linux-stable/net
Paolo Abeni 44ee4764c6 mptcp: fix possible NULL pointer dereference on close
[ Upstream commit d109a77672 ]

After the blamed commit below, the MPTCP release callback can
dereference the first subflow pointer via __mptcp_set_connected()
and send buffer auto-tuning. Such pointer is always expected to be
valid, except at socket destruction time, when the first subflow is
deleted and the pointer zeroed.

If the connect event is handled by the release callback while the
msk socket is finally released, MPTCP hits the following splat:

  general protection fault, probably for non-canonical address 0xdffffc00000000f2: 0000 [#1] PREEMPT SMP KASAN
  KASAN: null-ptr-deref in range [0x0000000000000790-0x0000000000000797]
  CPU: 1 PID: 26719 Comm: syz-executor.2 Not tainted 6.6.0-syzkaller-10102-gff269e2cd5ad #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
  RIP: 0010:mptcp_subflow_ctx net/mptcp/protocol.h:542 [inline]
  RIP: 0010:__mptcp_propagate_sndbuf net/mptcp/protocol.h:813 [inline]
  RIP: 0010:__mptcp_set_connected+0x57/0x3e0 net/mptcp/subflow.c:424
  RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff8a62323c
  RDX: 00000000000000f2 RSI: ffffffff8a630116 RDI: 0000000000000790
  RBP: ffff88803334b100 R08: 0000000000000001 R09: 0000000000000000
  R10: 0000000000000001 R11: 0000000000000034 R12: ffff88803334b198
  R13: ffff888054f0b018 R14: 0000000000000000 R15: ffff88803334b100
  FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007fbcb4f75198 CR3: 000000006afb5000 CR4: 00000000003506f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   mptcp_release_cb+0xa2c/0xc40 net/mptcp/protocol.c:3405
   release_sock+0xba/0x1f0 net/core/sock.c:3537
   mptcp_close+0x32/0xf0 net/mptcp/protocol.c:3084
   inet_release+0x132/0x270 net/ipv4/af_inet.c:433
   inet6_release+0x4f/0x70 net/ipv6/af_inet6.c:485
   __sock_release+0xae/0x260 net/socket.c:659
   sock_close+0x1c/0x20 net/socket.c:1419
   __fput+0x270/0xbb0 fs/file_table.c:394
   task_work_run+0x14d/0x240 kernel/task_work.c:180
   exit_task_work include/linux/task_work.h:38 [inline]
   do_exit+0xa92/0x2a20 kernel/exit.c:876
   do_group_exit+0xd4/0x2a0 kernel/exit.c:1026
   get_signal+0x23ba/0x2790 kernel/signal.c:2900
   arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309
   exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
   exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
   __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
   syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296
   do_syscall_64+0x4b/0x110 arch/x86/entry/common.c:88
   entry_SYSCALL_64_after_hwframe+0x63/0x6b
  RIP: 0033:0x7fb515e7cae9
  Code: Unable to access opcode bytes at 0x7fb515e7cabf.
  RSP: 002b:00007fb516c560c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
  RAX: 000000000000003c RBX: 00007fb515f9c120 RCX: 00007fb515e7cae9
  RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000006
  RBP: 00007fb515ec847a R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
  R13: 000000000000006e R14: 00007fb515f9c120 R15: 00007ffc631eb968
   </TASK>

To avoid sparkling unneeded conditionals, address the issue explicitly
checking msk->first only in the critical place.

Fixes: 8005184fd1 ("mptcp: refactor sndbuf auto-tuning")
Cc: stable@vger.kernel.org
Reported-by: <syzbot+9dfbaedb6e6baca57a32@syzkaller.appspotmail.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/454
Reported-by: Eric Dumazet <edumazet@google.com>
Closes: https://lore.kernel.org/netdev/CANn89iLZUA6S2a=K8GObnS62KK6Jt4B7PsAs7meMFooM8xaTgw@mail.gmail.com/
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20231114-upstream-net-20231113-mptcp-misc-fixes-6-7-rc2-v1-2-7b9cd6a7b7f4@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 4fd19a3070 ("mptcp: fix inconsistent state on fastopen race")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-05 15:19:41 +01:00
..
6lowpan
9p net: 9p: avoid freeing uninit memory in p9pdu_vreadf 2024-01-01 12:42:41 +00:00
802
8021q net: check vlan filter feature in vlan_vids_add_by_dev() and vlan_vids_del_by_dev() 2024-01-01 12:42:32 +00:00
appletalk appletalk: Fix Use-After-Free in atalk_ioctl 2023-12-20 17:01:50 +01:00
atm atm: Fix Use-After-Free in do_vcc_ioctl 2023-12-20 17:01:48 +01:00
ax25 ax25: Kconfig: Update link for linux-ax25.org 2023-09-18 12:56:58 +01:00
batman-adv Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-08-24 10:51:39 -07:00
bluetooth Bluetooth: Add more enc key size check 2024-01-01 12:42:41 +00:00
bpf bpf: Prevent inlining of bpf_fentry_test7() 2023-08-30 08:36:17 +02:00
bpfilter
bridge netfilter: nf_conntrack_bridge: initialize err to 0 2023-11-28 17:19:52 +00:00
caif
can can: isotp: isotp_sendmsg(): fix TX state detection and wait behavior 2023-10-06 12:54:33 +02:00
ceph libceph: use kernel_connect() 2023-10-09 13:35:24 +02:00
core net: avoid build bug in skb extension length calculation 2024-01-01 12:42:42 +00:00
dcb
dccp dccp/tcp: Call security_inet_conn_request() after setting IPv6 addresses. 2023-11-20 11:59:35 +01:00
devlink devlink: Hold devlink lock on health reporter dump get 2023-10-06 15:56:46 -07:00
dns_resolver keys, dns: Allow key types (eg. DNS) to be reclaimed immediately on expiry 2024-01-01 12:42:33 +00:00
dsa
ethernet
ethtool ethtool: don't propagate EOPNOTSUPP from dumps 2023-12-08 08:52:23 +01:00
handshake net/handshake: fix file ref count in handshake_nl_accept_doit() 2023-10-23 10:19:33 -07:00
hsr hsr: Prevent use after free in prp_create_tagged_frame() 2023-11-20 11:59:34 +01:00
ieee802154 sysctl-6.6-rc1 2023-08-29 17:39:15 -07:00
ife net: sched: ife: fix potential use-after-free 2024-01-01 12:42:30 +00:00
ipv4 net: Remove acked SYN flag from packet in the transmit queue correctly 2023-12-20 17:01:49 +01:00
ipv6 net/ipv6: Revert remove expired routes with a separated list of routes 2024-01-01 12:42:33 +00:00
iucv
kcm kcm: Fix error handling for SOCK_DGRAM in kcm_sendmsg(). 2023-09-14 10:43:51 +02:00
key Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-08-18 12:44:56 -07:00
l2tp udp: annotate data-races around udp->encap_type 2023-11-20 11:58:56 +01:00
l3mdev
lapb
llc llc: verify mac len before reading mac header 2023-11-20 11:59:34 +01:00
mac80211 wifi: mac80211: mesh_plink: fix matches_local logic 2024-01-01 12:42:27 +00:00
mac802154
mctp mctp: perform route lookups under a RCU read-side lock 2023-10-10 19:43:22 -07:00
mpls
mptcp mptcp: fix possible NULL pointer dereference on close 2024-01-05 15:19:41 +01:00
ncsi Revert ncsi: Propagate carrier gain/loss events to the NCSI controller 2023-11-28 17:20:10 +00:00
netfilter netfilter: nft_set_pipapo: skip inactive elements during set walk 2023-12-13 18:45:35 +01:00
netlabel
netlink drop_monitor: Require 'CAP_SYS_ADMIN' when joining "events" group 2023-12-13 18:45:10 +01:00
netrom netrom: Deny concurrent connect(). 2023-08-28 06:58:46 +01:00
nfc nfc: nci: fix possible NULL pointer dereference in send_acknowledge() 2023-10-16 17:34:53 -07:00
nsh
openvswitch net/sched: act_ct: Always fill offloading tuple iifidx 2023-11-20 11:59:37 +01:00
packet packet: Move reference count in packet_sock to atomic_long_t 2023-12-13 18:45:23 +01:00
phonet
psample psample: Require 'CAP_NET_ADMIN' when joining "packets" group 2023-12-13 18:45:10 +01:00
qrtr
rds net: prevent address rewrite in kernel_bind() 2023-10-01 19:31:29 +01:00
rfkill net: rfkill: gpio: set GPIO direction 2024-01-01 12:42:41 +00:00
rose net/rose: fix races in rose_kill_by_device() 2024-01-01 12:42:31 +00:00
rxrpc rxrpc: Fix some minor issues with bundle tracing 2023-12-20 17:01:55 +01:00
sched net/sched: act_ct: Take per-cb reference to tcf_ct_flow_table 2023-12-20 17:01:47 +01:00
sctp sctp: update hb timer immediately after users change hb_interval 2023-10-04 17:29:58 -07:00
smc net/smc: fix missing byte order conversion in CLC handshake 2023-12-13 18:45:11 +01:00
strparser
sunrpc SUNRPC: Revert 5f7fc5d69f 2024-01-01 12:42:26 +00:00
switchdev
tipc tipc: Fix kernel-infoleak due to uninitialized TLV value 2023-11-28 17:19:51 +00:00
tls net: tls, update curr on splice as well 2023-12-13 18:45:10 +01:00
unix bpf, sockmap: af_unix stream sockets need to hold ref for pair sock 2023-12-08 08:52:23 +01:00
vmw_vsock vsock/virtio: Fix unsigned integer wrap around in virtio_transport_has_space() 2023-12-20 17:01:50 +01:00
wireless wifi: cfg80211: fix certs build to not depend on file order 2024-01-01 12:42:39 +00:00
x25
xdp xsk: Skip polling event check for unbound socket 2023-12-13 18:45:06 +01:00
xfrm ipsec-2023-10-17 2023-10-17 18:21:13 -07:00
compat.c
devres.c
Kconfig
Kconfig.debug
Makefile
socket.c net: prevent address rewrite in kernel_bind() 2023-10-01 19:31:29 +01:00
sysctl_net.c