macOS crash during init_context_from_config_file

[desoi]

Describe the bug
I'm seeing frequent crashes on a previously stable macOS web server. The problem seems to go away for days after restarting the httpd process, but then returns with increasing frequency. Crash report below with operating system details and backtrace.

-------------------------------------
Translated Report (Full Report Below)
-------------------------------------

Process:               httpd [54877]
Path:                  /opt/homebrew/*/httpd
Identifier:            httpd
Version:               ???
Code Type:             ARM-64 (Native)
Parent Process:        httpd [6040]
Responsible:           httpd [6040]
User ID:               502

Date/Time:             2023-11-30 07:06:00.0651 -0600
OS Version:            macOS 12.7 (21G816)
Report Version:        12
Anonymous UUID:        750F146C-B2B5-BECA-EC21-1FEC0471D5AC


Time Awake Since Boot: 1000000 seconds

System Integrity Protection: enabled

Crashed Thread:        0  Dispatch queue: com.apple.root.utility-qos

Exception Type:        EXC_BAD_ACCESS (SIGSEGV)
Exception Codes:       KERN_INVALID_ADDRESS at 0x0000000000000110
Exception Codes:       0x0000000000000001, 0x0000000000000110
Exception Note:        EXC_CORPSE_NOTIFY

VM Region Info: 0x110 is not in any region.  Bytes before following region: 105553518919408
      REGION TYPE                    START - END         [ VSIZE] PRT/MAX SHRMOD  REGION DETAIL
      UNUSED SPACE AT START
--->  
      MALLOC_NANO (reserved)   600018000000-600020000000 [128.0M] rw-/rwx SM=NUL  ...(unallocated)

Application Specific Information:
*** multi-threaded process forked ***
crashed on child side of fork pre-exec


Kernel Triage:
VM - pmap_enter failed with resource shortage
VM - pmap_enter failed with resource shortage


Thread 0 Crashed::  Dispatch queue: com.apple.root.utility-qos
0   libdispatch.dylib             	       0x199dd825c _dispatch_apply_with_attr_f + 1136
1   libdispatch.dylib             	       0x199dd8234 _dispatch_apply_with_attr_f + 1096
2   libdispatch.dylib             	       0x199dd847c dispatch_apply + 108
3   CoreFoundation                	       0x19a172a80 __104-[CFPrefsSearchListSource synchronouslySendDaemonMessage:andAgentMessage:andDirectMessage:replyHandler:]_block_invoke.92 + 132
4   CoreFoundation                	       0x19a007e8c CFPREFERENCES_IS_WAITING_FOR_SYSTEM_AND_USER_CFPREFSDS + 100
5   CoreFoundation                	       0x19a007ccc -[CFPrefsSearchListSource synchronouslySendDaemonMessage:andAgentMessage:andDirectMessage:replyHandler:] + 232
6   CoreFoundation                	       0x19a00649c -[CFPrefsSearchListSource alreadylocked_generationCountFromListOfSources:count:] + 252
7   CoreFoundation                	       0x19a006178 -[CFPrefsSearchListSource alreadylocked_getDictionary:] + 468
8   CoreFoundation                	       0x19a005cec -[CFPrefsSearchListSource alreadylocked_copyValueForKey:] + 172
9   CoreFoundation                	       0x19a005c20 -[CFPrefsSource copyValueForKey:] + 60
10  CoreFoundation                	       0x19a005bcc __76-[_CFXPreferences copyAppValueForKey:identifier:container:configurationURL:]_block_invoke + 44
11  CoreFoundation                	       0x199ffe9e0 __108-[_CFXPreferences(SearchListAdditions) withSearchListForIdentifier:container:cloudConfigurationURL:perform:]_block_invoke + 384
12  CoreFoundation                	       0x19a173350 -[_CFXPreferences withSearchListForIdentifier:container:cloudConfigurationURL:perform:] + 384
13  CoreFoundation                	       0x199ffe394 -[_CFXPreferences copyAppValueForKey:identifier:container:configurationURL:] + 168
14  CoreFoundation                	       0x199ffe2b0 _CFPreferencesCopyAppValueWithContainerAndConfiguration + 128
15  Heimdal                       	       0x1a5d4cb80 init_context_from_config_file + 2732
16  Heimdal                       	       0x1a5d33944 krb5_set_config_files + 392
17  Heimdal                       	       0x1a5d33284 krb5_init_context_flags + 308
18  Heimdal                       	       0x1a5d33144 krb5_init_context + 32
19  Kerberos                      	       0x1a7fc32e8 mshim_ctx + 64
20  Kerberos                      	       0x1a7fc16e4 context_new_ccache_iterator + 92
21  libkrb5.3.3.dylib             	       0x1017accc8 api_macos_ptcursor_next + 220
22  libkrb5.3.3.dylib             	       0x1017a9f0c krb5_cccol_cursor_next + 76
23  libkrb5.3.3.dylib             	       0x1017aa1f4 krb5_cccol_have_content + 92
24  libgssapi_krb5.2.2.dylib      	       0x1016a1f58 acquire_cred_context + 1668
25  libgssapi_krb5.2.2.dylib      	       0x1016a185c acquire_cred_from + 688
26  libgssapi_krb5.2.2.dylib      	       0x101693b8c gss_add_cred_from + 1108
27  libgssapi_krb5.2.2.dylib      	       0x101693568 gss_acquire_cred_from + 308
28  libgssapi_krb5.2.2.dylib      	       0x101693428 gss_acquire_cred + 36
29  libpq.5.dylib                 	       0x1012a9db8 pg_GSS_have_cred_cache + 60
30  libpq.5.dylib                 	       0x10129927c PQconnectPoll + 5600
31  libpq.5.dylib                 	       0x10129623c connectDBComplete + 304
32  libpq.5.dylib                 	       0x1012963a8 PQconnectdb + 44
33  libphp.so                     	       0x10229569c pdo_pgsql_handle_factory + 328
34  libphp.so                     	       0x102282230 zim_PDO___construct + 1496
35  libphp.so                     	       0x10249bd0c ZEND_DO_FCALL_SPEC_RETVAL_UNUSED_HANDLER + 304
36  libphp.so                     	       0x102479868 execute_ex + 52
37  libphp.so                     	       0x10244b314 zend_call_function + 1332
38  libphp.so                     	       0x10236cef0 zif_call_user_func_array + 136
39  libphp.so                     	       0x1024b83e4 ZEND_DO_FCALL_BY_NAME_SPEC_RETVAL_USED_HANDLER + 264
40  libphp.so                     	       0x102479868 execute_ex + 52
41  libphp.so                     	       0x102479a64 zend_execute + 288
42  libphp.so                     	       0x102459d84 zend_execute_scripts + 156
43  libphp.so                     	       0x1023ff9a8 php_execute_script + 460
44  libphp.so                     	       0x10253efa8 php_handler + 1024
45  httpd                         	       0x100cc61a4 ap_run_handler + 64
46  httpd                         	       0x100cc687c ap_invoke_handler + 264
47  httpd                         	       0x100cfe364 ap_internal_redirect + 60
48  mod_rewrite.so                	       0x10204b6d8 handler_redirect + 136
49  httpd                         	       0x100cc61a4 ap_run_handler + 64
50  httpd                         	       0x100cc687c ap_invoke_handler + 264
51  httpd                         	       0x100cfdf3c ap_process_async_request + 792
52  httpd                         	       0x100cfdfec ap_process_request + 24
53  httpd                         	       0x100cfae64 ap_process_http_connection + 344
54  httpd                         	       0x100cd785c ap_run_process_connection + 64
55  mod_mpm_prefork.so            	       0x1010e23ec child_main + 1092
56  mod_mpm_prefork.so            	       0x1010e1e74 make_child + 436
57  mod_mpm_prefork.so            	       0x1010e18b0 prefork_run + 2056
58  httpd                         	       0x100cd9f30 ap_run_mpm + 84
59  httpd                         	       0x100ccd3b4 main + 2260
60  dyld                          	       0x100fd108c start + 520

[jaltman]

Thank you for the report but Apple's fork of Heimdal is independent from this Heimdal. Frames 20 and 19 are Apple's Kerberos 5 shim which exposes the MIT Kerberos 5 API and frames 18 through 15 are Apple's private fork of Heimdal.

Assuming this crash is present in this Heimdal and it was fixed in this Heimdal, Apple wouldn't pull the fix from this project.

[desoi]

Thank you very much for the details. I'll have to see if there is a way to prevent PostgreSQL from using GSSAPI.