pg_ctl: Disable autoruns for cmd.exe on Windows

michaelpq · pull[bot] · commit 277c6bcb2fc1 · 2024-04-18T06:51:38.000Z
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 is arguably a bug, but no backpatch is done now out of caution. 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
diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
@@ -552,11 +552,11 @@ 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))
