xen: xenbus_dev_frontend: Really return response string

[ Upstream commit ebf04f331f ]

xenbus_command_reply() did not actually copy the response string and
leaked stack content instead.

Fixes: 9a6161fe73 ("xen: return xenstore command failures via response instead of rc")
Signed-off-by: Simon Gaiser <simon@invisiblethingslab.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Simon Gaiser 2018-03-15 04:08:03 +01:00 коммит произвёл Greg Kroah-Hartman
Родитель d5cf1ed8d3
Коммит ff3080bab1
1 изменённых файлов: 2 добавлений и 1 удалений

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@ -403,7 +403,7 @@ static int xenbus_command_reply(struct xenbus_file_priv *u,
{ {
struct { struct {
struct xsd_sockmsg hdr; struct xsd_sockmsg hdr;
const char body[16]; char body[16];
} msg; } msg;
int rc; int rc;
@ -412,6 +412,7 @@ static int xenbus_command_reply(struct xenbus_file_priv *u,
msg.hdr.len = strlen(reply) + 1; msg.hdr.len = strlen(reply) + 1;
if (msg.hdr.len > sizeof(msg.body)) if (msg.hdr.len > sizeof(msg.body))
return -E2BIG; return -E2BIG;
memcpy(&msg.body, reply, msg.hdr.len);
mutex_lock(&u->reply_mutex); mutex_lock(&u->reply_mutex);
rc = queue_reply(&u->read_buffers, &msg, sizeof(msg.hdr) + msg.hdr.len); rc = queue_reply(&u->read_buffers, &msg, sizeof(msg.hdr) + msg.hdr.len);