linux/net/rxrpc
Eric Dumazet 1946014ca3 rxrpc: fix a race in rxrpc_exit_net()
Current code can lead to the following race:

CPU0                                                 CPU1

rxrpc_exit_net()
                                                     rxrpc_peer_keepalive_worker()
                                                       if (rxnet->live)

  rxnet->live = false;
  del_timer_sync(&rxnet->peer_keepalive_timer);

                                                             timer_reduce(&rxnet->peer_keepalive_timer, jiffies + delay);

  cancel_work_sync(&rxnet->peer_keepalive_work);

rxrpc_exit_net() exits while peer_keepalive_timer is still armed,
leading to use-after-free.

syzbot report was:

ODEBUG: free active (active state 0) object type: timer_list hint: rxrpc_peer_keepalive_timeout+0x0/0xb0
WARNING: CPU: 0 PID: 3660 at lib/debugobjects.c:505 debug_print_object+0x16e/0x250 lib/debugobjects.c:505
Modules linked in:
CPU: 0 PID: 3660 Comm: kworker/u4:6 Not tainted 5.17.0-syzkaller-13993-g88e6c0207623 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
RIP: 0010:debug_print_object+0x16e/0x250 lib/debugobjects.c:505
Code: ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 af 00 00 00 48 8b 14 dd 00 1c 26 8a 4c 89 ee 48 c7 c7 00 10 26 8a e8 b1 e7 28 05 <0f> 0b 83 05 15 eb c5 09 01 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e c3
RSP: 0018:ffffc9000353fb00 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: ffff888029196140 RSI: ffffffff815efad8 RDI: fffff520006a7f52
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815ea4ae R11: 0000000000000000 R12: ffffffff89ce23e0
R13: ffffffff8a2614e0 R14: ffffffff816628c0 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe1f2908924 CR3: 0000000043720000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __debug_check_no_obj_freed lib/debugobjects.c:992 [inline]
 debug_check_no_obj_freed+0x301/0x420 lib/debugobjects.c:1023
 kfree+0xd6/0x310 mm/slab.c:3809
 ops_free_list.part.0+0x119/0x370 net/core/net_namespace.c:176
 ops_free_list net/core/net_namespace.c:174 [inline]
 cleanup_net+0x591/0xb00 net/core/net_namespace.c:598
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>

Fixes: ace45bec6d ("rxrpc: Fix firewall route keepalive")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Marc Dionne <marc.dionne@auristor.com>
Cc: linux-afs@lists.infradead.org
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-06 13:48:51 +01:00
..
af_rxrpc.c rxrpc: Fix fall-through warnings for Clang 2021-06-04 17:40:04 -05:00
ar-internal.h rxrpc: Fix call timer start racing with call destruction 2022-03-31 12:25:25 +02:00
call_accept.c rxrpc: Fix memory leak in rxrpc_lookup_local 2021-01-28 13:12:14 -08:00
call_event.c rxrpc: Fix call timer start racing with call destruction 2022-03-31 12:25:25 +02:00
call_object.c rxrpc: Fix call timer start racing with call destruction 2022-03-31 12:25:25 +02:00
conn_client.c rxrpc: Fix rxrpc_peer leak in rxrpc_look_up_bundle() 2021-11-29 15:39:40 +00:00
conn_event.c rxrpc: Merge prime_packet_security into init_connection_security 2020-11-23 18:09:30 +00:00
conn_object.c rxrpc: Ask the security class how much space to allow in a packet 2020-11-23 19:53:11 +00:00
conn_service.c rxrpc: Don't retain the server key in the connection 2020-11-23 18:09:29 +00:00
input.c rxrpc: Call state should be read with READ_ONCE() under some circumstances 2021-01-13 10:38:20 -08:00
insecure.c rxrpc: Ask the security class how much space to allow in a packet 2020-11-23 19:53:11 +00:00
Kconfig net: RxRPC: make dependent Kconfig symbols be shown indented 2021-08-18 10:12:11 +01:00
key.c rxrpc: Fix handling of an unsupported token type in rxrpc_read() 2021-01-13 10:38:00 -08:00
local_event.c rxrpc: Fix a typo 2021-06-02 14:01:55 -07:00
local_object.c rxrpc: Fix dependency on IPv6 in udp tunnel config 2021-02-12 16:42:05 -08:00
Makefile rxrpc: Split the server key type (rxrpc_s) into its own file 2020-11-23 18:09:29 +00:00
misc.c rxrpc: Fix the excessive initial retransmission timeout 2020-05-11 16:42:28 +01:00
net_ns.c rxrpc: fix a race in rxrpc_exit_net() 2022-04-06 13:48:51 +01:00
output.c rxrpc: Adjust retransmission backoff 2022-01-22 02:03:24 +00:00
peer_event.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
peer_object.c rxrpc: Fix rxrpc_local leak in rxrpc_lookup_peer() 2021-11-29 15:40:02 +00:00
proc.c rxrpc: Rewrite the client connection manager 2020-09-08 21:11:43 +01:00
protocol.h rxrpc: Improve jumbo packet counting 2019-08-27 09:48:37 +01:00
recvmsg.c afs: Don't truncate iter during data fetch 2021-04-23 10:17:26 +01:00
rtt.c rxrpc: Fix _usecs_to_jiffies() by using usecs_to_jiffies() 2021-09-24 14:18:34 +01:00
rxkad.c rxrpc: rxkad: Remove redundant variable offset 2021-04-27 14:05:06 -07:00
security.c rxrpc: Hand server key parsing off to the security class 2020-11-23 18:09:29 +00:00
sendmsg.c rxrpc: Ask the security class how much space to allow in a packet 2020-11-23 19:53:11 +00:00
server_key.c rxrpc: fix some null-ptr-deref bugs in server_key.c 2022-03-31 15:21:31 +02:00
skbuff.c rxrpc: Use skb_unshare() rather than skb_cow_data() 2019-08-27 10:13:46 +01:00
sysctl.c rxrpc: Rewrite the client connection manager 2020-09-08 21:11:43 +01:00
utils.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36 2019-05-24 17:27:11 +02:00