513 Commits

Author SHA1 Message Date
David Howells
c36782a0c9 rxrpc: Fix server keyring leak
[ Upstream commit 38b1dc47a35ba14c3f4472138ea56d014c2d609b ]

If someone calls setsockopt() twice to set a server key keyring, the first
keyring is leaked.

Fix it to return an error instead if the server key keyring is already set.

Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-14 09:51:14 +02:00
David Howells
c11f690471 rxrpc: Fix some missing _bh annotations on locking conn->state_lock
[ Upstream commit fa1d113a0f96f9ab7e4fe4f8825753ba1e34a9d3 ]

conn->state_lock may be taken in softirq mode, but a previous patch
replaced an outer lock in the response-packet event handling code, and lost
the _bh from that when doing so.

Fix this by applying the _bh annotation to the state_lock locking.

Fixes: a1399f8bb033 ("rxrpc: Call channels should have separate call number spaces")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-14 09:51:14 +02:00
David Howells
690a6ce474 rxrpc: Downgrade the BUG() for unsupported token type in rxrpc_read()
[ Upstream commit 9a059cd5ca7d9c5c4ca5a6e755cf72f230176b6a ]

If rxrpc_read() (which allows KEYCTL_READ to read a key), sees a token of a
type it doesn't recognise, it can BUG in a couple of places, which is
unnecessary as it can easily get back to userspace.

Fix this to print an error message instead.

Fixes: 99455153d067 ("RxRPC: Parse security index 5 keys (Kerberos 5)")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-14 09:51:14 +02:00
Marc Dionne
a9fe24352d rxrpc: Fix rxkad token xdr encoding
[ Upstream commit 56305118e05b2db8d0395bba640ac9a3aee92624 ]

The session key should be encoded with just the 8 data bytes and
no length; ENCODE_DATA precedes it with a 4 byte length, which
confuses some existing tools that try to parse this format.

Add an ENCODE_BYTES macro that does not include a length, and use
it for the key.  Also adjust the expected length.

Note that commit 774521f353e1d ("rxrpc: Fix an assertion in
rxrpc_read()") had fixed a BUG by changing the length rather than
fixing the encoding.  The original length was correct.

Fixes: 99455153d067 ("RxRPC: Parse security index 5 keys (Kerberos 5)")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-14 09:51:13 +02:00
David Howells
6aa01b947c rxrpc: Fix race between recvmsg and sendmsg on immediate call failure
[ Upstream commit 65550098c1c4db528400c73acf3e46bfa78d9264 ]

There's a race between rxrpc_sendmsg setting up a call, but then failing to
send anything on it due to an error, and recvmsg() seeing the call
completion occur and trying to return the state to the user.

An assertion fails in rxrpc_recvmsg() because the call has already been
released from the socket and is about to be released again as recvmsg deals
with it.  (The recvmsg_q queue on the socket holds a ref, so there's no
problem with use-after-free.)

We also have to be careful not to end up reporting an error twice, in such
a way that both returns indicate to userspace that the user ID supplied
with the call is no longer in use - which could cause the client to
malfunction if it recycles the user ID fast enough.

Fix this by the following means:

 (1) When sendmsg() creates a call after the point that the call has been
     successfully added to the socket, don't return any errors through
     sendmsg(), but rather complete the call and let recvmsg() retrieve
     them.  Make sendmsg() return 0 at this point.  Further calls to
     sendmsg() for that call will fail with ESHUTDOWN.

     Note that at this point, we haven't send any packets yet, so the
     server doesn't yet know about the call.

 (2) If sendmsg() returns an error when it was expected to create a new
     call, it means that the user ID wasn't used.

 (3) Mark the call disconnected before marking it completed to prevent an
     oops in rxrpc_release_call().

 (4) recvmsg() will then retrieve the error and set MSG_EOR to indicate
     that the user ID is no longer known by the kernel.

An oops like the following is produced:

	kernel BUG at net/rxrpc/recvmsg.c:605!
	...
	RIP: 0010:rxrpc_recvmsg+0x256/0x5ae
	...
	Call Trace:
	 ? __init_waitqueue_head+0x2f/0x2f
	 ____sys_recvmsg+0x8a/0x148
	 ? import_iovec+0x69/0x9c
	 ? copy_msghdr_from_user+0x5c/0x86
	 ___sys_recvmsg+0x72/0xaa
	 ? __fget_files+0x22/0x57
	 ? __fget_light+0x46/0x51
	 ? fdget+0x9/0x1b
	 do_recvmmsg+0x15e/0x232
	 ? _raw_spin_unlock+0xa/0xb
	 ? vtime_delta+0xf/0x25
	 __x64_sys_recvmmsg+0x2c/0x2f
	 do_syscall_64+0x4c/0x78
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 357f5ef64628 ("rxrpc: Call rxrpc_release_call() on error in rxrpc_new_client_call()")
Reported-by: syzbot+b54969381df354936d96@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21 09:48:02 +02:00
David Howells
88fb6b3913 rxrpc: Fix sendmsg() returning EPIPE due to recvmsg() returning ENODATA
[ Upstream commit 639f181f0ee20d3249dbc55f740f0167267180f0 ]

rxrpc_sendmsg() returns EPIPE if there's an outstanding error, such as if
rxrpc_recvmsg() indicating ENODATA if there's nothing for it to read.

Change rxrpc_recvmsg() to return EAGAIN instead if there's nothing to read
as this particular error doesn't get stored in ->sk_err by the networking
core.

Also change rxrpc_sendmsg() so that it doesn't fail with delayed receive
errors (there's no way for it to report which call, if any, the error was
caused by).

Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-31 16:44:44 +02:00
David Howells
9cdc893472 rxrpc: Fix handling of rwind from an ACK packet
[ Upstream commit a2ad7c21ad8cf1ce4ad65e13df1c2a1c29b38ac5 ]

The handling of the receive window size (rwind) from a received ACK packet
is not correct.  The rxrpc_input_ackinfo() function currently checks the
current Tx window size against the rwind from the ACK to see if it has
changed, but then limits the rwind size before storing it in the tx_winsize
member and, if it increased, wake up the transmitting process.  This means
that if rwind > RXRPC_RXTX_BUFF_SIZE - 1, this path will always be
followed.

Fix this by limiting rwind before we compare it to tx_winsize.

The effect of this can be seen by enabling the rxrpc_rx_rwind_change
tracepoint.

Fixes: 702f2ac87a9a ("rxrpc: Wake up the transmitter if Rx window size increases on the peer")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 15:38:04 -04:00
David Howells
ca03a5c2e7 rxrpc: Fix notification call on completion of discarded calls
[ Upstream commit 0041cd5a50442db6e456b145892a0eaf2dff061f ]

When preallocated service calls are being discarded, they're passed to
->discard_new_call() to have the caller clean up any attached higher-layer
preallocated pieces before being marked completed.  However, the act of
marking them completed now invokes the call's notification function - which
causes a problem because that function might assume that the previously
freed pieces of memory are still there.

Fix this by setting a dummy notification function on the socket after
calling ->discard_new_call().

This results in the following kasan message when the kafs module is
removed.

==================================================================
BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 fs/afs/rxrpc.c:707
Write of size 1 at addr ffff8880946c39e4 by task kworker/u4:1/21

CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 afs_wake_up_async_call+0x6aa/0x770 fs/afs/rxrpc.c:707
 rxrpc_notify_socket+0x1db/0x5d0 net/rxrpc/recvmsg.c:40
 __rxrpc_set_call_completion.part.0+0x172/0x410 net/rxrpc/recvmsg.c:76
 __rxrpc_call_completed net/rxrpc/recvmsg.c:112 [inline]
 rxrpc_call_completed+0xca/0xf0 net/rxrpc/recvmsg.c:111
 rxrpc_discard_prealloc+0x781/0xab0 net/rxrpc/call_accept.c:233
 rxrpc_listen+0x147/0x360 net/rxrpc/af_rxrpc.c:245
 afs_close_socket+0x95/0x320 fs/afs/rxrpc.c:110
 afs_net_exit+0x1bc/0x310 fs/afs/main.c:155
 ops_exit_list.isra.0+0xa8/0x150 net/core/net_namespace.c:186
 cleanup_net+0x511/0xa50 net/core/net_namespace.c:603
 process_one_work+0x965/0x1690 kernel/workqueue.c:2269
 worker_thread+0x96/0xe10 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:291
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293

Allocated by task 6820:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc mm/kasan/common.c:494 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:467
 kmem_cache_alloc_trace+0x153/0x7d0 mm/slab.c:3551
 kmalloc include/linux/slab.h:555 [inline]
 kzalloc include/linux/slab.h:669 [inline]
 afs_alloc_call+0x55/0x630 fs/afs/rxrpc.c:141
 afs_charge_preallocation+0xe9/0x2d0 fs/afs/rxrpc.c:757
 afs_open_socket+0x292/0x360 fs/afs/rxrpc.c:92
 afs_net_init+0xa6c/0xe30 fs/afs/main.c:125
 ops_init+0xaf/0x420 net/core/net_namespace.c:151
 setup_net+0x2de/0x860 net/core/net_namespace.c:341
 copy_net_ns+0x293/0x590 net/core/net_namespace.c:482
 create_new_namespaces+0x3fb/0xb30 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:231
 ksys_unshare+0x43d/0x8e0 kernel/fork.c:2983
 __do_sys_unshare kernel/fork.c:3051 [inline]
 __se_sys_unshare kernel/fork.c:3049 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3049
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 21:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 kasan_set_free_info mm/kasan/common.c:316 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:455
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x109/0x2b0 mm/slab.c:3757
 afs_put_call+0x585/0xa40 fs/afs/rxrpc.c:190
 rxrpc_discard_prealloc+0x764/0xab0 net/rxrpc/call_accept.c:230
 rxrpc_listen+0x147/0x360 net/rxrpc/af_rxrpc.c:245
 afs_close_socket+0x95/0x320 fs/afs/rxrpc.c:110
 afs_net_exit+0x1bc/0x310 fs/afs/main.c:155
 ops_exit_list.isra.0+0xa8/0x150 net/core/net_namespace.c:186
 cleanup_net+0x511/0xa50 net/core/net_namespace.c:603
 process_one_work+0x965/0x1690 kernel/workqueue.c:2269
 worker_thread+0x96/0xe10 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:291
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293

The buggy address belongs to the object at ffff8880946c3800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 484 bytes inside of
 1024-byte region [ffff8880946c3800, ffff8880946c3c00)
The buggy address belongs to the page:
page:ffffea000251b0c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea0002546508 ffffea00024fa248 ffff8880aa000c40
raw: 0000000000000000 ffff8880946c3000 0000000100000002 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880946c3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880946c3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880946c3980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff8880946c3a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880946c3a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Reported-by: syzbot+d3eccef36ddbd02713e9@syzkaller.appspotmail.com
Fixes: 5ac0d62226a0 ("rxrpc: Fix missing notification")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:37:59 -04:00
David Howells
c1bc642250 rxrpc: Fix transport sockopts to get IPv4 errors on an IPv6 socket
commit 37a675e768d7606fe8a53e0c459c9b53e121ac20 upstream.

It seems that enabling IPV6_RECVERR on an IPv6 socket doesn't also turn on
IP_RECVERR, so neither local errors nor ICMP-transported remote errors from
IPv4 peer addresses are returned to the AF_RXRPC protocol.

Make the sockopt setting code in rxrpc_open_socket() fall through from the
AF_INET6 case to the AF_INET case to turn on all the AF_INET options too in
the AF_INET6 case.

Fixes: f2aeed3a591f ("rxrpc: Fix error reception on AF_INET6 sockets")
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-03 08:18:11 +02:00
Qiushi Wu
4cb6b5c57e rxrpc: Fix a memory leak in rxkad_verify_response()
commit f45d01f4f30b53c3a0a1c6c1c154acb7ff74ab9f upstream.

A ticket was not released after a call of the function
"rxkad_decrypt_ticket" failed. Thus replace the jump target
"temporary_error_free_resp" by "temporary_error_free_ticket".

Fixes: 8c2f826dc3631 ("rxrpc: Don't put crypto buffers on the stack")
Signed-off-by: Qiushi Wu <wu000273@umn.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Markus Elfring <Markus.Elfring@web.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 16:43:12 +02:00
Waiman Long
7fa67aa305 KEYS: Don't write out to userspace while holding key semaphore
commit d3ec10aa95819bff18a0d936b18884c7816d0914 upstream.

A lockdep circular locking dependency report was seen when running a
keyutils test:

[12537.027242] ======================================================
[12537.059309] WARNING: possible circular locking dependency detected
[12537.088148] 4.18.0-147.7.1.el8_1.x86_64+debug #1 Tainted: G OE    --------- -  -
[12537.125253] ------------------------------------------------------
[12537.153189] keyctl/25598 is trying to acquire lock:
[12537.175087] 000000007c39f96c (&mm->mmap_sem){++++}, at: __might_fault+0xc4/0x1b0
[12537.208365]
[12537.208365] but task is already holding lock:
[12537.234507] 000000003de5b58d (&type->lock_class){++++}, at: keyctl_read_key+0x15a/0x220
[12537.270476]
[12537.270476] which lock already depends on the new lock.
[12537.270476]
[12537.307209]
[12537.307209] the existing dependency chain (in reverse order) is:
[12537.340754]
[12537.340754] -> #3 (&type->lock_class){++++}:
[12537.367434]        down_write+0x4d/0x110
[12537.385202]        __key_link_begin+0x87/0x280
[12537.405232]        request_key_and_link+0x483/0xf70
[12537.427221]        request_key+0x3c/0x80
[12537.444839]        dns_query+0x1db/0x5a5 [dns_resolver]
[12537.468445]        dns_resolve_server_name_to_ip+0x1e1/0x4d0 [cifs]
[12537.496731]        cifs_reconnect+0xe04/0x2500 [cifs]
[12537.519418]        cifs_readv_from_socket+0x461/0x690 [cifs]
[12537.546263]        cifs_read_from_socket+0xa0/0xe0 [cifs]
[12537.573551]        cifs_demultiplex_thread+0x311/0x2db0 [cifs]
[12537.601045]        kthread+0x30c/0x3d0
[12537.617906]        ret_from_fork+0x3a/0x50
[12537.636225]
[12537.636225] -> #2 (root_key_user.cons_lock){+.+.}:
[12537.664525]        __mutex_lock+0x105/0x11f0
[12537.683734]        request_key_and_link+0x35a/0xf70
[12537.705640]        request_key+0x3c/0x80
[12537.723304]        dns_query+0x1db/0x5a5 [dns_resolver]
[12537.746773]        dns_resolve_server_name_to_ip+0x1e1/0x4d0 [cifs]
[12537.775607]        cifs_reconnect+0xe04/0x2500 [cifs]
[12537.798322]        cifs_readv_from_socket+0x461/0x690 [cifs]
[12537.823369]        cifs_read_from_socket+0xa0/0xe0 [cifs]
[12537.847262]        cifs_demultiplex_thread+0x311/0x2db0 [cifs]
[12537.873477]        kthread+0x30c/0x3d0
[12537.890281]        ret_from_fork+0x3a/0x50
[12537.908649]
[12537.908649] -> #1 (&tcp_ses->srv_mutex){+.+.}:
[12537.935225]        __mutex_lock+0x105/0x11f0
[12537.954450]        cifs_call_async+0x102/0x7f0 [cifs]
[12537.977250]        smb2_async_readv+0x6c3/0xc90 [cifs]
[12538.000659]        cifs_readpages+0x120a/0x1e50 [cifs]
[12538.023920]        read_pages+0xf5/0x560
[12538.041583]        __do_page_cache_readahead+0x41d/0x4b0
[12538.067047]        ondemand_readahead+0x44c/0xc10
[12538.092069]        filemap_fault+0xec1/0x1830
[12538.111637]        __do_fault+0x82/0x260
[12538.129216]        do_fault+0x419/0xfb0
[12538.146390]        __handle_mm_fault+0x862/0xdf0
[12538.167408]        handle_mm_fault+0x154/0x550
[12538.187401]        __do_page_fault+0x42f/0xa60
[12538.207395]        do_page_fault+0x38/0x5e0
[12538.225777]        page_fault+0x1e/0x30
[12538.243010]
[12538.243010] -> #0 (&mm->mmap_sem){++++}:
[12538.267875]        lock_acquire+0x14c/0x420
[12538.286848]        __might_fault+0x119/0x1b0
[12538.306006]        keyring_read_iterator+0x7e/0x170
[12538.327936]        assoc_array_subtree_iterate+0x97/0x280
[12538.352154]        keyring_read+0xe9/0x110
[12538.370558]        keyctl_read_key+0x1b9/0x220
[12538.391470]        do_syscall_64+0xa5/0x4b0
[12538.410511]        entry_SYSCALL_64_after_hwframe+0x6a/0xdf
[12538.435535]
[12538.435535] other info that might help us debug this:
[12538.435535]
[12538.472829] Chain exists of:
[12538.472829]   &mm->mmap_sem --> root_key_user.cons_lock --> &type->lock_class
[12538.472829]
[12538.524820]  Possible unsafe locking scenario:
[12538.524820]
[12538.551431]        CPU0                    CPU1
[12538.572654]        ----                    ----
[12538.595865]   lock(&type->lock_class);
[12538.613737]                                lock(root_key_user.cons_lock);
[12538.644234]                                lock(&type->lock_class);
[12538.672410]   lock(&mm->mmap_sem);
[12538.687758]
[12538.687758]  *** DEADLOCK ***
[12538.687758]
[12538.714455] 1 lock held by keyctl/25598:
[12538.732097]  #0: 000000003de5b58d (&type->lock_class){++++}, at: keyctl_read_key+0x15a/0x220
[12538.770573]
[12538.770573] stack backtrace:
[12538.790136] CPU: 2 PID: 25598 Comm: keyctl Kdump: loaded Tainted: G
[12538.844855] Hardware name: HP ProLiant DL360 Gen9/ProLiant DL360 Gen9, BIOS P89 12/27/2015
[12538.881963] Call Trace:
[12538.892897]  dump_stack+0x9a/0xf0
[12538.907908]  print_circular_bug.isra.25.cold.50+0x1bc/0x279
[12538.932891]  ? save_trace+0xd6/0x250
[12538.948979]  check_prev_add.constprop.32+0xc36/0x14f0
[12538.971643]  ? keyring_compare_object+0x104/0x190
[12538.992738]  ? check_usage+0x550/0x550
[12539.009845]  ? sched_clock+0x5/0x10
[12539.025484]  ? sched_clock_cpu+0x18/0x1e0
[12539.043555]  __lock_acquire+0x1f12/0x38d0
[12539.061551]  ? trace_hardirqs_on+0x10/0x10
[12539.080554]  lock_acquire+0x14c/0x420
[12539.100330]  ? __might_fault+0xc4/0x1b0
[12539.119079]  __might_fault+0x119/0x1b0
[12539.135869]  ? __might_fault+0xc4/0x1b0
[12539.153234]  keyring_read_iterator+0x7e/0x170
[12539.172787]  ? keyring_read+0x110/0x110
[12539.190059]  assoc_array_subtree_iterate+0x97/0x280
[12539.211526]  keyring_read+0xe9/0x110
[12539.227561]  ? keyring_gc_check_iterator+0xc0/0xc0
[12539.249076]  keyctl_read_key+0x1b9/0x220
[12539.266660]  do_syscall_64+0xa5/0x4b0
[12539.283091]  entry_SYSCALL_64_after_hwframe+0x6a/0xdf

One way to prevent this deadlock scenario from happening is to not
allow writing to userspace while holding the key semaphore. Instead,
an internal buffer is allocated for getting the keys out from the
read method first before copying them out to userspace without holding
the lock.

That requires taking out the __user modifier from all the relevant
read methods as well as additional changes to not use any userspace
write helpers. That is,

  1) The put_user() call is replaced by a direct copy.
  2) The copy_to_user() call is replaced by memcpy().
  3) All the fault handling code is removed.

Compiling on a x86-64 system, the size of the rxrpc_read() function is
reduced from 3795 bytes to 2384 bytes with this patch.

Fixes: ^1da177e4c3f4 ("Linux-2.6.12-rc2")
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 08:01:25 +02:00
David Howells
c12b8cb9f1 rxrpc: Fix service call disconnection
[ Upstream commit b39a934ec72fa2b5a74123891f25273a38378b90 ]

The recent patch that substituted a flag on an rxrpc_call for the
connection pointer being NULL as an indication that a call was disconnected
puts the set_bit in the wrong place for service calls.  This is only a
problem if a call is implicitly terminated by a new call coming in on the
same connection channel instead of a terminating ACK packet.

In such a case, rxrpc_input_implicit_end_call() calls
__rxrpc_disconnect_call(), which is now (incorrectly) setting the
disconnection bit, meaning that when rxrpc_release_call() is later called,
it doesn't call rxrpc_disconnect_call() and so the call isn't removed from
the peer's error distribution list and the list gets corrupted.

KASAN finds the issue as an access after release on a call, but the
position at which it occurs is confusing as it appears to be related to a
different call (the call site is where the latter call is being removed
from the error distribution list and either the next or pprev pointer
points to a previously released call).

Fix this by moving the setting of the flag from __rxrpc_disconnect_call()
to rxrpc_disconnect_call() in the same place that the connection pointer
was being cleared.

Fixes: 5273a191dca6 ("rxrpc: Fix NULL pointer deref due to call->conn being cleared on disconnect")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-14 16:32:21 -05:00
David Howells
3740a6078d rxrpc: Fix NULL pointer deref due to call->conn being cleared on disconnect
[ Upstream commit 5273a191dca65a675dc0bcf3909e59c6933e2831 ]

When a call is disconnected, the connection pointer from the call is
cleared to make sure it isn't used again and to prevent further attempted
transmission for the call.  Unfortunately, there might be a daemon trying
to use it at the same time to transmit a packet.

Fix this by keeping call->conn set, but setting a flag on the call to
indicate disconnection instead.

Remove also the bits in the transmission functions where the conn pointer is
checked and a ref taken under spinlock as this is now redundant.

Fixes: 8d94aa381dab ("rxrpc: Calls shouldn't hold socket refs")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:32:07 -05:00
David Howells
532e2558e5 rxrpc: Fix insufficient receive notification generation
[ Upstream commit f71dbf2fb28489a79bde0dca1c8adfb9cdb20a6b ]

In rxrpc_input_data(), rxrpc_notify_socket() is called if the base sequence
number of the packet is immediately following the hard-ack point at the end
of the function.  However, this isn't sufficient, since the recvmsg side
may have been advancing the window and then overrun the position in which
we're adding - at which point rx_hard_ack >= seq0 and no notification is
generated.

Fix this by always generating a notification at the end of the input
function.

Without this, a long call may stall, possibly indefinitely.

Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:32:07 -05:00
David Howells
37624e6350 rxrpc: Fix uninitialized error code in rxrpc_send_data_packet()
[ Upstream commit 3427beb6375d04e9627c67343872e79341a684ea ]

With gcc 4.1:

    net/rxrpc/output.c: In function ‘rxrpc_send_data_packet’:
    net/rxrpc/output.c:338: warning: ‘ret’ may be used uninitialized in this function

Indeed, if the first jump to the send_fragmentable label is made, and
the address family is not handled in the switch() statement, ret will be
used uninitialized.

Fix this by BUG()'ing as is done in other places in rxrpc where internal
support for future address families will need adding.  It should not be
possible to reach this normally as the address families are checked
up-front.

Fixes: 5a924b8951f835b5 ("rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:46:39 +01:00
David Howells
85aa8f877c rxrpc: Fix possible NULL pointer access in ICMP handling
[ Upstream commit f0308fb0708078d6c1d8a4d533941a7a191af634 ]

If an ICMP packet comes in on the UDP socket backing an AF_RXRPC socket as
the UDP socket is being shut down, rxrpc_error_report() may get called to
deal with it after sk_user_data on the UDP socket has been cleared, leading
to a NULL pointer access when this local endpoint record gets accessed.

Fix this by just returning immediately if sk_user_data was NULL.

The oops looks like the following:

#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
...
RIP: 0010:rxrpc_error_report+0x1bd/0x6a9
...
Call Trace:
 ? sock_queue_err_skb+0xbd/0xde
 ? __udp4_lib_err+0x313/0x34d
 __udp4_lib_err+0x313/0x34d
 icmp_unreach+0x1ee/0x207
 icmp_rcv+0x25b/0x28f
 ip_protocol_deliver_rcu+0x95/0x10e
 ip_local_deliver+0xe9/0x148
 __netif_receive_skb_one_core+0x52/0x6e
 process_backlog+0xdc/0x177
 net_rx_action+0xf9/0x270
 __do_softirq+0x1b6/0x39a
 ? smpboot_register_percpu_thread+0xce/0xce
 run_ksoftirqd+0x1d/0x42
 smpboot_thread_fn+0x19e/0x1b3
 kthread+0xf1/0xf6
 ? kthread_delayed_work_timer_fn+0x83/0x83
 ret_from_fork+0x24/0x30

Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Reported-by: syzbot+611164843bd48cc2190c@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-09 10:17:59 +01:00
David Howells
43159c9ec1 rxrpc: Fix call ref leak
commit c48fc11b69e95007109206311b0187a3090591f3 upstream.

When sendmsg() finds a call to continue on with, if the call is in an
inappropriate state, it doesn't release the ref it just got on that call
before returning an error.

This causes the following symptom to show up with kasan:

	BUG: KASAN: use-after-free in rxrpc_send_keepalive+0x8a2/0x940
	net/rxrpc/output.c:635
	Read of size 8 at addr ffff888064219698 by task kworker/0:3/11077

where line 635 is:

	whdr.epoch	= htonl(peer->local->rxnet->epoch);

The local endpoint (which cannot be pinned by the call) has been released,
but not the peer (which is pinned by the call).

Fix this by releasing the call in the error path.

Fixes: 37411cad633f ("rxrpc: Fix potential NULL-pointer exception")
Reported-by: syzbot+d850c266e3df14da1d31@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-06 12:43:37 +01:00
David Howells
6c8a95ed40 rxrpc: Fix send on a connected, but unbound socket
[ Upstream commit e835ada07091f40dcfb1bc735082bd0a7c005e59 ]

If sendmsg() or sendmmsg() is called on a connected socket that hasn't had
bind() called on it, then an oops will occur when the kernel tries to
connect the call because no local endpoint has been allocated.

Fix this by implicitly binding the socket if it is in the
RXRPC_CLIENT_UNBOUND state, just like it does for the RXRPC_UNBOUND state.

Further, the state should be transitioned to RXRPC_CLIENT_BOUND after this
to prevent further attempts to bind it.

This can be tested with:

	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <sys/socket.h>
	#include <arpa/inet.h>
	#include <linux/rxrpc.h>
	static const unsigned char inet6_addr[16] = {
		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, 0xac, 0x14, 0x14, 0xaa
	};
	int main(void)
	{
		struct sockaddr_rxrpc srx;
		struct cmsghdr *cm;
		struct msghdr msg;
		unsigned char control[16];
		int fd;
		memset(&srx, 0, sizeof(srx));
		srx.srx_family = 0x21;
		srx.srx_service = 0;
		srx.transport_type = AF_INET;
		srx.transport_len = 0x1c;
		srx.transport.sin6.sin6_family = AF_INET6;
		srx.transport.sin6.sin6_port = htons(0x4e22);
		srx.transport.sin6.sin6_flowinfo = htons(0x4e22);
		srx.transport.sin6.sin6_scope_id = htons(0xaa3b);
		memcpy(&srx.transport.sin6.sin6_addr, inet6_addr, 16);
		cm = (struct cmsghdr *)control;
		cm->cmsg_len	= CMSG_LEN(sizeof(unsigned long));
		cm->cmsg_level	= SOL_RXRPC;
		cm->cmsg_type	= RXRPC_USER_CALL_ID;
		*(unsigned long *)CMSG_DATA(cm) = 0;
		msg.msg_name = NULL;
		msg.msg_namelen = 0;
		msg.msg_iov = NULL;
		msg.msg_iovlen = 0;
		msg.msg_control = control;
		msg.msg_controllen = cm->cmsg_len;
		msg.msg_flags = 0;
		fd = socket(AF_RXRPC, SOCK_DGRAM, AF_INET);
		connect(fd, (struct sockaddr *)&srx, sizeof(srx));
		sendmsg(fd, &msg, 0);
		return 0;
	}

Leading to the following oops:

	BUG: kernel NULL pointer dereference, address: 0000000000000018
	#PF: supervisor read access in kernel mode
	#PF: error_code(0x0000) - not-present page
	...
	RIP: 0010:rxrpc_connect_call+0x42/0xa01
	...
	Call Trace:
	 ? mark_held_locks+0x47/0x59
	 ? __local_bh_enable_ip+0xb6/0xba
	 rxrpc_new_client_call+0x3b1/0x762
	 ? rxrpc_do_sendmsg+0x3c0/0x92e
	 rxrpc_do_sendmsg+0x3c0/0x92e
	 rxrpc_sendmsg+0x16b/0x1b5
	 sock_sendmsg+0x2d/0x39
	 ___sys_sendmsg+0x1a4/0x22a
	 ? release_sock+0x19/0x9e
	 ? reacquire_held_locks+0x136/0x160
	 ? release_sock+0x19/0x9e
	 ? find_held_lock+0x2b/0x6e
	 ? __lock_acquire+0x268/0xf73
	 ? rxrpc_connect+0xdd/0xe4
	 ? __local_bh_enable_ip+0xb6/0xba
	 __sys_sendmsg+0x5e/0x94
	 do_syscall_64+0x7d/0x1bf
	 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: 2341e0775747 ("rxrpc: Simplify connect() implementation and simplify sendmsg() op")
Reported-by: syzbot+7966f2a0b2c7da8939b4@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-31 07:28:45 +02:00
David Howells
ccb784fd22 rxrpc: Fix net namespace cleanup
[ Upstream commit b13023421b5179413421333f602850914f6a7ad8 ]

In rxrpc_destroy_all_calls(), there are two phases: (1) make sure the
->calls list is empty, emitting error messages if not, and (2) wait for the
RCU cleanup to happen on outstanding calls (ie. ->nr_calls becomes 0).

To avoid taking the call_lock, the function prechecks ->calls and if empty,
it returns to avoid taking the lock - this is wrong, however: it still
needs to go and do the second phase and wait for ->nr_calls to become 0.

Without this, the rxrpc_net struct may get deallocated before we get to the
RCU cleanup for the last calls.  This can lead to:

  Slab corruption (Not tainted): kmalloc-16k start=ffff88802b178000, len=16384
  050: 6b 6b 6b 6b 6b 6b 6b 6b 61 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkakkkkkkk

Note the "61" at offset 0x58.  This corresponds to the ->nr_calls member of
struct rxrpc_net (which is >9k in size, and thus allocated out of the 16k
slab).

Fix this by flipping the condition on the if-statement, putting the locked
section inside the if-body and dropping the return from there.  The
function will then always go on to wait for the RCU cleanup on outstanding
calls.

Fixes: 2baec2c3f854 ("rxrpc: Support network namespacing")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-08 07:20:44 +02:00
David Howells
a63c7fca08 rxrpc: Fix client call queueing, waiting for channel
[ Upstream commit 69ffaebb90369ce08657b5aea4896777b9d6e8fc ]

rxrpc_get_client_conn() adds a new call to the front of the waiting_calls
queue if the connection it's going to use already exists.  This is bad as
it allows calls to get starved out.

Fix this by adding to the tail instead.

Also change the other enqueue point in the same function to put it on the
front (ie. when we have a new connection).  This makes the point that in
the case of a new connection the new call goes at the front (though it
doesn't actually matter since the queue should be unoccupied).

Fixes: 45025bceef17 ("rxrpc: Improve management and caching of client connection objects")
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19 13:13:23 +01:00
Eric Dumazet
7763f0cce0 rxrpc: bad unlock balance in rxrpc_recvmsg
[ Upstream commit 6dce3c20ac429e7a651d728e375853370c796e8d ]

When either "goto wait_interrupted;" or "goto wait_error;"
paths are taken, socket lock has already been released.

This patch fixes following syzbot splat :

WARNING: bad unlock balance detected!
5.0.0-rc4+ #59 Not tainted
-------------------------------------
syz-executor223/8256 is trying to release lock (sk_lock-AF_RXRPC) at:
[<ffffffff86651353>] rxrpc_recvmsg+0x6d3/0x3099 net/rxrpc/recvmsg.c:598
but there are no more locks to release!

other info that might help us debug this:
1 lock held by syz-executor223/8256:
 #0: 00000000fa9ed0f4 (slock-AF_RXRPC){+...}, at: spin_lock_bh include/linux/spinlock.h:334 [inline]
 #0: 00000000fa9ed0f4 (slock-AF_RXRPC){+...}, at: release_sock+0x20/0x1c0 net/core/sock.c:2798

stack backtrace:
CPU: 1 PID: 8256 Comm: syz-executor223 Not tainted 5.0.0-rc4+ #59
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_unlock_imbalance_bug kernel/locking/lockdep.c:3391 [inline]
 print_unlock_imbalance_bug.cold+0x114/0x123 kernel/locking/lockdep.c:3368
 __lock_release kernel/locking/lockdep.c:3601 [inline]
 lock_release+0x67e/0xa00 kernel/locking/lockdep.c:3860
 sock_release_ownership include/net/sock.h:1471 [inline]
 release_sock+0x183/0x1c0 net/core/sock.c:2808
 rxrpc_recvmsg+0x6d3/0x3099 net/rxrpc/recvmsg.c:598
 sock_recvmsg_nosec net/socket.c:794 [inline]
 sock_recvmsg net/socket.c:801 [inline]
 sock_recvmsg+0xd0/0x110 net/socket.c:797
 __sys_recvfrom+0x1ff/0x350 net/socket.c:1845
 __do_sys_recvfrom net/socket.c:1863 [inline]
 __se_sys_recvfrom net/socket.c:1859 [inline]
 __x64_sys_recvfrom+0xe1/0x1a0 net/socket.c:1859
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446379
Code: e8 2c b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fe5da89fd98 EFLAGS: 00000246 ORIG_RAX: 000000000000002d
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 0000000000446379
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 0000000000000000 R14: 0000000000000000 R15: 20c49ba5e353f7cf

Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Howells <dhowells@redhat.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-12 19:46:10 +01:00
David Howells
252869e5fb rxrpc: Fix connection-level abort handling
[ Upstream commit 647530924f47c93db472ee3cf43b7ef1425581b6 ]

Fix connection-level abort handling to cache the abort and error codes
properly so that a new incoming call can be properly aborted if it races
with the parent connection being aborted by another CPU.

The abort_code and error parameters can then be dropped from
rxrpc_abort_calls().

Fixes: f5c17aaeb2ae ("rxrpc: Calls should only have one terminal state")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-04 14:52:46 +01:00
David Howells
f1d27ff6e0 rxrpc: Only take the rwind and mtu values from latest ACK
[ Upstream commit 298bc15b2079c324e82d0a6fda39c3d762af7282 ]

Move the out-of-order and duplicate ACK packet check to before the call to
rxrpc_input_ackinfo() so that the receive window size and MTU size are only
checked in the latest ACK packet and don't regress.

Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-04 14:52:46 +01:00
David Howells
9a6d45700a rxrpc: Don't check RXRPC_CALL_TX_LAST after calling rxrpc_rotate_tx_window()
[ Upstream commit c479d5f2c2e1ce609da08c075054440d97ddff52 ]

We should only call the function to end a call's Tx phase if we rotated the
marked-last packet out of the transmission buffer.

Make rxrpc_rotate_tx_window() return an indication of whether it just
rotated the packet marked as the last out of the transmit buffer, carrying
the information out of the locked section in that function.

We can then check the return value instead of examining RXRPC_CALL_TX_LAST.

Fixes: 70790dbe3f66 ("rxrpc: Pass the last Tx packet marker in the annotation buffer")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-04 14:52:46 +01:00
YueHaibing
e0638b6a05 rxrpc: Fix user call ID check in rxrpc_service_prealloc_one
[ Upstream commit c01f6c9b3207e52fc9973a066a856ddf7a0538d8 ]

There just check the user call ID isn't already in use, hence should
compare user_call_ID with xcall->user_call_ID, which is current
node's user_call_ID.

Fixes: 540b1c48c37a ("rxrpc: Fix deadlock between call creation and sendmsg/recvmsg")
Suggested-by: David Howells <dhowells@redhat.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-06 16:20:48 +02:00
David Howells
29475c404b rxrpc: Fix the min security level for kernel calls
[ Upstream commit 93864fc3ffcc4bf70e96cfb5cc6e941630419ad0 ]

Fix the kernel call initiation to set the minimum security level for kernel
initiated calls (such as from kAFS) from the sockopt value.

Fixes: 19ffa01c9c45 ("rxrpc: Use structs to hold connection params and protocol info")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-21 04:02:56 +09:00
David Howells
b2abd2b98a rxrpc: Fix error reception on AF_INET6 sockets
[ Upstream commit f2aeed3a591ff29a82495eeaa92ac4780bad7487 ]

AF_RXRPC tries to turn on IP_RECVERR and IP_MTU_DISCOVER on the UDP socket
it just opened for communications with the outside world, regardless of the
type of socket.  Unfortunately, this doesn't work with an AF_INET6 socket.

Fix this by turning on IPV6_RECVERR and IPV6_MTU_DISCOVER instead if the
socket is of the AF_INET6 family.

Without this, kAFS server and address rotation doesn't work correctly
because the algorithm doesn't detect received network errors.

Fixes: 75b54cb57ca3 ("rxrpc: Add IPv6 support")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-21 04:02:56 +09:00
David Howells
637b9b187f rxrpc: Don't treat call aborts as conn aborts
[ Upstream commit 57b0c9d49b94bbeb53649b7fbd264603c1ebd585 ]

If a call-level abort is received for the previous call to complete on a
connection channel, then that abort is queued for the connection processor
to handle.  Unfortunately, the connection processor then assumes without
checking that the abort is connection-level (ie. callNumber is 0) and
distributes it over all active calls on that connection, thereby
incorrectly aborting them.

Fix this by discarding aborts aimed at a completed call.

Further, discard all packets aimed at a call that's complete if there's
currently an active call on a channel, since the DATA packets associated
with the new call automatically terminate the old call.

Fixes: 18bfeba50dfd ("rxrpc: Perform terminal call ACK/ABORT retransmission from conn processor")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:52:26 +02:00
David Howells
4a9fabcd34 rxrpc: Fix Tx ring annotation after initial Tx failure
[ Upstream commit 03877bf6a30cca7d4bc3ffabd3c3e9464a7a1a19 ]

rxrpc calls have a ring of packets that are awaiting ACK or retransmission
and a parallel ring of annotations that tracks the state of those packets.
If the initial transmission of a packet on the underlying UDP socket fails
then the packet annotation is marked for resend - but the setting of this
mark accidentally erases the last-packet mark also stored in the same
annotation slot.  If this happens, a call won't switch out of the Tx phase
when all the packets have been transmitted.

Fix this by retaining the last-packet mark and only altering the packet
state.

Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:52:26 +02:00
David Howells
f146c6e650 rxrpc: Work around usercopy check
[ Upstream commit a16b8d0cf2ec1e626d24bc2a7b9e64ace6f7501d ]

Due to a check recently added to copy_to_user(), it's now not permitted to
copy from slab-held data to userspace unless the slab is whitelisted.  This
affects rxrpc_recvmsg() when it attempts to place an RXRPC_USER_CALL_ID
control message in the userspace control message buffer.  A warning is
generated by usercopy_warn() because the source is the copy of the
user_call_ID retained in the rxrpc_call struct.

Work around the issue by copying the user_call_ID to a variable on the
stack and passing that to put_cmsg().

The warning generated looks like:

	Bad or missing usercopy whitelist? Kernel memory exposure attempt detected from SLUB object 'dmaengine-unmap-128' (offset 680, size 8)!
	WARNING: CPU: 0 PID: 1401 at mm/usercopy.c:81 usercopy_warn+0x7e/0xa0
	...
	RIP: 0010:usercopy_warn+0x7e/0xa0
	...
	Call Trace:
	 __check_object_size+0x9c/0x1a0
	 put_cmsg+0x98/0x120
	 rxrpc_recvmsg+0x6fc/0x1010 [rxrpc]
	 ? finish_wait+0x80/0x80
	 ___sys_recvmsg+0xf8/0x240
	 ? __clear_rsb+0x25/0x3d
	 ? __clear_rsb+0x15/0x3d
	 ? __clear_rsb+0x25/0x3d
	 ? __clear_rsb+0x15/0x3d
	 ? __clear_rsb+0x25/0x3d
	 ? __clear_rsb+0x15/0x3d
	 ? __clear_rsb+0x25/0x3d
	 ? __clear_rsb+0x15/0x3d
	 ? finish_task_switch+0xa6/0x2b0
	 ? trace_hardirqs_on_caller+0xed/0x180
	 ? _raw_spin_unlock_irq+0x29/0x40
	 ? __sys_recvmsg+0x4e/0x90
	 __sys_recvmsg+0x4e/0x90
	 do_syscall_64+0x7a/0x220
	 entry_SYSCALL_64_after_hwframe+0x26/0x9b

Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:51:57 +02:00
David Howells
e781fff7b7 rxrpc: Don't put crypto buffers on the stack
[ Upstream commit 8c2f826dc36314059ac146c78d3bf8056b626446 ]

Don't put buffers of data to be handed to crypto on the stack as this may
cause an assertion failure in the kernel (see below).  Fix this by using an
kmalloc'd buffer instead.

kernel BUG at ./include/linux/scatterlist.h:147!
...
RIP: 0010:rxkad_encrypt_response.isra.6+0x191/0x1b0 [rxrpc]
RSP: 0018:ffffbe2fc06cfca8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff989277d59900 RCX: 0000000000000028
RDX: 0000259dc06cfd88 RSI: 0000000000000025 RDI: ffffbe30406cfd88
RBP: ffffbe2fc06cfd60 R08: ffffbe2fc06cfd08 R09: ffffbe2fc06cfd08
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff7c5f80d9f95
R13: ffffbe2fc06cfd88 R14: ffff98927a3f7aa0 R15: ffffbe2fc06cfd08
FS:  0000000000000000(0000) GS:ffff98927fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b1ff28f0f8 CR3: 000000001b412003 CR4: 00000000003606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 rxkad_respond_to_challenge+0x297/0x330 [rxrpc]
 rxrpc_process_connection+0xd1/0x690 [rxrpc]
 ? process_one_work+0x1c3/0x680
 ? __lock_is_held+0x59/0xa0
 process_one_work+0x249/0x680
 worker_thread+0x3a/0x390
 ? process_one_work+0x680/0x680
 kthread+0x121/0x140
 ? kthread_create_worker_on_cpu+0x70/0x70
 ret_from_fork+0x3a/0x50

Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Jonathan Billings <jsbillings@jsbillings.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-26 11:02:19 +02:00
David Howells
f0a04a0e1a rxrpc: Fix send in rxrpc_send_data_packet()
[ Upstream commit 93c62c45ed5fad1b87e3a45835b251cd68de9c46 ]

All the kernel_sendmsg() calls in rxrpc_send_data_packet() need to send
both parts of the iov[] buffer, but one of them does not.  Fix it so that
it does.

Without this, short IPv6 rxrpc DATA packets may be seen that have the rxrpc
header included, but no payload.

Fixes: 5a924b8951f8 ("rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-08 22:41:12 -08:00
David Howells
1392633baf rxrpc: Fix service endpoint expiry
[ Upstream commit f859ab61875978eeaa539740ff7f7d91f5d60006 ]

RxRPC service endpoints expire like they're supposed to by the following
means:

 (1) Mark dead rxrpc_net structs (with ->live) rather than twiddling the
     global service conn timeout, otherwise the first rxrpc_net struct to
     die will cause connections on all others to expire immediately from
     then on.

 (2) Mark local service endpoints for which the socket has been closed
     (->service_closed) so that the expiration timeout can be much
     shortened for service and client connections going through that
     endpoint.

 (3) rxrpc_put_service_conn() needs to schedule the reaper when the usage
     count reaches 1, not 0, as idle conns have a 1 count.

 (4) The accumulator for the earliest time we might want to schedule for
     should be initialised to jiffies + MAX_JIFFY_OFFSET, not ULONG_MAX as
     the comparison functions use signed arithmetic.

 (5) Simplify the expiration handling, adding the expiration value to the
     idle timestamp each time rather than keeping track of the time in the
     past before which the idle timestamp must go to be expired.  This is
     much easier to read.

 (6) Ignore the timeouts if the net namespace is dead.

 (7) Restart the service reaper work item rather the client reaper.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-03 17:39:01 +01:00
David Howells
b89372f234 rxrpc: Provide a different lockdep key for call->user_mutex for kernel calls
[ Upstream commit 9faaff593404a9c4e5abc6839a641635d7b9d0cd ]

Provide a different lockdep key for rxrpc_call::user_mutex when the call is
made on a kernel socket, such as by the AFS filesystem.

The problem is that lockdep registers a false positive between userspace
calling the sendmsg syscall on a user socket where call->user_mutex is held
whilst userspace memory is accessed whereas the AFS filesystem may perform
operations with mmap_sem held by the caller.

In such a case, the following warning is produced.

======================================================
WARNING: possible circular locking dependency detected
4.14.0-fscache+ #243 Tainted: G            E
------------------------------------------------------
modpost/16701 is trying to acquire lock:
 (&vnode->io_lock){+.+.}, at: [<ffffffffa000fc40>] afs_begin_vnode_operation+0x33/0x77 [kafs]

but task is already holding lock:
 (&mm->mmap_sem){++++}, at: [<ffffffff8104376a>] __do_page_fault+0x1ef/0x486

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #3 (&mm->mmap_sem){++++}:
       __might_fault+0x61/0x89
       _copy_from_iter_full+0x40/0x1fa
       rxrpc_send_data+0x8dc/0xff3
       rxrpc_do_sendmsg+0x62f/0x6a1
       rxrpc_sendmsg+0x166/0x1b7
       sock_sendmsg+0x2d/0x39
       ___sys_sendmsg+0x1ad/0x22b
       __sys_sendmsg+0x41/0x62
       do_syscall_64+0x89/0x1be
       return_from_SYSCALL_64+0x0/0x75

-> #2 (&call->user_mutex){+.+.}:
       __mutex_lock+0x86/0x7d2
       rxrpc_new_client_call+0x378/0x80e
       rxrpc_kernel_begin_call+0xf3/0x154
       afs_make_call+0x195/0x454 [kafs]
       afs_vl_get_capabilities+0x193/0x198 [kafs]
       afs_vl_lookup_vldb+0x5f/0x151 [kafs]
       afs_create_volume+0x2e/0x2f4 [kafs]
       afs_mount+0x56a/0x8d7 [kafs]
       mount_fs+0x6a/0x109
       vfs_kern_mount+0x67/0x135
       do_mount+0x90b/0xb57
       SyS_mount+0x72/0x98
       do_syscall_64+0x89/0x1be
       return_from_SYSCALL_64+0x0/0x75

-> #1 (k-sk_lock-AF_RXRPC){+.+.}:
       lock_sock_nested+0x74/0x8a
       rxrpc_kernel_begin_call+0x8a/0x154
       afs_make_call+0x195/0x454 [kafs]
       afs_fs_get_capabilities+0x17a/0x17f [kafs]
       afs_probe_fileserver+0xf7/0x2f0 [kafs]
       afs_select_fileserver+0x83f/0x903 [kafs]
       afs_fetch_status+0x89/0x11d [kafs]
       afs_iget+0x16f/0x4f8 [kafs]
       afs_mount+0x6c6/0x8d7 [kafs]
       mount_fs+0x6a/0x109
       vfs_kern_mount+0x67/0x135
       do_mount+0x90b/0xb57
       SyS_mount+0x72/0x98
       do_syscall_64+0x89/0x1be
       return_from_SYSCALL_64+0x0/0x75

-> #0 (&vnode->io_lock){+.+.}:
       lock_acquire+0x174/0x19f
       __mutex_lock+0x86/0x7d2
       afs_begin_vnode_operation+0x33/0x77 [kafs]
       afs_fetch_data+0x80/0x12a [kafs]
       afs_readpages+0x314/0x405 [kafs]
       __do_page_cache_readahead+0x203/0x2ba
       filemap_fault+0x179/0x54d
       __do_fault+0x17/0x60
       __handle_mm_fault+0x6d7/0x95c
       handle_mm_fault+0x24e/0x2a3
       __do_page_fault+0x301/0x486
       do_page_fault+0x236/0x259
       page_fault+0x22/0x30
       __clear_user+0x3d/0x60
       padzero+0x1c/0x2b
       load_elf_binary+0x785/0xdc7
       search_binary_handler+0x81/0x1ff
       do_execveat_common.isra.14+0x600/0x888
       do_execve+0x1f/0x21
       SyS_execve+0x28/0x2f
       do_syscall_64+0x89/0x1be
       return_from_SYSCALL_64+0x0/0x75

other info that might help us debug this:

Chain exists of:
  &vnode->io_lock --> &call->user_mutex --> &mm->mmap_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&mm->mmap_sem);
                               lock(&call->user_mutex);
                               lock(&mm->mmap_sem);
  lock(&vnode->io_lock);

 *** DEADLOCK ***

1 lock held by modpost/16701:
 #0:  (&mm->mmap_sem){++++}, at: [<ffffffff8104376a>] __do_page_fault+0x1ef/0x486

stack backtrace:
CPU: 0 PID: 16701 Comm: modpost Tainted: G            E   4.14.0-fscache+ #243
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
Call Trace:
 dump_stack+0x67/0x8e
 print_circular_bug+0x341/0x34f
 check_prev_add+0x11f/0x5d4
 ? add_lock_to_list.isra.12+0x8b/0x8b
 ? add_lock_to_list.isra.12+0x8b/0x8b
 ? __lock_acquire+0xf77/0x10b4
 __lock_acquire+0xf77/0x10b4
 lock_acquire+0x174/0x19f
 ? afs_begin_vnode_operation+0x33/0x77 [kafs]
 __mutex_lock+0x86/0x7d2
 ? afs_begin_vnode_operation+0x33/0x77 [kafs]
 ? afs_begin_vnode_operation+0x33/0x77 [kafs]
 ? afs_begin_vnode_operation+0x33/0x77 [kafs]
 afs_begin_vnode_operation+0x33/0x77 [kafs]
 afs_fetch_data+0x80/0x12a [kafs]
 afs_readpages+0x314/0x405 [kafs]
 __do_page_cache_readahead+0x203/0x2ba
 ? filemap_fault+0x179/0x54d
 filemap_fault+0x179/0x54d
 __do_fault+0x17/0x60
 __handle_mm_fault+0x6d7/0x95c
 handle_mm_fault+0x24e/0x2a3
 __do_page_fault+0x301/0x486
 do_page_fault+0x236/0x259
 page_fault+0x22/0x30
RIP: 0010:__clear_user+0x3d/0x60
RSP: 0018:ffff880071e93da0 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 000000000000011c RCX: 000000000000011c
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 000000000060f720
RBP: 000000000060f720 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffff8800b5459b68 R12: ffff8800ce150e00
R13: 000000000060f720 R14: 00000000006127a8 R15: 0000000000000000
 padzero+0x1c/0x2b
 load_elf_binary+0x785/0xdc7
 search_binary_handler+0x81/0x1ff
 do_execveat_common.isra.14+0x600/0x888
 do_execve+0x1f/0x21
 SyS_execve+0x28/0x2f
 do_syscall_64+0x89/0x1be
 entry_SYSCALL64_slow_path+0x25/0x25
RIP: 0033:0x7fdb6009ee07
RSP: 002b:00007fff566d9728 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 000055ba57280900 RCX: 00007fdb6009ee07
RDX: 000055ba5727f270 RSI: 000055ba5727cac0 RDI: 000055ba57280900
RBP: 000055ba57280900 R08: 00007fff566d9700 R09: 0000000000000000
R10: 000055ba5727cac0 R11: 0000000000000246 R12: 0000000000000000
R13: 000055ba5727cac0 R14: 000055ba5727f270 R15: 0000000000000000

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-03 17:39:01 +01:00
David Howells
92c131bebf rxrpc: The mutex lock returned by rxrpc_accept_call() needs releasing
[ Upstream commit 03a6c82218b9a87014b2c6c4e178294fdc8ebd8a ]

The caller of rxrpc_accept_call() must release the lock on call->user_mutex
returned by that function.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-03 17:39:00 +01:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
David Howells
6cb3ece968 rxrpc: Don't release call mutex on error pointer
Don't release call mutex at the end of rxrpc_kernel_begin_call() if the
call pointer actually holds an error value.

Fixes: 540b1c48c37a ("rxrpc: Fix deadlock between call creation and sendmsg/recvmsg")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-22 03:05:39 +01:00
David Howells
fdade4f69e rxrpc: Make service connection lookup always check for retry
When an RxRPC service packet comes in, the target connection is looked up
by an rb-tree search under RCU and a read-locked seqlock; the seqlock retry
check is, however, currently skipped if we got a match, but probably
shouldn't be in case the connection we found gets replaced whilst we're
doing a search.

Make the lookup procedure always go through need_seqretry(), even if the
lookup was successful.  This makes sure we always pick up on a write-lock
event.

On the other hand, since we don't take a ref on the object, but rely on RCU
to prevent its destruction after dropping the seqlock, I'm not sure this is
necessary.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-05 14:39:17 -07:00
David Howells
c038a58ccf rxrpc: Allow failed client calls to be retried
Allow a client call that failed on network error to be retried, provided
that the Tx queue still holds DATA packet 1.  This allows an operation to
be submitted to another server or another address for the same server
without having to repackage and re-encrypt the data so far processed.

Two new functions are provided:

 (1) rxrpc_kernel_check_call() - This is used to find out the completion
     state of a call to guess whether it can be retried and whether it
     should be retried.

 (2) rxrpc_kernel_retry_call() - Disconnect the call from its current
     connection, reset the state and submit it as a new client call to a
     new address.  The new address need not match the previous address.

A call may be retried even if all the data hasn't been loaded into it yet;
a partially constructed will be retained at the same point it was at when
an error condition was detected.  msg_data_left() can be used to find out
how much data was packaged before the error occurred.

Signed-off-by: David Howells <dhowells@redhat.com>
2017-08-29 10:55:20 +01:00
David Howells
e833251ad8 rxrpc: Add notification of end-of-Tx phase
Add a callback to rxrpc_kernel_send_data() so that a kernel service can get
a notification that the AF_RXRPC call has transitioned out the Tx phase and
is now waiting for a reply or a final ACK.

This is called from AF_RXRPC with the call state lock held so the
notification is guaranteed to come before any reply is passed back.

Further, modify the AFS filesystem to make use of this so that we don't have
to change the afs_call state before sending the last bit of data.

Signed-off-by: David Howells <dhowells@redhat.com>
2017-08-29 10:55:20 +01:00
David Howells
3ec0efde58 rxrpc: Remove some excess whitespace
Remove indentation from some blank lines.

Signed-off-by: David Howells <dhowells@redhat.com>
2017-08-29 10:55:20 +01:00
David Howells
bd2db2d231 rxrpc: Don't negate call->error before returning it
call->error is stored as 0 or a negative error code.  Don't negate this
value (ie. make it positive) before returning it from a kernel function
(though it should still be negated before passing to userspace through a
control message).

Signed-off-by: David Howells <dhowells@redhat.com>
2017-08-29 10:55:20 +01:00
David Howells
7b674e390e rxrpc: Fix IPv6 support
Fix IPv6 support in AF_RXRPC in the following ways:

 (1) When extracting the address from a received IPv4 packet, if the local
     transport socket is open for IPv6 then fill out the sockaddr_rxrpc
     struct for an IPv4-mapped-to-IPv6 AF_INET6 transport address instead
     of an AF_INET one.

 (2) When sending CHALLENGE or RESPONSE packets, the transport length needs
     to be set from the sockaddr_rxrpc::transport_len field rather than
     sizeof() on the IPv4 transport address.

 (3) When processing an IPv4 ICMP packet received by an IPv6 socket, set up
     the address correctly before searching for the affected peer.

Signed-off-by: David Howells <dhowells@redhat.com>
2017-08-29 10:55:20 +01:00
David Howells
0a3785855e rxrpc: Use correct timestamp from Kerberos 5 ticket
When an XDR-encoded Kerberos 5 ticket is added as an rxrpc-type key, the
expiry time should be drawn from the k5 part of the token union (which was
what was filled in), rather than the kad part of the union.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-08-29 10:55:06 +01:00
Baolin Wang
10674a03c6 net: rxrpc: Replace time_t type with time64_t type
Since the 'expiry' variable of 'struct key_preparsed_payload' has been
changed to 'time64_t' type, which is year 2038 safe on 32bits system.

In net/rxrpc subsystem, we need convert 'u32' type to 'time64_t' type
when copying ticket expires time to 'prep->expiry', then this patch
introduces two helper functions to help convert 'u32' to 'time64_t'
type.

This patch also uses ktime_get_real_seconds() to get current time instead
of get_seconds() which is not year 2038 safe on 32bits system.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-08-29 10:16:00 +01:00
David S. Miller
e2a7c34fb2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-08-21 17:06:42 -07:00
David Howells
9a19bad70c rxrpc: Fix oops when discarding a preallocated service call
rxrpc_service_prealloc_one() doesn't set the socket pointer on any new call
it preallocates, but does add it to the rxrpc net namespace call list.
This, however, causes rxrpc_put_call() to oops when the call is discarded
when the socket is closed.  rxrpc_put_call() needs the socket to be able to
reach the namespace so that it can use a lock held therein.

Fix this by setting a call's socket pointer immediately before discarding
it.

This can be triggered by unloading the kafs module, resulting in an oops
like the following:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
IP: rxrpc_put_call+0x1e2/0x32d
PGD 0
P4D 0
Oops: 0000 [#1] SMP
Modules linked in: kafs(E-)
CPU: 3 PID: 3037 Comm: rmmod Tainted: G            E   4.12.0-fscache+ #213
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
task: ffff8803fc92e2c0 task.stack: ffff8803fef74000
RIP: 0010:rxrpc_put_call+0x1e2/0x32d
RSP: 0018:ffff8803fef77e08 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff8803fab99ac0 RCX: 000000000000000f
RDX: ffffffff81c50a40 RSI: 000000000000000c RDI: ffff8803fc92ea88
RBP: ffff8803fef77e30 R08: ffff8803fc87b941 R09: ffffffff82946d20
R10: ffff8803fef77d10 R11: 00000000000076fc R12: 0000000000000005
R13: ffff8803fab99c20 R14: 0000000000000001 R15: ffffffff816c6aee
FS:  00007f915a059700(0000) GS:ffff88041fb80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000030 CR3: 00000003fef39000 CR4: 00000000001406e0
Call Trace:
 rxrpc_discard_prealloc+0x325/0x341
 rxrpc_listen+0xf9/0x146
 kernel_listen+0xb/0xd
 afs_close_socket+0x3e/0x173 [kafs]
 afs_exit+0x1f/0x57 [kafs]
 SyS_delete_module+0x10f/0x19a
 do_syscall_64+0x8a/0x149
 entry_SYSCALL64_slow_path+0x25/0x25

Fixes: 2baec2c3f854 ("rxrpc: Support network namespacing")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-18 16:23:23 -07:00
David Howells
ddc6c70f07 rxrpc: Move the packet.h include file into net/rxrpc/
Move the protocol description header file into net/rxrpc/ and rename it to
protocol.h.  It's no longer necessary to expose it as packets are no longer
exposed to kernel services (such as AFS) that use the facility.

The abort codes are transferred to the UAPI header instead as we pass these
back to userspace and also to kernel services.

Signed-off-by: David Howells <dhowells@redhat.com>
2017-07-21 11:00:20 +01:00
Reshetova, Elena
41c6d650f6 net: convert sock.sk_refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

This patch uses refcount_inc_not_zero() instead of
atomic_inc_not_zero_hint() due to absense of a _hint()
version of refcount API. If the hint() version must
be used, we might need to revisit API.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-01 07:39:08 -07:00
Reshetova, Elena
14afee4b60 net: convert sock.sk_wmem_alloc from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-01 07:39:08 -07:00