Tools: hv: verify origin of netlink connector message
Olaf Hering [Thu, 31 May 2012 14:40:06 +0000 (16:40 +0200)]
commit bcc2c9c3fff859e0eb019fe6fec26f9b8eba795c upstream.

The SuSE security team suggested to use recvfrom instead of recv to be
certain that the connector message is originated from kernel.

CVE-2012-2669

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Marcus Meissner <meissner@suse.de>
Signed-off-by: Sebastian Krahmer <krahmer@suse.de>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tools/hv/hv_kvp_daemon.c

index 146fd61..d9834b3 100644 (file)
@@ -701,14 +701,18 @@ int main(void)
        pfd.fd = fd;
 
        while (1) {
+               struct sockaddr *addr_p = (struct sockaddr *) &addr;
+               socklen_t addr_l = sizeof(addr);
                pfd.events = POLLIN;
                pfd.revents = 0;
                poll(&pfd, 1, -1);
 
-               len = recv(fd, kvp_recv_buffer, sizeof(kvp_recv_buffer), 0);
+               len = recvfrom(fd, kvp_recv_buffer, sizeof(kvp_recv_buffer), 0,
+                               addr_p, &addr_l);
 
-               if (len < 0) {
-                       syslog(LOG_ERR, "recv failed; error:%d", len);
+               if (len < 0 || addr.nl_pid) {
+                       syslog(LOG_ERR, "recvfrom failed; pid:%u error:%d %s",
+                                       addr.nl_pid, errno, strerror(errno));
                        close(fd);
                        return -1;
                }