mirrors/postgres
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Fix WaitEventSet resource leak in WaitLatchOrSocket().

Browse Source 
This function would have the same issue we solved in commit 501cfd07d:
If an error is thrown after calling CreateWaitEventSet(), the file
descriptor (on epoll- or kqueue-based systems) or handles (on Windows)
that the WaitEventSet contains are leaked.

Like that commit, use PG_TRY-PG_FINALLY (PG_TRY-PG_CATCH in v12) to make
sure the WaitEventSet is freed properly.

Back-patch to all supported versions, but as we do not have this issue
in HEAD (cf. commit 50c67c201), no need to apply this patch to it.

Discussion: https://postgr.es/m/CAPmGK16MqdDoD8oatp8SQWaEa4vS3nfQqDN_Sj9YRuu5J3Lj9g%40mail.gmail.com
This commit is contained in:
Etsuro Fujita 2024-04-11 19:05:05 +09:00
parent f5cee411a1
commit 01b01a77fe
1 changed files with 43 additions and 37 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

80
src/backend/storage/ipc/latch.c
View File

@ -395,48 +395,54 @@ WaitLatchOrSocket(Latch *latch, int wakeEvents, pgsocket sock,
WaitEvent event;
WaitEventSet *set = CreateWaitEventSet(CurrentMemoryContext, 3);
if (wakeEvents & WL_TIMEOUT)
Assert(timeout >= 0);
else
timeout = -1;
if (wakeEvents & WL_LATCH_SET)
AddWaitEventToSet(set, WL_LATCH_SET, PGINVALID_SOCKET,
latch, NULL);
/* Postmaster-managed callers must handle postmaster death somehow. */
Assert(!IsUnderPostmaster ||
(wakeEvents & WL_EXIT_ON_PM_DEATH) ||
(wakeEvents & WL_POSTMASTER_DEATH));
if ((wakeEvents & WL_POSTMASTER_DEATH) && IsUnderPostmaster)
AddWaitEventToSet(set, WL_POSTMASTER_DEATH, PGINVALID_SOCKET,
NULL, NULL);
if ((wakeEvents & WL_EXIT_ON_PM_DEATH) && IsUnderPostmaster)
AddWaitEventToSet(set, WL_EXIT_ON_PM_DEATH, PGINVALID_SOCKET,
NULL, NULL);
if (wakeEvents & WL_SOCKET_MASK)
PG_TRY();
{
int ev;
if (wakeEvents & WL_TIMEOUT)
Assert(timeout >= 0);
else
timeout = -1;
ev = wakeEvents & WL_SOCKET_MASK;
AddWaitEventToSet(set, ev, sock, NULL, NULL);
if (wakeEvents & WL_LATCH_SET)
AddWaitEventToSet(set, WL_LATCH_SET, PGINVALID_SOCKET,
latch, NULL);
/* Postmaster-managed callers must handle postmaster death somehow. */
Assert(!IsUnderPostmaster ||
(wakeEvents & WL_EXIT_ON_PM_DEATH) ||
(wakeEvents & WL_POSTMASTER_DEATH));
if ((wakeEvents & WL_POSTMASTER_DEATH) && IsUnderPostmaster)
AddWaitEventToSet(set, WL_POSTMASTER_DEATH, PGINVALID_SOCKET,
NULL, NULL);
if ((wakeEvents & WL_EXIT_ON_PM_DEATH) && IsUnderPostmaster)
AddWaitEventToSet(set, WL_EXIT_ON_PM_DEATH, PGINVALID_SOCKET,
NULL, NULL);
if (wakeEvents & WL_SOCKET_MASK)
{
int ev;
ev = wakeEvents & WL_SOCKET_MASK;
AddWaitEventToSet(set, ev, sock, NULL, NULL);
}
rc = WaitEventSetWait(set, timeout, &event, 1, wait_event_info);
if (rc == 0)
ret |= WL_TIMEOUT;
else
{
ret |= event.events & (WL_LATCH_SET |
WL_POSTMASTER_DEATH |
WL_SOCKET_MASK);
}
}
rc = WaitEventSetWait(set, timeout, &event, 1, wait_event_info);
if (rc == 0)
ret |= WL_TIMEOUT;
else
PG_FINALLY();
{
ret |= event.events & (WL_LATCH_SET |
WL_POSTMASTER_DEATH |
WL_SOCKET_MASK);
FreeWaitEventSet(set);
}
FreeWaitEventSet(set);
PG_END_TRY();
return ret;
}