The internal recvmsg() functions have two parameters 'flags' and 'noblock'
that were merged inside skb_recv_datagram(). As a follow up patch to commit
f4b41f062c ("net: remove noblock parameter from skb_recv_datagram()")
this patch removes the separate 'noblock' parameter for recvmsg().
Analogue to the referenced patch for skb_recv_datagram() the 'flags' and
'noblock' parameters are unnecessarily split up with e.g.
err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
flags & ~MSG_DONTWAIT, &addr_len);
or in
err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg,
sk, msg, size, flags & MSG_DONTWAIT,
flags & ~MSG_DONTWAIT, &addr_len);
instead of simply using only flags all the time and check for MSG_DONTWAIT
where needed (to preserve for the formerly separated no(n)block condition).
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20220411124955.154876-1-socketcan@hartkopp.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The same fix in commit 5ec7d18d18 ("sctp: use call_rcu to free endpoint")
is also needed for dumping one asoc and sock after the lookup.
Fixes: 86fdb3448c ("sctp: ensure ep is not destroyed before doing the dump")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
commit 077cdda764 ("net/mlx5e: TC, Fix memory leak with rules with internal port")
commit 31108d142f ("net/mlx5: Fix some error handling paths in 'mlx5e_tc_add_fdb_flow()'")
commit 4390c6edc0 ("net/mlx5: Fix some error handling paths in 'mlx5e_tc_add_fdb_flow()'")
https://lore.kernel.org/all/20211229065352.30178-1-saeed@kernel.org/
net/smc/smc_wr.c
commit 49dc9013e3 ("net/smc: Use the bitmap API when applicable")
commit 349d43127d ("net/smc: fix kernel panic caused by race of smc_sock")
bitmap_zero()/memset() is removed by the fix
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch is to delay the endpoint free by calling call_rcu() to fix
another use-after-free issue in sctp_sock_dump():
BUG: KASAN: use-after-free in __lock_acquire+0x36d9/0x4c20
Call Trace:
__lock_acquire+0x36d9/0x4c20 kernel/locking/lockdep.c:3218
lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:168
spin_lock_bh include/linux/spinlock.h:334 [inline]
__lock_sock+0x203/0x350 net/core/sock.c:2253
lock_sock_nested+0xfe/0x120 net/core/sock.c:2774
lock_sock include/net/sock.h:1492 [inline]
sctp_sock_dump+0x122/0xb20 net/sctp/diag.c:324
sctp_for_each_transport+0x2b5/0x370 net/sctp/socket.c:5091
sctp_diag_dump+0x3ac/0x660 net/sctp/diag.c:527
__inet_diag_dump+0xa8/0x140 net/ipv4/inet_diag.c:1049
inet_diag_dump+0x9b/0x110 net/ipv4/inet_diag.c:1065
netlink_dump+0x606/0x1080 net/netlink/af_netlink.c:2244
__netlink_dump_start+0x59a/0x7c0 net/netlink/af_netlink.c:2352
netlink_dump_start include/linux/netlink.h:216 [inline]
inet_diag_handler_cmd+0x2ce/0x3f0 net/ipv4/inet_diag.c:1170
__sock_diag_cmd net/core/sock_diag.c:232 [inline]
sock_diag_rcv_msg+0x31d/0x410 net/core/sock_diag.c:263
netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2477
sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:274
This issue occurs when asoc is peeled off and the old sk is freed after
getting it by asoc->base.sk and before calling lock_sock(sk).
To prevent the sk free, as a holder of the sk, ep should be alive when
calling lock_sock(). This patch uses call_rcu() and moves sock_put and
ep free into sctp_endpoint_destroy_rcu(), so that it's safe to try to
hold the ep under rcu_read_lock in sctp_transport_traverse_process().
If sctp_endpoint_hold() returns true, it means this ep is still alive
and we have held it and can continue to dump it; If it returns false,
it means this ep is dead and can be freed after rcu_read_unlock, and
we should skip it.
In sctp_sock_dump(), after locking the sk, if this ep is different from
tsp->asoc->ep, it means during this dumping, this asoc was peeled off
before calling lock_sock(), and the sk should be skipped; If this ep is
the same with tsp->asoc->ep, it means no peeloff happens on this asoc,
and due to lock_sock, no peeloff will happen either until release_sock.
Note that delaying endpoint free won't delay the port release, as the
port release happens in sctp_endpoint_destroy() before calling call_rcu().
Also, freeing endpoint by call_rcu() makes it safe to access the sk by
asoc->base.sk in sctp_assocs_seq_show() and sctp_rcv().
Thanks Jones to bring this issue up.
v1->v2:
- improve the changelog.
- add kfree(ep) into sctp_endpoint_destroy_rcu(), as Jakub noticed.
Reported-by: syzbot+9276d76e83e3bcde6c99@syzkaller.appspotmail.com
Reported-by: Lee Jones <lee.jones@linaro.org>
Fixes: d25adbeb0c ("sctp: fix an use-after-free issue in sctp_sock_dump")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Struct sctp_ep_common is included in both asoc and ep, but hlist_node
and hashent are only needed by ep after asoc_hashtable was dropped by
Commit b5eff71283 ("sctp: drop the old assoc hashtable of sctp").
So it is better to move hlist_node and hashent from sctp_ep_common to
sctp_endpoint, and it saves some space for each asoc.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, the probe timer is reused as the raise timer when PLPMTUD is in
the Search Complete state. raise_count was introduced to count how many
times the probe timer has timed out. When raise_count reaches to 30, the
raise timer handler will be triggered.
During the whole processing above, the timer keeps timing out every probe_
interval. It is a waste for the Search Complete state, as the raise timer
only needs to time out after 30 * probe_interval.
Since the raise timer and probe timer are never used at the same time, it
is no need to keep probe timer 'alive' in the Search Complete state. This
patch to introduce sctp_transport_reset_raise_timer() to start the timer
as the raise timer when entering the Search Complete state. When entering
the other states, sctp_transport_reset_probe_timer() will still be called
to reset the timer to the probe timer.
raise_count can be removed from sctp_transport as no need to count probe
timer timeout for raise timer timeout. last_rtx_chunks can be removed as
sctp_transport_reset_probe_timer() can be called in the place where asoc
rtx_data_chunks is changed.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Link: https://lore.kernel.org/r/edb0e48988ea85997488478b705b11ddc1ba724a.1637781974.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch is to move secid and peer_secid from endpoint to association,
and pass asoc to sctp_assoc_request and sctp_sk_clone instead of ep. As
ep is the local endpoint and asoc represents a connection, and in SCTP
one sk/ep could have multiple asoc/connection, saving secid/peer_secid
for new asoc will overwrite the old asoc's.
Note that since asoc can be passed as NULL, security_sctp_assoc_request()
is moved to the place right after the new_asoc is created in
sctp_sf_do_5_1B_init() and sctp_sf_do_unexpected_init().
v1->v2:
- fix the description of selinux_netlbl_skbuff_setsid(), as Jakub noticed.
- fix the annotation in selinux_sctp_assoc_request(), as Richard Noticed.
Fixes: 72e89f5008 ("security: Add support for SCTP security hooks")
Reported-by: Prashanth Prahlad <pprahlad@redhat.com>
Reviewed-by: Richard Haines <richard_c_haines@btinternet.com>
Tested-by: Richard Haines <richard_c_haines@btinternet.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sctp_transport_pl_hlen() is called to calculate the outer header length
for PL. However, as the Figure in rfc8899#section-4.4:
Any additional
headers .--- MPS -----.
| | |
v v v
+------------------------------+
| IP | ** | PL | protocol data |
+------------------------------+
<----- PLPMTU ----->
<---------- PMTU -------------->
Outer header are IP + Any additional headers, which doesn't include
Packetization Layer itself header, namely sctphdr, whereas sctphdr
is counted by __sctp_mtu_payload().
The incorrect calculation caused the link pathmtu to be set larger
than expected by t->pl.pmtu + sctp_transport_pl_hlen(). This patch
is to fix it by subtracting sctphdr len in sctp_transport_pl_hlen().
Fixes: d9e2e410ae ("sctp: add the constants/variables and states and some APIs for transport")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sctp_transport_pl_update() is called when transport update its dst and
pathmtu, instead of stopping the PLPMTUD probe timer, PLPMTUD should
start over and reset the probe timer. Otherwise, the PLPMTUD service
would stop.
Fixes: 92548ec2f1 ("sctp: add the probe timer in transport for PLPMTUD")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
transport encap_port update should be updated when sctp_vtag_verify()
succeeds, namely, returns 1, not returns 0. Correct it in this patch.
While at it, also fix the indentation.
Fixes: a1dd2cf2f1 ("sctp: allow changing transport encap_port by peer packets")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is to introduce last_rtx_chunks into sctp_transport to detect
if there's any packet retransmission/loss happened by checking against
asoc's rtx_data_chunks in sctp_transport_pl_send().
If there is, namely, transport->last_rtx_chunks != asoc->rtx_data_chunks,
the pmtu probe will be sent out. Otherwise, increment the pl.raise_count
and return when it's in Search Complete state.
With this patch, if in Search Complete state, which is a long period, it
doesn't need to keep probing the current pmtu unless there's data packet
loss. This will save quite some traffic.
v1->v2:
- add the missing Fixes tag.
Fixes: 0dac127c05 ("sctp: do black hole detection in search complete state")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch does 3 things:
- make sctp_transport_pl_send() and sctp_transport_pl_recv()
return bool type to decide if more probe is needed to send.
- pr_debug() only when probe is really needed to send.
- count pl.raise_count in sctp_transport_pl_send() instead of
sctp_transport_pl_recv(), and it's only incremented for the
1st probe for the same size.
These are preparations for the next patch to make probes happen
only when there's packet loss in Search Complete state.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Trivial conflict in net/netfilter/nf_tables_api.c.
Duplicate fix in tools/testing/selftests/net/devlink_port_split.py
- take the net-next version.
skmsg, and L4 bpf - keep the bpf code but remove the flags
and err params.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Ilja reported that, simply putting it, nothing was validating that
from_addr_param functions were operating on initialized memory. That is,
the parameter itself was being validated by sctp_walk_params, but it
doesn't check for types and their specific sizes and it could be a 0-length
one, causing from_addr_param to potentially work over the next parameter or
even uninitialized memory.
The fix here is to, in all calls to from_addr_param, check if enough space
is there for the wanted IP address type.
Reported-by: Ilja Van Sprundel <ivansprundel@ioactive.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently the PLPMUTD probe will stop for a long period (interval * 30)
after it enters search complete state. If there's a pmtu change on the
route path, it takes a long time to be aware if the ICMP TooBig packet
is lost or filtered.
As it says in rfc8899#section-4.3:
"A DPLPMTUD method MUST NOT rely solely on this method."
(ICMP PTB message).
This patch is to enable the other method for search complete state:
"A PL can use the DPLPMTUD probing mechanism to periodically
generate probe packets of the size of the current PLPMTU."
With this patch, the probe will continue with the current pmtu every
'interval' until the PMTU_RAISE_TIMER 'timeout', which we implement
by adding raise_count to raise the probe size when it counts to 30
and removing the SCTP_PL_COMPLETE check for PMTU_RAISE_TIMER.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previously, sctp over udp was using udp tunnel's icmp err process, which
only does sk lookup on sctp side. However for sctp's icmp error process,
there are more things to do, like syncing assoc pmtu/retransmit packets
for toobig type err, and starting proto_unreach_timer for unreach type
err etc.
Now after adding PLPMTUD, which also requires to process toobig type err
on sctp side. This patch is to process icmp err on sctp side by parsing
the type/code/info in .encap_err_lookup and call sctp's icmp processing
functions. Note as the 'redirect' err process needs to know the outer
ip(v6) header's, we have to leave it to udp(v6)_err to handle it.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As described in rfc8899#section-5.2, when a probe succeeds, there might
be the following state transitions:
- Base -> Search, occurs when probe succeeds with BASE_PLPMTU,
pl.pmtu is not changing,
pl.probe_size increases by SCTP_PL_BIG_STEP,
- Error -> Search, occurs when probe succeeds with BASE_PLPMTU,
pl.pmtu is changed from SCTP_MIN_PLPMTU to SCTP_BASE_PLPMTU,
pl.probe_size increases by SCTP_PL_BIG_STEP.
- Search -> Search Complete, occurs when probe succeeds with the probe
size SCTP_MAX_PLPMTU less than pl.probe_high,
pl.pmtu is not changing, but update *pathmtu* with it,
pl.probe_size is set back to pl.pmtu to double check it.
- Search Complete -> Search, occurs when probe succeeds with the probe
size equal to pl.pmtu,
pl.pmtu is not changing,
pl.probe_size increases by SCTP_PL_MIN_STEP.
So search process can be described as:
1. When it just enters 'Search' state, *pathmtu* is not updated with
pl.pmtu, and probe_size increases by a big step (SCTP_PL_BIG_STEP)
each round.
2. Until pl.probe_high is set when a probe fails, and probe_size
decreases back to pl.pmtu, as described in the last patch.
3. When the probe with the new size succeeds, probe_size changes to
increase by a small step (SCTP_PL_MIN_STEP) due to pl.probe_high
is set.
4. Until probe_size is next to pl.probe_high, the searching finishes and
it goes to 'Complete' state and updates *pathmtu* with pl.pmtu, and
then probe_size is set to pl.pmtu to confirm by once more probe.
5. This probe occurs after "30 * probe_inteval", a much longer time than
that in Search state. Once it is done it goes to 'Search' state again
with probe_size increased by SCTP_PL_MIN_STEP.
As we can see above, during the searching, pl.pmtu changes while *pathmtu*
doesn't. *pathmtu* is only updated when the search finishes by which it
gets an optimal value for it. A big step is used at the beginning until
it gets close to the optimal value, then it changes to a small step until
it has this optimal value.
The small step is also used in 'Complete' until it goes to 'Search' state
again and the probe with 'pmtu + the small step' succeeds, which means a
higher size could be used. Then probe_size changes to increase by a big
step again until it gets close to the next optimal value.
Note that anytime when black hole is detected, it goes directly to 'Base'
state with pl.pmtu set to SCTP_BASE_PLPMTU, as described in the last patch.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The state transition is described in rfc8899#section-5.2,
PROBE_COUNT == MAX_PROBES means the probe fails for MAX times, and the
state transition includes:
- Base -> Error, occurs when BASE_PLPMTU Confirmation Fails,
pl.pmtu is set to SCTP_MIN_PLPMTU,
probe_size is still SCTP_BASE_PLPMTU;
- Search -> Base, occurs when Black Hole Detected,
pl.pmtu is set to SCTP_BASE_PLPMTU,
probe_size is set back to SCTP_BASE_PLPMTU;
- Search Complete -> Base, occurs when Black Hole Detected
pl.pmtu is set to SCTP_BASE_PLPMTU,
probe_size is set back to SCTP_BASE_PLPMTU;
Note a black hole is encountered when a sender is unaware that packets
are not being delivered to the destination endpoint. So it includes the
probe failures with equal probe_size to pl.pmtu, and definitely not
include that with greater probe_size than pl.pmtu. The later one is the
normal probe failure where probe_size should decrease back to pl.pmtu
and pl.probe_high is set. pl.probe_high would be used on HB ACK recv
path in the next patch.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch does exactly what rfc8899#section-6.2.1.2 says:
The SCTP sender needs to be able to determine the total size of a
probe packet. The HEARTBEAT chunk could carry a Heartbeat
Information parameter that includes, besides the information
suggested in [RFC4960], the probe size to help an implementation
associate a HEARTBEAT ACK with the size of probe that was sent. The
sender could also use other methods, such as sending a nonce and
verifying the information returned also contains the corresponding
nonce. The length of the PAD chunk is computed by reducing the
probing size by the size of the SCTP common header and the HEARTBEAT
chunk.
Note that HB ACK chunk will carry back whatever HB chunk carried, including
the probe_size we put it in; We also check hbinfo->probe_size in the HB ACK
against link->pl.probe_size to validate this HB ACK chunk.
v1->v2:
- Remove the unused 'sp' and add static for sctp_packet_bundle_pad().
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are 3 timers described in rfc8899#section-5.1.1:
PROBE_TIMER, PMTU_RAISE_TIMER, CONFIRMATION_TIMER
This patches adds a 'probe_timer' in transport, and it works as either
PROBE_TIMER or PMTU_RAISE_TIMER. At most time, it works as PROBE_TIMER
and expires every a 'probe_interval' time to send the HB probe packet.
When transport pl enters COMPLETE state, it works as PMTU_RAISE_TIMER
and expires in 'probe_interval * 30' time to go back to SEARCH state
and do searching again.
SCTP HB is an acknowledged packet, CONFIRMATION_TIMER is not needed.
The timer will start when transport pl enters BASE state and stop
when it enters DISABLED state.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
These are 4 constants described in rfc8899#section-5.1.2:
MAX_PROBES, MIN_PLPMTU, MAX_PLPMTU, BASE_PLPMTU;
And 2 variables described in rfc8899#section-5.1.3:
PROBED_SIZE, PROBE_COUNT;
And 5 states described in rfc8899#section-5.2:
DISABLED, BASE, SEARCH, SEARCH_COMPLETE, ERROR;
And these 4 APIs are used to reset/update PLPMTUD, check if PLPMTUD is
enabled, and calculate the additional headers length for a transport.
Note the member 'probe_high' in transport will be set to the probe
size when a probe fails with this probe size in the next patches.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
PLPMTUD can be enabled by doing 'sysctl -w net.sctp.probe_interval=n'.
'n' is the interval for PLPMTUD probe timer in milliseconds, and it
can't be less than 5000 if it's not 0.
All asoc/transport's PLPMTUD in a new socket will be enabled by default.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This chunk is defined in rfc4820#section-3, and used to pad an
SCTP packet. The receiver must discard this chunk and continue
processing the rest of the chunks in the packet.
Add it now, as it will be bundled with a heartbeat chunk to probe
pmtu in the following patches.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
