diff --git a/udev/udevd.c b/udev/udevd.c index 7abfa1b..99473da 100644 --- a/udev/udevd.c +++ b/udev/udevd.c @@ -615,16 +615,31 @@ static struct udevd_uevent_msg *get_netlink_msg(struct udev *udev) struct udevd_uevent_msg *msg; int bufpos; ssize_t size; + struct sockaddr_nl snl; + struct msghdr smsg; + struct iovec iov; static char buffer[UEVENT_BUFFER_SIZE+512]; char *pos; - size = recv(uevent_netlink_sock, &buffer, sizeof(buffer), 0); + iov.iov_base = buffer; + iov.iov_len = sizeof(buffer); + smsg.msg_name = &snl; + smsg.msg_namelen = sizeof(struct sockaddr_nl); + smsg.msg_iov = &iov; + smsg.msg_iovlen = 1; + size = recvmsg(uevent_netlink_sock, &smsg, 0); if (size < 0) { if (errno != EINTR) err(udev, "unable to receive kernel netlink message: %s\n", strerror(errno)); return NULL; } + if ((snl.nl_groups != 1) || (snl.nl_pid != 0)) { + info(udev, "ignored netlink message from invalid group/sender %d/%d\n", + snl.nl_groups, snl.nl_pid); + return NULL; + } + if ((size_t)size > sizeof(buffer)-1) size = sizeof(buffer)-1; buffer[size] = '\0';