[ Upstream commit 7b6275c80a ]
In the event that rpcrdma_post_recvs() fails to create a work request
(due to memory allocation failure, say) or otherwise exits early, we
should decrement ep->re_receiving before returning. Otherwise we will
hang in rpcrdma_xprt_drain() as re_receiving will never reach zero and
the completion will never be triggered.
On a system with high memory pressure, this can appear as the following
hung task:
INFO: task kworker/u385:17:8393 blocked for more than 122 seconds.
Tainted: G S E 6.19.0 #3
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u385:17 state:D stack:0 pid:8393 tgid:8393 ppid:2 task_flags:0x4248060 flags:0x00080000
Workqueue: xprtiod xprt_autoclose [sunrpc]
Call Trace:
<TASK>
__schedule+0x48b/0x18b0
? ib_post_send_mad+0x247/0xae0 [ib_core]
schedule+0x27/0xf0
schedule_timeout+0x104/0x110
__wait_for_common+0x98/0x180
? __pfx_schedule_timeout+0x10/0x10
wait_for_completion+0x24/0x40
rpcrdma_xprt_disconnect+0x444/0x460 [rpcrdma]
xprt_rdma_close+0x12/0x40 [rpcrdma]
xprt_autoclose+0x5f/0x120 [sunrpc]
process_one_work+0x191/0x3e0
worker_thread+0x2e3/0x420
? __pfx_worker_thread+0x10/0x10
kthread+0x10d/0x230
? __pfx_kthread+0x10/0x10
ret_from_fork+0x273/0x2b0
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
Fixes: 15788d1d10 ("xprtrdma: Do not refresh Receive Queue while it is draining")
Signed-off-by: Eric Badger <ebadger@purestorage.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit dd2fdc3504 upstream.
Commit 5940d1cf9f ("SUNRPC: Rebalance a kref in auth_gss.c") added
a kref_get(&gss_auth->kref) call to balance the gss_put_auth() done
in gss_release_msg(), but forgot to add a corresponding kref_put()
on the error path when kstrdup_const() fails.
If service_name is non-NULL and kstrdup_const() fails, the function
jumps to err_put_pipe_version which calls put_pipe_version() and
kfree(gss_msg), but never releases the gss_auth reference. This leads
to a kref leak where the gss_auth structure is never freed.
Add a forward declaration for gss_free_callback() and call kref_put()
in the err_put_pipe_version error path to properly release the
reference taken earlier.
Fixes: 5940d1cf9f ("SUNRPC: Rebalance a kref in auth_gss.c")
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Hodges <git@danielhodges.dev>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3e6397b056 upstream.
The gssx_dec_ctx(), gssx_dec_status(), and gssx_dec_name()
functions allocate memory via gssx_dec_buffer(), which calls
kmemdup(). When a subsequent decode operation fails, these
functions return immediately without freeing previously
allocated buffers, causing memory leaks.
The leak in gssx_dec_ctx() is particularly relevant because
the caller (gssp_accept_sec_context_upcall) initializes several
buffer length fields to non-zero values, resulting in memory
allocation:
struct gssx_ctx rctxh = {
.exported_context_token.len = GSSX_max_output_handle_sz,
.mech.len = GSS_OID_MAX_LEN,
.src_name.display_name.len = GSSX_max_princ_sz,
.targ_name.display_name.len = GSSX_max_princ_sz
};
If, for example, gssx_dec_name() succeeds for src_name but
fails for targ_name, the memory allocated for
exported_context_token, mech, and src_name.display_name
remains unreferenced and cannot be reclaimed.
Add error handling with goto-based cleanup to free any
previously allocated buffers before returning an error.
Reported-by: Xingjing Deng <micro6947@gmail.com>
Closes: https://lore.kernel.org/linux-nfs/CAK+ZN9qttsFDu6h1FoqGadXjMx1QXqPMoYQ=6O9RY4SxVTvKng@mail.gmail.com/
Fixes: 1d658336b0 ("SUNRPC: Add RPC based upcall mechanism for RPCGSS auth")
Cc: stable@vger.kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit afcae7d7b8 ]
svc_rdma_accept() computes sc_sq_depth as the sum of rq_depth and the
number of rdma_rw contexts (ctxts). This value is used to allocate the
Send CQ and to initialize the sc_sq_avail credit pool.
However, when the device uses memory registration for RDMA operations,
rdma_rw_init_qp() inflates the QP's max_send_wr by a factor of three
per context to account for REG and INV work requests. The Send CQ and
credit pool remain sized for only one work request per context,
causing Send Queue exhaustion under heavy NFS WRITE workloads.
Introduce rdma_rw_max_sge() to compute the actual number of Send Queue
entries required for a given number of rdma_rw contexts. Upper layer
protocols call this helper before creating a Queue Pair so that their
Send CQs and credit accounting match the QP's true capacity.
Update svc_rdma_accept() to use rdma_rw_max_sge() when computing
sc_sq_depth, ensuring the credit pool reflects the work requests
that rdma_rw_init_qp() will reserve.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Fixes: 00bd1439f4 ("RDMA/rw: Support threshold for registration vs scattering to local pages")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Link: https://patch.msgid.link/20260128005400.25147-5-cel@kernel.org
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d1bea0ce35 ]
svc_rdma_copy_inline_range indexed rqstp->rq_pages[rc_curpage] without
verifying rc_curpage stays within the allocated page array. Add guards
before the first use and after advancing to a new page.
Fixes: d7cc739726 ("svcrdma: support multiple Read chunks per RPC")
Cc: stable@vger.kernel.org
Signed-off-by: Joshua Rogers <linux@joshua.hu>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[ replaced rqstp->rq_maxpages with ARRAY_SIZE(rqstp->rq_pages) ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d4b69a6186 upstream.
A zero length gss_token results in pages == 0 and in_token->pages[0]
is NULL. The code unconditionally evaluates
page_address(in_token->pages[0]) for the initial memcpy, which can
dereference NULL even when the copy length is 0. Guard the first
memcpy so it only runs when length > 0.
Fixes: 5866efa8cb ("SUNRPC: Fix svcauth_gss_proxy_init()")
Cc: stable@vger.kernel.org
Signed-off-by: Joshua Rogers <linux@joshua.hu>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a8ee9099f3 upstream.
svc_rdma_copy_inline_range added rc_curpage (page index) to the page
base instead of the byte offset rc_pageoff. Use rc_pageoff so copies
land within the current page.
Found by ZeroPath (https://zeropath.com)
Fixes: 8e12258268 ("svcrdma: Move svc_rdma_read_info::ri_pageno to struct svc_rdma_recv_ctxt")
Cc: stable@vger.kernel.org
Signed-off-by: Joshua Rogers <linux@joshua.hu>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 898374fdd7 ]
When a listener is added, a part of creation of transport also registers
program/port with rpcbind. However, when the listener is removed,
while transport goes away, rpcbind still has the entry for that
port/type.
When deleting the transport, unregister with rpcbind when appropriate.
---v2 created a new xpt_flag XPT_RPCB_UNREG to mark TCP and UDP
transport and at xprt destroy send rpcbind unregister if flag set.
Suggested-by: Chuck Lever <chuck.lever@oracle.com>
Fixes: d093c90892 ("nfsd: fix management of listener transports")
Cc: stable@vger.kernel.org
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit eccbbc7c00 ]
The heuristic for limiting the number of incoming connections to nfsd
currently uses sv_nrthreads - allowing more connections if more threads
were configured.
A future patch will allow number of threads to grow dynamically so that
there will be no need to configure sv_nrthreads. So we need a different
solution for limiting connections.
It isn't clear what problem is solved by limiting connections (as
mentioned in a code comment) but the most likely problem is a connection
storm - many connections that are not doing productive work. These will
be closed after about 6 minutes already but it might help to slow down a
storm.
This patch adds a per-connection flag XPT_PEER_VALID which indicates
that the peer has presented a filehandle for which it has some sort of
access. i.e the peer is known to be trusted in some way. We now only
count connections which have NOT been determined to be valid. There
should be relative few of these at any given time.
If the number of non-validated peer exceed a limit - currently 64 - we
close the oldest non-validated peer to avoid having too many of these
useless connections.
Note that this patch significantly changes the meaning of the various
configuration parameters for "max connections". The next patch will
remove all of these.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Stable-dep-of: 898374fdd7 ("nfsd: unregister with rpcbind when deleting a transport")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6df164e29b upstream.
In xdr_stream_decode_opaque_auth(), zero-length checksum.len causes
checksum.data to be set to NULL. This triggers a NPD when accessing
checksum.data in gss_krb5_verify_mic_v2(). This patch ensures that
the value of checksum.len is not less than XDR_UNIT.
Fixes: 0653028e8f ("SUNRPC: Convert gss_verify_header() to use xdr_stream")
Cc: stable@kernel.org
Signed-off-by: Lei Lu <llfamsec@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9559d2fffd ]
xs_sock_recv_cmsg was failing to call xs_sock_process_cmsg for any cmsg
type other than TLS_RECORD_TYPE_ALERT (TLS_RECORD_TYPE_DATA, and other
values not handled.) Based on my reading of the previous commit
(cc5d5908: sunrpc: fix client side handling of tls alerts), it looks
like only iov_iter_revert should be conditional on TLS_RECORD_TYPE_ALERT
(but that other cmsg types should still call xs_sock_process_cmsg). On
my machine, I was unable to connect (over mtls) to an NFS share hosted
on FreeBSD. With this patch applied, I am able to mount the share again.
Fixes: cc5d59081f ("sunrpc: fix client side handling of tls alerts")
Signed-off-by: Justin Worrell <jworrell@gmail.com>
Reviewed-and-tested-by: Scott Mayhew <smayhew@redhat.com>
Link: https://lore.kernel.org/r/20250904211038.12874-3-jworrell@gmail.com
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit bee47cb026 upstream.
Scott Mayhew discovered a security exploit in NFS over TLS in
tls_alert_recv() due to its assumption it can read data from
the msg iterator's kvec..
kTLS implementation splits TLS non-data record payload between
the control message buffer (which includes the type such as TLS
aler or TLS cipher change) and the rest of the payload (say TLS
alert's level/description) which goes into the msg payload buffer.
This patch proposes to rework how control messages are setup and
used by sock_recvmsg().
If no control message structure is setup, kTLS layer will read and
process TLS data record types. As soon as it encounters a TLS control
message, it would return an error. At that point, NFS can setup a
kvec backed msg buffer and read in the control message such as a
TLS alert. Msg iterator can advance the kvec pointer as a part of
the copy process thus we need to revert the iterator before calling
into the tls_alert_recv.
Reported-by: Scott Mayhew <smayhew@redhat.com>
Fixes: 5e052dda12 ("SUNRPC: Recognize control messages in server-side TCP socket code")
Suggested-by: Trond Myklebust <trondmy@hammerspace.com>
Cc: stable@vger.kernel.org
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit cc5d59081f ]
A security exploit was discovered in NFS over TLS in tls_alert_recv
due to its assumption that there is valid data in the msghdr's
iterator's kvec.
Instead, this patch proposes the rework how control messages are
setup and used by sock_recvmsg().
If no control message structure is setup, kTLS layer will read and
process TLS data record types. As soon as it encounters a TLS control
message, it would return an error. At that point, NFS can setup a kvec
backed control buffer and read in the control message such as a TLS
alert. Scott found that a msg iterator can advance the kvec pointer
as a part of the copy process thus we need to revert the iterator
before calling into the tls_alert_recv.
Fixes: dea034b963 ("SUNRPC: Capture CMSG metadata on client-side receive")
Suggested-by: Trond Myklebust <trondmy@hammerspace.com>
Suggested-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Link: https://lore.kernel.org/r/20250731180058.4669-3-okorniev@redhat.com
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c1feab95e0 ]
Quite a few places want to build a struct qstr by given string;
it would be convenient to have a primitive doing that, rather
than open-coding it via QSTR_INIT().
The closest approximation was in bcachefs, but that expands to
initializer list - {.len = strlen(string), .name = string}.
It would be more useful to have it as compound literal -
(struct qstr){.len = strlen(string), .name = string}.
Unlike initializer list it's a valid expression. What's more,
it's a valid lvalue - it's an equivalent of anonymous local
variable with such initializer, so the things like
path->dentry = d_alloc_pseudo(mnt->mnt_sb, &QSTR(name));
are valid. It can also be used as initializer, with identical
effect -
struct qstr x = (struct qstr){.name = s, .len = strlen(s)};
is equivalent to
struct qstr anon_variable = {.name = s, .len = strlen(s)};
struct qstr x = anon_variable;
// anon_variable is never used after that point
and any even remotely sane compiler will manage to collapse that
into
struct qstr x = {.name = s, .len = strlen(s)};
What compound literals can't be used for is initialization of
global variables, but those are covered by QSTR_INIT().
This commit lifts definition(s) of QSTR() into linux/dcache.h,
converts it to compound literal (all bcachefs users are fine
with that) and converts assorted open-coded instances to using
that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Stable-dep-of: cbe4134ea4 ("fs: export anon_inode_make_secure_inode() and fix secretmem LSM bypass")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fadc0f3bb2 ]
RFC2203 requires that retransmitted messages use a new gss sequence
number, but the same XID. This means that if the server is just slow
(e.x. overloaded), the client might receive a response using an older
seqno than the one it has recorded.
Currently, Linux's client immediately retransmits in this case. However,
this leads to a lot of wasted retransmits until the server eventually
responds faster than the client can resend.
Client -> SEQ 1 -> Server
Client -> SEQ 2 -> Server
Client <- SEQ 1 <- Server (misses, expecting seqno = 2)
Client -> SEQ 3 -> Server (immediate retransmission on miss)
Client <- SEQ 2 <- Server (misses, expecting seqno = 3)
Client -> SEQ 4 -> Server (immediate retransmission on miss)
... and so on ...
This commit makes it so that we ignore messages with bad checksums
due to seqnum mismatch, and rely on the usual timeout behavior for
retransmission instead of doing so immediately.
Signed-off-by: Nikhil Jha <njha@janestreet.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 94d10a4dba upstream.
tianshuo han reported a remotely-triggerable crash if the client sends a
kernel RPC server a specially crafted packet. If decoding the RPC reply
fails in such a way that SVC_GARBAGE is returned without setting the
rq_accept_statp pointer, then that pointer can be dereferenced and a
value stored there.
If it's the first time the thread has processed an RPC, then that
pointer will be set to NULL and the kernel will crash. In other cases,
it could create a memory scribble.
The server sunrpc code treats a SVC_GARBAGE return from svc_authenticate
or pg_authenticate as if it should send a GARBAGE_ARGS reply. RFC 5531
says that if authentication fails that the RPC should be rejected
instead with a status of AUTH_ERR.
Handle a SVC_GARBAGE return as an AUTH_ERROR, with a reason of
AUTH_BADCRED instead of returning GARBAGE_ARGS in that case. This
sidesteps the whole problem of touching the rpc_accept_statp pointer in
this situation and avoids the crash.
Cc: stable@kernel.org
Fixes: 29cd2927fb ("SUNRPC: Fix encoding of accepted but unsuccessful RPC replies")
Reported-by: tianshuo han <hantianshuo233@gmail.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8ac6fcae5d upstream.
To handle device removal, svc_rdma_accept() requests removal
notification for the underlying device when accepting a connection.
However svc_rdma_free() is not invoked if svc_rdma_accept() fails.
There needs to be a matching "unregister" in that case; otherwise
the device cannot be removed.
Fixes: c4de97f7c4 ("svcrdma: Handle device removal outside of the CM event handler")
Cc: stable@vger.kernel.org
Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0bd2f6b899 upstream.
Engineers at Hammerspace noticed that sometimes mounting with
"xprtsec=tls" hangs for a minute or so, and then times out, even
when the NFS server is reachable and responsive.
kTLS shuts off data_ready callbacks if strp->msg_ready is set to
mitigate data_ready callbacks when a full TLS record is not yet
ready to be read from the socket.
Normally msg_ready is clear when the first TLS record arrives on
a socket. However, I observed that sometimes tls_setsockopt() sets
strp->msg_ready, and that prevents forward progress because
tls_data_ready() becomes a no-op.
Moreover, Jakub says: "If there's a full record queued at the time
when [tlshd] passes the socket back to the kernel, it's up to the
reader to read the already queued data out." So SunRPC cannot
expect a data_ready call when ingress data is already waiting.
Add an explicit poll after SunRPC's upper transport is set up to
pick up any data that arrived after the TLS handshake but before
transport set-up is complete.
Reported-by: Steve Sears <sjs@hammerspace.com>
Suggested-by: Jakub Kacinski <kuba@kernel.org>
Fixes: 75eb6af7ac ("SUNRPC: Add a TCP-with-TLS RPC transport class")
Tested-by: Mike Snitzer <snitzer@kernel.org>
Reviewed-by: Mike Snitzer <snitzer@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5924331589 ]
There is an upper bound on the number of rdma_rw contexts that can
be created per QP.
This invisible upper bound is because rdma_create_qp() adds one or
more additional SQEs for each ctxt that the ULP requests via
qp_attr.cap.max_rdma_ctxs. The QP's actual Send Queue length is on
the order of the sum of qp_attr.cap.max_send_wr and a factor times
qp_attr.cap.max_rdma_ctxs. The factor can be up to three, depending
on whether MR operations are required before RDMA Reads.
This limit is not visible to RDMA consumers via dev->attrs. When the
limit is surpassed, QP creation fails with -ENOMEM. For example:
svcrdma's estimate of the number of rdma_rw contexts it needs is
three times the number of pages in RPCSVC_MAXPAGES. When MAXPAGES
is about 260, the internally-computed SQ length should be:
64 credits + 10 backlog + 3 * (3 * 260) = 2414
Which is well below the advertised qp_max_wr of 32768.
If RPCSVC_MAXPAGES is increased to 4MB, that's 1040 pages:
64 credits + 10 backlog + 3 * (3 * 1040) = 9434
However, QP creation fails. Dynamic printk for mlx5 shows:
calc_sq_size:618:(pid 1514): send queue size (9326 * 256 / 64 -> 65536) exceeds limits(32768)
Although 9326 is still far below qp_max_wr, QP creation still
fails.
Because the total SQ length calculation is opaque to RDMA consumers,
there doesn't seem to be much that can be done about this except for
consumers to try to keep the requested rdma_rw ctxt count low.
Fixes: 2da0f610e7 ("svcrdma: Increase the per-transport rw_ctx count")
Reviewed-by: NeilBrown <neil@brown.name>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 214c13e380 ]
If we already had a valid port number for the RPC service, then we
should not allow the rpcbind client to set it to the invalid value '0'.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 750037aa0a upstream.
On an rdma-capable machine, a start/stop/start and then on a stop of
a knfsd server would lead kref underflow warning because svc_rdma_free
would indiscriminately unregister the rdma device but a listening
transport never calls the rdma_rn_register() thus leading to kref
going down to 0 on the 1st stop of the server and on the 2nd stop
it leads to a problem.
Suggested-by: Chuck Lever <chuck.lever@oracle.com>
Fixes: c4de97f7c4 ("svcrdma: Handle device removal outside of the CM event handler")
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1f7a4f98c1 ]
There is a warning about unused variables when building with W=1 and no procfs:
net/sunrpc/cache.c:1660:30: error: 'cache_flush_proc_ops' defined but not used [-Werror=unused-const-variable=]
1660 | static const struct proc_ops cache_flush_proc_ops = {
| ^~~~~~~~~~~~~~~~~~~~
net/sunrpc/cache.c:1622:30: error: 'content_proc_ops' defined but not used [-Werror=unused-const-variable=]
1622 | static const struct proc_ops content_proc_ops = {
| ^~~~~~~~~~~~~~~~
net/sunrpc/cache.c:1598:30: error: 'cache_channel_proc_ops' defined but not used [-Werror=unused-const-variable=]
1598 | static const struct proc_ops cache_channel_proc_ops = {
| ^~~~~~~~~~~~~~~~~~~~~~
These are used inside of an #ifdef, so replacing that with an
IS_ENABLED() check lets the compiler see how they are used while
still dropping them during dead code elimination.
Fixes: dbf847ecb6 ("knfsd: allow cache_register to return error on failure")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7a2f6f7687 ]
If the TLS handshake attempt returns -ETIMEDOUT, we currently translate
that error into -EACCES. This becomes problematic for cases where the RPC
layer is attempting to re-connect in paths that don't resonably handle
-EACCES, for example: writeback. The RPC layer can handle -ETIMEDOUT quite
well, however - so if the handshake returns this error let's just pass it
along.
Fixes: 75eb6af7ac ("SUNRPC: Add a TCP-with-TLS RPC transport class")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5bbd6e863b ]
If rpc_signal_task() is called while a task is in an rpc_call_done()
callback function, and the latter calls rpc_restart_call(), the task can
end up looping due to the RPC_TASK_SIGNALLED flag being set without the
tk_rpc_status being set.
Removing the redundant mechanism for signalling the task fixes the
looping behaviour.
Reported-by: Li Lingfeng <lilingfeng3@huawei.com>
Fixes: 39494194f9 ("SUNRPC: Fix races with rpc_killall_tasks()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 966a675da8 upstream.
I noticed that a handful of NFSv3 fstests were taking an
unexpectedly long time to run. Troubleshooting showed that the
server's TCP window closed and never re-opened, which caused the
client to trigger an RPC retransmit timeout after 180 seconds.
The client's recovery action was to establish a fresh connection
and retransmit the timed-out requests. This worked, but it adds a
long delay.
I tracked the problem to the commit that attempted to reduce the
rate at which the network layer delivers TCP socket data_ready
callbacks. Under most circumstances this change worked as expected,
but for NFSv3, which has no session or other type of throttling, it
can overwhelm the receiver on occasion.
I'm sure I could tweak the lowat settings, but the small benefit
doesn't seem worth the bother. Just revert it.
Fixes: 2b877fc53e ("SUNRPC: Reduce thread wake-up rate when receiving large RPC messages")
Cc: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3f23f96528 ]
BUG: KASAN: slab-use-after-free in tcp_write_timer_handler+0x156/0x3e0
Read of size 1 at addr ffff888111f322cd by task swapper/0/0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.0-rc4-dirty #7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1
Call Trace:
<IRQ>
dump_stack_lvl+0x68/0xa0
print_address_description.constprop.0+0x2c/0x3d0
print_report+0xb4/0x270
kasan_report+0xbd/0xf0
tcp_write_timer_handler+0x156/0x3e0
tcp_write_timer+0x66/0x170
call_timer_fn+0xfb/0x1d0
__run_timers+0x3f8/0x480
run_timer_softirq+0x9b/0x100
handle_softirqs+0x153/0x390
__irq_exit_rcu+0x103/0x120
irq_exit_rcu+0xe/0x20
sysvec_apic_timer_interrupt+0x76/0x90
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:default_idle+0xf/0x20
Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90
90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 f8 25 00 fb f4 <fa> c3 cc cc cc
cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
RSP: 0018:ffffffffa2007e28 EFLAGS: 00000242
RAX: 00000000000f3b31 RBX: 1ffffffff4400fc7 RCX: ffffffffa09c3196
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9f00590f
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed102360835d
R10: ffff88811b041aeb R11: 0000000000000001 R12: 0000000000000000
R13: ffffffffa202d7c0 R14: 0000000000000000 R15: 00000000000147d0
default_idle_call+0x6b/0xa0
cpuidle_idle_call+0x1af/0x1f0
do_idle+0xbc/0x130
cpu_startup_entry+0x33/0x40
rest_init+0x11f/0x210
start_kernel+0x39a/0x420
x86_64_start_reservations+0x18/0x30
x86_64_start_kernel+0x97/0xa0
common_startup_64+0x13e/0x141
</TASK>
Allocated by task 595:
kasan_save_stack+0x24/0x50
kasan_save_track+0x14/0x30
__kasan_slab_alloc+0x87/0x90
kmem_cache_alloc_noprof+0x12b/0x3f0
copy_net_ns+0x94/0x380
create_new_namespaces+0x24c/0x500
unshare_nsproxy_namespaces+0x75/0xf0
ksys_unshare+0x24e/0x4f0
__x64_sys_unshare+0x1f/0x30
do_syscall_64+0x70/0x180
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Freed by task 100:
kasan_save_stack+0x24/0x50
kasan_save_track+0x14/0x30
kasan_save_free_info+0x3b/0x60
__kasan_slab_free+0x54/0x70
kmem_cache_free+0x156/0x5d0
cleanup_net+0x5d3/0x670
process_one_work+0x776/0xa90
worker_thread+0x2e2/0x560
kthread+0x1a8/0x1f0
ret_from_fork+0x34/0x60
ret_from_fork_asm+0x1a/0x30
Reproduction script:
mkdir -p /mnt/nfsshare
mkdir -p /mnt/nfs/netns_1
mkfs.ext4 /dev/sdb
mount /dev/sdb /mnt/nfsshare
systemctl restart nfs-server
chmod 777 /mnt/nfsshare
exportfs -i -o rw,no_root_squash *:/mnt/nfsshare
ip netns add netns_1
ip link add name veth_1_peer type veth peer veth_1
ifconfig veth_1_peer 11.11.0.254 up
ip link set veth_1 netns netns_1
ip netns exec netns_1 ifconfig veth_1 11.11.0.1
ip netns exec netns_1 /root/iptables -A OUTPUT -d 11.11.0.254 -p tcp \
--tcp-flags FIN FIN -j DROP
(note: In my environment, a DESTROY_CLIENTID operation is always sent
immediately, breaking the nfs tcp connection.)
ip netns exec netns_1 timeout -s 9 300 mount -t nfs -o proto=tcp,vers=4.1 \
11.11.0.254:/mnt/nfsshare /mnt/nfs/netns_1
ip netns del netns_1
The reason here is that the tcp socket in netns_1 (nfs side) has been
shutdown and closed (done in xs_destroy), but the FIN message (with ack)
is discarded, and the nfsd side keeps sending retransmission messages.
As a result, when the tcp sock in netns_1 processes the received message,
it sends the message (FIN message) in the sending queue, and the tcp timer
is re-established. When the network namespace is deleted, the net structure
accessed by tcp's timer handler function causes problems.
To fix this problem, let's hold netns refcnt for the tcp kernel socket as
done in other modules. This is an ugly hack which can easily be backported
to earlier kernels. A proper fix which cleans up the interfaces will
follow, but may not be so easy to backport.
Fixes: 26abe14379 ("net: Modify sk_alloc to not reference count the netns of kernel sockets.")
Signed-off-by: Liu Jian <liujian56@huawei.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d7bdd849ef ]
We've noticed a situation where an unstable TCP connection can cause the
TLS handshake to timeout waiting for userspace to complete it. When this
happens, we don't want to return from xs_tls_handshake_sync() with zero, as
this will cause the upper xprt to be set CONNECTED, and subsequent attempts
to transmit will be returned with -EPIPE. The sunrpc machine does not
recover from this situation and will spin attempting to transmit.
The return value of tls_handshake_cancel() can be used to detect a race
with completion:
* tls_handshake_cancel - cancel a pending handshake
* Return values:
* %true - Uncompleted handshake request was canceled
* %false - Handshake request already completed or not found
If true, we do not want the upper xprt to be connected, so return
-ETIMEDOUT. If false, its possible the handshake request was lost and
that may be the reason for our timeout. Again we do not want the upper
xprt to be connected, so return -ETIMEDOUT.
Ensure that we alway return an error from xs_tls_handshake_sync() if we
call tls_handshake_cancel().
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Fixes: 75eb6af7ac ("SUNRPC: Add a TCP-with-TLS RPC transport class")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4db9ad82a6 ]
Since transport->sock has been set to NULL during reset transport,
XPRT_SOCK_UPD_TIMEOUT also needs to be cleared. Otherwise, the
xs_tcp_set_socket_timeouts() may be triggered in xs_tcp_send_request()
to dereference the transport->sock that has been set to NULL.
Fixes: 7196dbb02e ("SUNRPC: Allow changing of the TCP timeout parameters on the fly")
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 2862eee078 upstream.
The function `c_show` was called with protection from RCU. This only
ensures that `cp` will not be freed. Therefore, the reference count for
`cp` can drop to zero, which will trigger a refcount use-after-free
warning when `cache_get` is called. To resolve this issue, use
`cache_get_rcu` to ensure that `cp` remains active.
------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 7 PID: 822 at lib/refcount.c:25
refcount_warn_saturate+0xb1/0x120
CPU: 7 UID: 0 PID: 822 Comm: cat Not tainted 6.12.0-rc3+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.1-2.fc37 04/01/2014
RIP: 0010:refcount_warn_saturate+0xb1/0x120
Call Trace:
<TASK>
c_show+0x2fc/0x380 [sunrpc]
seq_read_iter+0x589/0x770
seq_read+0x1e5/0x270
proc_reg_read+0xe1/0x140
vfs_read+0x125/0x530
ksys_read+0xc1/0x160
do_syscall_64+0x5f/0x170
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: Yang Erkun <yangerkun@huawei.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ce89e742a4 ]
There's issue as follows:
RPC: Registered rdma transport module.
RPC: Registered rdma backchannel transport module.
RPC: Unregistered rdma transport module.
RPC: Unregistered rdma backchannel transport module.
BUG: unable to handle page fault for address: fffffbfff80c609a
PGD 123fee067 P4D 123fee067 PUD 123fea067 PMD 10c624067 PTE 0
Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI
RIP: 0010:percpu_counter_destroy_many+0xf7/0x2a0
Call Trace:
<TASK>
__die+0x1f/0x70
page_fault_oops+0x2cd/0x860
spurious_kernel_fault+0x36/0x450
do_kern_addr_fault+0xca/0x100
exc_page_fault+0x128/0x150
asm_exc_page_fault+0x26/0x30
percpu_counter_destroy_many+0xf7/0x2a0
mmdrop+0x209/0x350
finish_task_switch.isra.0+0x481/0x840
schedule_tail+0xe/0xd0
ret_from_fork+0x23/0x80
ret_from_fork_asm+0x1a/0x30
</TASK>
If register_sysctl() return NULL, then svc_rdma_proc_cleanup() will not
destroy the percpu counters which init in svc_rdma_proc_init().
If CONFIG_HOTPLUG_CPU is enabled, residual nodes may be in the
'percpu_counters' list. The above issue may occur once the module is
removed. If the CONFIG_HOTPLUG_CPU configuration is not enabled, memory
leakage occurs.
To solve above issue just destroy all percpu counters when
register_sysctl() return NULL.
Fixes: 1e7e557316 ("svcrdma: Restore read and write stats")
Fixes: 22df5a2246 ("svcrdma: Convert rdma_stat_sq_starve to a per-CPU counter")
Fixes: df971cd853 ("svcrdma: Convert rdma_stat_recv to a per-CPU counter")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
xs_tcp_finish_connecting() can return -ENOTCONN but the switch statement
in xs_tcp_setup_socket() treats that as an unhandled error.
If we treat it as a known error it would propagate back to
call_connect_status() which does handle that error code. This appears
to be the intention of the commit (given below) which added -ENOTCONN as
a return status for xs_tcp_finish_connecting().
So add -ENOTCONN to the switch statement as an error to pass through to
the caller.
Link: https://bugzilla.suse.com/show_bug.cgi?id=1231050
Link: https://access.redhat.com/discussions/3434091
Fixes: 01d37c428a ("SUNRPC: xprt_connect() don't abort the task if the transport isn't bound")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Pull nfsd fixes from Chuck Lever:
- Fix two async COPY bugs found during NFS bake-a-thon
- Fix an svcrdma memory leak
* tag 'nfsd-6.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
rpcrdma: Always release the rpcrdma_device's xa_array
NFSD: Never decrement pending_async_copies on error
NFSD: Initialize struct nfsd4_copy earlier
Dai pointed out that the xa_init_flags() in rpcrdma_add_one() needs
to have a matching xa_destroy() in rpcrdma_remove_one() to release
underlying memory that the xarray might have accrued during
operation.
Reported-by: Dai Ngo <dai.ngo@oracle.com>
Fixes: 7e86845a03 ("rpcrdma: Implement generic device removal")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Pull NFS client fixes from Anna Schumaker:
"Localio Bugfixes:
- remove duplicated include in localio.c
- fix race in NFS calls to nfsd_file_put_local() and nfsd_serv_put()
- fix Kconfig for NFS_COMMON_LOCALIO_SUPPORT
- fix nfsd_file tracepoints to handle NULL rqstp pointers
Other Bugfixes:
- fix program selection loop in svc_process_common
- fix integer overflow in decode_rc_list()
- prevent NULL-pointer dereference in nfs42_complete_copies()
- fix CB_RECALL performance issues when using a large number of
delegations"
* tag 'nfs-for-6.12-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
NFS: remove revoked delegation from server's delegation list
nfsd/localio: fix nfsd_file tracepoints to handle NULL rqstp
nfs_common: fix Kconfig for NFS_COMMON_LOCALIO_SUPPORT
nfs_common: fix race in NFS calls to nfsd_file_put_local() and nfsd_serv_put()
NFSv4: Prevent NULL-pointer dereference in nfs42_complete_copies()
SUNRPC: Fix integer overflow in decode_rc_list()
sunrpc: fix prog selection loop in svc_process_common
nfs: Remove duplicated include in localio.c
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.
auto-generated by the following:
for i in `git grep -l -w asm/unaligned.h`; do
sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
If the rq_prog is not in the list of programs, then we use the last
program in the list and we don't get the expected rpc_prog_unavail error
as the subsequent tests on 'progp' being NULL are ineffective.
We should only assign progp when we find the right program, and we
should initialize it to NULL
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Fixes: 86ab08beb3 ("SUNRPC: replace program list with program array")
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
no_llseek had been defined to NULL two years ago, in commit 868941b144
("fs: remove no_llseek")
To quote that commit,
At -rc1 we'll need do a mechanical removal of no_llseek -
git grep -l -w no_llseek | grep -v porting.rst | while read i; do
sed -i '/\<no_llseek\>/d' $i
done
would do it.
Unfortunately, that hadn't been done. Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
.llseek = no_llseek,
so it's obviously safe.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A service created with svc_create_pooled() can be given a linked list of
programs and all of these will be served.
Using a linked list makes it cumbersome when there are several programs
that can be optionally selected with CONFIG settings.
After this patch is applied, API consumers must use only
svc_create_pooled() when creating an RPC service that listens for more
than one RPC program.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Add new funtion svcauth_map_clnt_to_svc_cred_local which maps a
generic cred to a svc_cred suitable for use in nfsd.
This is needed by the localio code to map nfs client creds to nfs
server credentials.
Following from net/sunrpc/auth_unix.c:unx_marshal() it is clear that
->fsuid and ->fsgid must be used (rather than ->uid and ->gid). In
addition, these uid and gid must be translated with from_kuid_munged()
so local client uses correct uid and gid when acting as local server.
Jeff Layton noted:
This is where the magic happens. Since we're working in
kuid_t/kgid_t, we don't need to worry about further idmapping.
Suggested-by: NeilBrown <neilb@suse.de> # to approximate unx_marshal()
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Co-developed-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Remove BUG_ON if p_arglen=0 to allow RPC with void arg.
Remove BUG_ON if p_replen=0 to allow RPC with void return.
The former was needed for the first revision of the LOCALIO protocol
which had an RPC that took a void arg:
/* raw RFC 9562 UUID */
typedef u8 uuid_t<UUID_SIZE>;
program NFS_LOCALIO_PROGRAM {
version LOCALIO_V1 {
void
NULL(void) = 0;
uuid_t
GETUUID(void) = 1;
} = 1;
} = 400122;
The latter is needed for the final revision of the LOCALIO protocol
which has a UUID_IS_LOCAL RPC which returns a void:
/* raw RFC 9562 UUID */
typedef u8 uuid_t<UUID_SIZE>;
program NFS_LOCALIO_PROGRAM {
version LOCALIO_V1 {
void
NULL(void) = 0;
void
UUID_IS_LOCAL(uuid_t) = 1;
} = 1;
} = 400122;
There is really no value in triggering a BUG_ON in response to either
of these previously unsupported conditions.
NeilBrown would like the entire 'if (proc->p_proc != 0)' branch
removed (not just the one BUG_ON that must be removed for LOCALIO's
immediate needs of returning void).
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
list_head can be initialized automatically with LIST_HEAD()
instead of calling INIT_LIST_HEAD(). Here we can simplify
the code.
Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
destroy_wait doesn't store all RPC clients. There was a list named
"all_clients" above it, which got moved to struct sunrpc_net in 2012,
but the comment was never removed.
Fixes: 70abc49b4f ("SUNRPC: make SUNPRC clients list per network namespace context")
Signed-off-by: Siddh Raman Pant <siddh.raman.pant@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Increase size of the servername array to avoid truncated output warning.
net/sunrpc/clnt.c:582:75: error：‘%s’ directive output may be truncated
writing up to 107 bytes into a region of size 48
[-Werror=format-truncation=]
582 | snprintf(servername, sizeof(servername), "%s",
| ^~
net/sunrpc/clnt.c:582:33: note:‘snprintf’ output
between 1 and 108 bytes into a destination of size 48
582 | snprintf(servername, sizeof(servername), "%s",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
583 | sun->sun_path);
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Suggested-by: NeilBrown <neilb@suse.de>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
Using ERR_CAST() is more reasonable and safer, When it is necessary
to convert the type of an error pointer and return it.
Signed-off-by: Yan Zhen <yanzhen@vivo.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
