15 Oct, 2020
2 commits
-
Fix the loss of transmission of a call's final ack when a socket gets shut
down. This means that the server will retransmit the last data packet or
send a ping ack and then get an ICMP indicating the port got closed. The
server will then view this as a failure.Fixes: 3136ef49a14c ("rxrpc: Delay terminal ACK transmission on a client call")
Signed-off-by: David Howells -
Fix rxrpc_unbundle_conn() to not drop the bundle usage count when cleaning
up an exclusive connection.Based on the suggested fix from Hillf Danton.
Fixes: 245500d853e9 ("rxrpc: Rewrite the client connection manager")
Reported-by: syzbot+d57aaf84dd8a550e6d91@syzkaller.appspotmail.com
Signed-off-by: David Howells
cc: Hillf Danton
09 Oct, 2020
1 commit
-
Small conflict around locking in rxrpc_process_event() -
channel_lock moved to bundle in next, while state lock
needs _bh() from net.Signed-off-by: Jakub Kicinski
06 Oct, 2020
1 commit
-
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
05 Oct, 2020
5 commits
-
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 -
When a new incoming call arrives at an userspace rxrpc socket on a new
connection that has a security class set, the code currently pushes it onto
the accept queue to hold a ref on it for the socket. This doesn't work,
however, as recvmsg() pops it off, notices that it's in the SERVER_SECURING
state and discards the ref. This means that the call runs out of refs too
early and the kernel oopses.By contrast, a kernel rxrpc socket manually pre-charges the incoming call
pool with calls that already have user call IDs assigned, so they are ref'd
by the call tree on the socket.Change the mode of operation for userspace rxrpc server sockets to work
like this too. Although this is a UAPI change, server sockets aren't
currently functional.Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
Signed-off-by: David Howells -
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 -
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 -
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
Signed-off-by: David Howells
14 Sep, 2020
4 commits
-
When setting up a client connection, a second ref is accidentally obtained
on the connection bundle (we get one when allocating the conn and a second
one when adding the conn to the bundle).Fix it to only use the ref obtained by rxrpc_alloc_client_connection() and
not to add a second when adding the candidate conn to the bundle.Fixes: 245500d853e9 ("rxrpc: Rewrite the client connection manager")
Signed-off-by: David Howells -
When the network namespace exits, rxrpc_clean_up_local_conns() needs to
unbundle each client connection it evicts. Fix it to do this.kernel BUG at net/rxrpc/conn_object.c:481!
RIP: 0010:rxrpc_destroy_all_connections.cold+0x11/0x13 net/rxrpc/conn_object.c:481
Call Trace:
rxrpc_exit_net+0x1a4/0x2e0 net/rxrpc/net_ns.c:119
ops_exit_list+0xb0/0x160 net/core/net_namespace.c:186
cleanup_net+0x4ea/0xa00 net/core/net_namespace.c:603
process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
kthread+0x3b5/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294Fixes: 245500d853e9 ("rxrpc: Rewrite the client connection manager")
Reported-by: syzbot+52071f826a617b9c76ed@syzkaller.appspotmail.com
Signed-off-by: David Howells -
The alloc_error field in the rxrpc_bundle struct should be signed as it has
negative error codes assigned to it. Checks directly on it may then fail,
and may produce a warning like this:net/rxrpc/conn_client.c:662 rxrpc_wait_for_channel()
warn: 'bundle->alloc_error' is unsignedFixes: 245500d853e9 ("rxrpc: Rewrite the client connection manager")
Reported-by Dan Carpenter
Signed-off-by: David Howells -
Fix an error-handling goto in rxrpc_connect_call() whereby it will jump to
free the bundle it failed to allocate.Fixes: 245500d853e9 ("rxrpc: Rewrite the client connection manager")
Reported-by: kernel test robot
Reported-by: Dan Carpenter
Signed-off-by: David Howells
09 Sep, 2020
3 commits
-
Allow the number of parallel connections to a machine to be expanded from a
single connection to a maximum of four. This allows up to 16 calls to be
in progress at the same time to any particular peer instead of 4.Signed-off-by: David Howells
-
Rewrite the rxrpc client connection manager so that it can support multiple
connections for a given security key to a peer. The following changes are
made:(1) For each open socket, the code currently maintains an rbtree with the
connections placed into it, keyed by communications parameters. This
is tricky to maintain as connections can be culled from the tree or
replaced within it. Connections can require replacement for a number
of reasons, e.g. their IDs span too great a range for the IDR data
type to represent efficiently, the call ID numbers on that conn would
overflow or the conn got aborted.This is changed so that there's now a connection bundle object placed
in the tree, keyed on the same parameters. The bundle, however, does
not need to be replaced.(2) An rxrpc_bundle object can now manage the available channels for a set
of parallel connections. The lock that manages this is moved there
from the rxrpc_connection struct (channel_lock).(3) There'a a dummy bundle for all incoming connections to share so that
they have a channel_lock too. It might be better to give each
incoming connection its own bundle. This bundle is not needed to
manage which channels incoming calls are made on because that's the
solely at whim of the client.(4) The restrictions on how many client connections are around are
removed. Instead, a previous patch limits the number of client calls
that can be allocated. Ordinarily, client connections are reaped
after 2 minutes on the idle queue, but when more than a certain number
of connections are in existence, the reaper starts reaping them after
2s of idleness instead to get the numbers back down.It could also be made such that new call allocations are forced to
wait until the number of outstanding connections subsides.Signed-off-by: David Howells
-
Impose a maximum on the number of client rxrpc calls that are allowed
simultaneously. This will be in lieu of a maximum number of client
connections as this is easier to administed as, unlike connections, calls
aren't reusable (to be changed in a subsequent patch)..This doesn't affect the limits on service calls and connections.
Signed-off-by: David Howells
08 Sep, 2020
1 commit
-
rxrpc_min_rtt_wlen is never used after it was introduced.
So better to remove it.Reported-by: Hulk Robot
Signed-off-by: Wang Hai
Signed-off-by: Jakub Kicinski
04 Sep, 2020
1 commit
-
Pull networking fixes from David Miller:
1) Use netif_rx_ni() when necessary in batman-adv stack, from Jussi
Kivilinna.2) Fix loss of RTT samples in rxrpc, from David Howells.
3) Memory leak in hns_nic_dev_probe(), from Dignhao Liu.
4) ravb module cannot be unloaded, fix from Yuusuke Ashizuka.
5) We disable BH for too lokng in sctp_get_port_local(), add a
cond_resched() here as well, from Xin Long.6) Fix memory leak in st95hf_in_send_cmd, from Dinghao Liu.
7) Out of bound access in bpf_raw_tp_link_fill_link_info(), from
Yonghong Song.8) Missing of_node_put() in mt7530 DSA driver, from Sumera
Priyadarsini.9) Fix crash in bnxt_fw_reset_task(), from Michael Chan.
10) Fix geneve tunnel checksumming bug in hns3, from Yi Li.
11) Memory leak in rxkad_verify_response, from Dinghao Liu.
12) In tipc, don't use smp_processor_id() in preemptible context. From
Tuong Lien.13) Fix signedness issue in mlx4 memory allocation, from Shung-Hsi Yu.
14) Missing clk_disable_prepare() in gemini driver, from Dan Carpenter.
15) Fix ABI mismatch between driver and firmware in nfp, from Louis
Peens.* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (110 commits)
net/smc: fix sock refcounting in case of termination
net/smc: reset sndbuf_desc if freed
net/smc: set rx_off for SMCR explicitly
net/smc: fix toleration of fake add_link messages
tg3: Fix soft lockup when tg3_reset_task() fails.
doc: net: dsa: Fix typo in config code sample
net: dp83867: Fix WoL SecureOn password
nfp: flower: fix ABI mismatch between driver and firmware
tipc: fix shutdown() of connectionless socket
ipv6: Fix sysctl max for fib_multipath_hash_policy
drivers/net/wan/hdlc: Change the default of hard_header_len to 0
net: gemini: Fix another missing clk_disable_unprepare() in probe
net: bcmgenet: fix mask check in bcmgenet_validate_flow()
amd-xgbe: Add support for new port mode
net: usb: dm9601: Add USB ID of Keenetic Plus DSL
vhost: fix typo in error message
net: ethernet: mlx4: Fix memory allocation in mlx4_buddy_init()
pktgen: fix error message with wrong function name
net: ethernet: ti: am65-cpsw: fix rmii 100Mbit link mode
cxgb4: fix thermal zone device registration
...
28 Aug, 2020
1 commit
-
Fix a memory leak in rxkad_verify_response() whereby the response buffer
doesn't get freed if we fail to allocate a ticket buffer.Fixes: ef68622da9cc ("rxrpc: Handle temporary errors better in rxkad security")
Signed-off-by: Dinghao Liu
Signed-off-by: David Howells
Signed-off-by: David S. Miller
24 Aug, 2020
1 commit
-
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through
Signed-off-by: Gustavo A. R. Silva
21 Aug, 2020
2 commits
-
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 -
The Rx protocol has a mechanism to help generate RTT samples that works by
a client transmitting a REQUESTED-type ACK when it receives a DATA packet
that has the REQUEST_ACK flag set.The peer, however, may interpose other ACKs before transmitting the
REQUESTED-ACK, as can be seen in the following trace excerpt:rxrpc_tx_data: c=00000044 DATA d0b5ece8:00000001 00000001 q=00000001 fl=07
rxrpc_rx_ack: c=00000044 00000001 PNG r=00000000 f=00000002 p=00000000 n=0
rxrpc_rx_ack: c=00000044 00000002 REQ r=00000001 f=00000002 p=00000001 n=0
...DATA packet 1 (q=xx) has REQUEST_ACK set (bit 1 of fl=xx). The incoming
ping (labelled PNG) hard-acks the request DATA packet (f=xx exceeds the
sequence number of the DATA packet), causing it to be discarded from the Tx
ring. The ACK that was requested (labelled REQ, r=xx references the serial
of the DATA packet) comes after the ping, but the sk_buff holding the
timestamp has gone and the RTT sample is lost.This is particularly noticeable on RPC calls used to probe the service
offered by the peer. A lot of peers end up with an unknown RTT because we
only ever sent a single RPC. This confuses the server rotation algorithm.Fix this by caching the information about the outgoing packet in RTT
calculations in the rxrpc_call struct rather than looking in the Tx ring.A four-deep buffer is maintained and both REQUEST_ACK-flagged DATA and
PING-ACK transmissions are recorded in there. When the appropriate
response ACK is received, the buffer is checked for a match and, if found,
an RTT sample is recorded.If a received ACK refers to a packet with a later serial number than an
entry in the cache, that entry is presumed lost and the entry is made
available to record a new transmission.ACKs types other than REQUESTED-type and PING-type cause any matching
sample to be cancelled as they don't necessarily represent a useful
measurement.If there's no space in the buffer on ping/data transmission, the sample
base is discarded.Fixes: 50235c4b5a2f ("rxrpc: Obtain RTT data by requesting ACKs on DATA packets")
Signed-off-by: David Howells
20 Aug, 2020
1 commit
-
Keep the ACK serial number in a variable in rxrpc_input_ack() as it's used
frequently.Signed-off-by: David Howells
02 Aug, 2020
1 commit
-
Resolved kernel/bpf/btf.c using instructions from merge commit
69138b34a7248d2396ab85c8652e20c0c39beabaSigned-off-by: David S. Miller
31 Jul, 2020
1 commit
-
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+0x44/0xa9Fixes: 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
Reviewed-by: Marc Dionne
Signed-off-by: David S. Miller
26 Jul, 2020
1 commit
-
The UDP reuseport conflict was a little bit tricky.
The net-next code, via bpf-next, extracted the reuseport handling
into a helper so that the BPF sk lookup code could invoke it.At the same time, the logic for reuseport handling of unconnected
sockets changed via commit efc6b6f6c3113e8b203b9debfb72d81e0f3dcace
which changed the logic to carry on the reuseport result into the
rest of the lookup loop if we do not return immediately.This requires moving the reuseport_has_conns() logic into the callers.
While we are here, get rid of inline directives as they do not belong
in foo.c files.The other changes were cases of more straightforward overlapping
modifications.Signed-off-by: David S. Miller
25 Jul, 2020
1 commit
-
Rework the remaining setsockopt code to pass a sockptr_t instead of a
plain user pointer. This removes the last remaining set_fs(KERNEL_DS)
outside of architecture specific code.Signed-off-by: Christoph Hellwig
Acked-by: Stefan Schmidt [ieee802154]
Acked-by: Matthieu Baerts
Signed-off-by: David S. Miller
21 Jul, 2020
1 commit
-
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
Signed-off-by: David S. Miller
14 Jul, 2020
1 commit
-
Simple fixes which require no deep knowledge of the code.
Cc: David Howells
Signed-off-by: Andrew Lunn
Signed-off-by: David S. Miller
21 Jun, 2020
1 commit
-
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/u4:1/21CPU: 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:293Allocated 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+0x44/0xa9Freed 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:293The 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 detectedMemory 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
Signed-off-by: David S. Miller
18 Jun, 2020
2 commits
-
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 -
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
12 Jun, 2020
1 commit
-
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/0x30Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
Signed-off-by: David Howells
Signed-off-by: David S. Miller
09 Jun, 2020
1 commit
-
David Howells says:
====================
rxrpc: Fix hang due to missing notificationHere's a fix for AF_RXRPC. Occasionally calls hang because there are
circumstances in which rxrpc generate a notification when a call is
completed - primarily because initial packet transmission failed and the
call was killed off and an error returned. But the AFS filesystem driver
doesn't check this under all circumstances, expecting failure to be
delivered by asynchronous notification.There are two patches: the first moves the problematic bits out-of-line and
the second contains the fix.
====================Signed-off-by: David S. Miller
06 Jun, 2020
1 commit
-
Pull AFS updates from David Howells:
"There's some core VFS changes which affect a couple of filesystems:- Make the inode hash table RCU safe and providing some RCU-safe
accessor functions. The search can then be done without taking the
inode_hash_lock. Care must be taken because the object may be being
deleted and no wait is made.- Allow iunique() to avoid taking the inode_hash_lock.
- Allow AFS's callback processing to avoid taking the inode_hash_lock
when using the inode table to find an inode to notify.- Improve Ext4's time updating. Konstantin Khlebnikov said "For now,
I've plugged this issue with try-lock in ext4 lazy time update.
This solution is much better."Then there's a set of changes to make a number of improvements to the
AFS driver:- Improve callback (ie. third party change notification) processing
by:(a) Relying more on the fact we're doing this under RCU and by
using fewer locks. This makes use of the RCU-based inode
searching outlined above.(b) Moving to keeping volumes in a tree indexed by volume ID
rather than a flat list.(c) Making the server and volume records logically part of the
cell. This means that a server record now points directly at
the cell and the tree of volumes is there. This removes an N:M
mapping table, simplifying things.- Improve keeping NAT or firewall channels open for the server
callbacks to reach the client by actively polling the fileserver on
a timed basis, instead of only doing it when we have an operation
to process.- Improving detection of delayed or lost callbacks by including the
parent directory in the list of file IDs to be queried when doing a
bulk status fetch from lookup. We can then check to see if our copy
of the directory has changed under us without us getting notified.- Determine aliasing of cells (such as a cell that is pointed to be a
DNS alias). This allows us to avoid having ambiguity due to
apparently different cells using the same volume and file servers.- Improve the fileserver rotation to do more probing when it detects
that all of the addresses to a server are listed as non-responsive.
It's possible that an address that previously stopped responding
has become responsive again.Beyond that, lay some foundations for making some calls asynchronous:
- Turn the fileserver cursor struct into a general operation struct
and hang the parameters off of that rather than keeping them in
local variables and hang results off of that rather than the call
struct.- Implement some general operation handling code and simplify the
callers of operations that affect a volume or a volume component
(such as a file). Most of the operation is now done by core code.- Operations are supplied with a table of operations to issue
different variants of RPCs and to manage the completion, where all
the required data is held in the operation object, thereby allowing
these to be called from a workqueue.- Put the standard "if (begin), while(select), call op, end" sequence
into a canned function that just emulates the current behaviour for
now.There are also some fixes interspersed:
- Don't let the EACCES from ICMP6 mapping reach the user as such,
since it's confusing as to whether it's a filesystem error. Convert
it to EHOSTUNREACH.- Don't use the epoch value acquired through probing a server. If we
have two servers with the same UUID but in different cells, it's
hard to draw conclusions from them having different epoch values.- Don't interpret the argument to the CB.ProbeUuid RPC as a
fileserver UUID and look up a fileserver from it.- Deal with servers in different cells having the same UUIDs. In the
event that a CB.InitCallBackState3 RPC is received, we have to
break the callback promises for every server record matching that
UUID.- Don't let afs_statfs return values that go below 0.
- Don't use running fileserver probe state to make server selection
and address selection decisions on. Only make decisions on final
state as the running state is cleared at the start of probing"Acked-by: Al Viro (fs/inode.c part)
* tag 'afs-next-20200604' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (27 commits)
afs: Adjust the fileserver rotation algorithm to reprobe/retry more quickly
afs: Show more a bit more server state in /proc/net/afs/servers
afs: Don't use probe running state to make decisions outside probe code
afs: Fix afs_statfs() to not let the values go below zero
afs: Fix the by-UUID server tree to allow servers with the same UUID
afs: Reorganise volume and server trees to be rooted on the cell
afs: Add a tracepoint to track the lifetime of the afs_volume struct
afs: Detect cell aliases 3 - YFS Cells with a canonical cell name op
afs: Detect cell aliases 2 - Cells with no root volumes
afs: Detect cell aliases 1 - Cells with root volumes
afs: Implement client support for the YFSVL.GetCellName RPC op
afs: Retain more of the VLDB record for alias detection
afs: Fix handling of CB.ProbeUuid cache manager op
afs: Don't get epoch from a server because it may be ambiguous
afs: Build an abstraction around an "operation" concept
afs: Rename struct afs_fs_cursor to afs_operation
afs: Remove the error argument from afs_protocol_error()
afs: Set error flag rather than return error from file status decode
afs: Make callback processing more efficient.
afs: Show more information in /proc/net/afs/servers
...
05 Jun, 2020
2 commits
-
Under some circumstances, rxrpc will fail a transmit a packet through the
underlying UDP socket (ie. UDP sendmsg returns an error). This may result
in a call getting stuck.In the instance being seen, where AFS tries to send a probe to the Volume
Location server, tracepoints show the UDP Tx failure (in this case returing
error 99 EADDRNOTAVAIL) and then nothing more:afs_make_vl_call: c=0000015d VL.GetCapabilities
rxrpc_call: c=0000015d NWc u=1 sp=rxrpc_kernel_begin_call+0x106/0x170 [rxrpc] a=00000000dd89ee8a
rxrpc_call: c=0000015d Gus u=2 sp=rxrpc_new_client_call+0x14f/0x580 [rxrpc] a=00000000e20e4b08
rxrpc_call: c=0000015d SEE u=2 sp=rxrpc_activate_one_channel+0x7b/0x1c0 [rxrpc] a=00000000e20e4b08
rxrpc_call: c=0000015d CON u=2 sp=rxrpc_kernel_begin_call+0x106/0x170 [rxrpc] a=00000000e20e4b08
rxrpc_tx_fail: c=0000015d r=1 ret=-99 CallDataNofragThe problem is that if the initial packet fails and the retransmission
timer hasn't been started, the call is set to completed and an error is
returned from rxrpc_send_data_packet() to rxrpc_queue_packet(). Though
rxrpc_instant_resend() is called, this does nothing because the call is
marked completed.So rxrpc_notify_socket() isn't called and the error is passed back up to
rxrpc_send_data(), rxrpc_kernel_send_data() and thence to afs_make_call()
and afs_vl_get_capabilities() where it is simply ignored because it is
assumed that the result of a probe will be collected asynchronously.Fileserver probing is similarly affected via afs_fs_get_capabilities().
Fix this by always issuing a notification in __rxrpc_set_call_completion()
if it shifts a call to the completed state, even if an error is also
returned to the caller through the function return value.Also put in a little bit of optimisation to avoid taking the call
state_lock and disabling softirqs if the call is already in the completed
state and remove some now redundant rxrpc_notify_socket() calls.Fixes: f5c17aaeb2ae ("rxrpc: Calls should only have one terminal state")
Reported-by: Gerry Seidman
Signed-off-by: David Howells
Reviewed-by: Marc Dionne -
Move the handling of call completion out of line so that the next patch can
add more code in that area.Signed-off-by: David Howells
Reviewed-by: Marc Dionne
31 May, 2020
2 commits
-
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
-
Map the EACCES error that is produced by some ICMP6 packets to EHOSTUNREACH
when we get them as EACCES has other meanings within a filesystem context.Signed-off-by: David Howells
29 May, 2020
1 commit
-
Add a helper to directly set the RXRPC_MIN_SECURITY_LEVEL sockopt from
kernel space without going through a fake uaccess.Thanks to David Howells for the documentation updates.
Signed-off-by: Christoph Hellwig
Acked-by: David Howells
Signed-off-by: David S. Miller