From: Tom Lane Date: Sun, 24 Jan 2010 21:49:39 +0000 (+0000) Subject: Fix assorted core dumps and Assert failures that could occur during X-Git-Tag: REL8_3_10~40 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=7309f3340c46bdb8109e0465becbc078b1e1858a;p=postgresql Fix assorted core dumps and Assert failures that could occur during AbortTransaction or AbortSubTransaction, when trying to clean up after an error that prevented (sub)transaction start from completing: * access to TopTransactionResourceOwner that might not exist * assert failure in AtEOXact_GUC, if AtStart_GUC not called yet * assert failure or core dump in AfterTriggerEndSubXact, if AfterTriggerBeginSubXact not called yet Per testing by injecting elog(ERROR) at successive steps in StartTransaction and StartSubTransaction. It's not clear whether all of these cases could really occur in the field, but at least one of them is easily exposed by simple stress testing, as per my accidental discovery yesterday. --- diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c index 2c440ca1fa..cc38c6ff13 100644 --- a/src/backend/access/transam/xact.c +++ b/src/backend/access/transam/xact.c @@ -10,7 +10,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.257.2.5 2009/12/09 21:58:16 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.257.2.6 2010/01/24 21:49:39 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -2097,38 +2097,41 @@ AbortTransaction(void) /* * Post-abort cleanup. See notes in CommitTransaction() concerning - * ordering. + * ordering. We can skip all of it if the transaction failed before + * creating a resource owner. */ + if (TopTransactionResourceOwner != NULL) + { + CallXactCallbacks(XACT_EVENT_ABORT); - CallXactCallbacks(XACT_EVENT_ABORT); - - ResourceOwnerRelease(TopTransactionResourceOwner, - RESOURCE_RELEASE_BEFORE_LOCKS, - false, true); - AtEOXact_Buffers(false); - AtEOXact_RelationCache(false); - AtEOXact_Inval(false); - smgrDoPendingDeletes(false); - AtEOXact_MultiXact(); - ResourceOwnerRelease(TopTransactionResourceOwner, - RESOURCE_RELEASE_LOCKS, - false, true); - ResourceOwnerRelease(TopTransactionResourceOwner, - RESOURCE_RELEASE_AFTER_LOCKS, - false, true); - AtEOXact_CatCache(false); + ResourceOwnerRelease(TopTransactionResourceOwner, + RESOURCE_RELEASE_BEFORE_LOCKS, + false, true); + AtEOXact_Buffers(false); + AtEOXact_RelationCache(false); + AtEOXact_Inval(false); + smgrDoPendingDeletes(false); + AtEOXact_MultiXact(); + ResourceOwnerRelease(TopTransactionResourceOwner, + RESOURCE_RELEASE_LOCKS, + false, true); + ResourceOwnerRelease(TopTransactionResourceOwner, + RESOURCE_RELEASE_AFTER_LOCKS, + false, true); + AtEOXact_CatCache(false); - AtEOXact_GUC(false, 1); - AtEOXact_SPI(false); - AtEOXact_xml(); - AtEOXact_on_commit_actions(false); - AtEOXact_Namespace(false); - smgrabort(); - AtEOXact_Files(); - AtEOXact_ComboCid(); - AtEOXact_HashTables(false); - AtEOXact_PgStat(false); - pgstat_report_xact_timestamp(0); + AtEOXact_GUC(false, 1); + AtEOXact_SPI(false); + AtEOXact_xml(); + AtEOXact_on_commit_actions(false); + AtEOXact_Namespace(false); + smgrabort(); + AtEOXact_Files(); + AtEOXact_ComboCid(); + AtEOXact_HashTables(false); + AtEOXact_PgStat(false); + pgstat_report_xact_timestamp(0); + } /* * State remains TRANS_ABORT until CleanupTransaction(). diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c index 07033dc02f..51ffef01bf 100644 --- a/src/backend/commands/trigger.c +++ b/src/backend/commands/trigger.c @@ -7,7 +7,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.227.2.3 2009/10/27 20:14:39 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.227.2.4 2010/01/24 21:49:39 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -3060,10 +3060,9 @@ AfterTriggerEndSubXact(bool isCommit) /* * Pop the prior state if needed. */ - Assert(my_level < afterTriggers->maxtransdepth); - if (isCommit) { + Assert(my_level < afterTriggers->maxtransdepth); /* If we saved a prior state, we don't need it anymore */ state = afterTriggers->state_stack[my_level]; if (state != NULL) @@ -3095,7 +3094,15 @@ AfterTriggerEndSubXact(bool isCommit) else { /* - * Aborting. We don't really need to release the subxact's event_cxt, + * Aborting. It is possible subxact start failed before calling + * AfterTriggerBeginSubXact, in which case we mustn't risk touching + * stack levels that aren't there. + */ + if (my_level >= afterTriggers->maxtransdepth) + return; + + /* + * We don't really need to release the subxact's event_cxt, * since it will go away anyway when CurTransactionContext gets reset, * but doing so early in subxact abort helps free space we might need. * diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c index df52fb8b09..2c86df6b56 100644 --- a/src/backend/utils/misc/guc.c +++ b/src/backend/utils/misc/guc.c @@ -10,7 +10,7 @@ * Written by Peter Eisentraut . * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.432.2.5 2009/12/09 21:58:17 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.432.2.6 2010/01/24 21:49:39 tgl Exp $ * *-------------------------------------------------------------------- */ @@ -3518,7 +3518,14 @@ AtEOXact_GUC(bool isCommit, int nestLevel) bool still_dirty; int i; - Assert(nestLevel > 0 && nestLevel <= GUCNestLevel); + /* + * Note: it's possible to get here with GUCNestLevel == nestLevel-1 during + * abort, if there is a failure during transaction start before + * AtStart_GUC is called. + */ + Assert(nestLevel > 0 && + (nestLevel <= GUCNestLevel || + (nestLevel == GUCNestLevel + 1 && !isCommit))); /* Quick exit if nothing's changed in this transaction */ if (!guc_dirty)