From 4b8b3562e1e6e5b4abd5e9326f71af73e98dc604 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 18 Jun 2021 12:09:22 -0400 Subject: [PATCH] Avoid scribbling on input node tree in CREATE/ALTER DOMAIN. This works fine in the "simple Query" code path; but if the statement is in the plan cache then it's corrupted for future re-execution. Apply copyObject() to protect the original tree from modification, as we've done elsewhere. This narrow fix is applied only to the back branches. In HEAD, the problem was fixed more generally by commit 7c337b6b5; but that changed ProcessUtility's API, so it's infeasible to back-patch. Per bug #17053 from Charles Samborski. Discussion: https://postgr.es/m/931771.1623893989@sss.pgh.pa.us Discussion: https://postgr.es/m/17053-3ca3f501bbc212b4@postgresql.org --- src/backend/commands/typecmds.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c index f64787de0c..6338276b5f 100644 --- a/src/backend/commands/typecmds.c +++ b/src/backend/commands/typecmds.c @@ -908,10 +908,12 @@ DefineDomain(CreateDomainStmt *stmt) pstate = make_parsestate(NULL); /* - * Cook the constr->raw_expr into an expression. Note: - * name is strictly for error message + * Cook the constr->raw_expr into an expression; copy it + * in case the input is in plan cache. Note: name is used + * only for error messages. */ - defaultExpr = cookDefault(pstate, constr->raw_expr, + defaultExpr = cookDefault(pstate, + copyObject(constr->raw_expr), basetypeoid, basetypeMod, domainName); @@ -2262,10 +2264,10 @@ AlterDomainDefault(List *names, Node *defaultRaw) pstate = make_parsestate(NULL); /* - * Cook the colDef->raw_expr into an expression. Note: Name is - * strictly for error message + * Cook the raw default into an expression; copy it in case the input + * is in plan cache. Note: name is used only for error messages. */ - defaultExpr = cookDefault(pstate, defaultRaw, + defaultExpr = cookDefault(pstate, copyObject(defaultRaw), typTup->typbasetype, typTup->typtypmod, NameStr(typTup->typname)); @@ -3136,7 +3138,12 @@ domainAddConstraint(Oid domainOid, Oid domainNamespace, Oid baseTypeOid, pstate->p_pre_columnref_hook = replace_domain_constraint_value; pstate->p_ref_hook_state = (void *) domVal; - expr = transformExpr(pstate, constr->raw_expr, EXPR_KIND_DOMAIN_CHECK); + /* + * Transform the expression; first we must copy the input, in case it's in + * plan cache. + */ + expr = transformExpr(pstate, copyObject(constr->raw_expr), + EXPR_KIND_DOMAIN_CHECK); /* * Make sure it yields a boolean result.