linux-yocto/net/tipc
Tung Nguyen dd6cb0a857 tipc: fix NULL pointer dereference in tipc_mon_reinit_self()
[ Upstream commit d63527e109e811ef11abb1c2985048fdb528b4cb ]

syzbot reported:

tipc: Node number set to 1055423674
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 3 UID: 0 PID: 6017 Comm: kworker/3:5 Not tainted 6.15.0-rc1-syzkaller-00246-g900241a5cc15 #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events tipc_net_finalize_work
RIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719
...
RSP: 0018:ffffc9000356fb68 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba
RDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010
RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007
R13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010
FS:  0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 tipc_net_finalize+0x10b/0x180 net/tipc/net.c:140
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
...
RIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719
...
RSP: 0018:ffffc9000356fb68 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba
RDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010
RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007
R13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010
FS:  0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

There is a racing condition between workqueue created when enabling
bearer and another thread created when disabling bearer right after
that as follow:

enabling_bearer                          | disabling_bearer
---------------                          | ----------------
tipc_disc_timeout()                      |
{                                        | bearer_disable()
 ...                                     | {
 schedule_work(&tn->work);               |  tipc_mon_delete()
 ...                                     |  {
}                                        |   ...
                                         |   write_lock_bh(&mon->lock);
                                         |   mon->self = NULL;
                                         |   write_unlock_bh(&mon->lock);
                                         |   ...
                                         |  }
tipc_net_finalize_work()                 | }
{                                        |
 ...                                     |
 tipc_net_finalize()                     |
 {                                       |
  ...                                    |
  tipc_mon_reinit_self()                 |
  {                                      |
   ...                                   |
   write_lock_bh(&mon->lock);            |
   mon->self->addr = tipc_own_addr(net); |
   write_unlock_bh(&mon->lock);          |
   ...                                   |
  }                                      |
  ...                                    |
 }                                       |
 ...                                     |
}                                        |

'mon->self' is set to NULL in disabling_bearer thread and dereferenced
later in enabling_bearer thread.

This commit fixes this issue by validating 'mon->self' before assigning
node address to it.

Reported-by: syzbot+ed60da8d686dc709164c@syzkaller.appspotmail.com
Fixes: 46cb01eeeb ("tipc: update mon's self addr when node addr generated")
Signed-off-by: Tung Nguyen <tung.quang.nguyen@est.tech>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250417074826.578115-1-tung.quang.nguyen@est.tech
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-05-02 07:50:43 +02:00
..
addr.c
addr.h tipc: Remove unused function declarations 2023-08-03 12:51:45 +02:00
bcast.c net: tipc: avoid possible garbage value 2024-10-04 16:28:59 +02:00
bcast.h
bearer.c tipc: guard against string buffer overrun 2024-10-10 11:57:25 +02:00
bearer.h tipc: Remove unused function declarations 2023-08-03 12:51:45 +02:00
core.c tipc: fix use-after-free Read in tipc_named_reinit 2022-06-17 11:39:10 +01:00
core.h minmax: add in_range() macro 2023-08-24 16:20:18 -07:00
crypto.c tipc: re-order conditions in tipc_crypto_key_rcv() 2025-02-17 09:40:09 +01:00
crypto.h
diag.c sock_diag: add module pointer to "struct sock_diag_handler" 2024-12-09 10:32:09 +01:00
discover.c treewide: Convert del_timer*() to timer_shutdown*() 2022-12-25 13:38:09 -08:00
discover.h
eth_media.c
group.c
group.h
ib_media.c
Kconfig
link.c tipc: fix memory leak in tipc_link_xmit 2025-04-25 10:45:06 +02:00
link.h tipc: Remove unused declaration tipc_link_build_bc_sync_msg() 2023-08-09 13:03:14 -07:00
Makefile
monitor.c tipc: fix NULL pointer dereference in tipc_mon_reinit_self() 2025-05-02 07:50:43 +02:00
monitor.h
msg.c tipc: fix UAF in error path 2024-05-17 12:02:32 +02:00
msg.h net: tipc: remove unused static inlines 2022-01-27 13:53:27 +00:00
name_distr.c net/tipc: Remove unused struct distr_queue_item 2022-09-29 18:48:32 -07:00
name_distr.h tipc: Remove unused function declarations 2023-08-03 12:51:45 +02:00
name_table.c tipc: cleanup unused function 2022-06-17 11:43:57 +01:00
name_table.h tipc: cleanup unused function 2022-06-17 11:43:57 +01:00
net.c
net.h tipc: Remove unused function declarations 2023-08-03 12:51:45 +02:00
netlink_compat.c tipc: Fix kernel-infoleak due to uninitialized TLV value 2023-11-28 17:19:51 +00:00
netlink.c tipc: Change nla_policy for bearer-related names to NLA_NUL_STRING 2023-11-20 11:59:34 +01:00
netlink.h
node.c tipc: force a dst refcount before doing decryption 2024-06-27 13:49:07 +02:00
node.h
socket.c genetlink: use attrs from struct genl_info 2023-08-15 15:00:45 -07:00
socket.h
subscr.c
subscr.h
sysctl.c
topsrv.c net/sock: Introduce trace_sk_data_ready() 2023-01-23 11:26:50 +00:00
topsrv.h
trace.c
trace.h
udp_media.c tipc: fix NULL deref in cleanup_bearer() 2024-12-19 18:11:27 +01:00
udp_media.h