Fix rxrpc_new_incoming_call() to check that we have a suitable service key
available for the combination of service ID and security class of a new
incoming call - and to reject calls for which we don't.

This causes an assertion like the following to appear:

	rxrpc: Assertion failed - 6(0x6) == 12(0xc) is false
	kernel BUG at net/rxrpc/call_object.c:456!

Where call->state is RXRPC_CALL_SERVER_SECURING (6) rather than
RXRPC_CALL_COMPLETE (12).

Fixes: 248f219c ("rxrpc: Rewrite the data and ack handling code")
Reported-by: NMarc Dionne <marc.dionne@auristor.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Standard kernel mutexes cannot be used in any way from interrupt or softirq
context, so the user_mutex which manages access to a call cannot be a mutex
since on a new call the mutex must start off locked and be unlocked within
the softirq handler to prevent userspace interfering with a call we're
setting up.

Commit a0855d24 ("locking/mutex: Complain
upon mutex API misuse in IRQ contexts") causes big warnings to be splashed
in dmesg for each a new call that comes in from the server.  Whilst it
*seems* like it should be okay, since the accept path uses trylock, there
are issues with PI boosting and marking the wrong task as the owner.

Fix this by not taking the mutex in the softirq path at all.  It's not
obvious that there should be any need for it as the state is set before the
first notification is generated for the new call.

There's also no particular reason why the link-assessing ping should be
triggered inside the mutex.  It's not actually transmitted there anyway,
but rather it has to be deferred to a workqueue.

Further, I don't think that there's any particular reason that the socket
notification needs to be done from within rx->incoming_lock, so the amount
of time that lock is held can be shortened too and the ping prepared before
the new call notification is sent.

Fixes: 540b1c48 ("rxrpc: Fix deadlock between call creation and sendmsg/recvmsg")
Signed-off-by: NDavid Howells <dhowells@redhat.com>
cc: Peter Zijlstra (Intel) <peterz@infradead.org>
cc: Ingo Molnar <mingo@redhat.com>
cc: Will Deacon <will@kernel.org>
cc: Davidlohr Bueso <dave@stgolabs.net>

Move the unlock and the ping transmission for a new incoming call into
rxrpc_new_incoming_call() rather than doing it in the caller.  This makes
it clearer to see what's going on.
Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
cc: Ingo Molnar <mingo@redhat.com>
cc: Will Deacon <will@kernel.org>
cc: Davidlohr Bueso <dave@stgolabs.net>

Now that the blkcipher algorithm type has been removed in favor of
skcipher, rename the crypto_blkcipher kernel module to crypto_skcipher,
and rename the config options accordingly:

	CONFIG_CRYPTO_BLKCIPHER => CONFIG_CRYPTO_SKCIPHER
	CONFIG_CRYPTO_BLKCIPHER2 => CONFIG_CRYPTO_SKCIPHER2
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

When rxrpc_recvmsg_data() sets the return value to 1 because it's drained
all the data for the last packet, it checks the last-packet flag on the
whole packet - but this is wrong, since the last-packet flag is only set on
the final subpacket of the last jumbo packet.  This means that a call that
receives its last packet in a jumbo packet won't complete properly.

Fix this by having rxrpc_locate_data() determine the last-packet state of
the subpacket it's looking at and passing that back to the caller rather
than having the caller look in the packet header.  The caller then needs to
cache this in the rxrpc_call struct as rxrpc_locate_data() isn't then
called again for this packet.

Fixes: 248f219c ("rxrpc: Rewrite the data and ack handling code")
Fixes: e2de6c40 ("rxrpc: Use info in skbuff instead of reparsing a jumbo packet")
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to extend the rcu_read_lock() section in rxrpc_error_report()
and use rcu_dereference_sk_user_data() instead of plain access
to sk->sk_user_data to make sure all rules are respected.

The compiler wont reload sk->sk_user_data at will, and RCU rules
prevent memory beeing freed too soon.

Fixes: f0308fb0 ("rxrpc: Fix possible NULL pointer access in ICMP handling")
Fixes: 17926a79 ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: 17926a79 ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Reported-by: syzbot+611164843bd48cc2190c@syzkaller.appspotmail.com
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix the cleanup of the crypto state on a call after the call has been
disconnected.  As the call has been disconnected, its connection ref has
been discarded and so we can't go through that to get to the security ops
table.

Fix this by caching the security ops pointer in the rxrpc_call struct and
using that when freeing the call security state.  Also use this in other
places we're dealing with call-specific security.

The symptoms look like:

    BUG: KASAN: use-after-free in rxrpc_release_call+0xb2d/0xb60
    net/rxrpc/call_object.c:481
    Read of size 8 at addr ffff888062ffeb50 by task syz-executor.5/4764

Fixes: 1db88c53 ("rxrpc: Fix -Wframe-larger-than= warnings from on-stack crypto")
Reported-by: syzbot+eed305768ece6682bb7f@syzkaller.appspotmail.com
Signed-off-by: NDavid Howells <dhowells@redhat.com>

The rxrpc_peer record needs to hold a reference on the rxrpc_local record
it points as the peer is used as a base to access information in the
rxrpc_local record.

This can cause problems in __rxrpc_put_peer(), where we need the network
namespace pointer, and in rxrpc_send_keepalive(), where we need to access
the UDP socket, leading to symptoms like:

    BUG: KASAN: use-after-free in __rxrpc_put_peer net/rxrpc/peer_object.c:411
    [inline]
    BUG: KASAN: use-after-free in rxrpc_put_peer+0x685/0x6a0
    net/rxrpc/peer_object.c:435
    Read of size 8 at addr ffff888097ec0058 by task syz-executor823/24216

Fix this by taking a ref on the local record for the peer record.

Fixes: ace45bec ("rxrpc: Fix firewall route keepalive")
Fixes: 2baec2c3 ("rxrpc: Support network namespacing")
Reported-by: syzbot+b9be979c55f2bea8ed30@syzkaller.appspotmail.com
Signed-off-by: NDavid Howells <dhowells@redhat.com>

rxrpc_put_call() calls trace_rxrpc_call() after it has done the decrement
of the refcount - which looks at the debug_id in the call record.  But
unless the refcount was reduced to zero, we no longer have the right to
look in the record and, indeed, it may be deleted by some other thread.

Fix this by getting the debug_id out before decrementing the refcount and
then passing that into the tracepoint.

Fixes: e34d4234 ("rxrpc: Trace rxrpc_call usage")
Signed-off-by: NDavid Howells <dhowells@redhat.com>

rxrpc_put_*conn() calls trace_rxrpc_conn() after they have done the
decrement of the refcount - which looks at the debug_id in the connection
record.  But unless the refcount was reduced to zero, we no longer have the
right to look in the record and, indeed, it may be deleted by some other
thread.

Fix this by getting the debug_id out before decrementing the refcount and
then passing that into the tracepoint.

Fixes: 363deeab ("rxrpc: Add connection tracepoint and client conn state tracepoint")
Signed-off-by: NDavid Howells <dhowells@redhat.com>

rxrpc_put_peer() calls trace_rxrpc_peer() after it has done the decrement
of the refcount - which looks at the debug_id in the peer record.  But
unless the refcount was reduced to zero, we no longer have the right to
look in the record and, indeed, it may be deleted by some other thread.

Fix this by getting the debug_id out before decrementing the refcount and
then passing that into the tracepoint.

This can cause the following symptoms:

    BUG: KASAN: use-after-free in __rxrpc_put_peer net/rxrpc/peer_object.c:411
    [inline]
    BUG: KASAN: use-after-free in rxrpc_put_peer+0x685/0x6a0
    net/rxrpc/peer_object.c:435
    Read of size 8 at addr ffff888097ec0058 by task syz-executor823/24216

Fixes: 1159d4b4 ("rxrpc: Add a tracepoint to track rxrpc_peer refcounting")
Reported-by: syzbot+b9be979c55f2bea8ed30@syzkaller.appspotmail.com
Signed-off-by: NDavid Howells <dhowells@redhat.com>

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: 37411cad ("rxrpc: Fix potential NULL-pointer exception")
Reported-by: syzbot+d850c266e3df14da1d31@syzkaller.appspotmail.com
Signed-off-by: NDavid Howells <dhowells@redhat.com>

There was supposed to be a trace indicating that a new peer had been
created.  Add it.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There's a misplaced traceline in rxrpc_input_packet() which is looking at a
packet that just got released rather than the replacement packet.

Fix this by moving the traceline after the assignment that moves the new
packet pointer to the actual packet pointer.

Fixes: d0d5c0cd ("rxrpc: Use skb_unshare() rather than skb_cow_data()")
Reported-by: NHillf Danton <hdanton@sina.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a local endpoint is ceases to be in use, such as when the kafs module
is unloaded, the kernel will emit an assertion failure if there are any
outstanding client connections:

	rxrpc: Assertion failed
	------------[ cut here ]------------
	kernel BUG at net/rxrpc/local_object.c:433!

and even beyond that, will evince other oopses if there are service
connections still present.

Fix this by:

 (1) Removing the triggering of connection reaping when an rxrpc socket is
     released.  These don't actually clean up the connections anyway - and
     further, the local endpoint may still be in use through another
     socket.

 (2) Mark the local endpoint as dead when we start the process of tearing
     it down.

 (3) When destroying a local endpoint, strip all of its client connections
     from the idle list and discard the ref on each that the list was
     holding.

 (4) When destroying a local endpoint, call the service connection reaper
     directly (rather than through a workqueue) to immediately kill off all
     outstanding service connections.

 (5) Make the service connection reaper reap connections for which the
     local endpoint is marked dead.

Only after destroying the connections can we close the socket lest we get
an oops in a workqueue that's looking at a connection or a peer.

Fixes: 3d18cbb7 ("rxrpc: Fix conn expiry timers")
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Tested-by: NMarc Dionne <marc.dionne@auristor.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The in-place decryption routines in AF_RXRPC's rxkad security module
currently call skb_cow_data() to make sure the data isn't shared and that
the skb can be written over.  This has a problem, however, as the softirq
handler may be still holding a ref or the Rx ring may be holding multiple
refs when skb_cow_data() is called in rxkad_verify_packet() - and so
skb_shared() returns true and __pskb_pull_tail() dislikes that.  If this
occurs, something like the following report will be generated.

	kernel BUG at net/core/skbuff.c:1463!
	...
	RIP: 0010:pskb_expand_head+0x253/0x2b0
	...
	Call Trace:
	 __pskb_pull_tail+0x49/0x460
	 skb_cow_data+0x6f/0x300
	 rxkad_verify_packet+0x18b/0xb10 [rxrpc]
	 rxrpc_recvmsg_data.isra.11+0x4a8/0xa10 [rxrpc]
	 rxrpc_kernel_recv_data+0x126/0x240 [rxrpc]
	 afs_extract_data+0x51/0x2d0 [kafs]
	 afs_deliver_fs_fetch_data+0x188/0x400 [kafs]
	 afs_deliver_to_call+0xac/0x430 [kafs]
	 afs_wait_for_call_to_complete+0x22f/0x3d0 [kafs]
	 afs_make_call+0x282/0x3f0 [kafs]
	 afs_fs_fetch_data+0x164/0x300 [kafs]
	 afs_fetch_data+0x54/0x130 [kafs]
	 afs_readpages+0x20d/0x340 [kafs]
	 read_pages+0x66/0x180
	 __do_page_cache_readahead+0x188/0x1a0
	 ondemand_readahead+0x17d/0x2e0
	 generic_file_read_iter+0x740/0xc10
	 __vfs_read+0x145/0x1a0
	 vfs_read+0x8c/0x140
	 ksys_read+0x4a/0xb0
	 do_syscall_64+0x43/0xf0
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix this by using skb_unshare() instead in the input path for DATA packets
that have a security index != 0.  Non-DATA packets don't need in-place
encryption and neither do unencrypted DATA packets.

Fixes: 248f219c ("rxrpc: Rewrite the data and ack handling code")
Reported-by: NJulian Wollrath <jwollrath@web.de>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Use the previously-added transmit-phase skbuff private flag to simplify the
socket buffer tracing a bit.  Which phase the skbuff comes from can now be
divined from the skb rather than having to be guessed from the call state.

We can also reduce the number of rxrpc_skb_trace values by eliminating the
difference between Tx and Rx in the symbols.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

    
Add a flag in the private data on an skbuff to indicate that this is a
transmission-phase buffer rather than a receive-phase buffer.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Abstract out rxtx ring cleanup into its own function from its two callers.
This makes it easier to apply the same changes to both.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Pass the reference held on a DATA skb in the rxrpc input handler into the
Rx ring rather than getting an additional ref for this and then dropping
the original ref at the end.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Use the information now cached in the skbuff private data to avoid the need
to reparse a jumbo packet.  We can find all the subpackets by dead
reckoning, so it's only necessary to note how many there are, whether the
last one is flagged as LAST_PACKET and whether any have the REQUEST_ACK
flag set.

This is necessary as once recvmsg() can see the packet, it can start
modifying it, such as doing in-place decryption.

Fixes: 248f219c ("rxrpc: Rewrite the data and ack handling code")
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Improve the information stored about jumbo packets so that we don't need to
reparse them so much later.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NJeffrey Altman <jaltman@auristor.com>

rxrpc_queue_local() attempts to queue the local endpoint it is given and
then, if successful, prints a trace line.  The trace line includes the
current usage count - but we're not allowed to look at the local endpoint
at this point as we passed our ref on it to the workqueue.

Fix this by reading the usage count before queuing the work item.

Also fix the reading of local->debug_id for trace lines, which must be done
with the same consideration as reading the usage count.

Fixes: 09d2bf59 ("rxrpc: Add a tracepoint to track rxrpc_local refcounting")
Reported-by: syzbot+78e71c5bab4f76a6a719@syzkaller.appspotmail.com
Signed-off-by: NDavid Howells <dhowells@redhat.com>

When a local endpoint (struct rxrpc_local) ceases to be in use by any
AF_RXRPC sockets, it starts the process of being destroyed, but this
doesn't cause it to be removed from the namespace endpoint list immediately
as tearing it down isn't trivial and can't be done in softirq context, so
it gets deferred.

If a new socket comes along that wants to bind to the same endpoint, a new
rxrpc_local object will be allocated and rxrpc_lookup_local() will use
list_replace() to substitute the new one for the old.

Then, when the dying object gets to rxrpc_local_destroyer(), it is removed
unconditionally from whatever list it is on by calling list_del_init().

However, list_replace() doesn't reset the pointers in the replaced
list_head and so the list_del_init() will likely corrupt the local
endpoints list.

Fix this by using list_replace_init() instead.

Fixes: 730c5fd4 ("rxrpc: Fix local endpoint refcounting")
Reported-by: syzbot+193e29e9387ea5837f1d@syzkaller.appspotmail.com
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Fix rxrpc_unuse_local() to handle a NULL local pointer as it can be called
on an unbound socket on which rx->local is not yet set.

The following reproduced (includes omitted):

	int main(void)
	{
		socket(AF_RXRPC, SOCK_DGRAM, AF_INET);
		return 0;
	}

causes the following oops to occur:

	BUG: kernel NULL pointer dereference, address: 0000000000000010
	...
	RIP: 0010:rxrpc_unuse_local+0x8/0x1b
	...
	Call Trace:
	 rxrpc_release+0x2b5/0x338
	 __sock_release+0x37/0xa1
	 sock_close+0x14/0x17
	 __fput+0x115/0x1e9
	 task_work_run+0x72/0x98
	 do_exit+0x51b/0xa7a
	 ? __context_tracking_exit+0x4e/0x10e
	 do_group_exit+0xab/0xab
	 __x64_sys_exit_group+0x14/0x17
	 do_syscall_64+0x89/0x1d4
	 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Reported-by: syzbot+20dee719a2e090427b5f@syzkaller.appspotmail.com
Fixes: 730c5fd4 ("rxrpc: Fix local endpoint refcounting")
Signed-off-by: NDavid Howells <dhowells@redhat.com>
cc: Jeffrey Altman <jaltman@auristor.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't bother generating maxSkew in the ACK packet as it has been obsolete
since AFS 3.1.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NJeffrey Altman <jaltman@auristor.com>

The object lifetime management on the rxrpc_local struct is broken in that
the rxrpc_local_processor() function is expected to clean up and remove an
object - but it may get requeued by packets coming in on the backing UDP
socket once it starts running.

This may result in the assertion in rxrpc_local_rcu() firing because the
memory has been scheduled for RCU destruction whilst still queued:

	rxrpc: Assertion failed
	------------[ cut here ]------------
	kernel BUG at net/rxrpc/local_object.c:468!

Note that if the processor comes around before the RCU free function, it
will just do nothing because ->dead is true.

Fix this by adding a separate refcount to count active users of the
endpoint that causes the endpoint to be destroyed when it reaches 0.

The original refcount can then be used to refcount objects through the work
processor and cause the memory to be rcu freed when that reaches 0.

Fixes: 4f95dd78 ("rxrpc: Rework local endpoint management")
Reported-by: syzbot+1e0edc4b8b7494c28450@syzkaller.appspotmail.com
Signed-off-by: NDavid Howells <dhowells@redhat.com>

rxkad sometimes triggers a warning about oversized stack frames when
building with clang for a 32-bit architecture:

net/rxrpc/rxkad.c:243:12: error: stack frame size of 1088 bytes in function 'rxkad_secure_packet' [-Werror,-Wframe-larger-than=]
net/rxrpc/rxkad.c:501:12: error: stack frame size of 1088 bytes in function 'rxkad_verify_packet' [-Werror,-Wframe-larger-than=]

The problem is the combination of SYNC_SKCIPHER_REQUEST_ON_STACK() in
rxkad_verify_packet()/rxkad_secure_packet() with the relatively large
scatterlist in rxkad_verify_packet_1()/rxkad_secure_packet_encrypt().

The warning does not show up when using gcc, which does not inline the
functions as aggressively, but the problem is still the same.

Allocate the cipher buffers from the slab instead, caching the allocated
packet crypto request memory used for DATA packet crypto in the rxrpc_call
struct.

Fixes: 17926a79 ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Reported-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix the fact that a notification isn't sent to the recvmsg side to indicate
a call failed when sendmsg() fails to transmit a DATA packet with the error
ENETUNREACH, EHOSTUNREACH or ECONNREFUSED.

Without this notification, the afs client just sits there waiting for the
call to complete in some manner (which it's not now going to do), which
also pins the rxrpc call in place.

This can be seen if the client has a scope-level IPv6 address, but not a
global-level IPv6 address, and we try and transmit an operation to a
server's IPv6 address.

Looking in /proc/net/rxrpc/calls shows completed calls just sat there with
an abort code of RX_USER_ABORT and an error code of -ENETUNREACH.

Fixes: c54e43d7 ("rxrpc: Fix missing start of call timeout")
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NMarc Dionne <marc.dionne@auristor.com>
Reviewed-by: NJeffrey Altman <jaltman@auristor.com>

There is a potential deadlock in rxrpc_peer_keepalive_dispatch() whereby
rxrpc_put_peer() is called with the peer_hash_lock held, but if it reduces
the peer's refcount to 0, rxrpc_put_peer() calls __rxrpc_put_peer() - which
the tries to take the already held lock.

Fix this by providing a version of rxrpc_put_peer() that can be called in
situations where the lock is already held.

The bug may produce the following lockdep report:

============================================
WARNING: possible recursive locking detected
5.2.0-next-20190718 #41 Not tainted
--------------------------------------------
kworker/0:3/21678 is trying to acquire lock:
00000000aa5eecdf (&(&rxnet->peer_hash_lock)->rlock){+.-.}, at: spin_lock_bh
/./include/linux/spinlock.h:343 [inline]
00000000aa5eecdf (&(&rxnet->peer_hash_lock)->rlock){+.-.}, at:
__rxrpc_put_peer /net/rxrpc/peer_object.c:415 [inline]
00000000aa5eecdf (&(&rxnet->peer_hash_lock)->rlock){+.-.}, at:
rxrpc_put_peer+0x2d3/0x6a0 /net/rxrpc/peer_object.c:435

but task is already holding lock:
00000000aa5eecdf (&(&rxnet->peer_hash_lock)->rlock){+.-.}, at: spin_lock_bh
/./include/linux/spinlock.h:343 [inline]
00000000aa5eecdf (&(&rxnet->peer_hash_lock)->rlock){+.-.}, at:
rxrpc_peer_keepalive_dispatch /net/rxrpc/peer_event.c:378 [inline]
00000000aa5eecdf (&(&rxnet->peer_hash_lock)->rlock){+.-.}, at:
rxrpc_peer_keepalive_worker+0x6b3/0xd02 /net/rxrpc/peer_event.c:430

Fixes: 330bdcfa ("rxrpc: Fix the keepalive generator [ver #2]")
Reported-by: syzbot+72af434e4b3417318f84@syzkaller.appspotmail.com
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NMarc Dionne <marc.dionne@auristor.com>
Reviewed-by: NJeffrey Altman <jaltman@auristor.com>

In the sysctl code the proc_dointvec_minmax() function is often used to
validate the user supplied value between an allowed range.  This
function uses the extra1 and extra2 members from struct ctl_table as
minimum and maximum allowed value.

On sysctl handler declaration, in every source file there are some
readonly variables containing just an integer which address is assigned
to the extra1 and extra2 members, so the sysctl range is enforced.

The special values 0, 1 and INT_MAX are very often used as range
boundary, leading duplication of variables like zero=0, one=1,
int_max=INT_MAX in different source files:

    $ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l
    248

Add a const int array containing the most commonly used values, some
macros to refer more easily to the correct array member, and use them
instead of creating a local one for every object file.

This is the bloat-o-meter output comparing the old and new binary
compiled with the default Fedora config:

    # scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o
    add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164)
    Data                                         old     new   delta
    sysctl_vals                                    -      12     +12
    __kstrtab_sysctl_vals                          -      12     +12
    max                                           14      10      -4
    int_max                                       16       -     -16
    one                                           68       -     -68
    zero                                         128      28    -100
    Total: Before=20583249, After=20583085, chg -0.00%

[mcroce@redhat.com: tipc: remove two unused variables]
  Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com
[akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c]
[arnd@arndb.de: proc/sysctl: make firmware loader table conditional]
  Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de
[akpm@linux-foundation.org: fix fs/eventpoll.c]
Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.comSigned-off-by: NMatteo Croce <mcroce@redhat.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NAaron Tomlin <atomlin@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs"

This reverts merge 0f75ef6a (and thus
effectively commits

   7a1ade84 ("keys: Provide KEYCTL_GRANT_PERMISSION")
   2e12256b ("keys: Replace uid/gid/perm permissions checking with an ACL")

that the merge brought in).

It turns out that it breaks booting with an encrypted volume, and Eric
biggers reports that it also breaks the fscrypt tests [1] and loading of
in-kernel X.509 certificates [2].

The root cause of all the breakage is likely the same, but David Howells
is off email so rather than try to work it out it's getting reverted in
order to not impact the rest of the merge window.

 [1] https://lore.kernel.org/lkml/20190710011559.GA7973@sol.localdomain/
 [2] https://lore.kernel.org/lkml/20190710013225.GB7973@sol.localdomain/

Link: https://lore.kernel.org/lkml/CAHk-=wjxoeMJfeBahnWH=9zShKp2bsVy527vo3_y8HfOdhwAAw@mail.gmail.com/Reported-by: NEric Biggers <ebiggers@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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: 2341e077 ("rxrpc: Simplify connect() implementation and simplify sendmsg() op")
Reported-by: syzbot+7966f2a0b2c7da8939b4@syzkaller.appspotmail.com
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NMarc Dionne <marc.dionne@auristor.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: 5a924b89 ("rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs")
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Replace the uid/gid/perm permissions checking on a key with an ACL to allow
the SETATTR and SEARCH permissions to be split.  This will also allow a
greater range of subjects to represented.

============
WHY DO THIS?
============

The problem is that SETATTR and SEARCH cover a slew of actions, not all of
which should be grouped together.

For SETATTR, this includes actions that are about controlling access to a
key:

 (1) Changing a key's ownership.

 (2) Changing a key's security information.

 (3) Setting a keyring's restriction.

And actions that are about managing a key's lifetime:

 (4) Setting an expiry time.

 (5) Revoking a key.

and (proposed) managing a key as part of a cache:

 (6) Invalidating a key.

Managing a key's lifetime doesn't really have anything to do with
controlling access to that key.

Expiry time is awkward since it's more about the lifetime of the content
and so, in some ways goes better with WRITE permission.  It can, however,
be set unconditionally by a process with an appropriate authorisation token
for instantiating a key, and can also be set by the key type driver when a
key is instantiated, so lumping it with the access-controlling actions is
probably okay.

As for SEARCH permission, that currently covers:

 (1) Finding keys in a keyring tree during a search.

 (2) Permitting keyrings to be joined.

 (3) Invalidation.

But these don't really belong together either, since these actions really
need to be controlled separately.

Finally, there are number of special cases to do with granting the
administrator special rights to invalidate or clear keys that I would like
to handle with the ACL rather than key flags and special checks.


===============
WHAT IS CHANGED
===============

The SETATTR permission is split to create two new permissions:

 (1) SET_SECURITY - which allows the key's owner, group and ACL to be
     changed and a restriction to be placed on a keyring.

 (2) REVOKE - which allows a key to be revoked.

The SEARCH permission is split to create:

 (1) SEARCH - which allows a keyring to be search and a key to be found.

 (2) JOIN - which allows a keyring to be joined as a session keyring.

 (3) INVAL - which allows a key to be invalidated.

The WRITE permission is also split to create:

 (1) WRITE - which allows a key's content to be altered and links to be
     added, removed and replaced in a keyring.

 (2) CLEAR - which allows a keyring to be cleared completely.  This is
     split out to make it possible to give just this to an administrator.

 (3) REVOKE - see above.


Keys acquire ACLs which consist of a series of ACEs, and all that apply are
unioned together.  An ACE specifies a subject, such as:

 (*) Possessor - permitted to anyone who 'possesses' a key
 (*) Owner - permitted to the key owner
 (*) Group - permitted to the key group
 (*) Everyone - permitted to everyone

Note that 'Other' has been replaced with 'Everyone' on the assumption that
you wouldn't grant a permit to 'Other' that you wouldn't also grant to
everyone else.

Further subjects may be made available by later patches.

The ACE also specifies a permissions mask.  The set of permissions is now:

	VIEW		Can view the key metadata
	READ		Can read the key content
	WRITE		Can update/modify the key content
	SEARCH		Can find the key by searching/requesting
	LINK		Can make a link to the key
	SET_SECURITY	Can change owner, ACL, expiry
	INVAL		Can invalidate
	REVOKE		Can revoke
	JOIN		Can join this keyring
	CLEAR		Can clear this keyring


The KEYCTL_SETPERM function is then deprecated.

The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set,
or if the caller has a valid instantiation auth token.

The KEYCTL_INVALIDATE function then requires INVAL.

The KEYCTL_REVOKE function then requires REVOKE.

The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an
existing keyring.

The JOIN permission is enabled by default for session keyrings and manually
created keyrings only.


======================
BACKWARD COMPATIBILITY
======================

To maintain backward compatibility, KEYCTL_SETPERM will translate the
permissions mask it is given into a new ACL for a key - unless
KEYCTL_SET_ACL has been called on that key, in which case an error will be
returned.

It will convert possessor, owner, group and other permissions into separate
ACEs, if each portion of the mask is non-zero.

SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY.  WRITE
permission turns on WRITE, REVOKE and, if a keyring, CLEAR.  JOIN is turned
on if a keyring is being altered.

The KEYCTL_DESCRIBE function translates the ACL back into a permissions
mask to return depending on possessor, owner, group and everyone ACEs.

It will make the following mappings:

 (1) INVAL, JOIN -> SEARCH

 (2) SET_SECURITY -> SETATTR

 (3) REVOKE -> WRITE if SETATTR isn't already set

 (4) CLEAR -> WRITE

Note that the value subsequently returned by KEYCTL_DESCRIBE may not match
the value set with KEYCTL_SETATTR.


=======
TESTING
=======

This passes the keyutils testsuite for all but a couple of tests:

 (1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now
     returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed
     if the type doesn't have ->read().  You still can't actually read the
     key.

 (2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't
     work as Other has been replaced with Everyone in the ACL.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Create a request_key_net() function and use it to pass the network
namespace domain tag into DNS revolver keys and rxrpc/AFS keys so that keys
for different domains can coexist in the same keyring.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
cc: netdev@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-afs@lists.infradead.org

Create key domain tags for network namespaces and make it possible to
automatically tag keys that are used by networked services (e.g. AF_RXRPC,
AFS, DNS) with the default network namespace if not set by the caller.

This allows keys with the same description but in different namespaces to
coexist within a keyring.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
cc: netdev@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-afs@lists.infradead.org

Add a 'recurse' flag for keyring searches so that the flag can be omitted
and recursion disabled, thereby allowing just the nominated keyring to be
searched and none of the children.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NAllison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.deSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>