aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJunwei Hu2019-05-16 10:51:15 +0800
committerDavid S. Miller2019-05-16 12:25:02 -0700
commit7e27e8d6130c5e88fac9ddec4249f7f2337fe7f8 (patch)
tree79a25be33c426c2ee802da089de94365cd5fde60
parent61fb0d01680771f72cc9d39783fb2c122aaad51e (diff)
tipc: switch order of device registration to fix a crash
When tipc is loaded while many processes try to create a TIPC socket, a crash occurs: PANIC: Unable to handle kernel paging request at virtual address "dfff20000000021d" pc : tipc_sk_create+0x374/0x1180 [tipc] lr : tipc_sk_create+0x374/0x1180 [tipc] Exception class = DABT (current EL), IL = 32 bits Call trace: tipc_sk_create+0x374/0x1180 [tipc] __sock_create+0x1cc/0x408 __sys_socket+0xec/0x1f0 __arm64_sys_socket+0x74/0xa8 ... This is due to race between sock_create and unfinished register_pernet_device. tipc_sk_insert tries to do "net_generic(net, tipc_net_id)". but tipc_net_id is not initialized yet. So switch the order of the two to close the race. This can be reproduced with multiple processes doing socket(AF_TIPC, ...) and one process doing module removal. Fixes: a62fbccecd62 ("tipc: make subscriber server support net namespace") Signed-off-by: Junwei Hu <hujunwei4@huawei.com> Reported-by: Wang Wang <wangwang2@huawei.com> Reviewed-by: Xiaogang Wang <wangxiaogang3@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--net/tipc/core.c14
1 files changed, 7 insertions, 7 deletions
diff --git a/net/tipc/core.c b/net/tipc/core.c
index 27cccd101ef6..ddd2e0f67c07 100644
--- a/net/tipc/core.c
+++ b/net/tipc/core.c
@@ -131,10 +131,6 @@ static int __init tipc_init(void)
if (err)
goto out_netlink_compat;
- err = tipc_socket_init();
- if (err)
- goto out_socket;
-
err = tipc_register_sysctl();
if (err)
goto out_sysctl;
@@ -143,6 +139,10 @@ static int __init tipc_init(void)
if (err)
goto out_pernet;
+ err = tipc_socket_init();
+ if (err)
+ goto out_socket;
+
err = tipc_bearer_setup();
if (err)
goto out_bearer;
@@ -150,12 +150,12 @@ static int __init tipc_init(void)
pr_info("Started in single node mode\n");
return 0;
out_bearer:
+ tipc_socket_stop();
+out_socket:
unregister_pernet_subsys(&tipc_net_ops);
out_pernet:
tipc_unregister_sysctl();
out_sysctl:
- tipc_socket_stop();
-out_socket:
tipc_netlink_compat_stop();
out_netlink_compat:
tipc_netlink_stop();
@@ -167,10 +167,10 @@ out_netlink:
static void __exit tipc_exit(void)
{
tipc_bearer_cleanup();
+ tipc_socket_stop();
unregister_pernet_subsys(&tipc_net_ops);
tipc_netlink_stop();
tipc_netlink_compat_stop();
- tipc_socket_stop();
tipc_unregister_sysctl();
pr_info("Deactivated\n");