diff options
Diffstat (limited to 'src/backend/access/transam/xact.c')
| -rw-r--r-- | src/backend/access/transam/xact.c | 70 |
1 files changed, 25 insertions, 45 deletions
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c index f5a73caddba..d2ec35a7bae 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 1.195.4.3 2007/05/30 21:02:02 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.195.4.4 2008/01/03 21:25:00 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -117,7 +117,8 @@ typedef struct TransactionStateData * context */ ResourceOwner curTransactionOwner; /* my query resources */ List *childXids; /* subcommitted child XIDs */ - AclId currentUser; /* subxact start current_user */ + AclId prevUser; /* previous CurrentUserId setting */ + bool prevSecDefCxt; /* previous SecurityDefinerContext setting */ bool prevXactReadOnly; /* entry-time xact r/o state */ struct TransactionStateData *parent; /* back link to parent */ } TransactionStateData; @@ -149,7 +150,8 @@ static TransactionStateData TopTransactionStateData = { NULL, /* cur transaction context */ NULL, /* cur transaction resource owner */ NIL, /* subcommitted child Xids */ - 0, /* entry-time current userid */ + 0, /* previous CurrentUserId setting */ + false, /* previous SecurityDefinerContext setting */ false, /* entry-time xact r/o state */ NULL /* link to parent state block */ }; @@ -1390,18 +1392,14 @@ StartTransaction(void) /* * initialize current transaction state fields + * + * note: prevXactReadOnly is not used at the outermost level */ s->nestingLevel = 1; s->childXids = NIL; - - /* - * You might expect to see "s->currentUser = GetUserId();" here, but - * you won't because it doesn't work during startup; the userid isn't - * set yet during a backend's first transaction start. We only use - * the currentUser field in sub-transaction state structs. - * - * prevXactReadOnly is also valid only in sub-transactions. - */ + GetUserIdAndContext(&s->prevUser, &s->prevSecDefCxt); + /* SecurityDefinerContext should never be set outside a transaction */ + Assert(!s->prevSecDefCxt); /* * initialize other subsystems for new transaction @@ -1652,17 +1650,16 @@ AbortTransaction(void) AtAbort_ResourceOwner(); /* - * Reset user id which might have been changed transiently. We cannot - * use s->currentUser, but must get the session userid from - * miscinit.c. + * Reset user ID which might have been changed transiently. We need this + * to clean up in case control escaped out of a SECURITY DEFINER function + * or other local change of CurrentUserId; therefore, the prior value + * of SecurityDefinerContext also needs to be restored. * - * (Note: it is not necessary to restore session authorization here - * because that can only be changed via GUC, and GUC will take care of - * rolling it back if need be. However, an error within a SECURITY - * DEFINER function could send control here with the wrong current - * userid.) + * (Note: it is not necessary to restore session authorization + * setting here because that can only be changed via GUC, and GUC will + * take care of rolling it back if need be.) */ - SetUserId(GetSessionUserId()); + SetUserIdAndContext(s->prevUser, s->prevSecDefCxt); /* * do abort processing @@ -3395,6 +3392,12 @@ AbortSubTransaction(void) AtSubAbort_ResourceOwner(); /* + * Reset user ID which might have been changed transiently. (See notes + * in AbortTransaction.) + */ + SetUserIdAndContext(s->prevUser, s->prevSecDefCxt); + + /* * We can skip all this stuff if the subxact failed before creating * a ResourceOwner... */ @@ -3447,22 +3450,6 @@ AbortSubTransaction(void) } /* - * Reset user id which might have been changed transiently. Here we - * want to restore to the userid that was current at subxact entry. - * (As in AbortTransaction, we need not worry about the session - * userid.) - * - * Must do this after AtEOXact_GUC to handle the case where we entered - * the subxact inside a SECURITY DEFINER function (hence current and - * session userids were different) and then session auth was changed - * inside the subxact. GUC will reset both current and session - * userids to the entry-time session userid. This is right in every - * other scenario so it seems simplest to let GUC do that and fix it - * here. - */ - SetUserId(s->currentUser); - - /* * Restore the upper transaction's read-only state, too. This should * be redundant with GUC's cleanup but we may as well do it for * consistency with the commit case. @@ -3516,13 +3503,6 @@ PushTransaction(void) { TransactionState p = CurrentTransactionState; TransactionState s; - AclId currentUser; - - /* - * At present, GetUserId cannot fail, but let's not assume that. Get - * the ID before entering the critical code sequence. - */ - currentUser = GetUserId(); /* * We keep subtransaction state nodes in TopTransactionContext. @@ -3553,7 +3533,7 @@ PushTransaction(void) s->savepointLevel = p->savepointLevel; s->state = TRANS_DEFAULT; s->blockState = TBLOCK_SUBBEGIN; - s->currentUser = currentUser; + GetUserIdAndContext(&s->prevUser, &s->prevSecDefCxt); s->prevXactReadOnly = XactReadOnly; CurrentTransactionState = s; |