From ea8dc3b73f57fdb05df552fc56707b580530304c Mon Sep 17 00:00:00 2001 From: Anthonin Bonnefoy Date: Wed, 22 Jul 2026 14:25:44 +0200 Subject: [PATCH v3] Fix error handling in getCopyDataMessage() and pqFunctionCall3() Commit f6f0542266f0 changed getNotify(), getParameterStatus(), and related libpq message-processing paths to abandon the connection on out-of-memory errors. However, getCopyDataMessage() and pqFunctionCall3() did not handle this new fatal-error state. Both can process asynchronous NotificationResponse and ParameterStatus messages while waiting for other responses. If one of those messages triggered a fatal error, these loops continued processing instead of reporting it immediately. Fix this by checking for a saved fatal error after processing an asynchronous message. If the connection has been abandoned, return the appropriate error immediately instead of continuing to parse input. Backpatch to v18, where commit f6f0542266f0 introduced this issue. Author: Anthonin Bonnefoy Reviewed-by: Ewan Young Reviewed-by: Fujii Masao Discussion: https://postgr.es/m/CAO6_XqpGfm+XHE1OzS=_+jroeDOxhhGa11P3cbm9q2gT05yorA@mail.gmail.com Backpatch-through: 18 --- src/interfaces/libpq/fe-protocol3.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/src/interfaces/libpq/fe-protocol3.c b/src/interfaces/libpq/fe-protocol3.c index 9d6a285fb28..f807670409c 100644 --- a/src/interfaces/libpq/fe-protocol3.c +++ b/src/interfaces/libpq/fe-protocol3.c @@ -1931,6 +1931,13 @@ getCopyDataMessage(PGconn *conn) return -1; } + /* + * An error may have been triggered while processing the message, + * report it if it's the case + */ + if (conn->error_result && conn->status == CONNECTION_BAD) + return -2; + /* Drop the processed message and loop around for another */ pqParseDone(conn, conn->inCursor); } @@ -2425,6 +2432,13 @@ pqFunctionCall3(PGconn *conn, Oid fnid, return pqPrepareAsyncResult(conn); } + /* + * An error may have been triggered while processing the message, bail + * out + */ + if (conn->error_result && conn->status == CONNECTION_BAD) + return pqPrepareAsyncResult(conn); + /* Completed parsing this message, keep going */ pqParseDone(conn, conn->inStart + 5 + msgLength); needInput = false; -- 2.55.0