linux/net
Kuniyuki Iwashima 4204992fec netrom: Deny concurrent connect().
[ Upstream commit c2f8fd7949 ]

syzkaller reported null-ptr-deref [0] related to AF_NETROM.
This is another self-accept issue from the strace log. [1]

syz-executor creates an AF_NETROM socket and calls connect(), which
is blocked at that time.  Then, sk->sk_state is TCP_SYN_SENT and
sock->state is SS_CONNECTING.

  [pid  5059] socket(AF_NETROM, SOCK_SEQPACKET, 0) = 4
  [pid  5059] connect(4, {sa_family=AF_NETROM, sa_data="..." <unfinished ...>

Another thread calls connect() concurrently, which finally fails
with -EINVAL.  However, the problem here is the socket state is
reset even while the first connect() is blocked.

  [pid  5060] connect(4, NULL, 0 <unfinished ...>
  [pid  5060] <... connect resumed>)      = -1 EINVAL (Invalid argument)

As sk->state is TCP_CLOSE and sock->state is SS_UNCONNECTED, the
following listen() succeeds.  Then, the first connect() looks up
itself as a listener and puts skb into the queue with skb->sk itself.
As a result, the next accept() gets another FD of itself as 3, and
the first connect() finishes.

  [pid  5060] listen(4, 0 <unfinished ...>
  [pid  5060] <... listen resumed>)       = 0
  [pid  5060] accept(4, NULL, NULL <unfinished ...>
  [pid  5060] <... accept resumed>)       = 3
  [pid  5059] <... connect resumed>)      = 0

Then, accept4() is called but blocked, which causes the general protection
fault later.

  [pid  5059] accept4(4, NULL, 0x20000400, SOCK_NONBLOCK <unfinished ...>

After that, another self-accept occurs by accept() and writev().

  [pid  5060] accept(4, NULL, NULL <unfinished ...>
  [pid  5061] writev(3, [{iov_base=...}] <unfinished ...>
  [pid  5061] <... writev resumed>)       = 99
  [pid  5060] <... accept resumed>)       = 6

Finally, the leader thread close()s all FDs.  Since the three FDs
reference the same socket, nr_release() does the cleanup for it
three times, and the remaining accept4() causes the following fault.

  [pid  5058] close(3)                    = 0
  [pid  5058] close(4)                    = 0
  [pid  5058] close(5)                    = -1 EBADF (Bad file descriptor)
  [pid  5058] close(6)                    = 0
  [pid  5058] <... exit_group resumed>)   = ?
  [   83.456055][ T5059] general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN

To avoid the issue, we need to return an error for connect() if
another connect() is in progress, as done in __inet_stream_connect().

[0]:
general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 0 PID: 5059 Comm: syz-executor.0 Not tainted 6.5.0-rc5-syzkaller-00194-gace0ab3a4b54 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
RIP: 0010:__lock_acquire+0x109/0x5de0 kernel/locking/lockdep.c:5012
Code: 45 85 c9 0f 84 cc 0e 00 00 44 8b 05 11 6e 23 0b 45 85 c0 0f 84 be 0d 00 00 48 ba 00 00 00 00 00 fc ff df 4c 89 d1 48 c1 e9 03 <80> 3c 11 00 0f 85 e8 40 00 00 49 81 3a a0 69 48 90 0f 84 96 0d 00
RSP: 0018:ffffc90003d6f9e0 EFLAGS: 00010006
RAX: ffff8880244c8000 RBX: 1ffff920007adf6c RCX: 0000000000000003
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000018
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000018 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f51d519a6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f51d5158d58 CR3: 000000002943f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lock_acquire kernel/locking/lockdep.c:5761 [inline]
 lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162
 prepare_to_wait+0x47/0x380 kernel/sched/wait.c:269
 nr_accept+0x20d/0x650 net/netrom/af_netrom.c:798
 do_accept+0x3a6/0x570 net/socket.c:1872
 __sys_accept4_file net/socket.c:1913 [inline]
 __sys_accept4+0x99/0x120 net/socket.c:1943
 __do_sys_accept4 net/socket.c:1954 [inline]
 __se_sys_accept4 net/socket.c:1951 [inline]
 __x64_sys_accept4+0x96/0x100 net/socket.c:1951
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f51d447cae9
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:00007f51d519a0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000120
RAX: ffffffffffffffda RBX: 00007f51d459bf80 RCX: 00007f51d447cae9
RDX: 0000000020000400 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007f51d44c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000800 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f51d459bf80 R15: 00007ffc25c34e48
 </TASK>

Link: https://syzkaller.appspot.com/text?tag=CrashLog&x=152cdb63a80000 [1]
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot+666c97e4686410e79649@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=666c97e4686410e79649
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-13 09:48:09 +02:00
..
6lowpan 6lowpan: Remove redundant initialisation. 2023-03-29 08:22:52 +01:00
9p 9p: virtio: make sure 'offs' is initialized in zc_request 2023-09-13 09:47:50 +02:00
802
8021q vlan: fix a potential uninit-value in vlan_dev_hard_start_xmit() 2023-05-17 12:55:39 +01:00
appletalk
atm atm: hide unused procfs functions 2023-05-17 21:27:30 -07:00
ax25
batman-adv batman-adv: Hold rtnl lock during MTU update via netlink 2023-08-30 14:52:40 +02:00
bluetooth Bluetooth: hci_conn: fail SCO/ISO via hci_conn_failed if ACL gone early 2023-09-13 09:48:07 +02:00
bpf bpf: add test_run support for netfilter program type 2023-04-21 11:34:50 -07:00
bpfilter
bridge Revert "bridge: Add extack warning when enabling STP in netns." 2023-09-13 09:47:49 +02:00
caif
can can: raw: add missing refcount for memory leak fix 2023-08-30 14:52:42 +02:00
ceph libceph: fix potential hang in ceph_osdc_notify() 2023-08-11 12:14:19 +02:00
core net: annotate data-races around sk->sk_lingertime 2023-09-13 09:48:05 +02:00
dcb net: dcb: choose correct policy to parse DCB_ATTR_BCN 2023-08-11 12:14:16 +02:00
dccp ipv4: fix data-races around inet->inet_id 2023-08-30 14:52:31 +02:00
devlink devlink: add missing unregister linecard notification 2023-08-30 14:52:29 +02:00
dns_resolver
dsa net: dsa: sja1105: always enable the send_meta options 2023-07-19 16:36:48 +02:00
ethernet
ethtool ethtool: Fix uninitialized number of lanes 2023-05-03 09:13:20 +01:00
handshake net/handshake: remove fput() that causes use-after-free 2023-06-14 22:26:37 -07:00
hsr hsr: ratelimit only when errors are printed 2023-03-16 21:11:03 -07:00
ieee802154 ieee802154: Replace strlcpy with strscpy 2023-06-16 22:14:24 +02:00
ife
ipv4 lwt: Check LWTUNNEL_XMIT_CONTINUE strictly 2023-09-13 09:48:05 +02:00
ipv6 lwt: Check LWTUNNEL_XMIT_CONTINUE strictly 2023-09-13 09:48:05 +02:00
iucv net/iucv: Fix size of interrupt data 2023-03-16 17:34:40 -07:00
kcm
key net: af_key: fix sadb_x_filter validation 2023-08-23 17:32:42 +02:00
l2tp net: annotate data-races around sk->sk_mark 2023-08-11 12:14:13 +02:00
l3mdev
lapb
llc llc: Don't drop packet from non-root netns. 2023-07-27 08:57:01 +02:00
mac80211 wifi: mac80211: fix puncturing bitmap handling in CSA 2023-09-13 09:48:06 +02:00
mac802154 Merge tag 'ieee802154-for-net-2023-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/wpan/wpan 2023-06-20 09:32:33 +01:00
mctp
mpls net: move gso declarations and functions to their own files 2023-08-11 12:14:12 +02:00
mptcp mptcp: fix the incorrect judgment for msk->cb_flags 2023-08-16 18:32:25 +02:00
ncsi net/ncsi: change from ndo_set_mac_address to dev_set_mac_address 2023-07-23 13:54:17 +02:00
netfilter netfilter: nf_tables: fix kdoc warnings after gc rework 2023-08-30 14:52:45 +02:00
netlabel netlabel: fix shift wrapping bug in netlbl_catmap_setlong() 2023-06-10 19:54:06 +01:00
netlink netlink: Add __sock_i_ino() for __netlink_diag_dump(). 2023-07-19 16:35:38 +02:00
netrom netrom: Deny concurrent connect(). 2023-09-13 09:48:09 +02:00
nfc net: nfc: Fix use-after-free caused by nfc_llcp_find_local 2023-07-19 16:35:36 +02:00
nsh net: move gso declarations and functions to their own files 2023-08-11 12:14:12 +02:00
openvswitch net: openvswitch: reject negative ifindex 2023-08-23 17:32:47 +02:00
packet net/packet: annotate data-races around tp->status 2023-08-16 18:32:25 +02:00
phonet
psample
qrtr net: qrtr: Fix an uninit variable access bug in qrtr_tx_resume() 2023-04-13 09:35:30 +02:00
rds
rfkill net: rfkill-gpio: Add explicit include for of.h 2023-04-06 20:36:27 +02:00
rose
rxrpc rxrpc: Truncate UTS_RELEASE for rxrpc version 2023-05-30 10:01:06 +02:00
sched net/sched: sch_hfsc: Ensure inner classes have fsc curve 2023-09-13 09:48:08 +02:00
sctp ipv4: fix data-races around inet->inet_id 2023-08-30 14:52:31 +02:00
smc net: annotate data-races around sk->sk_lingertime 2023-09-13 09:48:05 +02:00
strparser
sunrpc xprtrdma: Remap Receive buffers after a reconnect 2023-08-30 14:52:27 +02:00
switchdev
tipc tipc: stop tipc crypto on failure in tipc_node_create 2023-08-03 10:25:54 +02:00
tls net: tls: avoid discarding data on record close 2023-08-16 18:32:27 +02:00
unix af_unix: Fix null-ptr-deref in unix_stream_sendpage(). 2023-08-23 17:32:56 +02:00
vmw_vsock bpf, sockmap: Pass skb ownership through read_skb 2023-05-23 16:09:47 +02:00
wireless wifi: nl80211/cfg80211: add forgotten nla_policy for BSS color attribute 2023-09-13 09:48:06 +02:00
x25
xdp xsk: fix refcount underflow in error path 2023-08-16 18:32:26 +02:00
xfrm xfrm: don't skip free of empty state in acquire policy 2023-08-23 17:32:43 +02:00
compat.c net/compat: Update msg_control_is_user when setting a kernel pointer 2023-04-14 11:09:27 +01:00
devres.c
Kconfig net/handshake: Add Kunit tests for the handshake consumer API 2023-04-19 18:48:48 -07:00
Kconfig.debug
Makefile net/handshake: Create a NETLINK service for handling handshake requests 2023-04-19 18:48:48 -07:00
socket.c net: Avoid address overwrite in kernel_connect 2023-09-13 09:47:56 +02:00
sysctl_net.c