kernel/linux.git/include/linux/sunrpc, branch v5.15.97

SUNRPC: ensure the matching upcall is in-flight upon downcall

2023-01-12T10:59:08+00:00

[ Upstream commit b18cba09e374637a0a3759d856a6bca94c133952 ] Commit 9130b8dbc6ac ("SUNRPC: allow for upcalls for the same uid but different gss service") introduced `auth` argument to __gss_find_upcall(), but in gss_pipe_downcall() it was left as NULL since it (and auth->service) was not (yet) determined. When multiple upcalls with the same uid and different service are ongoing, it could happen that __gss_find_upcall(), which returns the first match found in the pipe->in_downcall list, could not find the correct gss_msg corresponding to the downcall we are looking for. Moreover, it might return a msg which is not sent to rpc.gssd yet. We could see mount.nfs process hung in D state with multiple mount.nfs are executed in parallel. The call trace below is of CentOS 7.9 kernel-3.10.0-1160.24.1.el7.x86_64 but we observed the same hang w/ elrepo kernel-ml-6.0.7-1.el7. PID: 71258 TASK: ffff91ebd4be0000 CPU: 36 COMMAND: "mount.nfs" #0 [ffff9203ca3234f8] __schedule at ffffffffa3b8899f #1 [ffff9203ca323580] schedule at ffffffffa3b88eb9 #2 [ffff9203ca323590] gss_cred_init at ffffffffc0355818 [auth_rpcgss] #3 [ffff9203ca323658] rpcauth_lookup_credcache at ffffffffc0421ebc [sunrpc] #4 [ffff9203ca3236d8] gss_lookup_cred at ffffffffc0353633 [auth_rpcgss] #5 [ffff9203ca3236e8] rpcauth_lookupcred at ffffffffc0421581 [sunrpc] #6 [ffff9203ca323740] rpcauth_refreshcred at ffffffffc04223d3 [sunrpc] #7 [ffff9203ca3237a0] call_refresh at ffffffffc04103dc [sunrpc] #8 [ffff9203ca3237b8] __rpc_execute at ffffffffc041e1c9 [sunrpc] #9 [ffff9203ca323820] rpc_execute at ffffffffc0420a48 [sunrpc] The scenario is like this. Let's say there are two upcalls for services A and B, A -> B in pipe->in_downcall, B -> A in pipe->pipe. When rpc.gssd reads pipe to get the upcall msg corresponding to service B from pipe->pipe and then writes the response, in gss_pipe_downcall the msg corresponding to service A will be picked because only uid is used to find the msg and it is before the one for B in pipe->in_downcall. And the process waiting for the msg corresponding to service A will be woken up. Actual scheduing of that process might be after rpc.gssd processes the next msg. In rpc_pipe_generic_upcall it clears msg->errno (for A). The process is scheduled to see gss_msg->ctx == NULL and gss_msg->msg.errno == 0, therefore it cannot break the loop in gss_create_upcall and is never woken up after that. This patch adds a simple check to ensure that a msg which is not sent to rpc.gssd yet is not chosen as the matching upcall upon receiving a downcall. Signed-off-by: minoura makoto Signed-off-by: Hiroshi Shimamoto Tested-by: Hiroshi Shimamoto Cc: Trond Myklebust Fixes: 9130b8dbc6ac ("SUNRPC: allow for upcalls for same uid but different gss service") Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin

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 xdr_encode_bool()

2022-08-25T09:40:05+00:00

commit c770f31d8f580ed4b965c64f924ec1cc50e41734 upstream. I discovered that xdr_encode_bool() was returning the same address that was passed in the @p parameter. The documenting comment states that the intent is to return the address of the next buffer location, just like the other "xdr_encode_*" helpers. The result was the encoded results of NFSv3 PATHCONF operations were not formed correctly. Fixes: ded04a587f6c ("NFSD: Update the NFSv3 PATHCONF3res encoder to use struct xdr_stream") Signed-off-by: Chuck Lever Reviewed-by: Jeff Layton Signed-off-by: Greg Kroah-Hartman

SUNRPC: Ensure that the gssproxy client can start in a connected state

2022-05-18T08:26:56+00:00

commit fd13359f54ee854f00134abc6be32da94ec53dbf upstream. Ensure that the gssproxy client connects to the server from the gssproxy daemon process context so that the AF_LOCAL socket connection is done using the correct path and namespaces. Fixes: 1d658336b05f ("SUNRPC: Add RPC based upcall mechanism for RPCGSS auth") Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman

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

SUNRPC: Don't call connect() more than once on a TCP socket

2022-04-13T18:59:26+00:00

commit 89f42494f92f448747bd8a7ab1ae8b5d5520577d upstream. Avoid socket state races due to repeated calls to ->connect() using the same socket. If connect() returns 0 due to the connection having completed, but we are in fact in a closing state, then we may leave the XPRT_CONNECTING flag set on the transport. Reported-by: Enrico Scholz Fixes: 3be232f11a3c ("SUNRPC: Prevent immediate close+reconnect") Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman

NFSD: prevent integer overflow on 32 bit systems

2022-04-08T12:22:52+00:00

commit 23a9dbbe0faf124fc4c139615633b9d12a3a89ef upstream. On a 32 bit system, the "len * sizeof(*p)" operation can have an integer overflow. Cc: stable@vger.kernel.org Signed-off-by: Dan Carpenter Signed-off-by: Chuck Lever 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() ...