4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Simon Gaiser <simon@xxxxxxxxxxxxxxxxxxxxxx> [ Upstream commit ebf04f331fa15a966262341a7dc6b1a0efd633e4 ] xenbus_command_reply() did not actually copy the response string and leaked stack content instead. Fixes: 9a6161fe73bd ("xen: return xenstore command failures via response instead of rc") Signed-off-by: Simon Gaiser <simon@xxxxxxxxxxxxxxxxxxxxxx> Reviewed-by: Juergen Gross <jgross@xxxxxxxx> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/xen/xenbus/xenbus_dev_frontend.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/xen/xenbus/xenbus_dev_frontend.c +++ b/drivers/xen/xenbus/xenbus_dev_frontend.c @@ -403,7 +403,7 @@ static int xenbus_command_reply(struct x { struct { struct xsd_sockmsg hdr; - const char body[16]; + char body[16]; } msg; int rc; @@ -412,6 +412,7 @@ static int xenbus_command_reply(struct x msg.hdr.len = strlen(reply) + 1; if (msg.hdr.len > sizeof(msg.body)) return -E2BIG; + memcpy(&msg.body, reply, msg.hdr.len); mutex_lock(&u->reply_mutex); rc = queue_reply(&u->read_buffers, &msg, sizeof(msg.hdr) + msg.hdr.len);