WATCHDOG: Restart providers with SIGUSR2 after time drift Restarting the providers using the already implemented SIGUSR2 (for method .resetOffline, used after netlink detects an interface change) when a time drift is detected, ensures that affected connection retries (e.g. LDAP) will be rescheduled immediately instead of having to wait the time shifted to return to its normal execution. Resolves: https://pagure.io/SSSD/sssd/issue/3285 Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com> Reviewed-by: Fabiano Fidêncio <fidencio@redhat.com>

UTIL: Remove signal.h from util/util.h signal.h is not used directly by util/util.h. The header file signal.h must be included in 8 files and removing it from util.h it had to be added only to 5 missing file. But util/util.h is include in 377 files Reviewed-by: Fabiano Fidêncio <fidencio@redhat.com>

WATCHDOG: Avoid non async-signal-safe from the signal_handler While debugging rhbz#1396912 a deadlock on sssd_be was noticed[0] and it's been caused by the use of non async-signal-safe functions from the signal_handler (please, see man 7 signal for more info about which are the async-signal-safe functions that can be used). In order to work this situation around a pipe has been added to the watchdog_ctx structure and, in case of clock screw, a single byte is written to this pipe (which is an async-signal-safe operation) and the logic currently done by the timer handler to reset the watchdog will be done inside the fd handler in a safe way. With this patch we ended up losing some debug messages as orderly_shutdown() has been replaced by kill(-getpgrp(), SIGTERM) (or _exit(1) considering the cases where setting up the process group during the server_setup() has failed). Personally I don't think is worth the trouble to try to log those messages properly in this specific case. It's really worth to mention that a proper fix the clock screw situation should be implemented on samba's side, by having tevent using monotonic (or boottime) clock. [0]: [root@dusan ~]# pstack 17922 #0 __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95 #1 0x00007fe707d04f93 in _L_lock_14932 () from /lib64/libc.so.6 #2 0x00007fe707d02013 in __GI___libc_malloc (bytes=140630248638304, bytes@entry=15) at malloc.c:2891 #3 0x00007fe707d0888a in __GI___strdup (s=0x7fe707dff4f7 "/etc/localtime") at strdup.c:42 #4 0x00007fe707d31b61 in tzset_internal (always=<optimized out>, explicit=explicit@entry=1) at tzset.c:438 #5 0x00007fe707d32523 in __tz_convert (timer=timer@entry=0x7ffcd5d2b090, use_localtime=use_localtime@entry=1, tp=tp@entry=0x7fe708041d40 <_tmbuf>) at tzset.c:621 #6 0x00007fe707d30521 in __GI_localtime (t=t@entry=0x7ffcd5d2b090) at localtime.c:42 #7 0x00007fe70886c7b0 in sss_vdebug_fn (file=<optimized out>, line=<optimized out>, function=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=16, flags=flags@entry=0, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n", ap=ap@entry=0x7ffcd5d2b130) at src/util/debug.c:248 #8 0x00007fe70886c995 in sss_debug_fn (file=file@entry=0x7fe70bff263b "src/util/util_watchdog.c", line=line@entry=82, function=function@entry=0x7fe70bff27f0 <__FUNCTION__.9379> "watchdog_handler", level=level@entry=16, format=format@entry=0x7fe70bff2760 "Watchdog timer overflow, killing process!\n") at src/util/debug.c:284 #9 0x00007fe70bfdb409 in watchdog_handler (sig=<optimized out>) at src/util/util_watchdog.c:81 #10 <signal handler called> #11 0x00007fe707cff664 in _int_malloc (av=av@entry=0x7fe70803c760 <main_arena>, bytes=bytes@entry=151) at malloc.c:3494 #12 0x00007fe707d01fbc in __GI___libc_malloc (bytes=bytes@entry=151) at malloc.c:2893 #13 0x00007fe708450749 in __talloc_with_prefix (prefix_len=0, size=55, context=0x7fe718373210) at ../talloc.c:668 #14 __talloc (size=55, context=0x7fe718373210) at ../talloc.c:708 #15 _talloc_named_const (name=0x7fe70bb7015d "../common/ldb_pack.c:425", size=55, context=0x7fe718373210) at ../talloc.c:865 #16 talloc_named_const (context=<optimized out>, size=size@entry=55, name=name@entry=0x7fe70bb7015d "../common/ldb_pack.c:425") at ../talloc.c:1606 #17 0x00007fe70bb61803 in ldb_unpack_data_only_attr_list (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=0x7fe7184aa1e0, list=list@entry=0x0, list_size=list_size@entry=0, nb_elements_in_db=nb_elements_in_db@entry=0x0) at ../common/ldb_pack.c:425 #18 0x00007fe70bb61a7d in ldb_unpack_data (ldb=ldb@entry=0x7fe70e4d52c0, data=data@entry=0x7ffcd5d2b990, message=<optimized out>) at ../common/ldb_pack.c:470 #19 0x00007fe6fdc29b46 in ltdb_parse_data_unpack (key=..., data=..., private_data=0x7ffcd5d2ba70) at ../ldb_tdb/ldb_search.c:249 #20 0x00007fe70a5e0a24 in tdb_parse_data (tdb=tdb@entry=0x7fe70e4eaa10, key=..., offset=15619748, len=414772, parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/io.c:637 #21 0x00007fe70a5dc1fc in tdb_parse_record (tdb=0x7fe70e4eaa10, key=..., parser=parser@entry=0x7fe6fdc29b10 <ltdb_parse_data_unpack>, private_data=private_data@entry=0x7ffcd5d2ba70) at ../common/tdb.c:253 #22 0x00007fe6fdc29e7b in ltdb_search_dn1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, msg=msg@entry=0x7fe7184aa1e0) at ../ldb_tdb/ldb_search.c:287 #23 0x00007fe6fdc2acbb in ltdb_dn_list_load (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183c4940, list=list@entry=0x7fe7183c3a30) at ../ldb_tdb/ldb_index.c:181 #24 0x00007fe6fdc2bbbb in ltdb_index_add1 (module=module@entry=0x7fe70e4eab50, dn=dn@entry=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", v_idx=v_idx@entry=0, el=<optimized out>, el=<optimized out>) at ../ldb_tdb/ldb_index.c:1134 #25 0x00007fe6fdc2c62c in ltdb_index_add_el (el=0x7fe7184aa3e0, dn=0x7fe7183bf3e0 "name=testuser7045@domain.com,cn=users,cn=DOMAIN.COM,cn=sysdb", module=0x7fe70e4eab50) at ../ldb_tdb/ldb_index.c:1180 #26 ltdb_index_add_element (module=module@entry=0x7fe70e4eab50, dn=<optimized out>, el=el@entry=0x7fe7184aa3e0) at ../ldb_tdb/ldb_index.c:1290 #27 0x00007fe6fdc290bb in ltdb_modify_internal (module=module@entry=0x7fe70e4eab50, msg=0x7fe7183bf0c0, req=req@entry=0x7fe7183bdc10) at ../ldb_tdb/ldb_tdb.c:903 #28 0x00007fe6fdc2958a in ltdb_modify (ctx=0x7fe7183c2950, ctx=0x7fe7183c2950) at ../ldb_tdb/ldb_tdb.c:998 #29 ltdb_callback (ev=<optimized out>, te=<optimized out>, t=..., private_data=<optimized out>) at ../ldb_tdb/ldb_tdb.c:1380 #30 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4d2890) at ../tevent_timed.c:341 #31 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4d2890, location=<optimized out>) at ../tevent_epoll.c:911 #32 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4d2890, location=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent_standard.c:114 #33 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4d2890, location=location@entry=0x7fe70bb72ec5 "../common/ldb.c:631") at ../tevent.c:533 #34 0x00007fe70bb6bc4f in ldb_wait (handle=0x7fe7183c4530, type=<optimized out>) at ../common/ldb.c:631 #35 0x00007fe70bb6c793 in ldb_autotransaction_request (ldb=0x7fe70e4d52c0, req=0x7fe7183bdc10) at ../common/ldb.c:573 #36 0x00007fe70bb6d263 in ldb_modify (ldb=ldb@entry=0x7fe70e4d52c0, message=<optimized out>) at ../common/ldb.c:1655 #37 0x00007fe70bfa2ab5 in sysdb_set_cache_entry_attr (ldb=0x7fe70e4d52c0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bf680, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1159 #38 0x00007fe70bfa304d in sysdb_rep_ts_entry_attr (sysdb=0x7fe70e4eadd0, attrs=0x7fe7183bf680, entry_dn=0x7fe7183c4760) at src/db/sysdb_ops.c:1218 #39 sysdb_set_ts_entry_attr (sysdb=sysdb@entry=0x7fe70e4eadd0, entry_dn=entry_dn@entry=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1248 #40 0x00007fe70bfa4aa9 in sysdb_set_entry_attr (sysdb=0x7fe70e4eadd0, entry_dn=0x7fe7183c4760, attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1199 #41 0x00007fe70bfa4b5f in sysdb_set_user_attr (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", attrs=attrs@entry=0x7fe7183bb840, mod_op=mod_op@entry=2) at src/db/sysdb_ops.c:1285 #42 0x00007fe70bfa58c3 in sysdb_add_user (domain=domain@entry=0x7fe70e4d62f0, name=name@entry=0x7fe7183c01f0 "testuser7045@domain.com", uid=uid@entry=1415408147, gid=<optimized out>, gid@entry=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:1928 #43 0x00007fe70bfab271 in sysdb_store_new_user (now=1481105315, cache_timeout=5400, attrs=0x7fe7183bb840, orig_dn=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", shell=0x0, homedir=0x0, gecos=0x7fe710465d00 "Test User7045", gid=1415400513, uid=1415408147, name=0x7fe7183c01f0 "testuser7045@domain.com", domain=0x7fe70e4d62f0) at src/db/sysdb_ops.c:2549 #44 sysdb_store_user (domain=domain@entry=0x7fe70e4d62f0, name=0x7fe7183c01f0 "testuser7045@domain.com", pwd=pwd@entry=0x0, uid=1415408147, gid=1415400513, gecos=gecos@entry=0x7fe710465d00 "Test User7045", homedir=homedir@entry=0x0, shell=shell@entry=0x0, orig_dn=orig_dn@entry=0x7fe710465940 "CN=Test User7045,OU=Sales,DC=DOMAIN,DC=COM", attrs=attrs@entry=0x7fe7183bb840, remove_attrs=0x7fe7183c08a0, cache_timeout=cache_timeout@entry=5400, now=now@entry=1481105315) at src/db/sysdb_ops.c:2499 #45 0x00007fe6fba0d9f9 in sdap_save_user (memctx=memctx@entry=0x7fe70e544ee0, opts=opts@entry=0x7fe70e518400, dom=dom@entry=0x7fe70e4d62f0, attrs=<optimized out>, _usn_value=_usn_value@entry=0x7ffcd5d2c260, now=now@entry=1481105315) at src/providers/ldap/sdap_async_users.c:509 #46 0x00007fe6fba0df9a in sdap_save_users (memctx=memctx@entry=0x7fe70e544e40, sysdb=0x7fe70e4eadd0, dom=0x7fe70e4d62f0, opts=0x7fe70e518400, users=<optimized out>, num_users=10006, _usn_value=_usn_value@entry=0x7fe70e544e60) at src/providers/ldap/sdap_async_users.c:572 #47 0x00007fe6fba0e460 in sdap_get_users_done (subreq=<optimized out>) at src/providers/ldap/sdap_async_users.c:938 #48 0x00007fe6fba0c9d5 in sdap_search_user_process (subreq=0x0) at src/providers/ldap/sdap_async_users.c:814 #49 0x00007fe6fba07379 in generic_ext_search_handler (subreq=0x0, opts=<optimized out>) at src/providers/ldap/sdap_async.c:1689 #50 0x00007fe6fba0991b in sdap_get_generic_op_finished (op=<optimized out>, reply=<optimized out>, error=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:1621 #51 0x00007fe6fba083cd in sdap_process_message (ev=<optimized out>, sh=<optimized out>, msg=0x7fe70e5f9ce0) at src/providers/ldap/sdap_async.c:353 #52 sdap_process_result (ev=<optimized out>, pvt=<optimized out>) at src/providers/ldap/sdap_async.c:197 #53 0x00007fe708664b4f in tevent_common_loop_timer_delay (ev=ev@entry=0x7fe70e4cbc30) at ../tevent_timed.c:341 #54 0x00007fe708665b5a in epoll_event_loop_once (ev=0x7fe70e4cbc30, location=<optimized out>) at ../tevent_epoll.c:911 #55 0x00007fe708664257 in std_event_loop_once (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:114 #56 0x00007fe70866040d in _tevent_loop_once (ev=ev@entry=0x7fe70e4cbc30, location=location@entry=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:533 #57 0x00007fe7086605ab in tevent_common_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent.c:637 #58 0x00007fe7086641f7 in std_event_loop_wait (ev=0x7fe70e4cbc30, location=0x7fe70bfee8e7 "src/util/server.c:702") at ../tevent_standard.c:140 #59 0x00007fe70bfd1993 in server_loop (main_ctx=0x7fe70e4cd080) at src/util/server.c:702 #60 0x00007fe70c84cb82 in main (argc=8, argv=<optimized out>) at src/providers/data_provider_be.c:587 Resolves: https://fedorahosted.org/sssd/ticket/3266 Signed-off-by: Fabiano Fidêncio <fidencio@redhat.com> Reviewed-by: Pavel Březina <pbrezina@redhat.com> Reviewed-by: Jakub Hrozek <jhrozek@redhat.com> Reviewed-by: Simo Sorce <simo@redhat.com>

WATCHDOG: define and use _MAX_TICKS as 3 Instead of using the number 3 directly, let's introduce and use WATCHDOG_MAX_TICKS. Reviewed-by: Petr Čech <pcech@redhat.com>

watchdog: cope with time shift When a time is changed into the past during sssd runtime (e.g. on boot during time correction), it is possible that we never hit watchdog tevent timer since it is based on system time. This patch adds a past-time shift detection mechanism. If a time shift is detected we restart watchdog. Resolves: https://fedorahosted.org/sssd/ticket/3154 Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com> Reviewed-by: Fabiano Fidêncio <fidencio@redhat.com>

UTIL: Fix warning Wmissing-braces Older versions of gcc does not like initialisation of struct sigevent because the first member of structure is union (sigval_t) src/util/util_watchdog.c: In function 'setup_watchdog': src/util/util_watchdog.c:77:12: warning: missing braces around initializer [-Wmissing-braces] struct sigevent sev = { 0 }; ^ src/util/util_watchdog.c:77:12: warning: (near initialization for 'sev.sigev_value') [-Wmissing-braces] src/util/util_watchdog.c:77:12: warning: initialization makes integer from pointer without a cast src/util/util_watchdog.c:77:12: warning: (near initialization for 'sev.sigev_value.sival_int') Reviewed-by: Sumit Bose <sbose@redhat.com>

Util: Add watchdog helper The watchdog uses a kernel timer to issue a signal to the process. It checks if the ticker is not being reset by the main event loop, which would indicate that the process got stuck. At the same time it sets a tevent timer to clear the watchdog ticker, so that the watchdog handler is kept happy. If the watchdog detects that the timer event failed to reset the watchdog for three times in a row then the process is killed. Normally the monitor will detect the child terminated and will rescheduled it. Related: https://fedorahosted.org/sssd/ticket/2921 Reviewed-by: Jakub Hrozek <jhrozek@redhat.com> Reviewed-by: Pavel Březina <pbrezina@redhat.com>