Commit Graph

28 Commits

Author SHA1 Message Date
David Howells 554e23bf69 rxrpc: Fix clearance of Tx/Rx ring when releasing a call
commit 7b5eab57cac45e270a0ad624ba157c5b30b3d44d upstream.

At the end of rxrpc_release_call(), rxrpc_cleanup_ring() is called to clear
the Rx/Tx skbuff ring, but this doesn't lock the ring whilst it's accessing
it.  Unfortunately, rxrpc_resend() might be trying to retransmit a packet
concurrently with this - and whilst it does lock the ring, this isn't
protection against rxrpc_cleanup_call().

Fix this by removing the call to rxrpc_cleanup_ring() from
rxrpc_release_call().  rxrpc_cleanup_ring() will be called again anyway
from rxrpc_cleanup_call().  The earlier call is just an optimisation to
recycle skbuffs more quickly.

Alternative solutions include rxrpc_release_call() could try to cancel the
work item or wait for it to complete or rxrpc_cleanup_ring() could lock
when accessing the ring (which would require a bh lock).

This can produce a report like the following:

  BUG: KASAN: use-after-free in rxrpc_send_data_packet+0x19b4/0x1e70 net/rxrpc/output.c:372
  Read of size 4 at addr ffff888011606e04 by task kworker/0:0/5
  ...
  Workqueue: krxrpcd rxrpc_process_call
  Call Trace:
   ...
   kasan_report.cold+0x79/0xd5 mm/kasan/report.c:413
   rxrpc_send_data_packet+0x19b4/0x1e70 net/rxrpc/output.c:372
   rxrpc_resend net/rxrpc/call_event.c:266 [inline]
   rxrpc_process_call+0x1634/0x1f60 net/rxrpc/call_event.c:412
   process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275
   ...

  Allocated by task 2318:
   ...
   sock_alloc_send_pskb+0x793/0x920 net/core/sock.c:2348
   rxrpc_send_data+0xb51/0x2bf0 net/rxrpc/sendmsg.c:358
   rxrpc_do_sendmsg+0xc03/0x1350 net/rxrpc/sendmsg.c:744
   rxrpc_sendmsg+0x420/0x630 net/rxrpc/af_rxrpc.c:560
   ...

  Freed by task 2318:
   ...
   kfree_skb+0x140/0x3f0 net/core/skbuff.c:704
   rxrpc_free_skb+0x11d/0x150 net/rxrpc/skbuff.c:78
   rxrpc_cleanup_ring net/rxrpc/call_object.c:485 [inline]
   rxrpc_release_call+0x5dd/0x860 net/rxrpc/call_object.c:552
   rxrpc_release_calls_on_socket+0x21c/0x300 net/rxrpc/call_object.c:579
   rxrpc_release_sock net/rxrpc/af_rxrpc.c:885 [inline]
   rxrpc_release+0x263/0x5a0 net/rxrpc/af_rxrpc.c:916
   __sock_release+0xcd/0x280 net/socket.c:597
   ...

  The buggy address belongs to the object at ffff888011606dc0
   which belongs to the cache skbuff_head_cache of size 232

Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
Reported-by: syzbot+174de899852504e4a74a@syzkaller.appspotmail.com
Reported-by: syzbot+3d1c772efafd3c38d007@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/161234207610.653119.5287360098400436976.stgit@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:52:05 +08:00
David Howells b611f66ccf rxrpc: Fix deadlock around release of dst cached on udp tunnel
[ Upstream commit 5399d52233c47905bbf97dcbaa2d7a9cc31670ba ]

AF_RXRPC sockets use UDP ports in encap mode.  This causes socket and dst
from an incoming packet to get stolen and attached to the UDP socket from
whence it is leaked when that socket is closed.

When a network namespace is removed, the wait for dst records to be cleaned
up happens before the cleanup of the rxrpc and UDP socket, meaning that the
wait never finishes.

Fix this by moving the rxrpc (and, by dependence, the afs) private
per-network namespace registrations to the device group rather than subsys
group.  This allows cached rxrpc local endpoints to be cleared and their
UDP sockets closed before we try waiting for the dst records.

The symptom is that lines looking like the following:

	unregister_netdevice: waiting for lo to become free

get emitted at regular intervals after running something like the
referenced syzbot test.

Thanks to Vadim for tracking this down and work out the fix.

Reported-by: syzbot+df400f2f24a1677cd7e0@syzkaller.appspotmail.com
Reported-by: Vadim Fedorenko <vfedorenko@novek.ru>
Fixes: 5271953cad31 ("rxrpc: Use the UDP encap_rcv hook")
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vadim Fedorenko <vfedorenko@novek.ru>
Link: https://lore.kernel.org/r/161196443016.3868642.5577440140646403533.stgit@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-12 12:51:53 +08:00
Takeshi Misawa bb68f86796 rxrpc: Fix memory leak in rxrpc_lookup_local
commit b8323f7288abd71794cd7b11a4c0a38b8637c8b5 upstream.

Commit 9ebeddef58c4 ("rxrpc: rxrpc_peer needs to hold a ref on the rxrpc_local record")
Then release ref in __rxrpc_put_peer and rxrpc_put_peer_locked.

	struct rxrpc_peer *rxrpc_alloc_peer(struct rxrpc_local *local, gfp_t gfp)
	-               peer->local = local;
	+               peer->local = rxrpc_get_local(local);

rxrpc_discard_prealloc also need ref release in discarding.

syzbot report:
BUG: memory leak
unreferenced object 0xffff8881080ddc00 (size 256):
  comm "syz-executor339", pid 8462, jiffies 4294942238 (age 12.350s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 0a 00 00 00 00 c0 00 08 81 88 ff ff  ................
  backtrace:
    [<000000002b6e495f>] kmalloc include/linux/slab.h:552 [inline]
    [<000000002b6e495f>] kzalloc include/linux/slab.h:682 [inline]
    [<000000002b6e495f>] rxrpc_alloc_local net/rxrpc/local_object.c:79 [inline]
    [<000000002b6e495f>] rxrpc_lookup_local+0x1c1/0x760 net/rxrpc/local_object.c:244
    [<000000006b43a77b>] rxrpc_bind+0x174/0x240 net/rxrpc/af_rxrpc.c:149
    [<00000000fd447a55>] afs_open_socket+0xdb/0x200 fs/afs/rxrpc.c:64
    [<000000007fd8867c>] afs_net_init+0x2b4/0x340 fs/afs/main.c:126
    [<0000000063d80ec1>] ops_init+0x4e/0x190 net/core/net_namespace.c:152
    [<00000000073c5efa>] setup_net+0xde/0x2d0 net/core/net_namespace.c:342
    [<00000000a6744d5b>] copy_net_ns+0x19f/0x3e0 net/core/net_namespace.c:483
    [<0000000017d3aec3>] create_new_namespaces+0x199/0x4f0 kernel/nsproxy.c:110
    [<00000000186271ef>] unshare_nsproxy_namespaces+0x9b/0x120 kernel/nsproxy.c:226
    [<000000002de7bac4>] ksys_unshare+0x2fe/0x5c0 kernel/fork.c:2957
    [<00000000349b12ba>] __do_sys_unshare kernel/fork.c:3025 [inline]
    [<00000000349b12ba>] __se_sys_unshare kernel/fork.c:3023 [inline]
    [<00000000349b12ba>] __x64_sys_unshare+0x12/0x20 kernel/fork.c:3023
    [<000000006d178ef7>] do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
    [<00000000637076d4>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 9ebeddef58c4 ("rxrpc: rxrpc_peer needs to hold a ref on the rxrpc_local record")
Signed-off-by: Takeshi Misawa <jeliantsurux@gmail.com>
Reported-and-tested-by: syzbot+305326672fed51b205f7@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/161183091692.3506637.3206605651502458810.stgit@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:51:48 +08:00
David Howells 2140596847 rxrpc: Fix handling of an unsupported token type in rxrpc_read()
[ Upstream commit d52e419ac8b50c8bef41b398ed13528e75d7ad48 ]

Clang static analysis reports the following:

net/rxrpc/key.c:657:11: warning: Assigned value is garbage or undefined
                toksize = toksizes[tok++];
                        ^ ~~~~~~~~~~~~~~~

rxrpc_read() contains two consecutive loops.  The first loop calculates the
token sizes and stores the results in toksizes[] and the second one uses
the array.  When there is an error in identifying the token in the first
loop, the token is skipped, no change is made to the toksizes[] array.
When the same error happens in the second loop, the token is not skipped.
This will cause the toksizes[] array to be out of step and will overrun
past the calculated sizes.

Fix this by making both loops log a message and return an error in this
case.  This should only happen if a new token type is incompletely
implemented, so it should normally be impossible to trigger this.

Fixes: 9a059cd5ca7d ("rxrpc: Downgrade the BUG() for unsupported token type in rxrpc_read()")
Reported-by: Tom Rix <trix@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/161046503122.2445787.16714129930607546635.stgit@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:51:31 +08:00
Baptiste Lepers 402ee4bd13 rxrpc: Call state should be read with READ_ONCE() under some circumstances
[ Upstream commit a95d25dd7b94a5ba18246da09b4218f132fed60e ]

The call state may be changed at any time by the data-ready routine in
response to received packets, so if the call state is to be read and acted
upon several times in a function, READ_ONCE() must be used unless the call
state lock is held.

As it happens, we used READ_ONCE() to read the state a few lines above the
unmarked read in rxrpc_input_data(), so use that value rather than
re-reading it.

Fixes: a158bdd3247b ("rxrpc: Fix call timeouts")
Signed-off-by: Baptiste Lepers <baptiste.lepers@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/161046715522.2450566.488819910256264150.stgit@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:51:30 +08:00
David Howells 4391057c08 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>
2021-03-16 16:38:05 +08:00
David Howells 071ac21ba9 rxrpc: The server keyring isn't network-namespaced
[ Upstream commit fea99111244bae44e7d82a973744d27ea1567814 ]

The keyring containing the server's tokens isn't network-namespaced, so it
shouldn't be looked up with a network namespace.  It is expected to be
owned specifically by the server, so namespacing is unnecessary.

Fixes: a58946c158a0 ("keys: Pass the network namespace into request_key mechanism")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:38:05 +08:00
David Howells a1f3fcb5c1 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>
2021-03-16 16:38:05 +08:00
David Howells 3d6af126fb 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>
2021-03-16 16:38:05 +08:00
Marc Dionne cb4cd57f79 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>
2021-03-16 16:38:04 +08:00
David Howells 59db790da3 rxrpc: Make rxrpc_kernel_get_srtt() indicate validity
[ Upstream commit 1d4adfaf65746203861c72d9d78de349eb97d528 ]

Fix rxrpc_kernel_get_srtt() to indicate the validity of the returned
smoothed RTT.  If we haven't had any valid samples yet, the SRTT isn't
useful.

Fixes: c410bf01933e ("rxrpc: Fix the excessive initial retransmission timeout")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:35:28 +08:00
David Howells a9377c81f8 rxrpc: Keep the ACK serial in a var in rxrpc_input_ack()
[ Upstream commit 68528d937dcd675e79973061c1a314db598162d1 ]

Keep the ACK serial number in a variable in rxrpc_input_ack() as it's used
frequently.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:35:28 +08:00
David Howells 23fccff377 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>
2021-03-16 16:33:09 +08:00
David Howells a719c363e4 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>
2021-03-16 16:32:42 +08:00
David Howells 1338f7f759 rxrpc: Fix afs large storage transmission performance drop
[ Upstream commit 02c28dffb13abbaaedece1e4a6493b48ad3f913a ]

Commit 2ad6691d988c, which moved the modification of the status annotation
for a packet in the Tx buffer prior to the retransmission moved the state
clearance, but managed to lose the bit that set it to UNACK.

Consequently, if a retransmission occurs, the packet is accidentally
changed to the ACK state (ie. 0) by masking it off, which means that the
packet isn't counted towards the tally of newly-ACK'd packets if it gets
hard-ACK'd.  This then prevents the congestion control algorithm from
recovering properly.

Fix by reinstating the change of state to UNACK.

Spotted by the generic/460 xfstest.

Fixes: 2ad6691d988c ("rxrpc: Fix race between incoming ACK parser and retransmitter")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:31:17 +08:00
David Howells 64c0974b65 rxrpc: Fix race between incoming ACK parser and retransmitter
[ Upstream commit 2ad6691d988c0c611362ddc2aad89e0fb50e3261 ]

There's a race between the retransmission code and the received ACK parser.
The problem is that the retransmission loop has to drop the lock under
which it is iterating through the transmission buffer in order to transmit
a packet, but whilst the lock is dropped, the ACK parser can crank the Tx
window round and discard the packets from the buffer.

The retransmission code then updated the annotations for the wrong packet
and a later retransmission thought it had to retransmit a packet that
wasn't there, leading to a NULL pointer dereference.

Fix this by:

 (1) Moving the annotation change to before we drop the lock prior to
     transmission.  This means we can't vary the annotation depending on
     the outcome of the transmission, but that's fine - we'll retransmit
     again later if it failed now.

 (2) Skipping the packet if the skb pointer is NULL.

The following oops was seen:

	BUG: kernel NULL pointer dereference, address: 000000000000002d
	Workqueue: krxrpcd rxrpc_process_call
	RIP: 0010:rxrpc_get_skb+0x14/0x8a
	...
	Call Trace:
	 rxrpc_resend+0x331/0x41e
	 ? get_vtime_delta+0x13/0x20
	 rxrpc_process_call+0x3c0/0x4ac
	 process_one_work+0x18f/0x27f
	 worker_thread+0x1a3/0x247
	 ? create_worker+0x17d/0x17d
	 kthread+0xe6/0xeb
	 ? kthread_delayed_work_timer_fn+0x83/0x83
	 ret_from_fork+0x1f/0x30

Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
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>
2021-03-16 16:31:14 +08:00
David Howells 6526af8fdd 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>
2021-03-16 16:30:58 +08:00
David Howells 3ff709ca4c 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>
2021-03-16 16:30:47 +08:00
David Howells 0101545990 rxrpc: Adjust /proc/net/rxrpc/calls to display call->debug_id not user_ID
[ Upstream commit 32f71aa497cfb23d37149c2ef16ad71fce2e45e2 ]

The user ID value isn't actually much use - and leaks a kernel pointer or a
userspace value - so replace it with the call debug ID, which appears in trace
points.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:30:27 +08:00
David Howells 316421485d rxrpc: Fix ack discard
[ Upstream commit 441fdee1eaf050ef0040bde0d7af075c1c6a6d8b ]

The Rx protocol has a "previousPacket" field in it that is not handled in
the same way by all protocol implementations.  Sometimes it contains the
serial number of the last DATA packet received, sometimes the sequence
number of the last DATA packet received and sometimes the highest sequence
number so far received.

AF_RXRPC is using this to weed out ACKs that are out of date (it's possible
for ACK packets to get reordered on the wire), but this does not work with
OpenAFS which will just stick the sequence number of the last packet seen
into previousPacket.

The issue being seen is that big AFS FS.StoreData RPC (eg. of ~256MiB) are
timing out when partly sent.  A trace was captured, with an additional
tracepoint to show ACKs being discarded in rxrpc_input_ack().  Here's an
excerpt showing the problem.

 52873.203230: rxrpc_tx_data: c=000004ae DATA ed1a3584:00000002 0002449c q=00024499 fl=09

A DATA packet with sequence number 00024499 has been transmitted (the "q="
field).

 ...
 52873.243296: rxrpc_rx_ack: c=000004ae 00012a2b DLY r=00024499 f=00024497 p=00024496 n=0
 52873.243376: rxrpc_rx_ack: c=000004ae 00012a2c IDL r=0002449b f=00024499 p=00024498 n=0
 52873.243383: rxrpc_rx_ack: c=000004ae 00012a2d OOS r=0002449d f=00024499 p=0002449a n=2

The Out-Of-Sequence ACK indicates that the server didn't see DATA sequence
number 00024499, but did see seq 0002449a (previousPacket, shown as "p=",
skipped the number, but firstPacket, "f=", which shows the bottom of the
window is set at that point).

 52873.252663: rxrpc_retransmit: c=000004ae q=24499 a=02 xp=14581537
 52873.252664: rxrpc_tx_data: c=000004ae DATA ed1a3584:00000002 000244bc q=00024499 fl=0b *RETRANS*

The packet has been retransmitted.  Retransmission recurs until the peer
says it got the packet.

 52873.271013: rxrpc_rx_ack: c=000004ae 00012a31 OOS r=000244a1 f=00024499 p=0002449e n=6

More OOS ACKs indicate that the other packets that are already in the
transmission pipeline are being received.  The specific-ACK list is up to 6
ACKs and NAKs.

 ...
 52873.284792: rxrpc_rx_ack: c=000004ae 00012a49 OOS r=000244b9 f=00024499 p=000244b6 n=30
 52873.284802: rxrpc_retransmit: c=000004ae q=24499 a=0a xp=63505500
 52873.284804: rxrpc_tx_data: c=000004ae DATA ed1a3584:00000002 000244c2 q=00024499 fl=0b *RETRANS*
 52873.287468: rxrpc_rx_ack: c=000004ae 00012a4a OOS r=000244ba f=00024499 p=000244b7 n=31
 52873.287478: rxrpc_rx_ack: c=000004ae 00012a4b OOS r=000244bb f=00024499 p=000244b8 n=32

At this point, the server's receive window is full (n=32) with presumably 1
NAK'd packet and 31 ACK'd packets.  We can't transmit any more packets.

 52873.287488: rxrpc_retransmit: c=000004ae q=24499 a=0a xp=61327980
 52873.287489: rxrpc_tx_data: c=000004ae DATA ed1a3584:00000002 000244c3 q=00024499 fl=0b *RETRANS*
 52873.293850: rxrpc_rx_ack: c=000004ae 00012a4c DLY r=000244bc f=000244a0 p=00024499 n=25

And now we've received an ACK indicating that a DATA retransmission was
received.  7 packets have been processed (the occupied part of the window
moved, as indicated by f= and n=).

 52873.293853: rxrpc_rx_discard_ack: c=000004ae r=00012a4c 000244a0<00024499 00024499<000244b8

However, the DLY ACK gets discarded because its previousPacket has gone
backwards (from p=000244b8, in the ACK at 52873.287478 to p=00024499 in the
ACK at 52873.293850).

We then end up in a continuous cycle of retransmit/discard.  kafs fails to
update its window because it's discarding the ACKs and can't transmit an
extra packet that would clear the issue because the window is full.
OpenAFS doesn't change the previousPacket value in the ACKs because no new
DATA packets are received with a different previousPacket number.

Fix this by altering the discard check to only discard an ACK based on
previousPacket if there was no advance in the firstPacket.  This allows us
to transmit a new packet which will cause previousPacket to advance in the
next ACK.

The check, however, needs to allow for the possibility that previousPacket
may actually have had the serial number placed in it instead - in which
case it will go outside the window and we should ignore it.

Fixes: 1a2391c30c0b ("rxrpc: Fix detection of out of order acks")
Reported-by: Dave Botsch <botsch@cnf.cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:28:21 +08:00
David Howells 3b4289291a rxrpc: Trace discarded ACKs
[ Upstream commit d1f129470e6cb79b8b97fecd12689f6eb49e27fe ]

Add a tracepoint to track received ACKs that are discarded due to being
outside of the Tx window.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:28:21 +08:00
Qiushi Wu a606875020 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>
2021-03-16 16:28:20 +08:00
David Howells 24457be58e rxrpc: Fix the excessive initial retransmission timeout
commit c410bf01933e5e09d142c66c3df9ad470a7eec13 upstream.

rxrpc currently uses a fixed 4s retransmission timeout until the RTT is
sufficiently sampled.  This can cause problems with some fileservers with
calls to the cache manager in the afs filesystem being dropped from the
fileserver because a packet goes missing and the retransmission timeout is
greater than the call expiry timeout.

Fix this by:

 (1) Copying the RTT/RTO calculation code from Linux's TCP implementation
     and altering it to fit rxrpc.

 (2) Altering the various users of the RTT to make use of the new SRTT
     value.

 (3) Replacing the use of rxrpc_resend_timeout to use the calculated RTO
     value instead (which is needed in jiffies), along with a backoff.

Notes:

 (1) rxrpc provides RTT samples by matching the serial numbers on outgoing
     DATA packets that have the RXRPC_REQUEST_ACK set and PING ACK packets
     against the reference serial number in incoming REQUESTED ACK and
     PING-RESPONSE ACK packets.

 (2) Each packet that is transmitted on an rxrpc connection gets a new
     per-connection serial number, even for retransmissions, so an ACK can
     be cross-referenced to a specific trigger packet.  This allows RTT
     information to be drawn from retransmitted DATA packets also.

 (3) rxrpc maintains the RTT/RTO state on the rxrpc_peer record rather than
     on an rxrpc_call because many RPC calls won't live long enough to
     generate more than one sample.

 (4) The calculated SRTT value is in units of 8ths of a microsecond rather
     than nanoseconds.

The (S)RTT and RTO values are displayed in /proc/net/rxrpc/peers.

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:28:20 +08:00
David Howells 7cb109749e rxrpc: Fix DATA Tx to disable nofrag for UDP on AF_INET6 socket
commit 0e631eee17dcea576ab922fa70e4fdbd596ee452 upstream.

Fix the DATA packet transmission to disable nofrag for UDPv4 on an AF_INET6
socket as well as UDPv6 when trying to transmit fragmentably.

Without this, packets filled to the normal size used by the kernel AFS
client of 1412 bytes be rejected by udp_sendmsg() with EMSGSIZE
immediately.  The ->sk_error_report() notification hook is called, but
rxrpc doesn't generate a trace for it.

This is a temporary fix; a more permanent solution needs to involve
changing the size of the packets being filled in accordance with the MTU,
which isn't currently done in AF_RXRPC.  The reason for not doing so was
that, barring the last packet in an rx jumbo packet, jumbos can only be
assembled out of 1412-byte packets - and the plan was to construct jumbos
on the fly at transmission time.

Also, there's no point turning on IPV6_MTU_DISCOVER, since IPv6 has to
engage in this anyway since fragmentation is only done by the sender.  We
can then condense the switch-statement in rxrpc_send_data_packet().

Fixes: 75b54cb57ca3 ("rxrpc: Add IPv6 support")
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>
2021-03-16 16:27:08 +08:00
Waiman Long 13efd8129c 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>
2021-03-16 16:26:42 +08:00
David Howells 5ecd5d7bad rxrpc: Fix call interruptibility handling
[ Upstream commit e138aa7d3271ac1b0690ae2c9b04d51468dce1d6 ]

Fix the interruptibility of kernel-initiated client calls so that they're
either only interruptible when they're waiting for a call slot to come
available or they're not interruptible at all.  Either way, they're not
interruptible during transmission.

This should help prevent StoreData calls from being interrupted when
writeback is in progress.  It doesn't, however, handle interruption during
the receive phase.

Userspace-initiated calls are still interruptable.  After the signal has
been handled, sendmsg() will return the amount of data copied out of the
buffer and userspace can perform another sendmsg() call to continue
transmission.

Fixes: bc5e3a546d55 ("rxrpc: Use MSG_WAITALL to tell sendmsg() to temporarily ignore signals")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:25:53 +08:00
David Howells c965166da4 rxrpc: Abstract out the calculation of whether there's Tx space
[ Upstream commit 158fe6665389964a1de212818b4a5c52b7f7aff4 ]

Abstract out the calculation of there being sufficient Tx buffer space.
This is reproduced several times in the rxrpc sendmsg code.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:25:53 +08:00
Kaixu Xia 590eaf1fec Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
2021-03-16 11:01:34 +08:00