-
Junwei Hu authored
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: a62fbcce ("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>
7e27e8d6