xdr_buf_to_bvec() returns a slot count even when the caller's bvec
budget is exhausted partway through the xdr_buf. Callers feed that
count into iov_iter_bvec() and continue as if the conversion had
succeeded, silently sending or writing fewer bytes than the data
length declares. For an NFS WRITE the server reports the truncated
transfer to the client as full success.
The overflow represents an internal invariant violation: a higher
layer reserved a bvec budget too small for the xdr_buf it then
asked the encoder to convert. That is a server-side fault, not a
media I/O failure and not a malformed client argument.
Change xdr_buf_to_bvec() to return a signed int and have the
overflow label return -ESERVERFAULT. Update the three callers to
detect the negative return and fail the request: nfsd_vfs_write()
folds the error into host_err, which nfserrno() translates to
nfserr_serverfault for the WRITE reply; svc_udp_sendto() and
svc_tcp_sendmsg() propagate the error out of the send path.
Reported-by: Chris Mason <clm@meta.com>
Fixes: 2eb2b93581 ("SUNRPC: Convert svc_tcp_sendmsg to use bio_vecs directly")
Cc: stable@vger.kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
xdr_buf_to_bvec() writes a bio_vec into the caller's array before
testing whether that slot is in range, and the head branch performs
the store with no check at all. When the caller's budget is exactly
used up, the next store lands one element past the end of the array.
The overflow label returns count - 1, which masks the surplus store
but cannot undo it.
rq_bvec, the array passed by nfsd_vfs_write(), is allocated to
exactly rq_maxpages entries with no slack. The OOB store can land in
adjacent slab memory; the bv_len and bv_offset fields written there
are derived from client-supplied RPC payload sizes.
Move the in-range check ahead of the store in the head, page-loop,
and tail branches. With the check at the top of each sequence, count
is incremented only after a successful store, so the overflow label
can return count directly.
Reported-by: Chris Mason <clm@meta.com>
Fixes: 2eb2b93581 ("SUNRPC: Convert svc_tcp_sendmsg to use bio_vecs directly")
Cc: stable@vger.kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
With all per-message crypto operations routed through crypto/krb5,
a substantial body of code in rpcsec_gss_krb5 has no remaining
callers. The internal key derivation functions (krb5_derive_key_v2,
krb5_kdf_hmac_sha2, krb5_kdf_feedback_cmac) and the low-level
crypto primitives (krb5_encrypt, gss_krb5_checksum, krb5_cbc_cts_
encrypt/decrypt, krb5_etm_checksum) are unreachable because their
only call sites were the per-enctype function pointers removed in
previous patches. Delete gss_krb5_keys.c entirely and strip the
dead functions from gss_krb5_crypto.c.
The KUnit test suite in gss_krb5_test.c exercised exactly these
internal functions: RFC 3961 n-fold, RFC 3962 key derivation,
RFC 6803 Camellia key derivation, and RFC 8009 AES-SHA2 key
derivation, plus encryption self-tests that drove the now-removed
encrypt routines. The corresponding test coverage is provided by
the crypto/krb5 selftests in crypto/krb5/selftest.c. Remove the
test file, the RPCSEC_GSS_KRB5_KUNIT_TEST Kconfig symbol, the
.kunitconfig, and all VISIBLE_IF_KUNIT / EXPORT_SYMBOL_IF_KUNIT
annotations.
xdr_process_buf() walked xdr_buf segments through a per-segment
callback and existed solely for the crypto routines in
gss_krb5_crypto.c. With that file removed, xdr_process_buf()
has no remaining callers. Its successor, xdr_buf_to_sg(),
populates a scatterlist directly from an xdr_buf byte range
and was introduced earlier in this series.
With every consumer of struct gss_krb5_enctype removed, replace
its remaining uses with the equivalent fields from struct
krb5_enctype (key_len). Remove struct gss_krb5_enctype, the
supported_gss_krb5_enctypes[] table, gss_krb5_lookup_enctype(),
and the gk5e pointer from krb5_ctx.
Assisted-by: Claude:claude-opus-4-6
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The crypto/krb5 library accepts data in scatterlist form, but
the GSS-API layer presents RPC payloads as struct xdr_buf.
Bridge that gap with a pair of helper functions:
xdr_buf_to_sg() - populate a caller-supplied scatterlist
array from a byte range
xdr_buf_to_sg_alloc() - populate a caller-supplied inline
scatterlist, chaining to a heap-
allocated overflow for large payloads
The inline array (typically stack-allocated at eight entries)
covers the common case of small RPCs with no heap allocation
on the encrypt/decrypt path. Only buffers spanning many pages
incur a kmalloc for the chained extension.
The segment-walking logic follows the same head, page array,
tail traversal as xdr_process_buf(), but populates a
scatterlist directly rather than invoking a per-segment
callback. sg_next() traversal makes the walker safe for
chained scatterlists. Once subsequent patches reroute all
per-message crypto operations through crypto/krb5,
xdr_process_buf() loses its last callers and is removed.
Assisted-by: Claude:claude-opus-4-6
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Anna Schumaker <anna.schumaker@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable fixes:
- don't inherit NFS filesystem capabilities when crossing from one
filesystem to another
Bugfixes:
- NFS wakeup of __nfs_lookup_revalidate() needs memory barriers
- NFS improve bounds checking in nfs_fh_to_dentry()
- NFS Fix allocation errors when writing to a NFS file backed
loopback device
- NFSv4: More listxattr fixes
- SUNRPC: fix client handling of TLS alerts
- pNFS block/scsi layout fix for an uninitialised pointer
dereference
- pNFS block/scsi layout fixes for the extent encoding, stripe
mapping, and disk offset overflows
- pNFS layoutcommit work around for RPC size limitations
- pNFS/flexfiles avoid looping when handling fatal errors after
layoutget
- localio: fix various race conditions
Features and cleanups:
- Add NFSv4 support for retrieving the btime
- NFS: Allow folio migration for the case of mode == MIGRATE_SYNC
- NFS: Support using a kernel keyring to store TLS certificates
- NFSv4: Speed up delegation lookup using a hash table
- Assorted cleanups to remove unused variables and struct fields
- Assorted new tracepoints to improve debugging"
* tag 'nfs-for-6.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (44 commits)
NFS/localio: nfs_uuid_put() fix the wake up after unlinking the file
NFS/localio: nfs_uuid_put() fix races with nfs_open/close_local_fh()
NFS/localio: nfs_close_local_fh() fix check for file closed
NFSv4: Remove duplicate lookups, capability probes and fsinfo calls
NFS: Fix the setting of capabilities when automounting a new filesystem
sunrpc: fix client side handling of tls alerts
nfs/localio: use read_seqbegin() rather than read_seqbegin_or_lock()
NFS: Fixup allocation flags for nfsiod's __GFP_NORETRY
NFSv4.2: another fix for listxattr
NFS: Fix filehandle bounds checking in nfs_fh_to_dentry()
SUNRPC: Silence warnings about parameters not being described
NFS: Clean up pnfs_put_layout_hdr()/pnfs_destroy_layout_final()
NFS: Fix wakeup of __nfs_lookup_revalidate() in unblock_revalidate()
NFS: use a hash table for delegation lookup
NFS: track active delegations per-server
NFS: move the delegation_watermark module parameter
NFS: cleanup nfs_inode_reclaim_delegation
NFS: cleanup error handling in nfs4_server_common_setup
pNFS/flexfiles: don't attempt pnfs on fatal DS errors
NFS: drop __exit from nfs_exit_keyring
...
Remove a bunch of unused xdr_*decode* functions:
The last use of xdr_decode_netobj() was removed in 2021 by:
commit 7cf96b6d01 ("lockd: Update the NLMv4 SHARE arguments decoder to
use struct xdr_stream")
The last use of xdr_decode_string_inplace() was removed in 2021 by:
commit 3049e974a7 ("lockd: Update the NLMv4 FREE_ALL arguments decoder
to use struct xdr_stream")
The last use of xdr_stream_decode_opaque() was removed in 2024 by:
commit fed8a17c61 ("xdrgen: typedefs should use the built-in string and
opaque functions")
The functions xdr_stream_decode_string() and
xdr_stream_decode_opaque_dup() were both added in 2018 by the
commit 0e779aa703 ("SUNRPC: Add helpers for decoding opaque and string
types")
but never used.
Remove them.
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Link: https://lore.kernel.org/r/20250712233006.403226-1-linux@treblig.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The rqst argument to xdr_init_encode_pages is set to NULL by all callers,
and pages is always set to buf->pages. Remove the two arguments and
hardcode the assignments.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
A subtlety of this API is that if the @nbytes region traverses a
page boundary, the next __xdr_commit_encode will shift the data item
in the XDR encode buffer. This makes the returned pointer point to
something else, leading to unexpected behavior.
There are a few cases where the caller saves the returned pointer
and then later uses it to insert a computed value into an earlier
part of the stream. This can be safe only if either:
- the data item is guaranteed to be in the XDR buffer's head, and
thus is not ever going to be near a page boundary, or
- the data item is no larger than 4 octets, since XDR alignment
rules require all data items to start on 4-octet boundaries
But that safety is only an artifact of the current implementation.
It would be less brittle if these "safe" uses were eventually
replaced.
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Pull NFS client updates from Anna Schumaker:
"New Features:
- Enable the NFS v4.2 READ_PLUS operation by default
Stable Fixes:
- NFSv4/pnfs: minor fix for cleanup path in nfs4_get_device_info
- NFS: Fix a potential data corruption
Bugfixes:
- Fix various READ_PLUS issues including:
- smatch warnings
- xdr size calculations
- scratch buffer handling
- 32bit / highmem xdr page handling
- Fix checkpatch errors in file.c
- Fix redundant readdir request after an EOF
- Fix handling of COPY ERR_OFFLOAD_NO_REQ
- Fix assignment of xprtdata.cred
Cleanups:
- Remove unused xprtrdma function declarations
- Clean up an integer overflow check to avoid a warning
- Clean up #includes in dns_resolve.c
- Clean up nfs4_get_device_info so we don't pass a NULL pointer
to __free_page()
- Clean up sunrpc TCP socket timeout configuration
- Guard against READDIR loops when entry names are too long
- Use EXCHID4_FLAG_USE_PNFS_DS for DS servers"
* tag 'nfs-for-6.6-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (22 commits)
pNFS: Fix assignment of xprtdata.cred
NFSv4.2: fix handling of COPY ERR_OFFLOAD_NO_REQ
NFS: Guard against READDIR loop when entry names exceed MAXNAMELEN
NFSv4.1: use EXCHGID4_FLAG_USE_PNFS_DS for DS server
NFS/pNFS: Set the connect timeout for the pNFS flexfiles driver
SUNRPC: Don't override connect timeouts in rpc_clnt_add_xprt()
SUNRPC: Allow specification of TCP client connect timeout at setup
SUNRPC: Refactor and simplify connect timeout
SUNRPC: Set the TCP_SYNCNT to match the socket timeout
NFS: Fix a potential data corruption
nfs: fix redundant readdir request after get eof
nfs/blocklayout: Use the passed in gfp flags
filemap: Fix errors in file.c
NFSv4/pnfs: minor fix for cleanup path in nfs4_get_device_info
NFS: Move common includes outside ifdef
SUNRPC: clean up integer overflow check
xprtrdma: Remove unused function declaration rpcrdma_bc_post_recv()
NFS: Enable the READ_PLUS operation by default
SUNRPC: kmap() the xdr pages during decode
NFSv4.2: Rework scratch handling for READ_PLUS (again)
...
Add a helper to convert a whole xdr_buf directly into an array of
bio_vecs, then send this array instead of iterating piecemeal over
the xdr_buf containing the outbound RPC message.
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
If the pages are in HIGHMEM then we need to make sure they're mapped
before trying to read data off of them, otherwise we could end up with a
NULL pointer dereference.
The downside to this is that we need an extra cleanup step at the end of
decode to kunmap() the last page. I introduced an xdr_finish_decode()
function to do this. Right now this function only calls the
unmap_current_page() function, but other generic cleanup steps could be
added in the future if we come across anything else.
Reported-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Now that the preparation of an rq_vec has been removed from the
generic read path, nfsd_splice_read() no longer needs to reset
rq_next_page.
nfsd4_encode_read() calls nfsd_splice_read() directly. As far as I
can ascertain, resetting rq_next_page for NFSv4 splice reads is
unnecessary because rq_next_page is already set correctly.
Moreover, resetting it might even be incorrect if previous
operations in the COMPOUND have already consumed at least a page of
the send buffer. I would expect that the result would be encoding
the READ payload over previously-encoded results.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Pull nfsd updates from Chuck Lever:
"Two significant security enhancements are part of this release:
- NFSD's RPC header encoding and decoding, including RPCSEC GSS and
gssproxy header parsing, has been overhauled to make it more
memory-safe.
- Support for Kerberos AES-SHA2-based encryption types has been added
for both the NFS client and server. This provides a clean path for
deprecating and removing insecure encryption types based on DES and
SHA-1. AES-SHA2 is also FIPS-140 compliant, so that NFS with
Kerberos may now be used on systems with fips enabled.
In addition to these, NFSD is now able to handle crossing into an
auto-mounted mount point on an exported NFS mount. A number of fixes
have been made to NFSD's server-side copy implementation.
RPC metrics have been converted to per-CPU variables. This helps
reduce unnecessary cross-CPU and cross-node memory bus traffic, and
significantly reduces noise when KCSAN is enabled"
* tag 'nfsd-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (121 commits)
NFSD: Clean up nfsd_symlink()
NFSD: copy the whole verifier in nfsd_copy_write_verifier
nfsd: don't fsync nfsd_files on last close
SUNRPC: Fix occasional warning when destroying gss_krb5_enctypes
nfsd: fix courtesy client with deny mode handling in nfs4_upgrade_open
NFSD: fix problems with cleanup on errors in nfsd4_copy
nfsd: fix race to check ls_layouts
nfsd: don't hand out delegation on setuid files being opened for write
SUNRPC: Remove ->xpo_secure_port()
SUNRPC: Clean up the svc_xprt_flags() macro
nfsd: remove fs/nfsd/fault_inject.c
NFSD: fix leaked reference count of nfsd4_ssc_umount_item
nfsd: clean up potential nfsd_file refcount leaks in COPY codepath
nfsd: zero out pointers after putting nfsd_files on COPY setup error
SUNRPC: Fix whitespace damage in svcauth_unix.c
nfsd: eliminate __nfs4_get_fd
nfsd: add some kerneldoc comments for stateid preprocessing functions
nfsd: eliminate find_deleg_file_locked
nfsd: don't take nfsd4_copy ref for OP_OFFLOAD_STATUS
SUNRPC: Add encryption self-tests
...
RFC 5531 defines an MSG_ACCEPTED Reply message like this:
struct accepted_reply {
opaque_auth verf;
union switch (accept_stat stat) {
case SUCCESS:
...
In the current server code, struct opaque_auth encoding is open-
coded. Introduce a helper that encodes an opaque_auth data item
within the context of a xdr_stream.
Done as part of hardening the server-side RPC header decoding and
encoding paths.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Done as part of hardening the server-side RPC header decoding path.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Done as part of hardening the server-side RPC header decoding path.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
RFC 5531 defines the body of an RPC Call message like this:
struct call_body {
unsigned int rpcvers;
unsigned int prog;
unsigned int vers;
unsigned int proc;
opaque_auth cred;
opaque_auth verf;
/* procedure-specific parameters start here */
};
In the current server code, decoding a struct opaque_auth type is
open-coded in several places, and is thus difficult to harden
everywhere.
Introduce a helper for decoding an opaque_auth within the context
of a xdr_stream. This helper can be shared with all authentication
flavor implemenations, even on the client-side.
Done as part of hardening the server-side RPC header decoding paths.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Make it more evident how xdr_write_pages() updates the tail buffer
by using the convention of naming the iov pointer variable "tail".
I spent more than a couple of hours chasing through code to
understand this, so someone is likely to find this useful later.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
The dust has settled a bit and it's become obvious what code is
totally common between nfsd_init_dirlist_pages() and
nfsd3_init_dirlist_pages(). Move that common code to SUNRPC.
The new helper brackets the existing xdr_init_decode_pages() API.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
We need to do this step during READ_PLUS decoding so that we know pages
are the right length and any extra data has been preserved in the tail.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
I do this by creating an xdr subsegment for the range we will be
operating over. This lets me shift data to the correct place without
potentially overwriting anything already there.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
To make the code easier to read, remove visual clutter by changing
the declared type of @p.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
The value of @p is not used until the "location of the next item" is
computed. Help human readers by moving its initial assignment to the
paragraph where that value is used and by clarifying the antecedents
in the documenting comment.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Both the kvec::iov_len field and the third parameter of memcpy() and
memmove() are size_t. There's no reason for the implicit conversion
from size_t to int and back. Change the type of @shift to make the
code easier to read and understand.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Transitioning between encode buffers is quite infrequent. It happens
about 1 time in 400 calls to xdr_reserve_space(), measured on NFSD
with a typical build/test workload.
Force the compiler to remove that code from xdr_reserve_space(),
which is a hot path on both the server and the client. This change
reduces the size of xdr_reserve_space() from 10 cache lines to 2
when compiled with -Os.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
I found that NFSD's new NFSv3 READDIRPLUS XDR encoder was screwing up
right at the end of the page array. xdr_get_next_encode_buffer() does
not compute the value of xdr->end correctly:
* The check to see if we're on the final available page in xdr->buf
needs to account for the space consumed by @nbytes.
* The new xdr->end value needs to account for the portion of @nbytes
that is to be encoded into the previous buffer.
Fixes: 2825a7f907 ("nfsd4: allow encoding across page boundaries")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
xdr_stream_subsegment() was introduced in commit c1346a1216
("NFSD: Replace the internals of the READ_BUF() macro").
There are two call sites for xdr_stream_subsegment(). One is
nfsd4_decode_write(), and the other is nfsd4_decode_setxattr().
Currently neither of these call sites calls this API when
xdr_buf::page_base is a non-zero value.
However, I'm about to add a case where page_base will sometimes not
be zero when nfsd4_decode_write() invokes this API. Replace the
logic in xdr_stream_subsegment() that advances to the next data item
in the xdr_stream with something more generic in order to handle
this new use case.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This seems to happen fairly easily during READ_PLUS testing on NFS v4.2.
I found that we could end up accessing xdr->buf->pages[pgnr] with a pgnr
greater than the number of pages in the array. So let's just return
early if we're setting base to a point at the end of the page data and
let xdr_set_tail_base() handle setting up the buffer pointers instead.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Fixes: 8d86e373b0 ("SUNRPC: Clean up helpers xdr_set_iov() and xdr_set_page_base()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Features:
- NFSv3: Add emulation of lookupp() to improve open_by_filehandle()
support
- A series of patches to improve readdir performance, particularly
with large directories
- Basic support for using NFS/RDMA with the pNFS files and flexfiles
drivers
- Micro-optimisations for RDMA
- RDMA tracing improvements
Bugfixes:
- Fix a long standing bug with xs_read_xdr_buf() when receiving
partial pages (Dan Aloni)
- Various fixes for getxattr and listxattr, when used over non-TCP
transports
- Fixes for containerised NFS from Sargun Dhillon
- switch nfsiod to be an UNBOUND workqueue (Neil Brown)
- READDIR should not ask for security label information if there is
no LSM policy (Olga Kornievskaia)
- Avoid using interval-based rebinding with TCP in lockd (Calum
Mackay)
- A series of RPC and NFS layer fixes to support the NFSv4.2
READ_PLUS code
- A couple of fixes for pnfs/flexfiles read failover
Cleanups:
- Various cleanups for the SUNRPC xdr code in conjunction with the
READ_PLUS fixes"
* tag 'nfs-for-5.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (90 commits)
NFS/pNFS: Fix a typo in ff_layout_resend_pnfs_read()
pNFS/flexfiles: Avoid spurious layout returns in ff_layout_choose_ds_for_read
NFSv4/pnfs: Add tracing for the deviceid cache
fs/lockd: convert comma to semicolon
NFSv4.2: fix error return on memory allocation failure
NFSv4.2/pnfs: Don't use READ_PLUS with pNFS yet
NFSv4.2: Deal with potential READ_PLUS data extent buffer overflow
NFSv4.2: Don't error when exiting early on a READ_PLUS buffer overflow
NFSv4.2: Handle hole lengths that exceed the READ_PLUS read buffer
NFSv4.2: decode_read_plus_hole() needs to check the extent offset
NFSv4.2: decode_read_plus_data() must skip padding after data segment
NFSv4.2: Ensure we always reset the result->count in decode_read_plus()
SUNRPC: When expanding the buffer, we may need grow the sparse pages
SUNRPC: Cleanup - constify a number of xdr_buf helpers
SUNRPC: Clean up open coded setting of the xdr_stream 'nwords' field
SUNRPC: _copy_to/from_pages() now check for zero length
SUNRPC: Cleanup xdr_shrink_bufhead()
SUNRPC: Fix xdr_expand_hole()
SUNRPC: Fixes for xdr_align_data()
SUNRPC: _shift_data_left/right_pages should check the shift length
...
If we're shifting the page data to the right, and this happens to be a
sparse page array, then we may need to allocate new pages in order to
receive the data.
Reported-by: "Mkrtchyan, Tigran" <tigran.mkrtchyan@desy.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
There are a number of xdr helpers for struct xdr_buf that do not change
the structure itself. Mark those as taking const pointers for
documentation purposes.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Move the setting of the xdr_stream 'nwords' field into the helpers that
reset the xdr_stream cursor.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
We do want to try to grow the buffer if possible, but if that attempt
fails, we still want to move the data and truncate the XDR message.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The main use case right now for xdr_align_data() is to shift the page
data to the left, and in practice shrink the total XDR data buffer.
This patch ensures that we fix up the accounting for the buffer length
as we shift that data around.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
While we always want to align to the next page and/or the beginning of
the tail buffer when we call xdr_set_next_page(), the functions
xdr_align_data() and xdr_expand_hole() really want to align to the next
object in that next page or tail.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
rpc_prepare_reply_pages() currently expects the 'hdrsize' argument to
contain the length of the data that we expect to want placed in the head
kvec plus a count of 1 word of padding that is placed after the page data.
This is very confusing when trying to read the code, and sometimes leads
to callers adding an arbitrary value of '1' just in order to satisfy the
requirement (whether or not the page data actually needs such padding).
This patch aims to clarify the code by changing the 'hdrsize' argument
to remove that 1 word of padding. This means we need to subtract the
padding from all the existing callers.
Fixes: 02ef04e432 ("NFS: Account for XDR pad of buf->pages")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Fix up xdr_read_pages() so that it can handle object lengths that are
larger than the page length, by simply aligning to the next object in
the buffer tail.
The function will continue to return the length of the truncate object
data that actually fit into the pages.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Allow xdr_set_iov() to set a base so that we can use it to set the
cursor to a specific position in the kvec buffer.
If the new base overflows the kvec/pages buffer in either xdr_set_iov()
or xdr_set_page_base(), then truncate it so that we point to the end of
the buffer.
Finally, change both function to return the number of bytes remaining to
read in their buffers.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
We already know that the head buffer and page are empty, so if there is
any data, it is in the tail.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
