From: Willy Tarreau <w@1wt.eu>
Date: Wed, 24 Feb 2021 10:11:06 +0000 (+0100)
Subject: BUG/MEDIUM: cli/shutdown sessions: make it thread-safe
X-Git-Tag: v2.4-dev10~70
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3f5dd2945ccbed6b4baf23a453e9d1d071a2d835;p=thirdparty%2Fhaproxy.git

BUG/MEDIUM: cli/shutdown sessions: make it thread-safe

There's no locking around the lookup of a stream nor its shutdown
when issuing "shutdown sessions" over the CLI so the risk of crashing
the process is particularly high.

Let's use a thread_isolate() there which is suitable for this task, and
there are not that many alternatives.

This must be backported to 1.8.
---

diff --git a/src/stream.c b/src/stream.c
index 6d534cdec2..1dfbd361ac 100644
--- a/src/stream.c
+++ b/src/stream.c
@@ -3444,17 +3444,22 @@ static int cli_parse_shutdown_session(char **args, char *payload, struct appctx
 
 	ptr = (void *)strtoul(args[2], NULL, 0);
 
+	thread_isolate();
+
 	/* first, look for the requested stream in the stream table */
 	list_for_each_entry(strm, &streams, list) {
-		if (strm == ptr)
+		if (strm == ptr) {
+			stream_shutdown(strm, SF_ERR_KILLED);
 			break;
+		}
 	}
 
+	thread_release();
+
 	/* do we have the stream ? */
 	if (strm != ptr)
 		return cli_err(appctx, "No such session (use 'show sess').\n");
 
-	stream_shutdown(strm, SF_ERR_KILLED);
 	return 1;
 }