From: Taehee Yoo <ap420073@xxxxxxxxx>
[ Upstream commit 9cf1cd8ee3ee09ef2859017df2058e2f53c5347f ]
In order to set/get/dump, the tipc uses the generic netlink
infrastructure. So, when tipc module is inserted, init function
calls genl_register_family().
After genl_register_family(), set/get/dump commands are immediately
allowed and these callbacks internally use the net_generic.
net_generic is allocated by register_pernet_device() but this
is called after genl_register_family() in the __init function.
So, these callbacks would use un-initialized net_generic.
Test commands:
#SHELL1
while :
do
modprobe tipc
modprobe -rv tipc
done
#SHELL2
while :
do
tipc link list
done
Splat looks like:
[ 59.616322][ T2788] kasan: CONFIG_KASAN_INLINE enabled
[ 59.617234][ T2788] kasan: GPF could be caused by NULL-ptr deref or user memory access
[ 59.618398][ T2788] general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[ 59.619389][ T2788] CPU: 3 PID: 2788 Comm: tipc Not tainted 5.4.0+ #194
[ 59.620231][ T2788] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 59.621428][ T2788] RIP: 0010:tipc_bcast_get_broadcast_mode+0x131/0x310 [tipc]
[ 59.622379][ T2788] Code: c7 c6 ef 8b 38 c0 65 ff 0d 84 83 c9 3f e8 d7 a5 f2 e3 48 8d bb 38 11 00 00 48 b8 00 00 00 00
[ 59.622550][ T2780] NET: Registered protocol family 30
[ 59.624627][ T2788] RSP: 0018:ffff88804b09f578 EFLAGS: 00010202
[ 59.624630][ T2788] RAX: dffffc0000000000 RBX: 0000000000000011 RCX: 000000008bc66907
[ 59.624631][ T2788] RDX: 0000000000000229 RSI: 000000004b3cf4cc RDI: 0000000000001149
[ 59.624633][ T2788] RBP: ffff88804b09f588 R08: 0000000000000003 R09: fffffbfff4fb3df1
[ 59.624635][ T2788] R10: fffffbfff50318f8 R11: ffff888066cadc18 R12: ffffffffa6cc2f40
[ 59.624637][ T2788] R13: 1ffff11009613eba R14: ffff8880662e9328 R15: ffff8880662e9328
[ 59.624639][ T2788] FS: 00007f57d8f7b740(0000) GS:ffff88806cc00000(0000) knlGS:0000000000000000
[ 59.624645][ T2788] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 59.625875][ T2780] tipc: Started in single node mode
[ 59.626128][ T2788] CR2: 00007f57d887a8c0 CR3: 000000004b140002 CR4: 00000000000606e0
[ 59.633991][ T2788] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 59.635195][ T2788] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 59.636478][ T2788] Call Trace:
[ 59.637025][ T2788] tipc_nl_add_bc_link+0x179/0x1470 [tipc]
[ 59.638219][ T2788] ? lock_downgrade+0x6e0/0x6e0
[ 59.638923][ T2788] ? __tipc_nl_add_link+0xf90/0xf90 [tipc]
[ 59.639533][ T2788] ? tipc_nl_node_dump_link+0x318/0xa50 [tipc]
[ 59.640160][ T2788] ? mutex_lock_io_nested+0x1380/0x1380
[ 59.640746][ T2788] tipc_nl_node_dump_link+0x4fd/0xa50 [tipc]
[ 59.641356][ T2788] ? tipc_nl_node_reset_link_stats+0x340/0x340 [tipc]
[ 59.642088][ T2788] ? __skb_ext_del+0x270/0x270
[ 59.642594][ T2788] genl_lock_dumpit+0x85/0xb0
[ 59.643050][ T2788] netlink_dump+0x49c/0xed0
[ 59.643529][ T2788] ? __netlink_sendskb+0xc0/0xc0
[ 59.644044][ T2788] ? __netlink_dump_start+0x190/0x800
[ 59.644617][ T2788] ? __mutex_unlock_slowpath+0xd0/0x670
[ 59.645177][ T2788] __netlink_dump_start+0x5a0/0x800
[ 59.645692][ T2788] genl_rcv_msg+0xa75/0xe90
[ 59.646144][ T2788] ? __lock_acquire+0xdfe/0x3de0
[ 59.646692][ T2788] ? genl_family_rcv_msg_attrs_parse+0x320/0x320
[ 59.647340][ T2788] ? genl_lock_dumpit+0xb0/0xb0
[ 59.647821][ T2788] ? genl_unlock+0x20/0x20
[ 59.648290][ T2788] ? genl_parallel_done+0xe0/0xe0
[ 59.648787][ T2788] ? find_held_lock+0x39/0x1d0
[ 59.649276][ T2788] ? genl_rcv+0x15/0x40
[ 59.649722][ T2788] ? lock_contended+0xcd0/0xcd0
[ 59.650296][ T2788] netlink_rcv_skb+0x121/0x350
[ 59.650828][ T2788] ? genl_family_rcv_msg_attrs_parse+0x320/0x320
[ 59.651491][ T2788] ? netlink_ack+0x940/0x940
[ 59.651953][ T2788] ? lock_acquire+0x164/0x3b0
[ 59.652449][ T2788] genl_rcv+0x24/0x40
[ 59.652841][ T2788] netlink_unicast+0x421/0x600
[ ... ]
Fixes: 7e4369057806 ("tipc: fix a slab object leak")
Fixes: a62fbccecd62 ("tipc: make subscriber server support net namespace")
Signed-off-by: Taehee Yoo <ap420073@xxxxxxxxx>
Acked-by: Jon Maloy <jon.maloy@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/tipc/core.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)
--- a/net/tipc/core.c
+++ b/net/tipc/core.c
@@ -125,14 +125,6 @@ static int __init tipc_init(void)
sysctl_tipc_rmem[1] = RCVBUF_DEF;
sysctl_tipc_rmem[2] = RCVBUF_MAX;
- err = tipc_netlink_start();
- if (err)
- goto out_netlink;
-
- err = tipc_netlink_compat_start();
- if (err)
- goto out_netlink_compat;
-
err = tipc_register_sysctl();
if (err)
goto out_sysctl;
@@ -153,8 +145,21 @@ static int __init tipc_init(void)
if (err)
goto out_bearer;
+ err = tipc_netlink_start();
+ if (err)
+ goto out_netlink;
+
+ err = tipc_netlink_compat_start();
+ if (err)
+ goto out_netlink_compat;
+
pr_info("Started in single node mode\n");
return 0;
+
+out_netlink_compat:
+ tipc_netlink_stop();
+out_netlink:
+ tipc_bearer_cleanup();
out_bearer:
unregister_pernet_device(&tipc_topsrv_net_ops);
out_pernet_topsrv:
@@ -164,22 +169,18 @@ out_socket:
out_pernet:
tipc_unregister_sysctl();
out_sysctl:
- tipc_netlink_compat_stop();
-out_netlink_compat:
- tipc_netlink_stop();
-out_netlink:
pr_err("Unable to start in single node mode\n");
return err;
}
static void __exit tipc_exit(void)
{
+ tipc_netlink_compat_stop();
+ tipc_netlink_stop();
tipc_bearer_cleanup();
unregister_pernet_device(&tipc_topsrv_net_ops);
tipc_socket_stop();
unregister_pernet_device(&tipc_net_ops);
- tipc_netlink_stop();
- tipc_netlink_compat_stop();
tipc_unregister_sysctl();
pr_info("Deactivated\n");
