[bug report] forever loop in ksocknal_push()

[Zhen, Liang]

Yes, it is indeed a deadloop, I think we didn¹t catch it because it¹s only
called by an utility command which is probably never tried by anyone.
I have posted a patch for it: http://review.whamcloud.com/10128

Thanks
Liang
 

On 4/28/14, 2:38 AM, "Drokin, Oleg" <oleg.drokin at intel.com> wrote:

>Thanks!
>
>Liang, any comments about this?
>
>On Apr 27, 2014, at 2:26 PM, Dan Carpenter wrote:
>
>> Hello Peng Tao,
>> 
>> The patch d7e09d0397e8: "staging: add Lustre file system client
>> support" from May 2, 2013, leads to the following static checker
>> warning:
>> 
>> 	drivers/staging/lustre/lnet/klnds/socklnd/socklnd.c:1904
>>ksocknal_push()
>> 	info: ignoring unreachable code.
>> 
>> drivers/staging/lustre/lnet/klnds/socklnd/socklnd.c
>>  1904          for (i = 0; i < ksocknal_data.ksnd_peer_hash_size; i++) {
>>                                                                   ^^^
>> Not reached.
>> 
>>  1905                  for (j = 0; ; j++) {
>>                             ^^^^^^^^^^^^
>> This loop is a forever loop.  No break statements or exit conditions. I
>> don't know how to fix this.
>> 
>>  1906           
>>read_lock(&ksocknal_data.ksnd_global_lock);
>>  1907  
>>  1908                          index = 0;
>>  1909                          peer = NULL;
>>  1910  
>>  1911                          list_for_each (tmp,
>>&ksocknal_data.ksnd_peers[i]) {
>>  1912                                  peer = list_entry(tmp,
>>ksock_peer_t,
>>  1913                                                        ksnp_list);
>>  1914  
>>  1915                                  if (!((id.nid == LNET_NID_ANY ||
>>  1916                                         id.nid ==
>>peer->ksnp_id.nid) &&
>>  1917                                        (id.pid == LNET_PID_ANY ||
>>  1918                                         id.pid ==
>>peer->ksnp_id.pid))) {
>>  1919                                          peer = NULL;
>>  1920                                          continue;
>>  1921                                  }
>>  1922  
>>  1923                                  if (index++ == j) {
>>  1924           
>>ksocknal_peer_addref(peer);
>>  1925                                          break;
>>  1926                                  }
>>  1927                          }
>>  1928  
>>  1929           
>>read_unlock(&ksocknal_data.ksnd_global_lock);
>>  1930  
>>  1931                          if (peer != NULL) {
>>  1932                                  rc = 0;
>>  1933                                  ksocknal_push_peer (peer);
>>  1934                                  ksocknal_peer_decref(peer);
>>  1935                          }
>>  1936                  }
>>  1937  
>>  1938          }
>> 
>> regards,
>> dan carpenter
>> 
>