Re: UPDATE on Domain Array that is based on a composite key crashes

On Tue, Oct 19, 2021 at 12:39 AM Onder Kalaci <onderk(at)microsoft(dot)com> wrote:

> Hi hackers,
>
>
>
> I couldn’t find a similar report to this one, so starting a new thread. I
> can reproduce this on v14.0 as well as PostgreSQL 12.5 (not tried below
> versions).
>
>
>
> Steps to reproduce:
>
>
>
> CREATE TYPE two_ints as (if1 int, if2 int);
>
> CREATE DOMAIN domain AS two_ints CHECK ((VALUE).if1 > 0);
>
> CREATE TABLE domain_indirection_test (f1 int, f3 domain, domain_array
> domain[]);
>
> INSERT INTO domain_indirection_test (f1,f3.if1) VALUES (0, 1);
>
> UPDATE domain_indirection_test SET domain_array[0].if2 = 5;
>
> server closed the connection unexpectedly
>
> This probably means the server terminated abnormally
>
> before or while processing the request.
>
> The connection to the server was lost. Attempting reset: Failed.
>
> Time: 3.990 ms
>
> @:-!>
>
>
>
>
>
> The backtrace on PG 12.5 (As far as I remember, PG14 looks very similar) :
>
>
>
> (lldb) bt
>
> * thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS
> (code=1, address=0x0)
>
> * frame #0: 0x00000001036584b7
> postgres`pg_detoast_datum(datum=0x0000000000000000) at fmgr.c:1741:6
>
> frame #1: 0x0000000103439a86
> postgres`ExecEvalFieldStoreDeForm(state=<unavailable>,
> op=0x00007f9212045df8, econtext=<unavailable>) at execExprInterp.c:3025:12
>
> frame #2: 0x000000010343834e
> postgres`ExecInterpExpr(state=<unavailable>, econtext=<unavailable>,
> isnull=0x00007ffeec91fdc7) at execExprInterp.c:1337:4
>
> frame #3: 0x000000010343742b
> postgres`ExecInterpExprStillValid(state=0x00007f921181db18,
> econtext=0x00007f921181d670, isNull=<unavailable>) at
> execExprInterp.c:1778:9
>
> frame #4: 0x0000000103444e0d
> postgres`ExecEvalExprSwitchContext(state=0x00007f921181db18,
> econtext=0x00007f921181d670, isNull=<unavailable>) at executor.h:310:13
>
> frame #5: 0x0000000103444cf0
> postgres`ExecProject(projInfo=0x00007f921181db10) at executor.h:344:9
>
> frame #6: 0x0000000103444af6
> postgres`ExecScan(node=0x00007f921181d560, accessMtd=(postgres`SeqNext at
> nodeSeqscan.c:51), recheckMtd=(postgres`SeqRecheck at nodeSeqscan.c:90)) at
> execScan.c:239:12
>
> frame #7: 0x0000000103461d17
> postgres`ExecSeqScan(pstate=<unavailable>) at nodeSeqscan.c:112:9
>
> frame #8: 0x000000010344375c
> postgres`ExecProcNodeFirst(node=0x00007f921181d560) at execProcnode.c:445:9
>
> frame #9: 0x000000010345eefe
> postgres`ExecProcNode(node=0x00007f921181d560) at executor.h:242:9
>
> frame #10: 0x000000010345e74f
> postgres`ExecModifyTable(pstate=0x00007f921181d090) at
> nodeModifyTable.c:2079:14
>
> frame #11: 0x000000010344375c
> postgres`ExecProcNodeFirst(node=0x00007f921181d090) at execProcnode.c:445:9
>
> frame #12: 0x000000010343f25e
> postgres`ExecProcNode(node=0x00007f921181d090) at executor.h:242:9
>
> frame #13: 0x000000010343d80d
> postgres`ExecutePlan(estate=0x00007f921181cd10,
> planstate=0x00007f921181d090, use_parallel_mode=<unavailable>,
> operation=CMD_UPDATE, sendTuples=false, numberTuples=0,
> direction=ForwardScanDirection, dest=0x00007f9211818c38,
> execute_once=<unavailable>) at execMain.c:1646:10
>
> frame #14: 0x000000010343d745
> postgres`standard_ExecutorRun(queryDesc=0x00007f921180e310,
> direction=ForwardScanDirection, count=0, execute_once=true) at
> execMain.c:364:3
>
> frame #15: 0x000000010343d67c
> postgres`ExecutorRun(queryDesc=0x00007f921180e310,
> direction=ForwardScanDirection, count=0, execute_once=<unavailable>) at
> execMain.c:308:3
>
> frame #16: 0x00000001035784a8
> postgres`ProcessQuery(plan=<unavailable>, sourceText=<unavailable>,
> params=<unavailable>, queryEnv=0x0000000000000000, dest=<unavailable>,
> completionTag="") at pquery.c:161:2
>
> frame #17: 0x0000000103577c5e
> postgres`PortalRunMulti(portal=0x00007f9215024110, isTopLevel=true,
> setHoldSnapshot=false, dest=0x00007f9211818c38, altdest=0x00007f9211818c38,
> completionTag="") at pquery.c:0
>
> frame #18: 0x000000010357763d
> postgres`PortalRun(portal=0x00007f9215024110, count=9223372036854775807,
> isTopLevel=<unavailable>, run_once=<unavailable>, dest=0x00007f9211818c38,
> altdest=0x00007f9211818c38, completionTag="") at pquery.c:796:5
>
> frame #19: 0x0000000103574f87
> postgres`exec_simple_query(query_string="UPDATE domain_indirection_test SET
> domain_array[0].if2 = 5;") at postgres.c:1215:10
>
> frame #20: 0x00000001035746b8
> postgres`PostgresMain(argc=<unavailable>, argv=<unavailable>,
> dbname=<unavailable>, username=<unavailable>) at postgres.c:0
>
> frame #21: 0x000000010350d712 postgres`BackendRun(port=<unavailable>)
> at postmaster.c:4494:2
>
> frame #22: 0x000000010350cffa
> postgres`BackendStartup(port=<unavailable>) at postmaster.c:4177:3
>
> frame #23: 0x000000010350c59c postgres`ServerLoop at
> postmaster.c:1725:7
>
> frame #24: 0x000000010350ac8d postgres`PostmasterMain(argc=3,
> argv=0x00007f9210d049c0) at postmaster.c:1398:11
>
> frame #25: 0x000000010347fbdd postgres`main(argc=<unavailable>,
> argv=<unavailable>) at main.c:228:3
>
> frame #26: 0x00007fff204e8f3d libdyld.dylib`start + 1
>
>
>
>
>
> Thanks,
>
> Onder KALACI
>
> Software Engineer at Microsoft &
>
> Developing the Citus database extension for PostgreSQL
>

Hi,
It seems the following change would fix the crash:

diff --git a/src/postgres/src/backend/executor/execExprInterp.c
b/src/postgres/src/backend/executor/execExprInterp.c
index 622cab9d4..50cb4f014 100644
--- a/src/postgres/src/backend/executor/execExprInterp.c
+++ b/src/postgres/src/backend/executor/execExprInterp.c
@@ -3038,6 +3038,9 @@ ExecEvalFieldStoreDeForm(ExprState *state,
ExprEvalStep *op, ExprContext *econte
HeapTupleHeader tuphdr;
HeapTupleData tmptup;

+ if (DatumGetPointer(tupDatum) == NULL) {
+ return;
+ }
tuphdr = DatumGetHeapTupleHeader(tupDatum);
tmptup.t_len = HeapTupleHeaderGetDatumLength(tuphdr);
ItemPointerSetInvalid(&(tmptup.t_self));

Here is the result after the update statement:

# UPDATE domain_indirection_test SET domain_array[0].if2 = 5;
UPDATE 1
# select * from domain_indirection_test;
f1 | f3 | domain_array
----+------+----------------
0 | (1,) | [0:0]={"(,5)"}
(1 row)

Cheers