linux/net
Kuniyuki Iwashima 04d9d1fc42 tcp: Fix refcnt handling in __inet_hash_connect().
syzbot reported a warning in sk_nulls_del_node_init_rcu().

The commit 66b60b0c8c ("dccp/tcp: Unhash sk from ehash for tb2 alloc
failure after check_estalblished().") tried to fix an issue that an
unconnected socket occupies an ehash entry when bhash2 allocation fails.

In such a case, we need to revert changes done by check_established(),
which does not hold refcnt when inserting socket into ehash.

So, to revert the change, we need to __sk_nulls_add_node_rcu() instead
of sk_nulls_add_node_rcu().

Otherwise, sock_put() will cause refcnt underflow and leak the socket.

[0]:
WARNING: CPU: 0 PID: 23948 at include/net/sock.h:799 sk_nulls_del_node_init_rcu+0x166/0x1a0 include/net/sock.h:799
Modules linked in:
CPU: 0 PID: 23948 Comm: syz-executor.2 Not tainted 6.8.0-rc6-syzkaller-00159-gc055fc00c07b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
RIP: 0010:sk_nulls_del_node_init_rcu+0x166/0x1a0 include/net/sock.h:799
Code: e8 7f 71 c6 f7 83 fb 02 7c 25 e8 35 6d c6 f7 4d 85 f6 0f 95 c0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc e8 1b 6d c6 f7 90 <0f> 0b 90 eb b2 e8 10 6d c6 f7 4c 89 e7 be 04 00 00 00 e8 63 e7 d2
RSP: 0018:ffffc900032d7848 EFLAGS: 00010246
RAX: ffffffff89cd0035 RBX: 0000000000000001 RCX: 0000000000040000
RDX: ffffc90004de1000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: 1ffff1100439ac26 R08: ffffffff89ccffe3 R09: 1ffff1100439ac28
R10: dffffc0000000000 R11: ffffed100439ac29 R12: ffff888021cd6140
R13: dffffc0000000000 R14: ffff88802a9bf5c0 R15: ffff888021cd6130
FS:  00007f3b823f16c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3b823f0ff8 CR3: 000000004674a000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __inet_hash_connect+0x140f/0x20b0 net/ipv4/inet_hashtables.c:1139
 dccp_v6_connect+0xcb9/0x1480 net/dccp/ipv6.c:956
 __inet_stream_connect+0x262/0xf30 net/ipv4/af_inet.c:678
 inet_stream_connect+0x65/0xa0 net/ipv4/af_inet.c:749
 __sys_connect_file net/socket.c:2048 [inline]
 __sys_connect+0x2df/0x310 net/socket.c:2065
 __do_sys_connect net/socket.c:2075 [inline]
 __se_sys_connect net/socket.c:2072 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2072
 do_syscall_64+0xf9/0x240
 entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7f3b8167dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007f3b823f10c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00007f3b817abf80 RCX: 00007f3b8167dda9
RDX: 000000000000001c RSI: 0000000020000040 RDI: 0000000000000003
RBP: 00007f3b823f1120 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 000000000000000b R14: 00007f3b817abf80 R15: 00007ffd3beb57b8
 </TASK>

Reported-by: syzbot+12c506c1aae251e70449@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=12c506c1aae251e70449
Fixes: 66b60b0c8c ("dccp/tcp: Unhash sk from ehash for tb2 alloc failure after check_estalblished().")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240308201623.65448-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-03-14 10:57:02 +01:00
..
6lowpan net: fill in MODULE_DESCRIPTION()s for 6LoWPAN 2024-02-09 14:12:01 -08:00
9p net: 9p: avoid freeing uninit memory in p9pdu_vreadf 2023-12-13 05:44:30 +09:00
802
8021q rtnetlink: prepare nla_put_iflink() to run under RCU 2024-02-26 11:46:12 +00:00
appletalk net: remove SOCK_DEBUG leftovers 2023-12-26 20:31:01 +00:00
atm net: fill in MODULE_DESCRIPTION()s for mpoa 2024-02-09 14:12:01 -08:00
ax25
batman-adv This cleanup patchset includes the following patches: 2024-02-02 12:44:16 +00:00
bluetooth Bluetooth: hci_sync: Fix UAF in hci_acl_create_conn_sync 2024-03-08 11:06:14 -05:00
bpf for-netdev 2024-03-11 18:06:04 -07:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-02-29 14:24:56 -08:00
caif net: fill in MODULE_DESCRIPTION()s for CAIF 2024-01-05 08:06:35 -08:00
can linux-can-next-for-6.9-20240220 2024-02-20 15:32:45 +01:00
ceph libceph: init the cursor when preparing sparse read in msgr2 2024-03-06 12:43:01 +01:00
core Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
dcb
dccp net: dccp: Simplify the allocation of slab caches in dccp_ackvec_init 2024-02-02 12:19:26 +00:00
devlink devlink: Fix devlink parallel commands processing 2024-03-13 08:31:40 +00:00
dns_resolver Networking changes for 6.8. 2024-01-11 10:07:29 -08:00
dsa net: dsa: Leverage core stats allocator 2024-03-07 20:37:13 -08:00
ethernet
ethtool ethtool: remove ethtool_eee_use_linkmodes 2024-03-06 20:40:20 -08:00
handshake net/handshake: Fix handshake_req_destroy_test1 2024-02-08 18:32:29 -08:00
hsr Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-02-29 14:24:56 -08:00
ieee802154 Merge tag 'ieee802154-for-net-next-2024-03-07' of git://git.kernel.org/pub/scm/linux/kernel/git/wpan/wpan-next 2024-03-08 20:35:33 -08:00
ife net: sched: ife: fix potential use-after-free 2023-12-15 10:50:18 +00:00
ipv4 tcp: Fix refcnt handling in __inet_hash_connect(). 2024-03-14 10:57:02 +01:00
ipv6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-03-11 20:38:36 -07:00
iucv net/af_iucv: fix virtual vs physical address confusion 2024-02-22 18:28:13 -08:00
kcm net: kcm: fix incorrect parameter validation in the kcm_getsockopt) function 2024-03-11 09:53:22 +00:00
key net: fill in MODULE_DESCRIPTION()s for af_key 2024-02-09 14:12:01 -08:00
l2tp l2tp: fix incorrect parameter validation in the pppol2tp_getsockopt() function 2024-03-11 09:53:22 +00:00
l3mdev
lapb
llc llc: call sock_orphan() at release time 2024-01-30 13:49:09 +01:00
mac80211 wireless-next patches for v6.9 2024-03-08 09:05:49 -08:00
mac802154 mac802154: fix llsec key resources release in mac802154_llsec_key_del 2024-03-06 21:01:26 +01:00
mctp Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-02-29 14:24:56 -08:00
mpls mpls: Do not orphan the skb 2024-03-07 20:42:13 -08:00
mptcp mptcp: annotate a data-race around sysctl_tcp_wmem[0] 2024-03-11 10:37:40 +00:00
ncsi
netfilter Networking changes for 6.9. 2024-03-12 17:44:08 -07:00
netlabel netlabel: remove impossible return value in netlbl_bitmap_walk 2024-02-28 19:37:34 -08:00
netlink net/netlink: Add getsockopt support for NETLINK_LISTEN_ALL_NSID 2024-03-11 15:48:34 -07:00
netrom netrom: Fix data-races around sysctl_net_busy_read 2024-03-07 10:36:58 +01:00
nfc nfc: core: make nfc_class constant 2024-03-05 11:21:18 -08:00
nsh
openvswitch net: openvswitch: limit the number of recursions from action sets 2024-02-09 12:54:38 -08:00
packet net/packet: Add getsockopt support for PACKET_COPY_THRESH 2024-03-11 15:52:05 -07:00
phonet phonet/pep: fix racy skb_queue_empty() use 2024-02-22 09:05:50 +01:00
psample genetlink: Use internal flags for multicast groups 2023-12-29 08:43:59 +00:00
qrtr net: qrtr: ns: Return 0 if server port is not present 2024-01-01 18:41:29 +00:00
rds Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-03-07 10:29:36 -08:00
rfkill Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-12-21 22:17:23 +01:00
rose net/rose: fix races in rose_kill_by_device() 2023-12-15 11:59:53 +00:00
rxrpc rxrpc: Extract useful fields from a received ACK to skb priv data 2024-03-05 23:35:26 +00:00
sched net/sched: taprio: proper TCA_TAPRIO_TC_ENTRY_INDEX check 2024-03-13 08:26:42 +00:00
sctp net: introduce include/net/rps.h 2024-03-07 21:12:43 -08:00
smc net/smc: reduce rtnl pressure in smc_pnet_create_pnetids_list() 2024-03-05 15:49:35 +01:00
strparser
sunrpc svcrdma: Add Write chunk WRs to the RPC's Send WR chain 2024-03-01 09:12:30 -05:00
switchdev net: bridge: switchdev: Skip MDB replays of deferred events on offload 2024-02-16 09:36:37 +00:00
tipc tipc: Cleanup tipc_nl_bearer_add() error paths 2024-02-15 13:18:19 +01:00
tls tls: fix use-after-free on failed backlog decryption 2024-02-29 09:07:16 -08:00
unix Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-02-22 15:29:26 -08:00
vmw_vsock sock_diag: add module pointer to "struct sock_diag_handler" 2024-01-23 15:13:54 +01:00
wireless wireless-next patches for v6.9 2024-03-08 09:05:49 -08:00
x25 net/x25: fix incorrect parameter validation in the x25_getsockopt() function 2024-03-11 09:53:22 +00:00
xdp bpf-next-for-netdev 2024-03-02 20:50:59 -08:00
xfrm ipsec-next-2024-03-06 2024-03-08 10:56:05 +00:00
compat.c file: stop exposing receive_fd_user() 2023-12-12 14:24:14 +01:00
devres.c
Kconfig net: bql: allow the config to be disabled 2024-02-18 10:19:21 +00:00
Kconfig.debug
Makefile af_unix: Remove CONFIG_UNIX_SCM. 2024-01-31 16:41:16 -08:00
socket.c net: remove SLAB_MEM_SPREAD flag usage 2024-02-28 19:29:46 -08:00
sysctl_net.c