[ Upstream commit a80c9d945a ]
A null-ptr-deref was reported in the SCTP transmit path when SCTP-AUTH key
initialization fails:
==================================================================
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 0 PID: 16 Comm: ksoftirqd/0 Tainted: G W 6.6.0 #2
RIP: 0010:sctp_packet_bundle_auth net/sctp/output.c:264 [inline]
RIP: 0010:sctp_packet_append_chunk+0xb36/0x1260 net/sctp/output.c:401
Call Trace:
sctp_packet_transmit_chunk+0x31/0x250 net/sctp/output.c:189
sctp_outq_flush_data+0xa29/0x26d0 net/sctp/outqueue.c:1111
sctp_outq_flush+0xc80/0x1240 net/sctp/outqueue.c:1217
sctp_cmd_interpreter.isra.0+0x19a5/0x62c0 net/sctp/sm_sideeffect.c:1787
sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline]
sctp_do_sm+0x1a3/0x670 net/sctp/sm_sideeffect.c:1169
sctp_assoc_bh_rcv+0x33e/0x640 net/sctp/associola.c:1052
sctp_inq_push+0x1dd/0x280 net/sctp/inqueue.c:88
sctp_rcv+0x11ae/0x3100 net/sctp/input.c:243
sctp6_rcv+0x3d/0x60 net/sctp/ipv6.c:1127
The issue is triggered when sctp_auth_asoc_init_active_key() fails in
sctp_sf_do_5_1C_ack() while processing an INIT_ACK. In this case, the
command sequence is currently:
- SCTP_CMD_PEER_INIT
- SCTP_CMD_TIMER_STOP (T1_INIT)
- SCTP_CMD_TIMER_START (T1_COOKIE)
- SCTP_CMD_NEW_STATE (COOKIE_ECHOED)
- SCTP_CMD_ASSOC_SHKEY
- SCTP_CMD_GEN_COOKIE_ECHO
If SCTP_CMD_ASSOC_SHKEY fails, asoc->shkey remains NULL, while
asoc->peer.auth_capable and asoc->peer.peer_chunks have already been set by
SCTP_CMD_PEER_INIT. This allows a DATA chunk with auth = 1 and shkey = NULL
to be queued by sctp_datamsg_from_user().
Since command interpretation stops on failure, no COOKIE_ECHO should been
sent via SCTP_CMD_GEN_COOKIE_ECHO. However, the T1_COOKIE timer has already
been started, and it may enqueue a COOKIE_ECHO into the outqueue later. As
a result, the DATA chunk can be transmitted together with the COOKIE_ECHO
in sctp_outq_flush_data(), leading to the observed issue.
Similar to the other places where it calls sctp_auth_asoc_init_active_key()
right after sctp_process_init(), this patch moves the SCTP_CMD_ASSOC_SHKEY
immediately after SCTP_CMD_PEER_INIT, before stopping T1_INIT and starting
T1_COOKIE. This ensures that if shared key generation fails, authenticated
DATA cannot be sent. It also allows the T1_INIT timer to retransmit INIT,
giving the client another chance to process INIT_ACK and retry key setup.
Fixes: 730fc3d05c ("[SCTP]: Implete SCTP-AUTH parameter processing")
Reported-by: Zhen Chen <chenzhen126@huawei.com>
Tested-by: Zhen Chen <chenzhen126@huawei.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/44881224b375aa8853f5e19b4055a1a56d895813.1768324226.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 622e8838a2 ]
SCTP_DBG_OBJCNT_INC() is called only when sctp_init_sock()
returns 0 after successfully allocating sctp_sk(sk)->ep.
OTOH, SCTP_DBG_OBJCNT_DEC() is called in sctp_close().
The code seems to expect that the socket is always exposed
to userspace once SCTP_DBG_OBJCNT_INC() is incremented, but
there is a path where the assumption is not true.
In sctp_accept(), sctp_sock_migrate() could fail after
sctp_init_sock().
Then, sk_common_release() does not call inet_release() nor
sctp_close(). Instead, it calls sk->sk_prot->destroy().
Let's move SCTP_DBG_OBJCNT_DEC() from sctp_close() to
sctp_destroy_sock().
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20251023231751.4168390-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1534ff7775 ]
syzbot reported a possible shift-out-of-bounds [1]
Blamed commit added rto_alpha_max and rto_beta_max set to 1000.
It is unclear if some sctp users are setting very large rto_alpha
and/or rto_beta.
In order to prevent user regression, perform the test at run time.
Also add READ_ONCE() annotations as sysctl values can change under us.
[1]
UBSAN: shift-out-of-bounds in net/sctp/transport.c:509:41
shift exponent 64 is too large for 32-bit type 'unsigned int'
CPU: 0 UID: 0 PID: 16704 Comm: syz.2.2320 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120
ubsan_epilogue lib/ubsan.c:233 [inline]
__ubsan_handle_shift_out_of_bounds+0x27f/0x420 lib/ubsan.c:494
sctp_transport_update_rto.cold+0x1c/0x34b net/sctp/transport.c:509
sctp_check_transmitted+0x11c4/0x1c30 net/sctp/outqueue.c:1502
sctp_outq_sack+0x4ef/0x1b20 net/sctp/outqueue.c:1338
sctp_cmd_process_sack net/sctp/sm_sideeffect.c:840 [inline]
sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1372 [inline]
Fixes: b58537a1f5 ("net: sctp: fix permissions for rto_alpha and rto_beta knobs")
Reported-by: syzbot+f8c46c8b2b7f6e076e99@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/690c81ae.050a0220.3d0d33.014e.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20251106111054.3288127-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit af295892a7 ]
Function __sctp_write_space() doesn't set poll key, which leads to
ep_poll_callback() waking up all waiters, not only these waiting
for the socket being writable. Set the key properly using
wake_up_interruptible_poll(), which is preferred over the sync
variant, as writers are not woken up before at least half of the
queue is available. Also, TCP does the same.
Signed-off-by: Petr Malat <oss@malat.biz>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20250516081727.1361451-1-oss@malat.biz
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit f1a69a940d upstream.
sctp_sendmsg() re-uses associations and transports when possible by
doing a lookup based on the socket endpoint and the message destination
address, and then sctp_sendmsg_to_asoc() sets the selected transport in
all the message chunks to be sent.
There's a possible race condition if another thread triggers the removal
of that selected transport, for instance, by explicitly unbinding an
address with setsockopt(SCTP_SOCKOPT_BINDX_REM), after the chunks have
been set up and before the message is sent. This can happen if the send
buffer is full, during the period when the sender thread temporarily
releases the socket lock in sctp_wait_for_sndbuf().
This causes the access to the transport data in
sctp_outq_select_transport(), when the association outqueue is flushed,
to result in a use-after-free read.
This change avoids this scenario by having sctp_transport_free() signal
the freeing of the transport, tagging it as "dead". In order to do this,
the patch restores the "dead" bit in struct sctp_transport, which was
removed in
commit 47faa1e4c5 ("sctp: remove the dead field of sctp_transport").
Then, in the scenario where the sender thread has released the socket
lock in sctp_wait_for_sndbuf(), the bit is checked again after
re-acquiring the socket lock to detect the deletion. This is done while
holding a reference to the transport to prevent it from being freed in
the process.
If the transport was deleted while the socket lock was relinquished,
sctp_sendmsg_to_asoc() will return -EAGAIN to let userspace retry the
send.
The bug was found by a private syzbot instance (see the error report [1]
and the C reproducer that triggers it [2]).
Link: https://people.igalia.com/rcn/kernel_logs/20250402__KASAN_slab-use-after-free_Read_in_sctp_outq_select_transport.txt [1]
Link: https://people.igalia.com/rcn/kernel_logs/20250402__KASAN_slab-use-after-free_Read_in_sctp_outq_select_transport__repro.c [2]
Cc: stable@vger.kernel.org
Fixes: df132eff46 ("sctp: clear the transport of some out_chunk_list chunks in sctp_assoc_rm_peer")
Suggested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Ricardo Cañuelo Navarro <rcn@igalia.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20250404-kasan_slab-use-after-free_read_in_sctp_outq_select_transport__20250404-v1-1-5ce4a0b78ef2@igalia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 606572eb22 ]
According to the C11 standard (ISO/IEC 9899:2011, 6.5.7):
"If E1 has a signed type and E1 x 2^E2 is not representable in the result
type, the behavior is undefined."
Shifting 1 << 31 causes signed integer overflow, which leads to undefined
behavior.
Fix this by explicitly using '1U << 31' to ensure the shift operates on
an unsigned type, avoiding undefined behavior.
Signed-off-by: Yu-Chun Lin <eleanor15x@gmail.com>
Link: https://patch.msgid.link/20250218081217.3468369-1-eleanor15x@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 6259d2484d upstream.
As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:
- Inconsistency: getting info from the reader's/writer's netns vs only
from the opener's netns.
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
(null-ptr-deref), e.g. when the current task is exiting, as spotted by
syzbot [1] using acct(2).
The 'net' structure can be obtained from the table->data using
container_of().
Note that table->data could also be used directly, as this is the only
member needed from the 'net' structure, but that would increase the size
of this fix, to use '*data' everywhere 'net->sctp.probe_interval' is
used.
Fixes: d1e462a7a5 ("sctp: add probe_interval in sysctl and sock/asoc/transport")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/67769ecb.050a0220.3a8527.003f.GAE@google.com [1]
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20250108-net-sysctl-current-nsproxy-v1-8-5df34b2083e8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c10377bbc1 upstream.
As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:
- Inconsistency: getting info from the reader's/writer's netns vs only
from the opener's netns.
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
(null-ptr-deref), e.g. when the current task is exiting, as spotted by
syzbot [1] using acct(2).
The 'net' structure can be obtained from the table->data using
container_of().
Note that table->data could also be used directly, but that would
increase the size of this fix, while 'sctp.ctl_sock' still needs to be
retrieved from 'net' structure.
Fixes: 046c052b47 ("sctp: enable udp tunneling socks")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/67769ecb.050a0220.3a8527.003f.GAE@google.com [1]
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20250108-net-sysctl-current-nsproxy-v1-7-5df34b2083e8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 15649fd541 upstream.
As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:
- Inconsistency: getting info from the reader's/writer's netns vs only
from the opener's netns.
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
(null-ptr-deref), e.g. when the current task is exiting, as spotted by
syzbot [1] using acct(2).
The 'net' structure can be obtained from the table->data using
container_of().
Note that table->data could also be used directly, but that would
increase the size of this fix, while 'sctp.ctl_sock' still needs to be
retrieved from 'net' structure.
Fixes: b14878ccb7 ("net: sctp: cache auth_enable per endpoint")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/67769ecb.050a0220.3a8527.003f.GAE@google.com [1]
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20250108-net-sysctl-current-nsproxy-v1-6-5df34b2083e8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9fc17b76fc upstream.
As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:
- Inconsistency: getting info from the reader's/writer's netns vs only
from the opener's netns.
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
(null-ptr-deref), e.g. when the current task is exiting, as spotted by
syzbot [1] using acct(2).
The 'net' structure can be obtained from the table->data using
container_of().
Note that table->data could also be used directly, as this is the only
member needed from the 'net' structure, but that would increase the size
of this fix, to use '*data' everywhere 'net->sctp.rto_min/max' is used.
Fixes: 4f3fdf3bc5 ("sctp: add check rto_min and rto_max in sysctl")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/67769ecb.050a0220.3a8527.003f.GAE@google.com [1]
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20250108-net-sysctl-current-nsproxy-v1-5-5df34b2083e8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ea62dd1383 upstream.
As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:
- Inconsistency: getting info from the reader's/writer's netns vs only
from the opener's netns.
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
(null-ptr-deref), e.g. when the current task is exiting, as spotted by
syzbot [1] using acct(2).
The 'net' structure can be obtained from the table->data using
container_of().
Note that table->data could also be used directly, as this is the only
member needed from the 'net' structure, but that would increase the size
of this fix, to use '*data' everywhere 'net->sctp.sctp_hmac_alg' is
used.
Fixes: 3c68198e75 ("sctp: Make hmac algorithm selection for cookie generation dynamic")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/67769ecb.050a0220.3a8527.003f.GAE@google.com [1]
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20250108-net-sysctl-current-nsproxy-v1-4-5df34b2083e8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A size validation fix similar to that in Commit 50619dbf8d ("sctp: add
size validation when walking chunks") is also required in sctp_sf_ootb()
to address a crash reported by syzbot:
BUG: KMSAN: uninit-value in sctp_sf_ootb+0x7f5/0xce0 net/sctp/sm_statefuns.c:3712
sctp_sf_ootb+0x7f5/0xce0 net/sctp/sm_statefuns.c:3712
sctp_do_sm+0x181/0x93d0 net/sctp/sm_sideeffect.c:1166
sctp_endpoint_bh_rcv+0xc38/0xf90 net/sctp/endpointola.c:407
sctp_inq_push+0x2ef/0x380 net/sctp/inqueue.c:88
sctp_rcv+0x3831/0x3b20 net/sctp/input.c:243
sctp4_rcv+0x42/0x50 net/sctp/protocol.c:1159
ip_protocol_deliver_rcu+0xb51/0x13d0 net/ipv4/ip_input.c:205
ip_local_deliver_finish+0x336/0x500 net/ipv4/ip_input.c:233
Reported-by: syzbot+f0cbb34d39392f2746ca@syzkaller.appspotmail.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/a29ebb6d8b9f8affd0f9abb296faafafe10c17d8.1730223981.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If hashing fails in sctp_listen_start(), the socket remains in the
LISTENING state, even though it was not added to the hash table.
This can lead to a scenario where a socket appears to be listening
without actually being accessible.
This patch ensures that if the hashing operation fails, the sk_state
is set back to CLOSED before returning an error.
Note that there is no need to undo the autobind operation if hashing
fails, as the bind port can still be used for next listen() call on
the same socket.
Fixes: 76c6d988ae ("sctp: add sock_reuseport for the sock in __sctp_hash_endpoint")
Reported-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
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>
In sctp_listen_start() invoked by sctp_inet_listen(), it should set the
sk_state back to CLOSED if sctp_autobind() fails due to whatever reason.
Otherwise, next time when calling sctp_inet_listen(), if sctp_sk(sk)->reuse
is already set via setsockopt(SCTP_REUSE_PORT), sctp_sk(sk)->bind_hash will
be dereferenced as sk_state is LISTENING, which causes a crash as bind_hash
is NULL.
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:sctp_inet_listen+0x7f0/0xa20 net/sctp/socket.c:8617
Call Trace:
<TASK>
__sys_listen_socket net/socket.c:1883 [inline]
__sys_listen+0x1b7/0x230 net/socket.c:1894
__do_sys_listen net/socket.c:1902 [inline]
Fixes: 5e8f3f703a ("sctp: simplify sctp listening code")
Reported-by: syzbot+f4e0f821e3a3b7cee51d@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Link: https://patch.msgid.link/a93e655b3c153dc8945d7a812e6d8ab0d52b7aa0.1727729391.git.lucien.xin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Unmask the upper DSCP bits when calling ip_route_output_key() so that in
the future it could perform the FIB lookup according to the full DSCP
value.
Note that the 'tos' variable holds the full DS field.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sctp_sf_do_5_2_4_dupcook() currently calls security_sctp_assoc_request()
on new_asoc, but as it turns out, this association is always discarded
and the LSM labels never get into the final association (asoc).
This can be reproduced by having two SCTP endpoints try to initiate an
association with each other at approximately the same time and then peel
off the association into a new socket, which exposes the unitialized
labels and triggers SELinux denials.
Fix it by calling security_sctp_assoc_request() on asoc instead of
new_asoc. Xin Long also suggested limit calling the hook only to cases
A, B, and D, since in cases C and E the COOKIE ECHO chunk is discarded
and the association doesn't enter the ESTABLISHED state, so rectify that
as well.
One related caveat with SELinux and peer labeling: When an SCTP
connection is set up simultaneously in this way, we will end up with an
association that is initialized with security_sctp_assoc_request() on
both sides, so the MLS component of the security context of the
association will get swapped between the peers, instead of just one side
setting it to the other's MLS component. However, at that point
security_sctp_assoc_request() had already been called on both sides in
sctp_sf_do_unexpected_init() (on a temporary association) and thus if
the exchange didn't fail before due to MLS, it won't fail now either
(most likely both endpoints have the same MLS range).
Tested by:
- reproducer from https://src.fedoraproject.org/tests/selinux/pull-request/530
- selinux-testsuite (https://github.com/SELinuxProject/selinux-testsuite/)
- sctp-tests (https://github.com/sctp/sctp-tests) - no tests failed
that wouldn't fail also without the patch applied
Fixes: c081d53f97 ("security: pass asoc to sctp_assoc_request and sctp_sk_clone")
Suggested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com> (LSM/SELinux)
Link: https://patch.msgid.link/20240826130711.141271-1-omosnace@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
syzbot reported a null-ptr-deref while accessing sk2->sk_reuseport_cb in
reuseport_add_sock(). [0]
The repro first creates a listener with SO_REUSEPORT. Then, it creates
another listener on the same port and concurrently closes the first
listener.
The second listen() calls reuseport_add_sock() with the first listener as
sk2, where sk2->sk_reuseport_cb is not expected to be cleared concurrently,
but the close() does clear it by reuseport_detach_sock().
The problem is SCTP does not properly synchronise reuseport_alloc(),
reuseport_add_sock(), and reuseport_detach_sock().
The caller of reuseport_alloc() and reuseport_{add,detach}_sock() must
provide synchronisation for sockets that are classified into the same
reuseport group.
Otherwise, such sockets form multiple identical reuseport groups, and
all groups except one would be silently dead.
1. Two sockets call listen() concurrently
2. No socket in the same group found in sctp_ep_hashtable[]
3. Two sockets call reuseport_alloc() and form two reuseport groups
4. Only one group hit first in __sctp_rcv_lookup_endpoint() receives
incoming packets
Also, the reported null-ptr-deref could occur.
TCP/UDP guarantees that would not happen by holding the hash bucket lock.
Let's apply the locking strategy to __sctp_hash_endpoint() and
__sctp_unhash_endpoint().
[0]:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
CPU: 1 UID: 0 PID: 10230 Comm: syz-executor119 Not tainted 6.10.0-syzkaller-12585-g301927d2d2eb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:reuseport_add_sock+0x27e/0x5e0 net/core/sock_reuseport.c:350
Code: 00 0f b7 5d 00 bf 01 00 00 00 89 de e8 1b a4 ff f7 83 fb 01 0f 85 a3 01 00 00 e8 6d a0 ff f7 49 8d 7e 12 48 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 4b 02 00 00 41 0f b7 5e 12 49 8d 7e 14
RSP: 0018:ffffc9000b947c98 EFLAGS: 00010202
RAX: 0000000000000002 RBX: ffff8880252ddf98 RCX: ffff888079478000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000012
RBP: 0000000000000001 R08: ffffffff8993e18d R09: 1ffffffff1fef385
R10: dffffc0000000000 R11: fffffbfff1fef386 R12: ffff8880252ddac0
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f24e45b96c0(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcced5f7b8 CR3: 00000000241be000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__sctp_hash_endpoint net/sctp/input.c:762 [inline]
sctp_hash_endpoint+0x52a/0x600 net/sctp/input.c:790
sctp_listen_start net/sctp/socket.c:8570 [inline]
sctp_inet_listen+0x767/0xa20 net/sctp/socket.c:8625
__sys_listen_socket net/socket.c:1883 [inline]
__sys_listen+0x1b7/0x230 net/socket.c:1894
__do_sys_listen net/socket.c:1902 [inline]
__se_sys_listen net/socket.c:1900 [inline]
__x64_sys_listen+0x5a/0x70 net/socket.c:1900
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f24e46039b9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 91 1a 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f24e45b9228 EFLAGS: 00000246 ORIG_RAX: 0000000000000032
RAX: ffffffffffffffda RBX: 00007f24e468e428 RCX: 00007f24e46039b9
RDX: 00007f24e46039b9 RSI: 0000000000000003 RDI: 0000000000000004
RBP: 00007f24e468e420 R08: 00007f24e45b96c0 R09: 00007f24e45b96c0
R10: 00007f24e45b96c0 R11: 0000000000000246 R12: 00007f24e468e42c
R13: 00007f24e465a5dc R14: 0020000000000001 R15: 00007ffcced5f7d8
</TASK>
Modules linked in:
Fixes: 6ba8457402 ("sctp: process sk_reuseport in sctp_get_port_local")
Reported-by: syzbot+e6979a5d2f10ecb700e4@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=e6979a5d2f10ecb700e4
Tested-by: syzbot+e6979a5d2f10ecb700e4@syzkaller.appspotmail.com
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20240731234624.94055-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
const qualify the struct ctl_table argument in the proc_handler function
signatures. This is a prerequisite to moving the static ctl_table
structs into .rodata data which will ensure that proc_handler function
pointers cannot be modified.
This patch has been generated by the following coccinelle script:
```
virtual patch
@r1@
identifier ctl, write, buffer, lenp, ppos;
identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)";
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int write, void *buffer, size_t *lenp, loff_t *ppos);
@r2@
identifier func, ctl, write, buffer, lenp, ppos;
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int write, void *buffer, size_t *lenp, loff_t *ppos)
{ ... }
@r3@
identifier func;
@@
int func(
- struct ctl_table *
+ const struct ctl_table *
,int , void *, size_t *, loff_t *);
@r4@
identifier func, ctl;
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int , void *, size_t *, loff_t *);
@r5@
identifier func, write, buffer, lenp, ppos;
@@
int func(
- struct ctl_table *
+ const struct ctl_table *
,int write, void *buffer, size_t *lenp, loff_t *ppos);
```
* Code formatting was adjusted in xfs_sysctl.c to comply with code
conventions. The xfs_stats_clear_proc_handler,
xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where
adjusted.
* The ctl_table argument in proc_watchdog_common was const qualified.
This is called from a proc_handler itself and is calling back into
another proc_handler, making it necessary to change it as part of the
proc_handler migration.
Co-developed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Co-developed-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Joel Granados <j.granados@samsung.com>
As David Laight noticed,
"In a multithreaded program it is reasonable to have a thread blocked in
accept(). With TCP a subsequent shutdown(listen_fd, SHUT_RDWR) causes
the accept to fail. But nothing happens for SCTP."
sctp_disconnect() is eventually called when shutdown a listen socket,
but nothing is done in this function. This patch sets RCV_SHUTDOWN
flag in sk->sk_shutdown there, and adds the check (sk->sk_shutdown &
RCV_SHUTDOWN) to break and return in sctp_accept().
Note that shutdown() is only supported on TCP-style SCTP socket.
Reported-by: David Laight <David.Laight@aculab.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rather than pass in flags, error pointer, and whether this is a kernel
invocation or not, add a struct proto_accept_arg struct as the argument.
This then holds all of these arguments, and prepares accept for being
able to pass back more information.
No functional changes in this patch.
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which
will reduce the overall build time size of the kernel and run time
memory bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)
To avoid lots of small commits, this commit brings together network
changes from (as they appear in MAINTAINERS) LLC, MPTCP, NETROM NETWORK
LAYER, PHONET PROTOCOL, ROSE NETWORK LAYER, RXRPC SOCKETS, SCTP
PROTOCOL, SHARED MEMORY COMMUNICATIONS (SMC), TIPC NETWORK LAYER and
NETWORKING [IPSEC]
* Remove sentinel element from ctl_table structs.
* Replace empty array registration with the register_net_sysctl_sz call
in llc_sysctl_init
* Replace the for loop stop condition that tests for procname == NULL
with one that depends on array size in sctp_sysctl_net_register
* Remove instances where an array element is zeroed out to make it look
like a sentinel in xfrm_sysctl_init. This is not longer needed and is
safe after commit c899710fe7 ("networking: Update to
register_net_sysctl_sz") added the array size to the ctl_table
registration
* Use a table_size variable to keep the value of ARRAY_SIZE
Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of (struct rt6_info *)dst casts, we can use :
#define dst_rt6_info(_ptr) \
container_of_const(_ptr, struct rt6_info, dst)
Some places needed missing const qualifiers :
ip6_confirm_neigh(), ipv6_anycast_destination(),
ipv6_unicast_destination(), has_gateway()
v2: added missing parts (David Ahern)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
To be able to constify instances of struct ctl_tables it is necessary to
remove ways through which non-const versions are exposed from the
sysctl core.
One of these is the ctl_table_arg member of struct ctl_table_header.
Constify this reference as a prerequisite for the full constification of
struct ctl_table instances.
No functional change.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
While looking at UDP receive performance, I saw sk_wake_async()
was no longer inlined.
This matters at least on AMD Zen1-4 platforms (see SRSO)
This might be because rcu_read_lock() and rcu_read_unlock()
are no longer nops in recent kernels ?
Add sk_wake_async_rcu() variant, which must be called from
contexts already holding rcu lock.
As SOCK_FASYNC is deprecated in modern days, use unlikely()
to give a hint to the compiler.
sk_wake_async_rcu() is properly inlined from
__udp_enqueue_schedule_skb() and sock_def_readable().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240328144032.1864988-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
commit 0a31bd5f2b ("KMEM_CACHE(): simplify slab cache creation")
introduces a new macro.
Use the new KMEM_CACHE() macro instead of direct kmem_cache_create
to simplify the creation of SLAB caches.
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Following patch is going to use RCU instead of
inet_diag_table_mutex acquisition.
This patch is a preparation, no change of behavior yet.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
W=1 builds now warn if module is built without a MODULE_DESCRIPTION().
Add descriptions to all the sock diag modules in one fell swoop.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
During the 4-way handshake, the transport's state is set to ACTIVE in
sctp_process_init() when processing INIT_ACK chunk on client or
COOKIE_ECHO chunk on server.
In the collision scenario below:
192.168.1.2 > 192.168.1.1: sctp (1) [INIT] [init tag: 3922216408]
192.168.1.1 > 192.168.1.2: sctp (1) [INIT] [init tag: 144230885]
192.168.1.2 > 192.168.1.1: sctp (1) [INIT ACK] [init tag: 3922216408]
192.168.1.1 > 192.168.1.2: sctp (1) [COOKIE ECHO]
192.168.1.2 > 192.168.1.1: sctp (1) [COOKIE ACK]
192.168.1.1 > 192.168.1.2: sctp (1) [INIT ACK] [init tag: 3914796021]
when processing COOKIE_ECHO on 192.168.1.2, as it's in COOKIE_WAIT state,
sctp_sf_do_dupcook_b() is called by sctp_sf_do_5_2_4_dupcook() where it
creates a new association and sets its transport to ACTIVE then updates
to the old association in sctp_assoc_update().
However, in sctp_assoc_update(), it will skip the transport update if it
finds a transport with the same ipaddr already existing in the old asoc,
and this causes the old asoc's transport state not to move to ACTIVE
after the handshake.
This means if DATA retransmission happens at this moment, it won't be able
to enter PF state because of the check 'transport->state == SCTP_ACTIVE'
in sctp_do_8_2_transport_strike().
This patch fixes it by updating the transport in sctp_assoc_update() with
sctp_assoc_add_peer() where it updates the transport state if there is
already a transport with the same ipaddr exists in the old asoc.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Link: https://lore.kernel.org/r/fd17356abe49713ded425250cc1ae51e9f5846c6.1696172325.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
