linux-stable.git/net/sunrpc, branch v5.11

SUNRPC: Fix NFS READs that start at non-page-aligned offsets

2021-02-01T15:03:51+00:00

Anj Duvnjak reports that the Kodi.tv NFS client is not able to read
video files from a v5.10.11 Linux NFS server.

The new sendpage-based TCP sendto logic was not attentive to non-
zero page_base values. nfsd_splice_read() sets that field when a
READ payload starts in the middle of a page.

The Linux NFS client rarely emits an NFS READ that is not page-
aligned. All of my testing so far has been with Linux clients, so I
missed this one.

Reported-by: A. Duvnjak 
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=211471
Fixes: 4a85a6a3320b ("SUNRPC: Handle TCP socket sends with kernel_sendpage() again")
Signed-off-by: Chuck Lever 
Tested-by: A. Duvnjak

SUNRPC: Handle 0 length opaque XDR object data properly

2021-01-25T20:59:12+00:00

When handling an auth_gss downcall, it's possible to get 0-length
opaque object for the acceptor.  In the case of a 0-length XDR
object, make sure simple_get_netobj() fills in dest->data = NULL,
and does not continue to kmemdup() which will set
dest->data = ZERO_SIZE_PTR for the acceptor.

The trace event code can handle NULL but not ZERO_SIZE_PTR for a
string, and so without this patch the rpcgss_context trace event
will crash the kernel as follows:

[  162.887992] BUG: kernel NULL pointer dereference, address: 0000000000000010
[  162.898693] #PF: supervisor read access in kernel mode
[  162.900830] #PF: error_code(0x0000) - not-present page
[  162.902940] PGD 0 P4D 0
[  162.904027] Oops: 0000 [#1] SMP PTI
[  162.905493] CPU: 4 PID: 4321 Comm: rpc.gssd Kdump: loaded Not tainted 5.10.0 #133
[  162.908548] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[  162.910978] RIP: 0010:strlen+0x0/0x20
[  162.912505] Code: 48 89 f9 74 09 48 83 c1 01 80 39 00 75 f7 31 d2 44 0f b6 04 16 44 88 04 11 48 83 c2 01 45 84 c0 75 ee c3 0f 1f 80 00 00 00 00 <80> 3f 00 74 10 48 89 f8 48 83 c0 01 80 38 00 75 f7 48 29 f8 c3 31
[  162.920101] RSP: 0018:ffffaec900c77d90 EFLAGS: 00010202
[  162.922263] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00000000fffde697
[  162.925158] RDX: 000000000000002f RSI: 0000000000000080 RDI: 0000000000000010
[  162.928073] RBP: 0000000000000010 R08: 0000000000000e10 R09: 0000000000000000
[  162.930976] R10: ffff8e698a590cb8 R11: 0000000000000001 R12: 0000000000000e10
[  162.933883] R13: 00000000fffde697 R14: 000000010034d517 R15: 0000000000070028
[  162.936777] FS:  00007f1e1eb93700(0000) GS:ffff8e6ab7d00000(0000) knlGS:0000000000000000
[  162.940067] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  162.942417] CR2: 0000000000000010 CR3: 0000000104eba000 CR4: 00000000000406e0
[  162.945300] Call Trace:
[  162.946428]  trace_event_raw_event_rpcgss_context+0x84/0x140 [auth_rpcgss]
[  162.949308]  ? __kmalloc_track_caller+0x35/0x5a0
[  162.951224]  ? gss_pipe_downcall+0x3a3/0x6a0 [auth_rpcgss]
[  162.953484]  gss_pipe_downcall+0x585/0x6a0 [auth_rpcgss]
[  162.955953]  rpc_pipe_write+0x58/0x70 [sunrpc]
[  162.957849]  vfs_write+0xcb/0x2c0
[  162.959264]  ksys_write+0x68/0xe0
[  162.960706]  do_syscall_64+0x33/0x40
[  162.962238]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  162.964346] RIP: 0033:0x7f1e1f1e57df

Signed-off-by: Dave Wysochanski 
Signed-off-by: Trond Myklebust

SUNRPC: Move simple_get_bytes and simple_get_netobj into private header

2021-01-25T20:59:12+00:00

Remove duplicated helper functions to parse opaque XDR objects
and place inside new file net/sunrpc/auth_gss/auth_gss_internal.h.
In the new file carry the license and copyright from the source file
net/sunrpc/auth_gss/auth_gss.c.  Finally, update the comment inside
include/linux/sunrpc/xdr.h since lockd is not the only user of
struct xdr_netobj.

Signed-off-by: Dave Wysochanski 
Signed-off-by: Trond Myklebust

Merge tag 'nfsd-5.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

2021-01-19T21:01:50+00:00

Pull nfsd fixes from Chuck Lever:

 - Avoid exposing parent of root directory in NFSv3 READDIRPLUS results

 - Fix a tracepoint change that went in the initial 5.11 merge

* tag 'nfsd-5.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  SUNRPC: Move the svc_xdr_recvfrom tracepoint again
  nfsd4: readdirplus shouldn't return parent of export

SUNRPC: Move the svc_xdr_recvfrom tracepoint again

2021-01-13T14:13:20+00:00

Commit 156708adf2d9 ("SUNRPC: Move the svc_xdr_recvfrom()
tracepoint") tried to capture the correct XID in the trace record,
but this line in svc_recv:

	rqstp->rq_xid = svc_getu32(&rqstp->rq_arg.head[0]);

alters the size of rq_arg.head[0].iov_len. The tracepoint records
the correct XID but an incorrect value for the length of the
xdr_buf's head.

To keep the trace callsites simple, I've created two trace classes.
One assumes the xdr_buf contains a full RPC message, and the XID
can be extracted from it. The other assumes the contents of the
xdr_buf are arbitrary, and the xid will be provided by the caller.

Currently there is only one user of each class, but I expect we will
need a few more tracepoints using each class as time goes on.

Signed-off-by: Chuck Lever

Merge tag 'nfs-for-5.11-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2021-01-12T17:38:53+00:00

Pull NFS client fixes from Trond Myklebust:
 "Highlights include:

   - Fix parsing of link-local IPv6 addresses

   - Fix confusing logging of mount errors that was introduced by the
     fsopen() patchset.

   - Fix a tracing use after free in _nfs4_do_setlk()

   - Layout return-on-close fixes when called from nfs4_evict_inode()

   - Layout segments were being leaked in
     pnfs_generic_clear_request_commit()

   - Don't leak DS commits in pnfs_generic_retry_commit()

   - Fix an Oopsable use-after-free when nfs_delegation_find_inode_server()
     calls iput() on an inode after the super block has gone away"

* tag 'nfs-for-5.11-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS: nfs_igrab_and_active must first reference the superblock
  NFS: nfs_delegation_find_inode_server must first reference the superblock
  NFS/pNFS: Fix a leak of the layout 'plh_outstanding' counter
  NFS/pNFS: Don't leak DS commits in pnfs_generic_retry_commit()
  NFS/pNFS: Don't call pnfs_free_bucket_lseg() before removing the request
  pNFS: Stricter ordering of layoutget and layoutreturn
  pNFS: Clean up pnfs_layoutreturn_free_lsegs()
  pNFS: We want return-on-close to complete when evicting the inode
  pNFS: Mark layout for return if return-on-close was not sent
  net: sunrpc: interpret the return value of kstrtou32 correctly
  NFS: Adjust fs_context error logging
  NFS4: Fix use-after-free in trace_event_raw_event_nfs4_set_lock

Merge tag 'nfsd-5.11-1' of git://git.linux-nfs.org/projects/cel/cel-2.6

2021-01-11T19:35:46+00:00

Pull nfsd fixes from Chuck Lever:

 - Fix major TCP performance regression

 - Get NFSv4.2 READ_PLUS regression tests to pass

 - Improve NFSv4 COMPOUND memory allocation

 - Fix sparse warning

* tag 'nfsd-5.11-1' of git://git.linux-nfs.org/projects/cel/cel-2.6:
  NFSD: Restore NFSv4 decoding's SAVEMEM functionality
  SUNRPC: Handle TCP socket sends with kernel_sendpage() again
  NFSD: Fix sparse warning in nfssvc.c
  nfsd: Don't set eof on a truncated READ_PLUS
  nfsd: Fixes for nfsd4_encode_read_plus_data()

net: sunrpc: interpret the return value of kstrtou32 correctly

2021-01-10T18:32:51+00:00

A return value of 0 means success. This is documented in lib/kstrtox.c.

This was found by trying to mount an NFS share from a link-local IPv6
address with the interface specified by its index:

  mount("[fe80::1%1]:/srv/nfs", "/mnt", "nfs", 0, "nolock,addr=fe80::1%1")

Before this commit this failed with EINVAL and also caused the following
message in dmesg:

  [...] NFS: bad IP address specified: addr=fe80::1%1

The syscall using the same address based on the interface name instead
of its index succeeds.

Credits for this patch go to my colleague Christian Speich, who traced
the origin of this bug to this line of code.

Signed-off-by: Johannes Nixdorf 
Fixes: 00cfaa943ec3 ("replace strict_strto calls")
Signed-off-by: Trond Myklebust

SUNRPC: Handle TCP socket sends with kernel_sendpage() again

2020-12-18T17:28:41+00:00

Daire Byrne reports a ~50% aggregrate throughput regression on his
Linux NFS server after commit da1661b93bf4 ("SUNRPC: Teach server to
use xprt_sock_sendmsg for socket sends"), which replaced
kernel_send_page() calls in NFSD's socket send path with calls to
sock_sendmsg() using iov_iter.

Investigation showed that tcp_sendmsg() was not using zero-copy to
send the xdr_buf's bvec pages, but instead was relying on memcpy.
This means copying every byte of a large NFS READ payload.

It looks like TLS sockets do indeed support a ->sendpage method,
so it's really not necessary to use xprt_sock_sendmsg() to support
TLS fully on the server. A mechanical reversion of da1661b93bf4 is
not possible at this point, but we can re-implement the server's
TCP socket sendmsg path using kernel_sendpage().

Reported-by: Daire Byrne 
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=209439
Signed-off-by: Chuck Lever

Merge tag 'nfs-for-5.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2020-12-17T20:15:03+00:00

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
  ...