pg_ctl: Disable autoruns for cmd.exe on Windows

michaelpq · michaelpq · commit 714bfb7813ed · 2024-01-12T13:53:07.000+09:00
On Windows, cmd.exe is used to launch the postmaster process to ease its redirection setup. However, cmd.exe may execute other programs at startup due to autorun configurations, which could influence the postmaster startup. This patch adds /D flag to the launcher cmd.exe command line to disable autorun settings written in the registry. This was originally applied on HEAD as of 9886744 without a backpatch, but the patch has survived CI and buildfarm cycles. I have checked that cmd /d exists down to Windows XP, which should make this change work correctly in the oldest branches still supported. Reported-by: Hayato Kuroda Author: Kyotaro Horiguchi Reviewed-by: Robert Haas, Michael Paquier Discussion: https://postgr.es/m/20230922.161551.320043332510268554.horikyota.ntt@gmail.com Backpatch-through: 12
diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
@@ -553,11 +553,11 @@ start_postmaster(void)
 		else
 			close(fd);
 
-		cmd = psprintf("\"%s\" /C \"\"%s\" %s%s < \"%s\" >> \"%s\" 2>&1\"",
+		cmd = psprintf("\"%s\" /D /C \"\"%s\" %s%s < \"%s\" >> \"%s\" 2>&1\"",
 					   comspec, exec_path, pgdata_opt, post_opts, DEVNULL, log_file);
 	}
 	else
-		cmd = psprintf("\"%s\" /C \"\"%s\" %s%s < \"%s\" 2>&1\"",
+		cmd = psprintf("\"%s\" /D /C \"\"%s\" %s%s < \"%s\" 2>&1\"",
 					   comspec, exec_path, pgdata_opt, post_opts, DEVNULL);
 
 	if (!CreateRestrictedProcess(cmd, &pi, false))
