From: Michael Paquier <michael@paquier.xyz>
Date: Thu, 30 Apr 2026 09:44:41 +0000 (+0900)
Subject: Fix errno check based on EINTR in pg_flush_data()
X-Git-Tag: REL_18_4~39
X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=6cb307251c5c6261286c1566496920976640108e;p=thirdparty%2Fpostgresql.git

Fix errno check based on EINTR in pg_flush_data()

Upon a failure of sync_file_range(), EINTR was checked based on the
returned result of the routine rather than its errno.  sync_file_range()
returns -1 on failure, making the check a no-op, invalidating the retry
attempt in this case.

Oversight in 0d369ac65004.

Author: DaeMyung Kang <charsyam@gmail.com>
Discussion: https://postgr.es/m/20260429151811.1810874-1-charsyam@gmail.com
Backpatch-through: 16
---

diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index 73fa05278a3..378c078c7c7 100644
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -562,7 +562,7 @@ retry:
 		{
 			int			elevel;
 
-			if (rc == EINTR)
+			if (errno == EINTR)
 				goto retry;
 
 			/*