + hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_rslack - 1;
>>>>>>>>>>>> +
>>>>>>>>>>>> xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
>>>>>>>>>>>> trace_rpc_reply_pages(req);
>>>>>>>>>>>> }
>>>>>>>>>>>> diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
>>>>>>>>>>>> index 7cca515..aa8177d 100644
>>>>>>>>>>>> --- a/net/sunrpc/xdr.c
>>>>>>>>>>>> +++ b/net/sunrpc/xdr.c
>>>>>>>>>>>> @@ -189,6 +189,8 @@ __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int nbytes)
>>>>>>>>>>>>
>>>>>>>>>>>> tail->iov_base = buf + offset;
>>>>>>>>>>>> tail->iov_len = buflen - offset;
>>>>>>>>>>>> + if ((xdr->page_len & 3) == 0)
>>>>>>>>>>>> + tail->iov_len -= sizeof(__be32);
>>>>>>>>>>>>
>>>>>>>>>>>> xdr->buflen += len;
>>>>>>>>>>>> }
>>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> --
>>>>>>>>>> Chuck Lever
>>>>>>>>
>>>>>>>> --
>>>>>>>> Chuck Lever
>>>>>>
>>>>>> --
>>>>>> Chuck Lever
>>>>
>>>> --
>>>> Chuck Lever
--
Chuck Lever
