Race condition in /ccache/cc_memory.c

[Hong Ye]

Thanks Jeff. When will MIT issue  a new version of KFW? We are having 
trouble building 1.6 branch.

Hong
Jeffrey Altman wrote:
> The fix for this problem is not in KFW 3.2.2.  
> It was not pulled up to the 1.6 branch until 21 July 2008.
> MIT has not issued a new version of the KFW libraries containing this fix.
>
> Jeffrey Altman
>
>
> Hong Ye wrote:
>   
>> When our application crashed, Call stack of one thread
>>     krb5_32.dll!krb5_mcc_free(_krb5_context * context=0x023d87e0,
>> _krb5_ccache * id=0x023d73e8)  Line 170 + 0x3 bytes    C
>>     krb5_32.dll!krb5_mcc_destroy(_krb5_context * context=0x023d87e0,
>> _krb5_ccache * id=0x023d73e8)  Line 208 + 0xb bytes    C
>>     krb5_32.dll!krb5_cc_destroy(_krb5_context * context=0x023d87e0,
>> _krb5_ccache * cache=0x023d73e8)  Line 56    C
>>
>> Call stack of another thread
>>     krb5_32.dll!k5_os_mutex_lock(k5_os_mutex * m=0x01db3d7c)  Line 653
>> + 0xd bytes    C
>>     krb5_32.dll!k5_mutex_lock_1(k5_mutex_t * m=0x01db3d6c,
>> k5_debug_loc l={...})  Line 733 + 0xc bytes    C
>>     krb5_32.dll!profile_node_iterator(void * * iter_p=0x0124f4fc,
>> profile_node * * ret_node=0x00000000, char * * ret_name=0x00000000,
>> char * * ret_value=0x0124f4f8)  Line 470 + 0x29 bytes    C
>>     krb5_32.dll!profile_get_value(_profile_t * profile=0x0243baa8,
>> const char * * names=0x0124f56c, const char * * ret_value=0x0124f580) 
>> Line 184 + 0x11 bytes    C
>>     krb5_32.dll!profile_get_integer(_profile_t * profile=0x0243baa8,
>> const char * name=0x1c08599c, const char * subname=0x1c085928, const
>> char * subsubname=0x00000000, int def_val=4, int *
>> ret_int=0x0124f5f8)  Line 247 + 0x10 bytes    C
>>     krb5_32.dll!init_common(_krb5_context * * context=0x0124f738,
>> unsigned int secure=0, unsigned int kdc=0)  Line 236    C
>>     krb5_32.dll!krb5_init_context(_krb5_context * *
>> context=0x0124f738)  Line 88 + 0xc bytes    C
>>     gssapi32.dll!krb5_gss_init_context(_krb5_context * *
>> ctxp=0x0124f738)  Line 1002    C
>>     gssapi32.dll!krb5_gss_display_name(unsigned int *
>> minor_status=0x0124f914, gss_name_struct * input_name=0x0243a900,
>> gss_buffer_desc_struct * output_name_buffer=0x0124f8f4,
>> gss_OID_desc_struct * * output_name_type=0x0124f904)  Line 37 + 0x9
>> bytes    C
>>     gssapi32.dll!k5glue_display_name(void * ctx=0x00000000, unsigned
>> int * minor_status=0x0124f914, gss_name_struct *
>> input_name=0x0243a900, gss_buffer_desc_struct *
>> output_name_buffer=0x0124f8f4, gss_OID_desc_struct * *
>> output_name_type=0x0124f904)  Line 564 + 0x11 bytes    C
>>     gssapi32.dll!gssint_display_internal_name(unsigned int *
>> minor_status=0x0124f914, gss_OID_desc_struct * mech_type=0x0243c0b0,
>> gss_name_struct * internal_name=0x0243a900, gss_buffer_desc_struct *
>> external_name=0x0124f8f4, gss_OID_desc_struct * *
>> name_type=0x0124f904)  Line 418 + 0x18 bytes    C
>>     gssapi32.dll!gss_display_name(unsigned int *
>> minor_status=0x0124f914, gss_name_struct * input_name=0x0243a820,
>> gss_buffer_desc_struct * output_name_buffer=0x0124f8f4,
>> gss_OID_desc_struct * * output_name_type=0x0124f904)  Line 103 + 0x1a
>> bytes    C
>>
>> Jeffrey Altman wrote:
>>     
>>> How have you confirmed that the issue you are experiencing is the one
>>> described in the Nov 2005?
>>>
>>> do you have a stack trace or a crash dump from the application?
>>>
>>> Hong Ye wrote:
>>>  
>>>       
>>>> latest release KFW 3.2.2.
>>>>
>>>> Jeffrey Altman wrote:
>>>>    
>>>>         
>>>>> Hong Ye wrote:
>>>>>  
>>>>>      
>>>>>           
>>>>>> Hi,
>>>>>>
>>>>>> Our authentication application developed using MIT kerberos crashed
>>>>>> in multi-thread environment on Windows. I found this post which
>>>>>> describes the same problem as we were seeing. The post was dated
>>>>>> Nov,2005. Has this problem been resolved in latest Kerberos library.
>>>>>> If not, is there work around?
>>>>>>
>>>>>> "Using the MEMORY credentials cache from multiple threads is not
>>>>>> thread-safe and crashes."
>>>>>> http://mailman.mit.edu/pipermail/krb5-bugs/2005-November/004061.html
>>>>>>
>>>>>> Any suggestions are appreciated,
>>>>>>
>>>>>> Hong
>>>>>>
>>>>>>             
>>>>>>             
>>>>> What version of KFW are you using?
>>>>>
>>>>>
>>>>>         
>>>>>           
>>>>     
>>>>         
>>