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author | Junwei Hu <hujunwei4@huawei.com> | 2019-05-16 10:51:15 +0800 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2019-05-16 12:25:02 -0700 |
commit | 7e27e8d6130c5e88fac9ddec4249f7f2337fe7f8 (patch) | |
tree | 79a25be33c426c2ee802da089de94365cd5fde60 /net/tipc | |
parent | 61fb0d01680771f72cc9d39783fb2c122aaad51e (diff) | |
download | linux-7e27e8d6130c5e88fac9ddec4249f7f2337fe7f8.tar.bz2 |
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>
Diffstat (limited to 'net/tipc')
-rw-r--r-- | net/tipc/core.c | 14 |
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"); |