linux-stable.git/net/sunrpc, branch v5.4.99

SUNRPC: Handle 0 length opaque XDR object data properly

2021-02-13T12:52:56+00:00

[ Upstream commit e4a7d1f7707eb44fd953a31dd59eff82009d879c ]

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 
Signed-off-by: Sasha Levin

SUNRPC: Move simple_get_bytes and simple_get_netobj into private header

2021-02-13T12:52:56+00:00

[ Upstream commit ba6dfce47c4d002d96cd02a304132fca76981172 ]

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 
Signed-off-by: Sasha Levin

net: sunrpc: interpret the return value of kstrtou32 correctly

2021-01-19T17:26:18+00:00

commit 86b53fbf08f48d353a86a06aef537e78e82ba721 upstream.

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 
Signed-off-by: Greg Kroah-Hartman

xprtrdma: Fix XDRBUF_SPARSE_PAGES support

2020-12-30T10:51:38+00:00

commit 15261b9126cd5bb2ad8521da49d8f5c042d904c7 upstream.

Olga K. observed that rpcrdma_marsh_req() allocates sparse pages
only when it has determined that a Reply chunk is necessary. There
are plenty of cases where no Reply chunk is needed, but the
XDRBUF_SPARSE_PAGES flag is set. The result would be a crash in
rpcrdma_inline_fixup() when it tries to copy parts of the received
Reply into a missing page.

To avoid crashing, handle sparse page allocation up front.

Until XATTR support was added, this issue did not appear often
because the only SPARSE_PAGES consumer always expected a reply large
enough to always require a Reply chunk.

Reported-by: Olga Kornievskaia 
Signed-off-by: Chuck Lever 
Cc: 
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

sunrpc: fix xs_read_xdr_buf for partial pages receive

2020-12-30T10:51:26+00:00

[ Upstream commit ac9645c87380e39a8fa87a1b51721efcdea89dbf ]

When receiving pages data, return value 'ret' when positive includes
`buf->page_base`, so we should subtract that before it is used for
changing `offset` and comparing against `want`.

This was discovered on the very rare cases where the server returned a
chunk of bytes that when added to the already received amount of bytes
for the pages happened to match the current `recv.len`, for example
on this case:

     buf->page_base : 258356
     actually received from socket: 1740
     ret : 260096
     want : 260096

In this case neither of the two 'if ... goto out' trigger, and we
continue to tail parsing.

Worth to mention that the ensuing EMSGSIZE from the continued execution of
`xs_read_xdr_buf` may be observed by an application due to 4 superfluous
bytes being added to the pages data.

Fixes: 277e4ab7d530 ("SUNRPC: Simplify TCP receive code by switching to using iterators")
Signed-off-by: Dan Aloni 
Signed-off-by: Trond Myklebust 
Signed-off-by: Sasha Levin

net: sunrpc: Fix 'snprintf' return value check in 'do_xprt_debugfs'

2020-12-30T10:51:16+00:00

[ Upstream commit 35a6d396721e28ba161595b0fc9e8896c00399bb ]

'snprintf' returns the number of characters which would have been written
if enough space had been available, excluding the terminating null byte.
Thus, the return value of 'sizeof(buf)' means that the last character
has been dropped.

Signed-off-by: Fedor Tokarev 
Fixes: 2f34b8bfae19 ("SUNRPC: add links for all client xprts to debugfs")
Signed-off-by: Trond Myklebust 
Signed-off-by: Sasha Levin

SUNRPC: xprt_load_transport() needs to support the netid "rdma6"

2020-12-30T10:51:16+00:00

[ Upstream commit d5aa6b22e2258f05317313ecc02efbb988ed6d38 ]

According to RFC5666, the correct netid for an IPv6 addressed RDMA
transport is "rdma6", which we've supported as a mount option since
Linux-4.7. The problem is when we try to load the module "xprtrdma6",
that will fail, since there is no modulealias of that name.

Fixes: 181342c5ebe8 ("xprtrdma: Add rdma6 option to support NFS/RDMA IPv6")
Signed-off-by: Trond Myklebust 
Signed-off-by: Sasha Levin

SUNRPC: rpc_wake_up() should wake up tasks in the correct order

2020-12-30T10:51:15+00:00

[ Upstream commit e4c72201b6ec3173dfe13fa2e2335a3ad78d4921 ]

Currently, we wake up the tasks by priority queue ordering, which means
that we ignore the batching that is supposed to help with QoS issues.

Fixes: c049f8ea9a0d ("SUNRPC: Remove the bh-safe lock requirement on the rpc_wait_queue->lock")
Signed-off-by: Trond Myklebust 
Signed-off-by: Sasha Levin

SUNRPC: Mitigate cond_resched() in xprt_transmit()

2020-11-05T10:43:18+00:00

[ Upstream commit 6f9f17287e78e5049931af2037b15b26d134a32a ]

The original purpose of this expensive call is to prevent a long
queue of requests from blocking other work.

The cond_resched() call is unnecessary after just a single send
operation.

For longer queues, instead of invoking the kernel scheduler, simply
release the transport send lock and return to the RPC scheduler.

Signed-off-by: Chuck Lever 
Signed-off-by: Anna Schumaker 
Signed-off-by: Sasha Levin

SUNRPC: fix copying of multiple pages in gss_read_proxy_verf()

2020-10-29T08:57:56+00:00

[ Upstream commit d48c8124749c9a5081fe68680f83605e272c984b ]

When the passed token is longer than 4032 bytes, the remaining part
of the token must be copied from the rqstp->rq_arg.pages. But the
copy must make sure it happens in a consecutive way.

With the existing code, the first memcpy copies 'length' bytes from
argv->iobase, but since the header is in front, this never fills the
whole first page of in_token->pages.

The mecpy in the loop copies the following bytes, but starts writing at
the next page of in_token->pages.  This leaves the last bytes of page 0
unwritten.

Symptoms were that users with many groups were not able to access NFS
exports, when using Active Directory as the KDC.

Signed-off-by: Martijn de Gouw 
Fixes: 5866efa8cbfb "SUNRPC: Fix svcauth_gss_proxy_init()"
Signed-off-by: J. Bruce Fields 
Signed-off-by: Sasha Levin