Hmm, far less likely, but still: Crashed Thread: 0 Dispatch queue: com.apple.main-thread
Exception Type: EXC_CRASH (SIGSEGV) Exception Codes: 0x0000000000000000, 0x0000000000000000 Exception Note: EXC_CORPSE_NOTIFY Termination Signal: Segmentation fault: 11 Termination Reason: Namespace SIGNAL, Code 0xb Terminating Process: httpd [6106] Application Specific Information: crashed on child side of fork pre-exec Thread 0 Crashed:: Dispatch queue: com.apple.main-thread 0 libsystem_malloc.dylib 0x00007fff6b2e1c8c free_tiny + 243 1 libcrypto.1.1.dylib 0x0000000101363484 OPENSSL_LH_delete + 228 2 libcrypto.1.1.dylib 0x00000001013730f9 OBJ_NAME_remove + 105 3 libcrypto.1.1.dylib 0x000000010136368a OPENSSL_LH_doall + 74 4 libcrypto.1.1.dylib 0x0000000101373338 OBJ_NAME_cleanup + 72 5 libcrypto.1.1.dylib 0x00000001013577de evp_cleanup_int + 14 6 libcrypto.1.1.dylib 0x0000000101360ccf OPENSSL_cleanup + 335 7 libsystem_c.dylib 0x00007fff6b1da3d6 __cxa_finalize_ranges + 326 8 libsystem_c.dylib 0x00007fff6b1da6b3 exit + 55 9 mod_mpm_event.so 0x0000000101531546 clean_child_exit + 54 (event.c:768) 10 mod_mpm_event.so 0x0000000101531382 child_main + 1698 (event.c:2551) 11 mod_mpm_event.so 0x0000000101530c84 make_child + 436 12 mod_mpm_event.so 0x000000010152f7e5 event_run + 1093 (event.c:3256) 13 httpd 0x0000000100f0366b ap_run_mpm + 75 (mpm_common.c:101) 14 httpd 0x0000000100ef4679 main + 2233 (main.c:848) 15 libdyld.dylib 0x00007fff6b1343d5 start + 1 Thread 1: 0 libsystem_pthread.dylib 0x00007fff6b327e02 pthread_rwlock_wrlock + 0 1 libcrypto.1.1.dylib 0x00000001013be209 CRYPTO_THREAD_write_lock + 9 2 libcrypto.1.1.dylib 0x000000010138f3a6 RAND_get_rand_method + 54 3 libcrypto.1.1.dylib 0x000000010138f675 RAND_priv_bytes + 21 4 libcrypto.1.1.dylib 0x00000001012b4bb2 bnrand + 178 5 libcrypto.1.1.dylib 0x00000001012b2f49 BN_generate_prime_ex + 665 6 libcrypto.1.1.dylib 0x00000001013979b7 RSA_generate_multi_prime_key + 1783 7 libcrypto.1.1.dylib 0x000000010139c2d0 pkey_rsa_keygen + 160 8 libcrypto.1.1.dylib 0x000000010135bc5b EVP_PKEY_keygen + 91 9 mod_md.so 0x0000000101552bb4 gen_rsa + 132 (md_crypt.c:464) 10 mod_md.so 0x000000010154a797 md_acme_acct_register + 887 (md_acme_acct.c:591) 11 mod_md.so 0x000000010154c83c md_acme_drive_set_acct + 1020 (md_acme_drive.c:158) 12 mod_md.so 0x000000010154fd61 md_acmev2_drive_renew + 81 (md_acmev2_drive.c:102) 13 mod_md.so 0x000000010154da40 acme_driver_renew + 1520 14 mod_md.so 0x000000010155f196 run_renew + 262 (md_reg.c:1066) 15 mod_md.so 0x0000000101564179 md_util_pool_vdo + 185 (md_util.c:54) 16 mod_md.so 0x000000010155f08a md_reg_renew + 42 (md_reg.c:1075) 17 mod_md.so 0x00000001015423dc run_watchdog + 668 (mod_md_drive.c:127) 18 mod_watchdog.so 0x00000001014fd4fc wd_worker + 636 (mod_watchdog.c:202) 19 libsystem_pthread.dylib 0x00007fff6b3282eb _pthread_body + 126 20 libsystem_pthread.dylib 0x00007fff6b32b249 _pthread_start + 66 21 libsystem_pthread.dylib 0x00007fff6b32740d thread_start + 13 > Am 25.09.2019 um 14:46 schrieb Stefan Eissing <stefan.eiss...@greenbytes.de>: > > The patch looks nice. Running it in my test suite over and over without any > crash showing up! > > Great work! > >> Am 25.09.2019 um 13:24 schrieb Yann Ylavic <ylavic....@gmail.com>: >> >> On Wed, Sep 25, 2019 at 11:54 AM Stefan Eissing >> <stefan.eiss...@greenbytes.de> wrote: >>> >>> Looking for help on an issue in mod_watchdog use and child exits. >>> >>> Occasionally a httpd child crashes due to races between child pool being >>> destroyed while watchdog threads are still running. The crash manifests >>> most likely when OPENSSL_cleanup runs while another thread is generated a >>> private key (singe that takes relatively long). >>> >>> Beside the crash report, nothing else really fails since the child is >>> terminating anyway and no requests are onoing. But still, it's not a nice >>> thing. >>> >>> Do you see an easy way to avoid this? >> >> AFAICT, clean_child_exit() destroys pchild only, and pconf is still >> alive at exit() time. >> Couldn't we use pconf only in child_init hooks of mod_ssl and mod_watchdog? >> Does something like the attached patch fixes the crash? >> <some_pchild_to_pconf.diff> >
