From: Christian Brauner <christian.brauner@ubuntu.com>
Date: Wed, 15 Nov 2017 15:04:12 +0000 (+0100)
Subject: commands: only set ringbuffer datalen when needed
X-Git-Tag: lxc-3.0.0.beta1~182^2~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5928191e83fdb99e45b830f0a7b95bd99eca1d4f;p=thirdparty%2Flxc.git

commands: only set ringbuffer datalen when needed

If we do it unconditionally a request to only clear the ringbuffer and not read
or write anything will fail.

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---

diff --git a/src/lxc/commands.c b/src/lxc/commands.c
index c158672ed..759346b8b 100644
--- a/src/lxc/commands.c
+++ b/src/lxc/commands.c
@@ -1037,7 +1037,9 @@ static int lxc_cmd_console_log_callback(int fd, struct lxc_cmd_req *req,
 	if (buffer_size <= 0)
 		goto out;
 
-	rsp.datalen = lxc_ringbuf_used(buf);
+	if (log->read || log->write_logfile)
+		rsp.datalen = lxc_ringbuf_used(buf);
+
 	if (log->read)
 		rsp.data = lxc_ringbuf_get_read_addr(buf);