linux-stable.git/net/sctp, branch linux-5.6.y

sctp: check assoc before SCTP_ADDR_{MADE_PRIM, ADDED} event

2020-06-10T18:22:48+00:00

[ Upstream commit 45ebf73ebcec88a34a778f5feaa0b82b1c76069e ]

Make sure SCTP_ADDR_{MADE_PRIM,ADDED} are sent only for associations
that have been established.

These events are described in rfc6458#section-6.1
SCTP_PEER_ADDR_CHANGE:
This tag indicates that an address that is
part of an existing association has experienced a change of
state (e.g., a failure or return to service of the reachability
of an endpoint via a specific transport address).

Signed-off-by: Jonas Falkevik 
Acked-by: Marcelo Ricardo Leitner 
Reviewed-by: Xin Long 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sctp: Start shutdown on association restart if in SHUTDOWN-SENT state and socket is closed

2020-06-03T06:22:51+00:00

[ Upstream commit d3e8e4c11870413789f029a71e72ae6e971fe678 ]

Commit bdf6fa52f01b ("sctp: handle association restarts when the
socket is closed.") starts shutdown when an association is restarted,
if in SHUTDOWN-PENDING state and the socket is closed. However, the
rationale stated in that commit applies also when in SHUTDOWN-SENT
state - we don't want to move an association to ESTABLISHED state when
the socket has been closed, because that results in an association
that is unreachable from user space.

The problem scenario:

1.  Client crashes and/or restarts.

2.  Server (using one-to-one socket) calls close(). SHUTDOWN is lost.

3.  Client reconnects using the same addresses and ports.

4.  Server's association is restarted. The association and the socket
    move to ESTABLISHED state, even though the server process has
    closed its descriptor.

Also, after step 4 when the server process exits, some resources are
leaked in an attempt to release the underlying inet sock structure in
ESTABLISHED state:

    IPv4: Attempt to release TCP socket in state 1 00000000377288c7

Fix by acting the same way as in SHUTDOWN-PENDING state. That is, if
an association is restarted in SHUTDOWN-SENT state and the socket is
closed, then start shutdown and don't move the association or the
socket to ESTABLISHED state.

Fixes: bdf6fa52f01b ("sctp: handle association restarts when the socket is closed.")
Signed-off-by: Jere Leppänen 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sctp: Don't add the shutdown timer if its already been added

2020-06-03T06:22:50+00:00

[ Upstream commit 20a785aa52c82246055a089e55df9dac47d67da1 ]

This BUG halt was reported a while back, but the patch somehow got
missed:

PID: 2879   TASK: c16adaa0  CPU: 1   COMMAND: "sctpn"
 #0 [f418dd28] crash_kexec at c04a7d8c
 #1 [f418dd7c] oops_end at c0863e02
 #2 [f418dd90] do_invalid_op at c040aaca
 #3 [f418de28] error_code (via invalid_op) at c08631a5
    EAX: f34baac0  EBX: 00000090  ECX: f418deb0  EDX: f5542950  EBP: 00000000
    DS:  007b      ESI: f34ba800  ES:  007b      EDI: f418dea0  GS:  00e0
    CS:  0060      EIP: c046fa5e  ERR: ffffffff  EFLAGS: 00010286
 #4 [f418de5c] add_timer at c046fa5e
 #5 [f418de68] sctp_do_sm at f8db8c77 [sctp]
 #6 [f418df30] sctp_primitive_SHUTDOWN at f8dcc1b5 [sctp]
 #7 [f418df48] inet_shutdown at c080baf9
 #8 [f418df5c] sys_shutdown at c079eedf
 #9 [f418df70] sys_socketcall at c079fe88
    EAX: ffffffda  EBX: 0000000d  ECX: bfceea90  EDX: 0937af98
    DS:  007b      ESI: 0000000c  ES:  007b      EDI: b7150ae4
    SS:  007b      ESP: bfceea7c  EBP: bfceeaa8  GS:  0033
    CS:  0073      EIP: b775c424  ERR: 00000066  EFLAGS: 00000282

It appears that the side effect that starts the shutdown timer was processed
multiple times, which can happen as multiple paths can trigger it.  This of
course leads to the BUG halt in add_timer getting called.

Fix seems pretty straightforward, just check before the timer is added if its
already been started.  If it has mod the timer instead to min(current
expiration, new expiration)

Its been tested but not confirmed to fix the problem, as the issue has only
occured in production environments where test kernels are enjoined from being
installed.  It appears to be a sane fix to me though.  Also, recentely,
Jere found a reproducer posted on list to confirm that this resolves the
issues

Signed-off-by: Neil Horman 
CC: Vlad Yasevich 
CC: "David S. Miller" 
CC: jere.leppanen@nokia.com
CC: marcelo.leitner@gmail.com
CC: netdev@vger.kernel.org
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sctp: Fix bundling of SHUTDOWN with COOKIE-ACK

2020-05-14T05:59:20+00:00

commit 145cb2f7177d94bc54563ed26027e952ee0ae03c upstream.

When we start shutdown in sctp_sf_do_dupcook_a(), we want to bundle
the SHUTDOWN with the COOKIE-ACK to ensure that the peer receives them
at the same time and in the correct order. This bundling was broken by
commit 4ff40b86262b ("sctp: set chunk transport correctly when it's a
new asoc"), which assigns a transport for the COOKIE-ACK, but not for
the SHUTDOWN.

Fix this by passing a reference to the COOKIE-ACK chunk as an argument
to sctp_sf_do_9_2_start_shutdown() and onward to
sctp_make_shutdown(). This way the SHUTDOWN chunk is assigned the same
transport as the COOKIE-ACK chunk, which allows them to be bundled.

In sctp_sf_do_9_2_start_shutdown(), the void *arg parameter was
previously unused. Now that we're taking it into use, it must be a
valid pointer to a chunk, or NULL. There is only one call site where
it's not, in sctp_sf_autoclose_timer_expire(). Fix that too.

Fixes: 4ff40b86262b ("sctp: set chunk transport correctly when it's a new asoc")
Signed-off-by: Jere Leppänen 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller 
Cc: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

sctp: Fix SHUTDOWN CTSN Ack in the peer restart case

2020-05-10T08:32:51+00:00

commit 12dfd78e3a74825e6f0bc8df7ef9f938fbc6bfe3 upstream.

When starting shutdown in sctp_sf_do_dupcook_a(), get the value for
SHUTDOWN Cumulative TSN Ack from the new association, which is
reconstructed from the cookie, instead of the old association, which
the peer doesn't have anymore.

Otherwise the SHUTDOWN is either ignored or replied to with an ABORT
by the peer because CTSN Ack doesn't match the peer's Initial TSN.

Fixes: bdf6fa52f01b ("sctp: handle association restarts when the socket is closed.")
Signed-off-by: Jere Leppänen 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sctp: fix refcount bug in sctp_wfree

2020-04-08T07:11:03+00:00

[ Upstream commit 5c3e82fe159622e46e91458c1a6509c321a62820 ]

We should iterate over the datamsgs to move
all chunks(skbs) to newsk.

The following case cause the bug:
for the trouble SKB, it was in outq->transmitted list

sctp_outq_sack
        sctp_check_transmitted
                SKB was moved to outq->sacked list
        then throw away the sack queue
                SKB was deleted from outq->sacked
(but it was held by datamsg at sctp_datamsg_to_asoc
So, sctp_wfree was not called here)

then migrate happened

        sctp_for_each_tx_datachunk(
        sctp_clear_owner_w);
        sctp_assoc_migrate();
        sctp_for_each_tx_datachunk(
        sctp_set_owner_w);
SKB was not in the outq, and was not changed to newsk

finally

__sctp_outq_teardown
        sctp_chunk_put (for another skb)
                sctp_datamsg_put
                        __kfree_skb(msg->frag_list)
                                sctp_wfree (for SKB)
	SKB->sk was still oldsk (skb->sk != asoc->base.sk).

Reported-and-tested-by: syzbot+cea71eec5d6de256d54d@syzkaller.appspotmail.com
Signed-off-by: Qiujun Huang 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sctp: fix possibly using a bad saddr with a given dst

2020-04-08T07:11:03+00:00

[ Upstream commit 582eea230536a6f104097dd46205822005d5fe3a ]

Under certain circumstances, depending on the order of addresses on the
interfaces, it could be that sctp_v[46]_get_dst() would return a dst
with a mismatched struct flowi.

For example, if when walking through the bind addresses and the first
one is not a match, it saves the dst as a fallback (added in
410f03831c07), but not the flowi. Then if the next one is also not a
match, the previous dst will be returned but with the flowi information
for the 2nd address, which is wrong.

The fix is to use a locally stored flowi that can be used for such
attempts, and copy it to the parameter only in case it is a possible
match, together with the corresponding dst entry.

The patch updates IPv6 code mostly just to be in sync. Even though the issue
is also present there, it fallback is not expected to work with IPv6.

Fixes: 410f03831c07 ("sctp: add routing output fallback")
Reported-by: Jin Meng 
Signed-off-by: Marcelo Ricardo Leitner 
Tested-by: Xin Long 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

inet_diag: return classid for all socket types

2020-03-09T04:57:48+00:00

In commit 1ec17dbd90f8 ("inet_diag: fix reporting cgroup classid and
fallback to priority") croup classid reporting was fixed. But this works
only for TCP sockets because for other socket types icsk parameter can
be NULL and classid code path is skipped. This change moves classid
handling to inet_diag_msg_attrs_fill() function.

Also inet_diag_msg_attrs_size() helper was added and addends in
nlmsg_new() were reordered to save order from inet_sk_diag_fill().

Fixes: 1ec17dbd90f8 ("inet_diag: fix reporting cgroup classid and fallback to priority")
Signed-off-by: Dmitry Yakunin 
Reviewed-by: Konstantin Khlebnikov 
Signed-off-by: David S. Miller

sctp: move the format error check out of __sctp_sf_do_9_1_abort

2020-02-18T05:56:03+00:00

When T2 timer is to be stopped, the asoc should also be deleted,
otherwise, there will be no chance to call sctp_association_free
and the asoc could last in memory forever.

However, in sctp_sf_shutdown_sent_abort(), after adding the cmd
SCTP_CMD_TIMER_STOP for T2 timer, it may return error due to the
format error from __sctp_sf_do_9_1_abort() and miss adding
SCTP_CMD_ASSOC_FAILED where the asoc will be deleted.

This patch is to fix it by moving the format error check out of
__sctp_sf_do_9_1_abort(), and do it before adding the cmd
SCTP_CMD_TIMER_STOP for T2 timer.

Thanks Hangbin for reporting this issue by the fuzz testing.

v1->v2:
  - improve the comment in the code as Marcelo's suggestion.

Fixes: 96ca468b86b0 ("sctp: check invalid value of length parameter in error cause")
Reported-by: Hangbin Liu 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: Xin Long 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-01-09T20:13:43+00:00

The ungrafting from PRIO bug fixes in net, when merged into net-next,
merge cleanly but create a build failure.  The resolution used here is
from Petr Machata.

Signed-off-by: David S. Miller