kernel/linux.git/include/linux/sunrpc/svc.h, branch v5.15.89

SUNRPC: Fix svcxdr_init_encode's buflen calculation

2022-10-26T10:34:38+00:00

[ Upstream commit 1242a87da0d8cd2a428e96ca68e7ea899b0f4624 ] Commit 2825a7f90753 ("nfsd4: allow encoding across page boundaries") added an explicit computation of the remaining length in the rq_res XDR buffer. The computation appears to suffer from an "off-by-one" bug. Because buflen is too large by one page, XDR encoding can run off the end of the send buffer by eventually trying to use the struct page address in rq_page_end, which always contains NULL. Fixes: bddfdbcddbe2 ("NFSD: Extract the svcxdr_init_encode() helper") Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

SUNRPC: Fix svcxdr_init_decode's end-of-buffer calculation

2022-10-26T10:34:38+00:00

[ Upstream commit 90bfc37b5ab91c1a6165e3e5cfc49bf04571b762 ] Ensure that stream-based argument decoding can't go past the actual end of the receive buffer. xdr_init_decode's calculation of the value of xdr->end over-estimates the end of the buffer because the Linux kernel RPC server code does not remove the size of the RPC header from rqstp->rq_arg before calling the upper layer's dispatcher. The server-side still uses the svc_getnl() macros to decode the RPC call header. These macros reduce the length of the head iov but do not update the total length of the message in the buffer (buf->len). A proper fix for this would be to replace the use of svc_getnl() and friends in the RPC header decoder, but that would be a large and invasive change that would be difficult to backport. Fixes: 5191955d6fc6 ("SUNRPC: Prepare for xdr_stream-style decoding on the server-side") Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin

SUNRPC: Fix NFSD's request deferral on RDMA transports

2022-04-20T07:34:18+00:00

commit 773f91b2cf3f52df0d7508fdbf60f37567cdaee4 upstream. Trond Myklebust reports an NFSD crash in svc_rdma_sendto(). Further investigation shows that the crash occurred while NFSD was handling a deferred request. This patch addresses two inter-related issues that prevent request deferral from working correctly for RPC/RDMA requests: 1. Prevent the crash by ensuring that the original svc_rqst::rq_xprt_ctxt value is available when the request is revisited. Otherwise svc_rdma_sendto() does not have a Receive context available with which to construct its reply. 2. Possibly since before commit 71641d99ce03 ("svcrdma: Properly compute .len and .buflen for received RPC Calls"), svc_rdma_recvfrom() did not include the transport header in the returned xdr_buf. There should have been no need for svc_defer() and friends to save and restore that header, as of that commit. This issue is addressed in a backport-friendly way by simply having svc_rdma_recvfrom() set rq_xprt_hlen to zero unconditionally, just as svc_tcp_recvfrom() does. This enables svc_deferred_recv() to correctly reconstruct an RPC message received via RPC/RDMA. Reported-by: Trond Myklebust Link: https://lore.kernel.org/linux-nfs/82662b7190f26fb304eb0ab1bb04279072439d4e.camel@hammerspace.com/ Signed-off-by: Chuck Lever Cc: Signed-off-by: Greg Kroah-Hartman

NFSD: Have legacy NFSD WRITE decoders use xdr_stream_subsegment()

2022-03-08T18:12:33+00:00

[ Upstream commit dae9a6cab8009e526570e7477ce858dcdfeb256e ] Refactor. Now that the NFSv2 and NFSv3 XDR decoders have been converted to use xdr_streams, the WRITE decoder functions can use xdr_stream_subsegment() to extract the WRITE payload into its own xdr_buf, just as the NFSv4 WRITE XDR decoder currently does. That makes it possible to pass the first kvec, pages array + length, page_base, and total payload length via a single function parameter. The payload's page_base is not yet assigned or used, but will be in subsequent patches. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields Signed-off-by: Sasha Levin

Merge tag 'nfs-for-5.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

2021-09-04T17:25:26+00:00

Pull NFS client updates from Anna Schumaker: "New Features: - Better client responsiveness when server isn't replying - Use refcount_t in sunrpc rpc_client refcount tracking - Add srcaddr and dst_port to the sunrpc sysfs info files - Add basic support for connection sharing between servers with multiple NICs` Bugfixes and Cleanups: - Sunrpc tracepoint cleanups - Disconnect after ib_post_send() errors to avoid deadlocks - Fix for tearing down rpcrdma_reps - Fix a potential pNFS layoutget livelock loop - pNFS layout barrier fixes - Fix a potential memory corruption in rpc_wake_up_queued_task_set_status() - Fix reconnection locking - Fix return value of get_srcport() - Remove rpcrdma_post_sends() - Remove pNFS dead code - Remove copy size restriction for inter-server copies - Overhaul the NFS callback service - Clean up sunrpc TCP socket shutdowns - Always provide aligned buffers to RPC read layers" * tag 'nfs-for-5.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (39 commits) NFS: Always provide aligned buffers to the RPC read layers NFSv4.1 add network transport when session trunking is detected SUNRPC enforce creation of no more than max_connect xprts NFSv4 introduce max_connect mount options SUNRPC add xps_nunique_destaddr_xprts to xprt_switch_info in sysfs SUNRPC keep track of number of transports to unique addresses NFSv3: Delete duplicate judgement in nfs3_async_handle_jukebox SUNRPC: Tweak TCP socket shutdown in the RPC client SUNRPC: Simplify socket shutdown when not reusing TCP ports NFSv4.2: remove restriction of copy size for inter-server copy. NFS: Clean up the synopsis of callback process_op() NFS: Extract the xdr_init_encode/decode() calls from decode_compound NFS: Remove unused callback void decoder NFS: Add a private local dispatcher for NFSv4 callback operations SUNRPC: Eliminate the RQ_AUTHERR flag SUNRPC: Set rq_auth_stat in the pg_authenticate() callout SUNRPC: Add svc_rqst::rq_auth_stat SUNRPC: Add dst_port to the sysfs xprt info file SUNRPC: Add srcaddr as a file in sysfs sunrpc: Fix return value of get_srcport() ...

SUNRPC: Fix a NULL pointer deref in trace_svc_stats_latency()

2021-08-17T15:47:53+00:00

Some paths through svc_process() leave rqst->rq_procinfo set to NULL, which triggers a crash if tracing happens to be enabled. Fixes: 89ff87494c6e ("SUNRPC: Display RPC procedure names instead of proc numbers") Signed-off-by: Chuck Lever

SUNRPC: Add svc_rqst_replace_page() API

2021-08-17T15:47:52+00:00

Replacing a page in rq_pages[] requires a get_page(), which is a bus-locked operation, and a put_page(), which can be even more costly. To reduce the cost of replacing a page in rq_pages[], batch the put_page() operations by collecting "freed" pages in a pagevec, and then release those pages when the pagevec is full. This pagevec is also emptied when each RPC completes. Signed-off-by: Chuck Lever

SUNRPC: Eliminate the RQ_AUTHERR flag

2021-08-10T18:18:35+00:00

Now that there is an alternate method for returning an auth_stat value, replace the RQ_AUTHERR flag with use of that new method. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker

SUNRPC: Add svc_rqst::rq_auth_stat

2021-08-10T18:18:35+00:00

I'd like to take commit 4532608d71c8 ("SUNRPC: Clean up generic dispatcher code") even further by using only private local SVC dispatchers for all kernel RPC services. This change would enable the removal of the logic that switches between svc_generic_dispatch() and a service's private dispatcher, and simplify the invocation of the service's pc_release method so that humans can visually verify that it is always invoked properly. All that will come later. First, let's provide a better way to return authentication errors from SVC dispatcher functions. Instead of overloading the dispatch method's *statp argument, add a field to struct svc_rqst that can hold an error value. Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker

NFSD: Extract the svcxdr_init_encode() helper

2021-03-22T14:18:51+00:00

NFSD initializes an encode xdr_stream only after the RPC layer has already inserted the RPC Reply header. Thus it behaves differently than xdr_init_encode does, which assumes the passed-in xdr_buf is entirely devoid of content. nfs4proc.c has this server-side stream initialization helper, but it is visible only to the NFSv4 code. Move this helper to a place that can be accessed by NFSv2 and NFSv3 server XDR functions. Signed-off-by: Chuck Lever